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000
FXUS61 KGYX 221111
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
611 AM EST MON DEC 22 2014

.SYNOPSIS...
AN ONSHORE FLOW MAY PRODUCE SOME FLURRIES OR LIGHT SNOW MAINLY
OVER SOUTHERN REGIONS RIGHT THROUGH TUESDAY. A SIGNIFICANT LOW
PRESSURE SYSTEM WILL GRADUALLY ORGANIZE WEDNESDAY...BEFORE MOVING
OVER THE GREAT LAKES. THIS COULD BRING WINDY CONDITIONS AND THE
POTENTIAL FOR HEAVY RAIN AROUND CHRISTMAS EVE INTO EARLY CHRISTMAS
MORNING. ANOTHER LOW PRESSURE SYSTEM WILL PASS BY TO OUR NORTHWEST
LATE IN THE WEEK AND EARLY NEXT WEEKEND.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...

608 AM...MINOR ESTF UPDATE TO 1ST PERIOD GRIDS TO INGEST CURRENT
MESONET.

AT 07Z...A 1032 MILLIBAR HIGH WAS CENTERED VICINITY OF THE GASPE
PENINSULA. THE HIGH WILL GRADUALLY RETREAT TO THE NORTHEAST
TODAY. COLD ONSHORE FLOW AROUND THIS HIGH WILL PRODUCE SOME
SCATTERED OCEAN EFFECT SNOW SHOWERS OR FLURRIES TODAY MAINLY
ACROSS SOUTHERN AND COASTAL SECTIONS TODAY.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
SCATTERED SNOW SHOWERS AND FLURRIES WILL CONTINUE THROUGH TONIGHT
BECAUSE OF THE PERSISTENT ONSHORE FLOW. COLD AIR DAMMING SHOULD
KEEP THE COLUMN COLD ENOUGH TONIGHT FOR ANY LIGHT PRECIPITATION TO
FALL LARGELY AS SNOW.

BY TUESDAY MORNING...WARM AIR ADVECTION PRECIPITATION AHEAD OF THE
MIDWEST STORM SYSTEM SHOULD BEGIN TO OVERSPREAD THE FORECAST AREA
FROM SOUTH TO NORTH. THERE COULD BE A BRIEF PERIOD OF LIGHT
FREEZING DRIZZLE OR RAIN AS THE WARMER AIR BEGINS TO OVERSPREAD
THE AREA...AS MODELS HINT AT COLD AIR DAMMING ACROSS THE INTERIOR.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
EXTENDED PERIOD WX TO BE DRIVEN BY SERIES OF DOWNSTREAM BLOCKS OVER
THE ATLANTIC AND EUROPE...WHICH WILL HELP BUILD RIDGING AND HIGHER
AMPLITUDE THROUGH THE WEEK AND INTO EARLY NEXT WEEKEND...BEFORE
THERE ARE SIGNS OF THE BLOCKING BREAKING DOWN AND ALLOWING COLDER
AIR TO MOVE IN.

WE START THE PERIOD DURING THE CHRISTMAS HOLIDAY PERIOD AND THE
PREVIOUSLY ADVERTISED STORM SYSTEM THAT WILL THE CWA WED INTO THU.
MOST OF THE SHORT TO MEDIUM RANGE MODELS HAVE INTRODUCED AN
IMPORTANT CHANGE TO THE FORECAST...AND THAT ALLOWS THE FIRST NRN
STREAM 500MB WAVE TO PASS BY WITH OUT MUCH INTERACTION WITH THE
LARGER SCALE TROUGH...WHICH LINGERS OVER THE GULF STATES UNTIL
EARLY WED MORNING. THIS WOULD MAKE FOR A LESS IMPRESSIVE SFC LOW
THAT INTENSIFIES LATER AND FURTHER N...WHICH WOULD LIMIT THE
DEVELOPMENT OF THE LOW LVL JET...AND THEREFORE BRING DOWN
QPF...AND ALSO LOWER THE HTREAT FRO STRONG WINDS. THIS SCENARIO IS
SUPPORTED BY THE 00Z EURO AND GFS...AND TO SOME DEGREE THE
NAM...ALTHOUGH THAT REALLY HOLDS BACK THE 500 MB CLOSED LOW. THE
00Z CMC HEMI IS THE ONE MODEL THAT TEND TOWARD BETTER PHASING AND
HOLDS ONTO A STRONGER SINGLE SFC LOW. THESE CHANGES IN THE MODELS
MAY BE THE RESULT ONE OR ALL OF THE WAVES INVOLVED IN GETTING THIS
STORM TOGETHER HAVE MOVES INTO A MORE WELL SAMPLED PART OF THE
MODEL DOMAIN. THERES ALSO STILL THE ISSUE OF DEEP CONVECTION IN
THE FORECAST TUE AFFECTING THE MODELS AS WELL. GIVEN ALL THAT WILL
BE STICKING CLOSER TO THE GFS/EURO...AND BLENDING BACK IN SOME OF
THE PREVIOUS FORECAST...PARTIALLY FOR THE SAKE OF CONTINUITY.

OVERALL...THE SAME ISSUES PREVAIL FROM PREVIOUS
FORECASTS...ALTHOUGH TO A LESSER DEGREE...AND IT WILL PRETTY MUCH
BE PRECIPITATING /MOSTLY RAIN/ FROM TUESDAY RIGHT INTO CHRISTMAS
MORNING. THE FIRST CHANGE IN THE FORECAST WILL BE THAT THE COLDER
AIR WILL HANG ON LONGER...INTO WED MORNING. IN MOST PLACES TEMPS
WILL BE ABV FREEZING THRU TUE NIGHT...BUT WE COULD SEE A PERIOD
OF FZRA IN THE MTNS...WITH A TENTH OR TWO OF ICE ACCUMS BEFORE
TEMPS RISE ABV THERE BY MIDDAY. S WINDS WILL PICK UP...BUT NOT
UNTIL LATER IN THE DAY WED...AND WILL LKLY NOT BE AS GUSTY WED
NIGHT...BUT COULD GUST TO 30 MPH OR IN THE W FLOW BEHIND THE LOW
ON THU. QPF WAS LOWERED TOO...BUT STILL WILL SEE A PERIOD OF HEAVY
RAIN...BUT THAT WILL PROBABLY BE LIMITED TO WED NIGHT. QPF AROUND
2 INCHES ACROSS THE CWA...LOWEST N OF THE MTNS AND HIGHEST IN THE
UPSLOPE AREAS. ALSO...THE WARMER AIR WILL NOT COME IN AS QUICKLY
AND THIS WILL HELP LIMIT SNOW MELT AND THUS MITIGATING THE
FLOODING THREAT SOME. STILL...WILL SEE ENOUGH RAIN THAT SOME
FLOODING PROBLEMS ARE POSSIBLE. FINALLY TEMPS WILL PUSH UP INTO
THE 50S IN THE SRN ZONES...WITH THE WARMEST READINGS LKLY WED
NIGHT INTO THU MORNING.

ALTHOUGH IT COOLS DOWN SOMEWHAT BEHIND THEIS SYSTEM...TEMPS WILL
REMAIN ABV NORMAL...BY 5-10F FRI AND SAT AS HIGH PRES BUILDS IN.
NEXT CHC FOR ANY SIGNIF PRECIP WILL BE LATE IN THE WEEKEND.

&&

.AVIATION /11Z MONDAY THROUGH FRIDAY/...
SHORT TERM...MAINLY VFR THROUGH TONIGHT...HOWEVER THERE MAY BE
BRIEFLY MVFR CONDITIONS IN SCATTERED SNOW SHOWERS SOUTHERN
LOCATIONS. MVFR CONDS EXPECTED FOR TUE.

LONG TERM...EXTENDED PERIOD OF FLIGHT RESTRICTIONS TUS NIGHT INTO
THU MORNING. LOOK FOR IFR OR LOWER TUE NIGHT...WITH SOME
IMPROVEMENT TO MVFR DURING THE DAY WED...AND A RETURN TO IFR WED
NIGHT. EXPECT IMPROVEMENT TO VFR THU AFTERNOON...WHICH SHOULD
HOLD THRU FRIDAY.

&&

.MARINE...
SHORT TERM...WINDS AND SEAS WILL REMAIN BELOW SCA CONDITIONS
THROUGH LATE TONIGHT. AN SCA WILL LIKELY BE NEEDED BY TUESDAY IN
INCREASING WINDS AND SEAS.

LONG TERM...MODELS CONTINUE TO BACK OFF THE STRONG WINDS WED INTO
THU...BUT STILL EXPECT A PERIOD OF GALES...POSSIBLE IN THE S FLOW
LATE WED AND WED NIGHT...BUT MORE LKLY IN STRONG W FLOW THU INTO
THU NIGHT.

&&

.HYDROLOGY...
MODELS CONTINUE TO BACK OFF ON RAINFALL TOTALS FOR
THE CHRISTMAS EVE/EARLY CHRISTMAS MORNING EVENT...BUT AREA STILL
AROUND 2 INCHES. HOPING THE SNOWPACK IN THE MOUNTAINS AND
FOOTHILLS WILL TAKE IN SOME OF THE RAINFALL IN THAT AREA...BUT
STILL EXPECT SOME RAPID RISES IN THE HEADWATERS. IN ANY
CASE...WHILE THE THREAT OF FLOODING IS LOWER...IT STILL REMAINS A
POSSIBILITY WED NIGHT INTO THU.

&&

.TIDES/COASTAL FLOODING...
ASTRONOMICAL TIDES ARE AT THEIR PEAK FOR THE MONTH. THIS...IN
COMBINATION WITH STRONG SOUTHERLY GALES WILL LIKELY ALLOW FOR
SOME STORM SURGE. WAVES PROB NOT QUITE AS HIGH AS PREV
FORECASTS...MAYBE 10 TO 12 FT...BUT THERE IS SOME POTENTIAL FOR
MINOR COASTAL FLOODING...WITH SPLASH OVER AND BEACH EROSION
DISTINCT POSSIBILITY.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.

&&

$$
ES



000
FXUS61 KGYX 221111
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
611 AM EST MON DEC 22 2014

.SYNOPSIS...
AN ONSHORE FLOW MAY PRODUCE SOME FLURRIES OR LIGHT SNOW MAINLY
OVER SOUTHERN REGIONS RIGHT THROUGH TUESDAY. A SIGNIFICANT LOW
PRESSURE SYSTEM WILL GRADUALLY ORGANIZE WEDNESDAY...BEFORE MOVING
OVER THE GREAT LAKES. THIS COULD BRING WINDY CONDITIONS AND THE
POTENTIAL FOR HEAVY RAIN AROUND CHRISTMAS EVE INTO EARLY CHRISTMAS
MORNING. ANOTHER LOW PRESSURE SYSTEM WILL PASS BY TO OUR NORTHWEST
LATE IN THE WEEK AND EARLY NEXT WEEKEND.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...

608 AM...MINOR ESTF UPDATE TO 1ST PERIOD GRIDS TO INGEST CURRENT
MESONET.

AT 07Z...A 1032 MILLIBAR HIGH WAS CENTERED VICINITY OF THE GASPE
PENINSULA. THE HIGH WILL GRADUALLY RETREAT TO THE NORTHEAST
TODAY. COLD ONSHORE FLOW AROUND THIS HIGH WILL PRODUCE SOME
SCATTERED OCEAN EFFECT SNOW SHOWERS OR FLURRIES TODAY MAINLY
ACROSS SOUTHERN AND COASTAL SECTIONS TODAY.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
SCATTERED SNOW SHOWERS AND FLURRIES WILL CONTINUE THROUGH TONIGHT
BECAUSE OF THE PERSISTENT ONSHORE FLOW. COLD AIR DAMMING SHOULD
KEEP THE COLUMN COLD ENOUGH TONIGHT FOR ANY LIGHT PRECIPITATION TO
FALL LARGELY AS SNOW.

BY TUESDAY MORNING...WARM AIR ADVECTION PRECIPITATION AHEAD OF THE
MIDWEST STORM SYSTEM SHOULD BEGIN TO OVERSPREAD THE FORECAST AREA
FROM SOUTH TO NORTH. THERE COULD BE A BRIEF PERIOD OF LIGHT
FREEZING DRIZZLE OR RAIN AS THE WARMER AIR BEGINS TO OVERSPREAD
THE AREA...AS MODELS HINT AT COLD AIR DAMMING ACROSS THE INTERIOR.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
EXTENDED PERIOD WX TO BE DRIVEN BY SERIES OF DOWNSTREAM BLOCKS OVER
THE ATLANTIC AND EUROPE...WHICH WILL HELP BUILD RIDGING AND HIGHER
AMPLITUDE THROUGH THE WEEK AND INTO EARLY NEXT WEEKEND...BEFORE
THERE ARE SIGNS OF THE BLOCKING BREAKING DOWN AND ALLOWING COLDER
AIR TO MOVE IN.

WE START THE PERIOD DURING THE CHRISTMAS HOLIDAY PERIOD AND THE
PREVIOUSLY ADVERTISED STORM SYSTEM THAT WILL THE CWA WED INTO THU.
MOST OF THE SHORT TO MEDIUM RANGE MODELS HAVE INTRODUCED AN
IMPORTANT CHANGE TO THE FORECAST...AND THAT ALLOWS THE FIRST NRN
STREAM 500MB WAVE TO PASS BY WITH OUT MUCH INTERACTION WITH THE
LARGER SCALE TROUGH...WHICH LINGERS OVER THE GULF STATES UNTIL
EARLY WED MORNING. THIS WOULD MAKE FOR A LESS IMPRESSIVE SFC LOW
THAT INTENSIFIES LATER AND FURTHER N...WHICH WOULD LIMIT THE
DEVELOPMENT OF THE LOW LVL JET...AND THEREFORE BRING DOWN
QPF...AND ALSO LOWER THE HTREAT FRO STRONG WINDS. THIS SCENARIO IS
SUPPORTED BY THE 00Z EURO AND GFS...AND TO SOME DEGREE THE
NAM...ALTHOUGH THAT REALLY HOLDS BACK THE 500 MB CLOSED LOW. THE
00Z CMC HEMI IS THE ONE MODEL THAT TEND TOWARD BETTER PHASING AND
HOLDS ONTO A STRONGER SINGLE SFC LOW. THESE CHANGES IN THE MODELS
MAY BE THE RESULT ONE OR ALL OF THE WAVES INVOLVED IN GETTING THIS
STORM TOGETHER HAVE MOVES INTO A MORE WELL SAMPLED PART OF THE
MODEL DOMAIN. THERES ALSO STILL THE ISSUE OF DEEP CONVECTION IN
THE FORECAST TUE AFFECTING THE MODELS AS WELL. GIVEN ALL THAT WILL
BE STICKING CLOSER TO THE GFS/EURO...AND BLENDING BACK IN SOME OF
THE PREVIOUS FORECAST...PARTIALLY FOR THE SAKE OF CONTINUITY.

OVERALL...THE SAME ISSUES PREVAIL FROM PREVIOUS
FORECASTS...ALTHOUGH TO A LESSER DEGREE...AND IT WILL PRETTY MUCH
BE PRECIPITATING /MOSTLY RAIN/ FROM TUESDAY RIGHT INTO CHRISTMAS
MORNING. THE FIRST CHANGE IN THE FORECAST WILL BE THAT THE COLDER
AIR WILL HANG ON LONGER...INTO WED MORNING. IN MOST PLACES TEMPS
WILL BE ABV FREEZING THRU TUE NIGHT...BUT WE COULD SEE A PERIOD
OF FZRA IN THE MTNS...WITH A TENTH OR TWO OF ICE ACCUMS BEFORE
TEMPS RISE ABV THERE BY MIDDAY. S WINDS WILL PICK UP...BUT NOT
UNTIL LATER IN THE DAY WED...AND WILL LKLY NOT BE AS GUSTY WED
NIGHT...BUT COULD GUST TO 30 MPH OR IN THE W FLOW BEHIND THE LOW
ON THU. QPF WAS LOWERED TOO...BUT STILL WILL SEE A PERIOD OF HEAVY
RAIN...BUT THAT WILL PROBABLY BE LIMITED TO WED NIGHT. QPF AROUND
2 INCHES ACROSS THE CWA...LOWEST N OF THE MTNS AND HIGHEST IN THE
UPSLOPE AREAS. ALSO...THE WARMER AIR WILL NOT COME IN AS QUICKLY
AND THIS WILL HELP LIMIT SNOW MELT AND THUS MITIGATING THE
FLOODING THREAT SOME. STILL...WILL SEE ENOUGH RAIN THAT SOME
FLOODING PROBLEMS ARE POSSIBLE. FINALLY TEMPS WILL PUSH UP INTO
THE 50S IN THE SRN ZONES...WITH THE WARMEST READINGS LKLY WED
NIGHT INTO THU MORNING.

ALTHOUGH IT COOLS DOWN SOMEWHAT BEHIND THEIS SYSTEM...TEMPS WILL
REMAIN ABV NORMAL...BY 5-10F FRI AND SAT AS HIGH PRES BUILDS IN.
NEXT CHC FOR ANY SIGNIF PRECIP WILL BE LATE IN THE WEEKEND.

&&

.AVIATION /11Z MONDAY THROUGH FRIDAY/...
SHORT TERM...MAINLY VFR THROUGH TONIGHT...HOWEVER THERE MAY BE
BRIEFLY MVFR CONDITIONS IN SCATTERED SNOW SHOWERS SOUTHERN
LOCATIONS. MVFR CONDS EXPECTED FOR TUE.

LONG TERM...EXTENDED PERIOD OF FLIGHT RESTRICTIONS TUS NIGHT INTO
THU MORNING. LOOK FOR IFR OR LOWER TUE NIGHT...WITH SOME
IMPROVEMENT TO MVFR DURING THE DAY WED...AND A RETURN TO IFR WED
NIGHT. EXPECT IMPROVEMENT TO VFR THU AFTERNOON...WHICH SHOULD
HOLD THRU FRIDAY.

&&

.MARINE...
SHORT TERM...WINDS AND SEAS WILL REMAIN BELOW SCA CONDITIONS
THROUGH LATE TONIGHT. AN SCA WILL LIKELY BE NEEDED BY TUESDAY IN
INCREASING WINDS AND SEAS.

LONG TERM...MODELS CONTINUE TO BACK OFF THE STRONG WINDS WED INTO
THU...BUT STILL EXPECT A PERIOD OF GALES...POSSIBLE IN THE S FLOW
LATE WED AND WED NIGHT...BUT MORE LKLY IN STRONG W FLOW THU INTO
THU NIGHT.

&&

.HYDROLOGY...
MODELS CONTINUE TO BACK OFF ON RAINFALL TOTALS FOR
THE CHRISTMAS EVE/EARLY CHRISTMAS MORNING EVENT...BUT AREA STILL
AROUND 2 INCHES. HOPING THE SNOWPACK IN THE MOUNTAINS AND
FOOTHILLS WILL TAKE IN SOME OF THE RAINFALL IN THAT AREA...BUT
STILL EXPECT SOME RAPID RISES IN THE HEADWATERS. IN ANY
CASE...WHILE THE THREAT OF FLOODING IS LOWER...IT STILL REMAINS A
POSSIBILITY WED NIGHT INTO THU.

&&

.TIDES/COASTAL FLOODING...
ASTRONOMICAL TIDES ARE AT THEIR PEAK FOR THE MONTH. THIS...IN
COMBINATION WITH STRONG SOUTHERLY GALES WILL LIKELY ALLOW FOR
SOME STORM SURGE. WAVES PROB NOT QUITE AS HIGH AS PREV
FORECASTS...MAYBE 10 TO 12 FT...BUT THERE IS SOME POTENTIAL FOR
MINOR COASTAL FLOODING...WITH SPLASH OVER AND BEACH EROSION
DISTINCT POSSIBILITY.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.

&&

$$
ES



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000
FXUS61 KBOX 220938
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
437 AM EST MON DEC 22 2014

.SYNOPSIS...

A WAVE OF LOW PRESSURE WILL BRING PERIODS OF WET WEATHER MAINLY LATE
TONIGHT INTO TUESDAY NIGHT...WHICH MAY BEGIN AS A BRIEF PERIOD OF
FROZEN PRECIPITATION ACROSS NORTHWEST AND NORTH CENTRAL
MASSACHUSETTS.  A MUCH STRONGER STORM PASSING WELL TO OUR WEST
WEDNESDAY INTO CHRISTMAS MORNING WILL BRING HEAVY RAIN...GUSTY WINDS
AND PROBABLY MINOR COASTAL FLOODING.  DRY WEATHER WITH ABOVE NORMAL
TEMPERATURES EXPECTED CHRISTMAS AFTERNOON INTO SATURDAY.  LOW
PRESSURE MAY BRING A RETURN TO UNSETTLED WEATHER BY NEXT SUNDAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...

UPPER LEVEL RIDGE BUILDS AHEAD OF DIGGING MIDWEST TROUGH WITH
HIGH PRESSURE REMAINING ANCHORED OVER THE CANADIAN MARITIMES
THROUGH TONIGHT.

EASTERLY FLOW WILL CONTINUE ONSHORE ALLOWING FOR THE PROFILE TO
CONTINUE TO MOISTEN IN THE LOW LEVELS. IF THIS MOISTURE DEEPENS
ENOUGH THEN WE COULD SEE LIGHT SHOWERS DEVELOP ESP ACROSS THE MASS
EAST COASTLINE. OTHERWISE DRIZZLE MAY BE THE MAIN FACTOR AS THE
UPPER LEVELS ARE FAIRLY DRY. OVERALL TODAY WILL BE A COOL AND CLOUDY
DAY WITH HIGHS ONLY REACHING IN THE UPPER 30S TO LOW 40S AS CROSS
SECTIONS ARE VERY MOIST IN THE LOW LEVELS.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...

TONIGHT INTO TOMORROW...

*LIGHT FREEZING RAIN IS POSSIBLE ACROSS THE INTERIOR NORTHWEST AND
  NORTHERN WORCESTER HILLS*

A WEAK AREA OF LOW PRESSURE DEVELOPS ALONG A WARM FRONT OFF THE MID
ATLANTIC...DRIFTING NORTHWARD TOWARD THE AREA. THIS LOW REMAINS WEAK
AS THE WARM FRONT MOVES SLOWLY NORTHWARD TONIGHT INTO TOMORROW.
DECENT WARM ADVECTION AHEAD OF THIS WAVE WITH SEVERAL HI-RES
GUIDANCE MODELS SHOWS A POTENTIAL FOR COLD AIR DAMMING ACROSS THE
INTERIOR INTO TUESDAY MORNING.  BIGGEST QUESTION WILL BE THE
MOISTURE POTENTIAL...IS THERE ENOUGH TO DEVELOP PRECIP ESP TONIGHT?
GUIDANCE DOES SHOW ENOUGH LIFT AHEAD OF APPROACHING SURFACE LOW PER
THE GFS/EC SO ANTICIPATE PRECIP TO DEVELOP AND OVERSPREAD ACROSS
SOUTHERN NEW ENGLAND. IF THIS PLAYS OUT WITH COLD AIR DAMMING AND
WARM AIR ADVECTION...THEN WE COULD SEE FREEZING RAIN/DRIZZLE ACROSS
THE INTERIOR NORTHWEST AND NORTHERN WORCESTER HILLS VERY LATE
TONIGHT INTO TUESDAY MORNING. A WINTER WEATHER ADVISORY MAY BE
NEEDED.

AS SURFACE LOW CONTINUES TO MOVE NORTHWARD...AND HIGH PRESSURE OVER
EASTERN CANADA...ANTICIPATE AN INCREASING LLJ. THIS SOUTHEASTERLY
JET WILL CONTINUE TO FEED MOISTURE INTO THE REGION AND WITH
SOUNDINGS SHOW A VERY SATURATED PROFILE COULD SEE NUMEROUS SHOWERS
WITH PERHAPS A FEW HEAVY DOWNPOURS. NOTICED GUIDANCE HAS
INCREASED THE QPF OVER THE PAST FEW DAYS. AS THE WEAK SURFACE LOW
MOVES NORTH OF SOUTHERN NEW ENGLAND...WARM FRONT WILL LIFT
NORTHWARD SO ALL PRECIP BY THE LATE MORNING WILL BE IN THE LIQUID
FORM.

WE COULD ALSO SEE SOME MINOR COASTAL FLOODING CONCERNS ON TUESDAY
WITH DUE EASTERLY FLOW INCREASING TO ABOUT 20 TO 25 MPH.  SEE BELOW
FOR MORE DETAILS.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...

HIGHLIGHTS...

* PERIODS OF RAIN TUE NIGHT INTO XMAS MORNING WILL BE HEAVY AT TIMES
* DRY BY CHRISTMAS AFTERNOON BUT WINDY
* TEMPS AROUND 60 FOR SOME LATE WED INTO CHRISTMAS MORNING
* DRY BUT ABOVE NORMAL TEMPS CONTINUE FRI AND SAT
* UNSETTLED WEATHER MAY RETURN BY SUN BUT LOW CONFIDENCE

DETAILS...

TUESDAY NIGHT INTO CHRISTMAS...

STRONG SHORTWAVE WILL DIG ACROSS THE CENTRAL U.S. AND ALLOW DEEP
SOUTH TO SOUTHWEST FLOW ALOFT ACROSS SOUTHERN NEW ENGLAND.  THIS
WILL SEND AND ANOMALOUS MILD AIRMASS INTO SOUTHERN NEW ENGLAND FOR
LATE DECEMBER.  GEFS SHOWING PWATS 4 TO 5 STANDARD DEVIATIONS ABOVE
NORMAL BY WED NIGHT ACROSS OUR REGION.  WHILE HEAVY RAIN IS STILL
EXPECTED...THE MODELS HAVE CUT DOWN ON THE QPF IN THE LAST FEW RUNS.
THE MAIN LOW STILL PASSES WELL TO OUR WEST ACROSS GREAT LAKES...BUT
THEIR SLOWER AND WEAKER WITH SECONDARY DEVELOPMENT ACROSS OUR
REGION.  THIS RESULTS IN A WEAKER LOW LEVEL JET...HENCE LESS QPF.
GIVEN ANOMALOUS PWATS IN PLACE...DO NOT WANT TO COMPLETELY LET OUR
GUARD DOWN WITH THE POTENTIAL FOR FLOODING...BUT DOES APPEAR
SOMEWHAT LESS OF A RISK THAN YESTERDAY.  NONETHELESS...STILL EXPECT
TYPICAL NUISANCE POOR DRAINAGE STREET FLOODING.

AS FOR TIMING...SOUTHERLY FLOW ALOFT WILL RESULT IN SCATTERED
SHOWERS TUE NIGHT.  BULK OF THE RAIN WILL OCCUR WED INTO EARLY
CHRISTMAS DAY WHEN STRONGEST FORCING COINCIDES HIGH PWAT AIRMASS.
SOME OF THIS RAIN WILL BE HEAVY AT TIMES MAY RESULT IN NUISANCE POOR
DRAINAGE STREET FLOODING.  STILL A LOW RISK FOR MORE SIGNIFICANT
FLOODING GIVEN EXTREMELY HIGH PWATS...BUT SLOWER DEVELOPMENT OF
SECONDARY LOW PRESSURE MAY BE A LIMITING FACTOR.  REGARDLESS...
EXPECT 1 TO 3 INCHES OF RAIN.  WILL CONTINUE TO MENTION A SLIGHT
CHANCE OF THUNDER WITH SHOWALTER INDICES NEAR ZERO.

THE BULK OF THE RAIN SHOULD COME TO AN END CHRISTMAS MORNING WITH
TEMPS PROBABLY AROUND 60 FOR MUCH OF THE REGION.  WHILE GUSTY
SOUTHERLY WINDS ARE EXPECTED WED NIGHT...INVERSION AND WEAKER LOW
LEVEL JET WILL PROBABLY KEEP MOST AREAS BELOW ADVISORY CRITERIA.
STILL HAVE TO WATCH FOR A SMALL WINDOW ON THE COASTAL PLAIN ESP IF
TEMPS CAN EXCEED 60...BUT HIGHER CONFIDENCE IN WIND ON CHRISTMAS
AFTERNOON AND EVENING BEHIND THE SYSTEM.  INCREASING WESTERLY WIND
ALOFT AND STEEPENING LAPSE RATES WILL BRING THE POTENTIAL FOR THESE
WINDS.  DECENT SHOT AT A PERIOD OF 35 TO 50 MPH GUSTS BEHIND THIS
SYSTEM CHRISTMAS AFTERNOON AND EVENING.  WHILE THE GFS IS AN
OUTLIER...IT WOULD EVEN SUGGEST THE POTENTIAL FOR HIGH WIND CRITERIA
TO BE MET WITH 70 KNOTS AT 850 MB.  THAT MAY BE OVERDONE...BUT
SOMETHING WILL HAVE TO KEEP AN EYE ON THE NEXT FEW DAYS.

FRIDAY AND SATURDAY...

UPPER LEVEL RIDGE OFF THE SOUTHEAST COAST WILL KEEP KEEP US IN MILD
SOUTHWEST FLOW ALOFT.  DRY WEATHER EXPECTED WITH FORCING FOR ANY
PRECIPITATION WILL TO OUR NORTHWEST.  HIGHS MAINLY IN THE 40S TO
LOWER 50S.

SUNDAY...

CONFIDENCE IN THE FORECAST GOES DOWN CONSIDERABLY OVER THIS TIME.
DEVELOPING UPPER LEVEL RIDGING INTO ALASKA WILL SEND THE POLAR JET
SOUTHWARD INTO THE CENTRAL U.S.  AT THE SAME TIME...UPPER LEVEL
RIDGE OFF THE SOUTHEAST COAST WILL TRY TO HANG TOUGH.  THE GFS
INSISTS ON DRY AND COLDER WEATHER ARRIVING...BUT WERE NOT CONVINCED.
GIVEN THE SOUTHEAST RIDGE...IT MAY HOLD THE COLD AIR UP AND ALLOW
DEVELOPING LOW PRESSURE TO TRACK NEAR NEW ENGLAND SUN AND SUN NIGHT.
THIS COULD BRING RAIN OR SNOW DEPENDING ON ITS TRACK...OBVIOUSLY A
WEEK OUT SO PLENTY OF UNCERTAINTY BUT WOULD LEAN TOWARDS ANOTHER
SYSTEM AND AWAY FROM THE DRY GFS.

&&

.AVIATION /09Z MONDAY THROUGH FRIDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH TUESDAY/...

TODAY...HIGH CONFIDENCE. DRIZZLE OR A FEW FLURRIES POSSIBLE
ACROSS EAST MASS TERMINALS. OTHERWISE ANY VFR CIGS WILL DROP TO
MVFR CONDITIONS THROUGHOUT THE DAY.

TONIGHT...MODERATE CONFIDENCE. MAINLY MVFR CONDITIONS CONTINUE IN
SCATTERED LIGHT SNOW SHOWERS. LIGHT FZRA POSSIBLE LATE MONDAY NIGHT
ACROSS NW MASSACHUSETTS.

TUESDAY...MODERATE CONFIDENCE. MVFR CONDITIONS MAY DROP TO IFR
WITHIN AND HEAVY RAIN FALL. VSBYS WILL BE REDUCED TO 5SM OR LESS
AS WELL.

KBOS TERMINAL...MODERATE CONFIDENCE. COULD SEE DRIZZLE LATER TODAY.

KBDL TERMINAL...MODERATE CONFIDENCE.

OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...

TUESDAY NIGHT INTO THURSDAY MORNING...MODERATE CONFIDENCE.
WIDESPREAD LOW END MVFR TO IFR CONDITIONS EXPECTED IN PERIODS OF
HEAVY SHOWERS/LOW CLOUDS AND FOG PATCHES.  A PERIOD OF SOUTHERLY
WIND GUSTS OF 30 TO 40 KNOTS EXPECTED ON THE COASTAL PLAIN WED
NIGHT.  LLWS ALSO A CONCERN FOR THE ENTIRE REGION WED INTO EARLY THU.

THURSDAY AFTERNOON INTO FRIDAY...MODERATE TO HIGH CONFIDENCE IN
MAINLY VFR.  HOWEVER...A PERIOD OF WESTERLY 30 TO 45 KNOT WIND GUSTS
POSSIBLE THU AFTERNOON AND EVENING.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH TUESDAY/...MODERATE TO HIGH CONFIDENCE.

HIGH PRESSURE ACROSS QUEBEC AND THE MARITIMES WILL RESULT IN
PERSISTENT NORTHEASTERLY TO EASTERLY WINDS ACROSS THE WATERS THROUGH
TODAY. THIS WILL BUILD SEAS TO 5FT ON THE EASTERN WATERS DESPITE
WIND GUSTS UP TO 20 KNOTS. HAVE CONTINUED SCA.

APPROACHING SURFACE LOW PRESSURE FROM THE MID-ATLANTIC TONIGHT WILL
HELP INCREASE AN EASTERLY LLJ OVER THE WATER TOMORROW. THIS WILL
BUILD THE SEAS BETWEEN 5-8 FT. COULD SEE WIND GUSTS BETWEEN 20-30
KTS AS THE FRONT PASSES. SCA HAS BEEN EXPANDED ACCORDINGLY.

OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...MODERATE CONFIDENCE

TUESDAY NIGHT...LONG FETCH EASTERLY FLOW WILL CONTINUE TO RESULT IN
SCA SEAS ACROSS THE OUTER-WATERS WITH HIGH PRESSURE MOVING EAST OF
THE CANADIAN MARITIMES.  WINDS SHOULD GENERALLY BE BELOW SMALL CRAFT
THRESHOLDS.

WEDNESDAY INTO EARLY THURSDAY...INTENSIFYING LOW PRESSURE PASSING
WELL TO OUR WEST WILL CAUSE WINDS TO TURN SOUTHERLY AND BECOME
GUSTY. SMALL CRAFT WIND GUSTS ARE A LOCK.  THE MAIN UNCERTAINTY IS
DO WE SEE SOUTHERLY GALES DEVELOP WED NIGHT.  STRONG LOW LEVEL JET
PRESENT...BUT WE WILL BE DEALING WITH AN INVERSION OVER THE
RELATIVELY COOL OCEAN.  REGARDLESS...STILL SHOULD SEE AT LEAST A
PERIOD OF NEAR GALE FORCE SOUTHERLY WIND GUSTS.

LATER THURSDAY INTO FRIDAY...A PERIOD OF WESTERLY GALE FORCE WIND
GUSTS APPEARS LIKELY IN THE COLD ADVECTION PATTERN BEHIND THE STORM
THU AFTERNOON AND NIGHT.  WINDS SHOULD DIMINISH SOME ON FRIDAY.

&&

.TIDES/COASTAL FLOODING...


HIGH ASTRONOMICAL TIDES OCCUR TUE AND WED.

EAST MASSACHUSETTS COAST:

TUESDAY...HIGH TIDE AT BOSTON WILL BE 11.6 FT AT MIDDAY. WINDS WILL
BE FROM THE EAST AT 10 TO 15 KNOTS...SO THERE WILL BE ONSHORE FLOW
DURING THIS HIGH TIDE.  WHILE THIS IS NOTHING TOO STRONG...GIVEN THE
HIGH ASTRO TIDE EXPECT SOME SPLASH OVER/MINOR COASTAL FLOODING.
CERTAINLY DO NOT EXPECT TO SEE ANY SIGNIFICANT ISSUES.

WEDNESDAY...HIGH TIDE AT BOSTON WILL BE 11.7 FT AT MIDDAY.  WINDS
WILL BE FROM THE SOUTHEAST NEAR 10 KNOTS BUT THERE WILL BE SOME
PRESSURE FALLS WITH INTENSIFYING LOW PRESSURE TO OUR WEST.  THIS
SHOULD BE ENOUGH FOR MORE SPLASH OVER/MINOR COASTAL FLOODING WITH
THE HIGH ASTRO TIDES.  HOWEVER...DO NOT EXPECT ANY SIGNIFICANT
PROBLEMS GIVEN WINDS/SEAS SHOULD BE HELD IN CHECK DURING THE TIME OF
HIGH TIDE.

SOUTH COAST:

WEDNESDAY EVENING...SOUTHERLY WINDS ARE EXPECTED AND ASTRONOMICAL
TIDES INCREASE ALONG THE SOUTH COAST. HIGH TIDE IN PROVIDENCE WILL
BE 5.2 FT THAT EVENING. 925 MB LLJ STRENGTHENS TO 55-65 KTS WHICH
COULD PUSH A 1 TO 2 FOOT SURGE UP ALONG THE SOUTH COAST DURING THE
TIME OF HIGH TIDE.  THE LOW LEVEL INVERSION WILL PROBABLY HOLD THE
STRONGEST WINDS JUST ABOVE THE GROUND...SO THINKING THE RISK IS FOR
SPLASH OVER AND MINOR COASTAL FLOODING.  THERE STILL IS A LOW RISK
FOR MODERATE COASTAL FLOODING...BUT THAT IS OFTEN HARD TO GET IN A
NON-TROPICAL SYSTEM ALONG THE SOUTH COAST.


&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 1 AM TO 7 PM EST TUESDAY FOR ANZ231-
     232-251-256.
     SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 7 PM EST
     TUESDAY FOR ANZ250-254.
     SMALL CRAFT ADVISORY FROM 10 PM THIS EVENING TO 7 PM EST
     TUESDAY FOR ANZ255.

&&

$$
SYNOPSIS...DUNTEN/FRANK
NEAR TERM...DUNTEN
SHORT TERM...DUNTEN
LONG TERM...FRANK
AVIATION...DUNTEN/FRANK
MARINE...DUNTEN/FRANK
TIDES/COASTAL FLOODING...FRANK



000
FXUS61 KBOX 220927
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
416 AM EST MON DEC 22 2014

.SYNOPSIS...

A WAVE OF LOW PRESSURE WILL BRING THE PERIODS OF WET WEATHER MAINLY
LATE TONIGHT INTO TUESDAY NIGHT...WHICH MAY BEGIN AS A BRIEF PERIOD
OF FROZEN PRECIPITATION ACROSS NORTHWEST MASSACHUSETTS.  A MUCH
STRONGER STORM PASSING WELL TO OUR WEST WEDNESDAY INTO CHRISTMAS
MORNING WILL BRING HEAVY RAIN...GUSTY WINDS AND MINOR COASTAL
FLOODING.  DRY WEATHER WITH ABOVE NORMAL TEMPERATURES EXPECTED
CHRISTMAS AFTERNOON INTO SATURDAY.  LOW PRESSURE MAY BRING A RETURN
TO UNSETTLED WEATHER BY NEXT SUNDAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPPER LEVEL RIDGE BUILDS AHEAD OF DIGGING MIDWEST TROUGH WITH
HIGH PRESSURE REMAINING ANCHORED OVER THE CANADIAN MARITIMES
THROUGH TONIGHT.

EASTERLY FLOW WILL CONTINUE ONSHORE ALLOWING FOR THE PROFILE TO
CONTINUE TO MOISTEN IN THE LOW LEVELS. IF THIS MOISTURE DEEPENS
ENOUGH THEN WE COULD SEE LIGHT SHOWERS DEVELOP ESP ACROSS THE MASS
EAST COASTLINE. OTHERWISE DRIZZLE MAY BE THE MAIN FACTOR AS THE
UPPER LEVELS ARE FAIRLY DRY. OVERALL TODAY WILL BE A COOL AND CLOUDY
DAY WITH HIGHS ONLY REACHING IN THE UPPER 30S TO LOW 40S AS CROSS
SECTIONS ARE VERY MOIST IN THE LOW LEVELS.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
TONIGHT INTO TOMORROW...

*LIGHT FREEZING RAIN IS POSSIBLE ACROSS THE INTERIOR NORTHWEST AND
  NORTHERN WORCESTER HILLS*

A WEAK AREA OF LOW PRESSURE DEVELOPS ALONG A WARM FRONT OFF THE MID
ATLANTIC...DRIFTING NORTHWARD TOWARD THE AREA. THIS LOW REMAINS WEAK
AS THE WARM FRONT MOVES SLOWLY NORTHWARD TONIGHT INTO TOMORROW.
DECENT WARM ADVECTION AHEAD OF THIS WAVE WITH SEVERAL HI-RES
GUIDANCE MODELS SHOWS A POTENTIAL FOR COLD AIR DAMMING ACROSS THE
INTERIOR INTO TUESDAY MORNING.  BIGGEST QUESTION WILL BE THE
MOISTURE POTENTIAL...IS THERE ENOUGH TO DEVELOP PRECIP ESP TONIGHT?
GUIDANCE DOES SHOW ENOUGH LIFT AHEAD OF APPROACHING SURFACE LOW PER
THE GFS/EC SO ANTICIPATE PRECIP TO DEVELOP AND OVERSPREAD ACROSS
SOUTHERN NEW ENGLAND. IF THIS PLAYS OUT WITH COLD AIR DAMMING AND
WARM AIR ADVECTION...THEN WE COULD SEE FREEZING RAIN/DRIZZLE ACROSS
THE INTERIOR NORTHWEST AND NORTHERN WORCESTER HILLS VERY LATE
TONIGHT INTO TUESDAY MORNING. A WINTER WEATHER ADVISORY MAY BE
NEEDED.

AS SURFACE LOW CONTINUES TO MOVE NORTHWARD...AND HIGH PRESSURE OVER
EASTERN CANADA...ANTICIPATE AN INCREASING LLJ. THIS SOUTHEASTERLY
JET WILL CONTINUE TO FEED MOISTURE INTO THE REGION AND WITH
SOUNDINGS SHOW A VERY SATURATED PROFILE COULD SEE NUMEROUS SHOWERS
WITH PERHAPS A FEW HEAVY DOWNPOURS. NOTICED GUIDANCE HAS
INCREASED THE QPF OVER THE PAST FEW DAYS. AS THE WEAK SURFACE LOW
MOVES NORTH OF SOUTHERN NEW ENGLAND...WARM FRONT WILL LIFT
NORTHWARD SO ALL PRECIP BY THE LATE MORNING WILL BE IN THE LIQUID
FORM.

WE COULD ALSO SEE SOME MINOR COASTAL FLOODING CONCERNS ON TUESDAY
WITH DUE EASTERLY FLOW INCREASING TO ABOUT 20 TO 25 MPH.  SEE BELOW
FOR MORE DETAILS.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...

HIGHLIGHTS...

* PERIODS OF RAIN TUE NIGHT INTO XMAS MORNING WILL BE HEAVY AT TIMES
* DRY BY XMAS AFTERNOON BUT WINDY
* TEMPS AROUND 60 FOR SOME LATE WED INTO CHRISTMAS MORNING
* DRY BUT ABOVE NORMAL TEMPS CONTINUE FRI AND SAT
* UNSETTLED WEATHER MAY RETURN BY SUN BUT LOW CONFIDENCE

DETAILS...

TUESDAY NIGHT INTO CHRISTMAS...

STRONG SHORTWAVE WILL DIG ACROSS THE CENTRAL U.S. AND ALLOW DEEP
SOUTH TO SOUTHWEST FLOW ALOFT ACROSS SOUTHERN NEW ENGLAND.  THIS
WILL SEND AND ANOMALOUS MILD AIRMASS INTO SOUTHERN NEW ENGLAND FOR
LATE DECEMBER.  GEFS SHOWING PWATS 4 TO 5 STANDARD DEVIATIONS ABOVE
NORMAL BY WED NIGHT ACROSS OUR REGION.  WHILE HEAVY RAIN IS STILL
EXPECTED...THE MODELS HAVE CUT DOWN ON THE QPF IN THE LAST FEW RUNS.
THE MAIN LOW STILL PASSES WELL TO OUR WEST ACROSS GREAT LAKES...BUT
THEIR SLOWER AND WEAKER WITH SECONDARY DEVELOPMENT ACROSS OUR
REGION.  THIS RESULTS IN A WEAKER LOW LEVEL JET...HENCE LESS QPF.
GIVEN ANOMALOUS PWATS IN PLACE...DO NOT WANT TO COMPLETELY LET OUR
GUARD DOWN WITH THE POTENTIAL FOR FLOODING...BUT DOES APPEAR
SOMEWHAT LESS OF A RISK THAN YESTERDAY.  NONETHELESS...STILL EXPECT
TYPICAL NUISANCE POOR DRAINAGE STREET FLOODING.

AS FOR TIMING...SOUTHERLY FLOW ALOFT WILL RESULT IN SCATTERED
SHOWERS TUE NIGHT.  BULK OF THE RAIN WILL OCCUR WED INTO EARLY
CHRISTMAS DAY WHEN STRONGEST FORCING COINCIDES HIGH PWAT AIRMASS.
SOME OF THIS RAIN WILL BE HEAVY AT TIMES MAY RESULT IN NUISANCE POOR
DRAINAGE STREET FLOODING.  STILL A LOW RISK FOR MORE SIGNIFICANT
FLOODING GIVEN EXTREMELY HIGH PWATS...BUT SLOWER DEVELOPMENT OF
SECONDARY LOW PRESSURE MAY BE A LIMITING FACTOR.  REGARDLESS...
EXPECT 1 TO 3 INCHES OF RAIN.  WILL CONTINUE TO MENTION A SLIGHT
CHANCE OF THUNDER WITH SHOWALTER INDICES NEAR ZERO.

THE BULK OF THE RAIN SHOULD COME TO AN END CHRISTMAS MORNING WITH
TEMPS PROBABLY AROUND 60 FOR MUCH OF THE REGION.  WHILE GUSTY
SOUTHERLY WINDS ARE EXPECTED WED NIGHT...INVERSION AND WEAKER LOW
LEVEL JET WILL PROBABLY KEEP MOST AREAS BELOW ADVISORY CRITERIA.
STILL HAVE TO WATCH FOR A SMALL WINDOW ON THE COASTAL PLAIN ESP IF
TEMPS CAN EXCEED 60...BUT HIGHER CONFIDENCE IN WIND ON CHRISTMAS
AFTERNOON AND EVENING BEHIND THE SYSTEM.  INCREASING WESTERLY WIND
ALOFT AND STEEPENING LAPSE RATES WILL BRING THE POTENTIAL FOR THESE
WINDS.  DECENT SHOT AT A PERIOD OF 35 TO 50 MPH GUSTS BEHIND THIS
SYSTEM CHRISTMAS AFTERNOON AND EVENING.  WHILE THE GFS IS AN
OUTLIER...IT WOULD EVEN SUGGEST THE POTENTIAL FOR HIGH WIND CRITERIA
TO BE MET WITH 70 KNOTS AT 850 MB.  THAT MAY BE OVERDONE...BUT
SOMETHING WILL HAVE TO KEEP AN EYE ON THE NEXT FEW DAYS.

FRIDAY AND SATURDAY...

UPPER LEVEL RIDGE OFF THE SOUTHEAST COAST WILL KEEP KEEP US IN MILD
SOUTHWEST FLOW ALOFT.  DRY WEATHER EXPECTED WITH FORCING FOR ANY
PRECIPITATION WILL TO OUR NORTHWEST.  HIGHS MAINLY IN THE 40S TO
LOWER 50S.

SUNDAY...

CONFIDENCE IN THE FORECAST GOES DOWN CONSIDERABLE OVER THIS TIME.
DEVELOPING UPPER LEVEL RIDGING INTO ALASKA WILL SEND THE POLAR JET
SOUTHWARD INTO THE CENTRAL U.S.  AT THE SAME TIME...UPPER LEVEL
RIDGE OFF THE SOUTHEAST COAST WILL TRY TO HANG TOUGH.  THE GFS
INSISTS ON DRY AND COLDER WEATHER ARRIVING...BUT WERE NOT CONVINCED.
GIVEN THE SOUTHEAST RIDGE IT MAY HOLD THE COLD AIR UP AND ALLOW
DEVELOPING LOW PRESSURE TO TRACK NEAR NEW ENGLAND SUN AND SUN NIGHT.
THIS COULD BRING RAIN OR SNOW DEPENDING ON ITS TRACK...OBVIOUSLY A
WEEK OUT SO PLENTY OF UNCERTAINTY BUT WOULD LEAN TOWARDS ANOTHER
SYSTEM AND AWAY FROM THE DRY GFS.

&&

.AVIATION /09Z MONDAY THROUGH FRIDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH TUESDAY/...

TODAY...HIGH CONFIDENCE. DRIZZLE OR A FEW FLURRIES POSSIBLE
ACROSS EAST MASS TERMINALS. OTHERWISE ANY VFR CIGS WILL DROP TO
MVFR CONDITIONS THROUGHOUT THE DAY.

TONIGHT...MODERATE CONFIDENCE. MAINLY MVFR CONDITIONS CONTINUE IN
SCATTERED LIGHT SNOW SHOWERS. LIGHT FZRA POSSIBLE LATE MONDAY NIGHT
ACROSS NW MASSACHUSETTS.

TUESDAY...MODERATE CONFIDENCE. MVFR CONDITIONS MAY DROP TO IFR
WITHIN AND HEAVY RAIN FALL. VSBYS WILL BE REDUCED TO 5SM OR LESS
AS WELL.

KBOS TERMINAL...MODERATE CONFIDENCE. COULD SEE DRIZZLE LATER TODAY.

KBDL TERMINAL...MODERATE CONFIDENCE.

OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...

TUESDAY NIGHT INTO THURSDAY MORNING...MODERATE CONFIDENCE.
WIDESPREAD LOW END MVFR TO IFR CONDITIONS EXPECTED IN PERIODS OF
HEAVY SHOWERS/LOW CLOUDS AND FOG PATCHES.  A PERIOD OF SOUTHERLY
WIND GUSTS OF 30 TO 40 KNOTS EXPECTED ON THE COASTAL PLAIN WED
NIGHT.  LLWS ALSO A CONCERN FOR THE ENTIRE REGION WED INTO EARLY THU.

THURSDAY AFTERNOON INTO FRIDAY...MODERATE TO HIGH CONFIDENCE IN
MAINLY VFR.  HOWEVER...A PERIOD OF WESTERLY 30 TO 45 KNOT WIND GUSTS
POSSIBLE THU AFTERNOON AND EVENING.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH TUESDAY/...MODERATE TO HIGH CONFIDENCE.

HIGH PRESSURE ACROSS QUEBEC AND THE MARITIMES WILL RESULT IN
PERSISTENT NORTHEASTERLY TO EASTERLY WINDS ACROSS THE WATERS THROUGH
TODAY. THIS WILL BUILD SEAS TO 5FT ON THE EASTERN WATERS DESPITE
WIND GUSTS UP TO 20 KNOTS. HAVE CONTINUED SCA.

APPROACHING SURFACE LOW PRESSURE FROM THE MID-ATLANTIC TONIGHT WILL
HELP INCREASE AN EASTERLY LLJ OVER THE WATER TOMORROW. THIS WILL
BUILD THE SEAS BETWEEN 5-8 FT. COULD SEE WIND GUSTS BETWEEN 20-30
KTS AS THE FRONT PASSES. SCA HAS BEEN EXPANDED ACCORDINGLY.

OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...MODERATE CONFIDENCE

TUESDAY NIGHT...LONG FETCH EASTERLY FLOW WILL CONTINUE TO RESULT IN
SCA SEAS ACROSS THE OUTER-WATERS WITH HIGH PRESSURE MOVING EAST OF
THE CANADIAN MARITIMES.  WINDS SHOULD GENERALLY BE BELOW SMALL CRAFT
THRESHOLDS.

WEDNESDAY INTO EARLY THURSDAY...INTENSIFYING LOW PRESSURE PASSING
WELL TO OUR WEST WILL CAUSE WINDS TO TURN SOUTHERLY AND BECOME
GUSTY. SMALL CRAFT WIND GUSTS ARE A LOCK.  THE MAIN UNCERTAINTY IS
DO WE SEE SOUTHERLY GALES DEVELOP WED NIGHT.  STRONG LOW LEVEL JET
PRESENT...BUT WE WILL BE DEALING WITH AN INVERSION OVER THE
RELATIVELY COOL OCEAN.  REGARDLESS...STILL SHOULD SEE AT LEAST A
PERIOD OF NEAR GALE FORCE SOUTHERLY WIND GUSTS.

LATER THURSDAY INTO FRIDAY...A PERIOD OF WESTERLY GALE FORCE WIND
GUSTS APPEARS LIKELY IN THE COLD ADVECTION PATTERN BEHIND THE STORM
THU AFTERNOON AND NIGHT.  WINDS SHOULD DIMINISH SOME ON FRIDAY.

&&

.TIDES/COASTAL FLOODING...


HIGH ASTRONOMICAL TIDES OCCUR TUE AND WED.

EAST MASSACHUSETTS COAST:

TUESDAY...HIGH TIDE AT BOSTON WILL BE 11.6 FT AT MIDDAY. WINDS WILL
BE FROM THE EAST AT 10 TO 15 KNOTS...SO THERE WILL BE ONSHORE FLOW
DURING THIS HIGH TIDE.  WHILE THIS IS NOTHING TOO STRONG...GIVEN THE
HIGH ASTRO TIDE EXPECT SOME SPLASH OVER/MINOR COASTAL FLOODING.
CERTAINLY DO NOT EXPECT TO SEE ANY SIGNIFICANT ISSUES.

WEDNESDAY...HIGH TIDE AT BOSTON WILL BE 11.7 FT AT MIDDAY.  WINDS
WILL BE FROM THE SOUTHEAST NEAR 10 KNOTS BUT THERE WILL BE SOME
PRESSURE FALLS WITH INTENSIFYING LOW PRESSURE TO OUR WEST.  THIS
SHOULD BE ENOUGH FOR MORE SPLASH OVER/MINOR COASTAL FLOODING WITH
THE HIGH ASTRO TIDES.  HOWEVER...DO NOT EXPECT ANY SIGNIFICANT
PROBLEMS GIVEN WINDS/SEAS SHOULD BE HELD IN CHECK DURING THE TIME OF
HIGH TIDE.

SOUTH COAST:

WEDNESDAY EVENING...SOUTHERLY WINDS ARE EXPECTED AND ASTRONOMICAL
TIDES INCREASE ALONG THE SOUTH COAST. HIGH TIDE IN PROVIDENCE WILL
BE 5.2 FT THAT EVENING. 925 MB LLJ STRENGTHENS TO 55-65 KTS WHICH
COULD PUSH A 1 TO 2 FOOT SURGE UP ALONG THE SOUTH COAST DURING THE
TIME OF HIGH TIDE.  THE LOW LEVEL INVERSION WILL PROBABLY HOLD THE
STRONGEST WINDS JUST ABOVE THE GROUND...SO THINKING THE RISK IS FOR
SPLASH OVER AND MINOR COASTAL FLOODING.  THERE STILL IS A LOW RISK
FOR MODERATE COASTAL FLOODING...BUT THAT IS OFTEN HARD TO GET IN A
NON-TROPICAL SYSTEM ALONG THE SOUTH COAST.


&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 1 AM TO 7 PM EST TUESDAY FOR ANZ231-
     232-251-256.
     SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 7 PM EST
     TUESDAY FOR ANZ250-254.
     SMALL CRAFT ADVISORY FROM 10 PM THIS EVENING TO 7 PM EST
     TUESDAY FOR ANZ255.

&&

$$
SYNOPSIS...FRANK/DUNTEN
NEAR TERM...DUNTEN
SHORT TERM...DUNTEN
LONG TERM...FRANK
AVIATION...FRANK/DUNTEN
MARINE...FRANK/DUNTEN
TIDES/COASTAL FLOODING...FRANK



000
FXUS61 KBOX 220927
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
416 AM EST MON DEC 22 2014

.SYNOPSIS...

A WAVE OF LOW PRESSURE WILL BRING THE PERIODS OF WET WEATHER MAINLY
LATE TONIGHT INTO TUESDAY NIGHT...WHICH MAY BEGIN AS A BRIEF PERIOD
OF FROZEN PRECIPITATION ACROSS NORTHWEST MASSACHUSETTS.  A MUCH
STRONGER STORM PASSING WELL TO OUR WEST WEDNESDAY INTO CHRISTMAS
MORNING WILL BRING HEAVY RAIN...GUSTY WINDS AND MINOR COASTAL
FLOODING.  DRY WEATHER WITH ABOVE NORMAL TEMPERATURES EXPECTED
CHRISTMAS AFTERNOON INTO SATURDAY.  LOW PRESSURE MAY BRING A RETURN
TO UNSETTLED WEATHER BY NEXT SUNDAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPPER LEVEL RIDGE BUILDS AHEAD OF DIGGING MIDWEST TROUGH WITH
HIGH PRESSURE REMAINING ANCHORED OVER THE CANADIAN MARITIMES
THROUGH TONIGHT.

EASTERLY FLOW WILL CONTINUE ONSHORE ALLOWING FOR THE PROFILE TO
CONTINUE TO MOISTEN IN THE LOW LEVELS. IF THIS MOISTURE DEEPENS
ENOUGH THEN WE COULD SEE LIGHT SHOWERS DEVELOP ESP ACROSS THE MASS
EAST COASTLINE. OTHERWISE DRIZZLE MAY BE THE MAIN FACTOR AS THE
UPPER LEVELS ARE FAIRLY DRY. OVERALL TODAY WILL BE A COOL AND CLOUDY
DAY WITH HIGHS ONLY REACHING IN THE UPPER 30S TO LOW 40S AS CROSS
SECTIONS ARE VERY MOIST IN THE LOW LEVELS.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
TONIGHT INTO TOMORROW...

*LIGHT FREEZING RAIN IS POSSIBLE ACROSS THE INTERIOR NORTHWEST AND
  NORTHERN WORCESTER HILLS*

A WEAK AREA OF LOW PRESSURE DEVELOPS ALONG A WARM FRONT OFF THE MID
ATLANTIC...DRIFTING NORTHWARD TOWARD THE AREA. THIS LOW REMAINS WEAK
AS THE WARM FRONT MOVES SLOWLY NORTHWARD TONIGHT INTO TOMORROW.
DECENT WARM ADVECTION AHEAD OF THIS WAVE WITH SEVERAL HI-RES
GUIDANCE MODELS SHOWS A POTENTIAL FOR COLD AIR DAMMING ACROSS THE
INTERIOR INTO TUESDAY MORNING.  BIGGEST QUESTION WILL BE THE
MOISTURE POTENTIAL...IS THERE ENOUGH TO DEVELOP PRECIP ESP TONIGHT?
GUIDANCE DOES SHOW ENOUGH LIFT AHEAD OF APPROACHING SURFACE LOW PER
THE GFS/EC SO ANTICIPATE PRECIP TO DEVELOP AND OVERSPREAD ACROSS
SOUTHERN NEW ENGLAND. IF THIS PLAYS OUT WITH COLD AIR DAMMING AND
WARM AIR ADVECTION...THEN WE COULD SEE FREEZING RAIN/DRIZZLE ACROSS
THE INTERIOR NORTHWEST AND NORTHERN WORCESTER HILLS VERY LATE
TONIGHT INTO TUESDAY MORNING. A WINTER WEATHER ADVISORY MAY BE
NEEDED.

AS SURFACE LOW CONTINUES TO MOVE NORTHWARD...AND HIGH PRESSURE OVER
EASTERN CANADA...ANTICIPATE AN INCREASING LLJ. THIS SOUTHEASTERLY
JET WILL CONTINUE TO FEED MOISTURE INTO THE REGION AND WITH
SOUNDINGS SHOW A VERY SATURATED PROFILE COULD SEE NUMEROUS SHOWERS
WITH PERHAPS A FEW HEAVY DOWNPOURS. NOTICED GUIDANCE HAS
INCREASED THE QPF OVER THE PAST FEW DAYS. AS THE WEAK SURFACE LOW
MOVES NORTH OF SOUTHERN NEW ENGLAND...WARM FRONT WILL LIFT
NORTHWARD SO ALL PRECIP BY THE LATE MORNING WILL BE IN THE LIQUID
FORM.

WE COULD ALSO SEE SOME MINOR COASTAL FLOODING CONCERNS ON TUESDAY
WITH DUE EASTERLY FLOW INCREASING TO ABOUT 20 TO 25 MPH.  SEE BELOW
FOR MORE DETAILS.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...

HIGHLIGHTS...

* PERIODS OF RAIN TUE NIGHT INTO XMAS MORNING WILL BE HEAVY AT TIMES
* DRY BY XMAS AFTERNOON BUT WINDY
* TEMPS AROUND 60 FOR SOME LATE WED INTO CHRISTMAS MORNING
* DRY BUT ABOVE NORMAL TEMPS CONTINUE FRI AND SAT
* UNSETTLED WEATHER MAY RETURN BY SUN BUT LOW CONFIDENCE

DETAILS...

TUESDAY NIGHT INTO CHRISTMAS...

STRONG SHORTWAVE WILL DIG ACROSS THE CENTRAL U.S. AND ALLOW DEEP
SOUTH TO SOUTHWEST FLOW ALOFT ACROSS SOUTHERN NEW ENGLAND.  THIS
WILL SEND AND ANOMALOUS MILD AIRMASS INTO SOUTHERN NEW ENGLAND FOR
LATE DECEMBER.  GEFS SHOWING PWATS 4 TO 5 STANDARD DEVIATIONS ABOVE
NORMAL BY WED NIGHT ACROSS OUR REGION.  WHILE HEAVY RAIN IS STILL
EXPECTED...THE MODELS HAVE CUT DOWN ON THE QPF IN THE LAST FEW RUNS.
THE MAIN LOW STILL PASSES WELL TO OUR WEST ACROSS GREAT LAKES...BUT
THEIR SLOWER AND WEAKER WITH SECONDARY DEVELOPMENT ACROSS OUR
REGION.  THIS RESULTS IN A WEAKER LOW LEVEL JET...HENCE LESS QPF.
GIVEN ANOMALOUS PWATS IN PLACE...DO NOT WANT TO COMPLETELY LET OUR
GUARD DOWN WITH THE POTENTIAL FOR FLOODING...BUT DOES APPEAR
SOMEWHAT LESS OF A RISK THAN YESTERDAY.  NONETHELESS...STILL EXPECT
TYPICAL NUISANCE POOR DRAINAGE STREET FLOODING.

AS FOR TIMING...SOUTHERLY FLOW ALOFT WILL RESULT IN SCATTERED
SHOWERS TUE NIGHT.  BULK OF THE RAIN WILL OCCUR WED INTO EARLY
CHRISTMAS DAY WHEN STRONGEST FORCING COINCIDES HIGH PWAT AIRMASS.
SOME OF THIS RAIN WILL BE HEAVY AT TIMES MAY RESULT IN NUISANCE POOR
DRAINAGE STREET FLOODING.  STILL A LOW RISK FOR MORE SIGNIFICANT
FLOODING GIVEN EXTREMELY HIGH PWATS...BUT SLOWER DEVELOPMENT OF
SECONDARY LOW PRESSURE MAY BE A LIMITING FACTOR.  REGARDLESS...
EXPECT 1 TO 3 INCHES OF RAIN.  WILL CONTINUE TO MENTION A SLIGHT
CHANCE OF THUNDER WITH SHOWALTER INDICES NEAR ZERO.

THE BULK OF THE RAIN SHOULD COME TO AN END CHRISTMAS MORNING WITH
TEMPS PROBABLY AROUND 60 FOR MUCH OF THE REGION.  WHILE GUSTY
SOUTHERLY WINDS ARE EXPECTED WED NIGHT...INVERSION AND WEAKER LOW
LEVEL JET WILL PROBABLY KEEP MOST AREAS BELOW ADVISORY CRITERIA.
STILL HAVE TO WATCH FOR A SMALL WINDOW ON THE COASTAL PLAIN ESP IF
TEMPS CAN EXCEED 60...BUT HIGHER CONFIDENCE IN WIND ON CHRISTMAS
AFTERNOON AND EVENING BEHIND THE SYSTEM.  INCREASING WESTERLY WIND
ALOFT AND STEEPENING LAPSE RATES WILL BRING THE POTENTIAL FOR THESE
WINDS.  DECENT SHOT AT A PERIOD OF 35 TO 50 MPH GUSTS BEHIND THIS
SYSTEM CHRISTMAS AFTERNOON AND EVENING.  WHILE THE GFS IS AN
OUTLIER...IT WOULD EVEN SUGGEST THE POTENTIAL FOR HIGH WIND CRITERIA
TO BE MET WITH 70 KNOTS AT 850 MB.  THAT MAY BE OVERDONE...BUT
SOMETHING WILL HAVE TO KEEP AN EYE ON THE NEXT FEW DAYS.

FRIDAY AND SATURDAY...

UPPER LEVEL RIDGE OFF THE SOUTHEAST COAST WILL KEEP KEEP US IN MILD
SOUTHWEST FLOW ALOFT.  DRY WEATHER EXPECTED WITH FORCING FOR ANY
PRECIPITATION WILL TO OUR NORTHWEST.  HIGHS MAINLY IN THE 40S TO
LOWER 50S.

SUNDAY...

CONFIDENCE IN THE FORECAST GOES DOWN CONSIDERABLE OVER THIS TIME.
DEVELOPING UPPER LEVEL RIDGING INTO ALASKA WILL SEND THE POLAR JET
SOUTHWARD INTO THE CENTRAL U.S.  AT THE SAME TIME...UPPER LEVEL
RIDGE OFF THE SOUTHEAST COAST WILL TRY TO HANG TOUGH.  THE GFS
INSISTS ON DRY AND COLDER WEATHER ARRIVING...BUT WERE NOT CONVINCED.
GIVEN THE SOUTHEAST RIDGE IT MAY HOLD THE COLD AIR UP AND ALLOW
DEVELOPING LOW PRESSURE TO TRACK NEAR NEW ENGLAND SUN AND SUN NIGHT.
THIS COULD BRING RAIN OR SNOW DEPENDING ON ITS TRACK...OBVIOUSLY A
WEEK OUT SO PLENTY OF UNCERTAINTY BUT WOULD LEAN TOWARDS ANOTHER
SYSTEM AND AWAY FROM THE DRY GFS.

&&

.AVIATION /09Z MONDAY THROUGH FRIDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH TUESDAY/...

TODAY...HIGH CONFIDENCE. DRIZZLE OR A FEW FLURRIES POSSIBLE
ACROSS EAST MASS TERMINALS. OTHERWISE ANY VFR CIGS WILL DROP TO
MVFR CONDITIONS THROUGHOUT THE DAY.

TONIGHT...MODERATE CONFIDENCE. MAINLY MVFR CONDITIONS CONTINUE IN
SCATTERED LIGHT SNOW SHOWERS. LIGHT FZRA POSSIBLE LATE MONDAY NIGHT
ACROSS NW MASSACHUSETTS.

TUESDAY...MODERATE CONFIDENCE. MVFR CONDITIONS MAY DROP TO IFR
WITHIN AND HEAVY RAIN FALL. VSBYS WILL BE REDUCED TO 5SM OR LESS
AS WELL.

KBOS TERMINAL...MODERATE CONFIDENCE. COULD SEE DRIZZLE LATER TODAY.

KBDL TERMINAL...MODERATE CONFIDENCE.

OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...

TUESDAY NIGHT INTO THURSDAY MORNING...MODERATE CONFIDENCE.
WIDESPREAD LOW END MVFR TO IFR CONDITIONS EXPECTED IN PERIODS OF
HEAVY SHOWERS/LOW CLOUDS AND FOG PATCHES.  A PERIOD OF SOUTHERLY
WIND GUSTS OF 30 TO 40 KNOTS EXPECTED ON THE COASTAL PLAIN WED
NIGHT.  LLWS ALSO A CONCERN FOR THE ENTIRE REGION WED INTO EARLY THU.

THURSDAY AFTERNOON INTO FRIDAY...MODERATE TO HIGH CONFIDENCE IN
MAINLY VFR.  HOWEVER...A PERIOD OF WESTERLY 30 TO 45 KNOT WIND GUSTS
POSSIBLE THU AFTERNOON AND EVENING.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH TUESDAY/...MODERATE TO HIGH CONFIDENCE.

HIGH PRESSURE ACROSS QUEBEC AND THE MARITIMES WILL RESULT IN
PERSISTENT NORTHEASTERLY TO EASTERLY WINDS ACROSS THE WATERS THROUGH
TODAY. THIS WILL BUILD SEAS TO 5FT ON THE EASTERN WATERS DESPITE
WIND GUSTS UP TO 20 KNOTS. HAVE CONTINUED SCA.

APPROACHING SURFACE LOW PRESSURE FROM THE MID-ATLANTIC TONIGHT WILL
HELP INCREASE AN EASTERLY LLJ OVER THE WATER TOMORROW. THIS WILL
BUILD THE SEAS BETWEEN 5-8 FT. COULD SEE WIND GUSTS BETWEEN 20-30
KTS AS THE FRONT PASSES. SCA HAS BEEN EXPANDED ACCORDINGLY.

OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...MODERATE CONFIDENCE

TUESDAY NIGHT...LONG FETCH EASTERLY FLOW WILL CONTINUE TO RESULT IN
SCA SEAS ACROSS THE OUTER-WATERS WITH HIGH PRESSURE MOVING EAST OF
THE CANADIAN MARITIMES.  WINDS SHOULD GENERALLY BE BELOW SMALL CRAFT
THRESHOLDS.

WEDNESDAY INTO EARLY THURSDAY...INTENSIFYING LOW PRESSURE PASSING
WELL TO OUR WEST WILL CAUSE WINDS TO TURN SOUTHERLY AND BECOME
GUSTY. SMALL CRAFT WIND GUSTS ARE A LOCK.  THE MAIN UNCERTAINTY IS
DO WE SEE SOUTHERLY GALES DEVELOP WED NIGHT.  STRONG LOW LEVEL JET
PRESENT...BUT WE WILL BE DEALING WITH AN INVERSION OVER THE
RELATIVELY COOL OCEAN.  REGARDLESS...STILL SHOULD SEE AT LEAST A
PERIOD OF NEAR GALE FORCE SOUTHERLY WIND GUSTS.

LATER THURSDAY INTO FRIDAY...A PERIOD OF WESTERLY GALE FORCE WIND
GUSTS APPEARS LIKELY IN THE COLD ADVECTION PATTERN BEHIND THE STORM
THU AFTERNOON AND NIGHT.  WINDS SHOULD DIMINISH SOME ON FRIDAY.

&&

.TIDES/COASTAL FLOODING...


HIGH ASTRONOMICAL TIDES OCCUR TUE AND WED.

EAST MASSACHUSETTS COAST:

TUESDAY...HIGH TIDE AT BOSTON WILL BE 11.6 FT AT MIDDAY. WINDS WILL
BE FROM THE EAST AT 10 TO 15 KNOTS...SO THERE WILL BE ONSHORE FLOW
DURING THIS HIGH TIDE.  WHILE THIS IS NOTHING TOO STRONG...GIVEN THE
HIGH ASTRO TIDE EXPECT SOME SPLASH OVER/MINOR COASTAL FLOODING.
CERTAINLY DO NOT EXPECT TO SEE ANY SIGNIFICANT ISSUES.

WEDNESDAY...HIGH TIDE AT BOSTON WILL BE 11.7 FT AT MIDDAY.  WINDS
WILL BE FROM THE SOUTHEAST NEAR 10 KNOTS BUT THERE WILL BE SOME
PRESSURE FALLS WITH INTENSIFYING LOW PRESSURE TO OUR WEST.  THIS
SHOULD BE ENOUGH FOR MORE SPLASH OVER/MINOR COASTAL FLOODING WITH
THE HIGH ASTRO TIDES.  HOWEVER...DO NOT EXPECT ANY SIGNIFICANT
PROBLEMS GIVEN WINDS/SEAS SHOULD BE HELD IN CHECK DURING THE TIME OF
HIGH TIDE.

SOUTH COAST:

WEDNESDAY EVENING...SOUTHERLY WINDS ARE EXPECTED AND ASTRONOMICAL
TIDES INCREASE ALONG THE SOUTH COAST. HIGH TIDE IN PROVIDENCE WILL
BE 5.2 FT THAT EVENING. 925 MB LLJ STRENGTHENS TO 55-65 KTS WHICH
COULD PUSH A 1 TO 2 FOOT SURGE UP ALONG THE SOUTH COAST DURING THE
TIME OF HIGH TIDE.  THE LOW LEVEL INVERSION WILL PROBABLY HOLD THE
STRONGEST WINDS JUST ABOVE THE GROUND...SO THINKING THE RISK IS FOR
SPLASH OVER AND MINOR COASTAL FLOODING.  THERE STILL IS A LOW RISK
FOR MODERATE COASTAL FLOODING...BUT THAT IS OFTEN HARD TO GET IN A
NON-TROPICAL SYSTEM ALONG THE SOUTH COAST.


&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 1 AM TO 7 PM EST TUESDAY FOR ANZ231-
     232-251-256.
     SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 7 PM EST
     TUESDAY FOR ANZ250-254.
     SMALL CRAFT ADVISORY FROM 10 PM THIS EVENING TO 7 PM EST
     TUESDAY FOR ANZ255.

&&

$$
SYNOPSIS...FRANK/DUNTEN
NEAR TERM...DUNTEN
SHORT TERM...DUNTEN
LONG TERM...FRANK
AVIATION...FRANK/DUNTEN
MARINE...FRANK/DUNTEN
TIDES/COASTAL FLOODING...FRANK




000
FXUS61 KBOX 220916
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
416 AM EST MON DEC 22 2014

.SYNOPSIS...

A WAVE OF LOW PRESSURE WILL BRING THE PERIODS OF WET WEATHER MAINLY
LATE TONIGHT INTO TUESDAY NIGHT...WHICH MAY BEGIN AS A BRIEF PERIOD
OF FROZEN PRECIPITATION ACROSS NORTHWEST MASSACHUSETTS.  A MUCH
STRONGER STORM PASSING WELL TO OUR WEST WEDNESDAY INTO CHRISTMAS
MORNING WILL BRING HEAVY RAIN...GUSTY WINDS AND MINOR COASTAL
FLOODING.  DRY WEATHER WITH ABOVE NORMAL TEMPERATURES EXPECTED
CHRISTMAS AFTERNOON INTO SATURDAY.  LOW PRESSURE MAY BRING A RETURN
TO UNSETTLED WEATHER BY WEDNESDAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPPER LEVEL RIDGE BUILDS AHEAD OF DIGGING MIDWEST TROUGH WITH
HIGH PRESSURE REMAINING ANCHORED OVER THE CANADIAN MARITIMES
THROUGH TONIGHT.

EASTERLY FLOW WILL CONTINUE ONSHORE ALLOWING FOR THE PROFILE TO
CONTINUE TO MOISTEN IN THE LOW LEVELS. IF THIS MOISTURE DEEPENS
ENOUGH THEN WE COULD SEE LIGHT SHOWERS DEVELOP ESP ACROSS THE MASS
EAST COASTLINE. OTHERWISE DRIZZLE MAY BE THE MAIN FACTOR AS THE
UPPER LEVELS ARE FAIRLY DRY. OVERALL TODAY WILL BE A COOL AND CLOUDY
DAY WITH HIGHS ONLY REACHING IN THE UPPER 30S TO LOW 40S AS CROSS
SECTIONS ARE VERY MOIST IN THE LOW LEVELS.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
TONIGHT INTO TOMORROW...

*LIGHT FREEZING RAIN IS POSSIBLE ACROSS THE INTERIOR NORTHWEST AND
  NORTHERN WORCESTER HILLS*

A WEAK AREA OF LOW PRESSURE DEVELOPS ALONG A WARM FRONT OFF THE MID
ATLANTIC...DRIFTING NORTHWARD TOWARD THE AREA. THIS LOW REMAINS WEAK
AS THE WARM FRONT MOVES SLOWLY NORTHWARD TONIGHT INTO TOMORROW.
DECENT WARM ADVECTION AHEAD OF THIS WAVE WITH SEVERAL HI-RES
GUIDANCE MODELS SHOWS A POTENTIAL FOR COLD AIR DAMMING ACROSS THE
INTERIOR INTO TUESDAY MORNING.  BIGGEST QUESTION WILL BE THE
MOISTURE POTENTIAL...IS THERE ENOUGH TO DEVELOP PRECIP ESP TONIGHT?
GUIDANCE DOES SHOW ENOUGH LIFT AHEAD OF APPROACHING SURFACE LOW PER
THE GFS/EC SO ANTICIPATE PRECIP TO DEVELOP AND OVERSPREAD ACROSS
SOUTHERN NEW ENGLAND. IF THIS PLAYS OUT WITH COLD AIR DAMMING AND
WARM AIR ADVECTION...THEN WE COULD SEE FREEZING RAIN/DRIZZLE ACROSS
THE INTERIOR NORTHWEST AND NORTHERN WORCESTER HILLS VERY LATE
TONIGHT INTO TUESDAY MORNING. A WINTER WEATHER ADVISORY MAY BE
NEEDED.

AS SURFACE LOW CONTINUES TO MOVE NORTHWARD...AND HIGH PRESSURE OVER
EASTERN CANADA...ANTICIPATE AN INCREASING LLJ. THIS SOUTHEASTERLY
JET WILL CONTINUE TO FEED MOISTURE INTO THE REGION AND WITH
SOUNDINGS SHOW A VERY SATURATED PROFILE COULD SEE NUMEROUS SHOWERS
WITH PERHAPS A FEW HEAVY DOWNPOURS. NOTICED GUIDANCE HAS
INCREASED THE QPF OVER THE PAST FEW DAYS. AS THE WEAK SURFACE LOW
MOVES NORTH OF SOUTHERN NEW ENGLAND...WARM FRONT WILL LIFT
NORTHWARD SO ALL PRECIP BY THE LATE MORNING WILL BE IN THE LIQUID
FORM.

WE COULD ALSO SEE SOME MINOR COASTAL FLOODING CONCERNS ON TUESDAY
WITH DUE EASTERLY FLOW INCREASING TO ABOUT 20 TO 25 MPH.  SEE BELOW
FOR MORE DETAILS.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...

HIGHLIGHTS...

* PERIODS OF RAIN TUE NIGHT INTO XMAS MORNING WILL BE HEAVY AT TIMES
* DRY BY XMAS AFTERNOON BUT WINDY
* TEMPS AROUND 60 FOR SOME LATE WED INTO CHRISTMAS MORNING
* DRY BUT ABOVE NORMAL TEMPS CONTINUE FRI AND SAT
* UNSETTLED WEATHER MAY RETURN BY SUN BUT LOW CONFIDENCE

DETAILS...

TUESDAY NIGHT INTO CHRISTMAS...

STRONG SHORTWAVE WILL DIG ACROSS THE CENTRAL U.S. AND ALLOW DEEP
SOUTH TO SOUTHWEST FLOW ALOFT ACROSS SOUTHERN NEW ENGLAND.  THIS
WILL SEND AND ANOMALOUS MILD AIRMASS INTO SOUTHERN NEW ENGLAND FOR
LATE DECEMBER.  GEFS SHOWING PWATS 4 TO 5 STANDARD DEVIATIONS ABOVE
NORMAL BY WED NIGHT ACROSS OUR REGION.  WHILE HEAVY RAIN IS STILL
EXPECTED...THE MODELS HAVE CUT DOWN ON THE QPF IN THE LAST FEW RUNS.
THE MAIN LOW STILL PASSES WELL TO OUR WEST ACROSS GREAT LAKES...BUT
THEIR SLOWER AND WEAKER WITH SECONDARY DEVELOPMENT ACROSS OUR
REGION.  THIS RESULTS IN A WEAKER LOW LEVEL JET...HENCE LESS QPF.
GIVEN ANOMALOUS PWATS IN PLACE...DO NOT WANT TO COMPLETELY LET OUR
GUARD DOWN WITH THE POTENTIAL FOR FLOODING...BUT DOES APPEAR
SOMEWHAT LESS OF A RISK THAN YESTERDAY.  NONETHELESS...STILL EXPECT
TYPICAL NUISANCE POOR DRAINAGE STREET FLOODING.

AS FOR TIMING...SOUTHERLY FLOW ALOFT WILL RESULT IN SCATTERED
SHOWERS TUE NIGHT.  BULK OF THE RAIN WILL OCCUR WED INTO EARLY
CHRISTMAS DAY WHEN STRONGEST FORCING COINCIDES HIGH PWAT AIRMASS.
SOME OF THIS RAIN WILL BE HEAVY AT TIMES MAY RESULT IN NUISANCE POOR
DRAINAGE STREET FLOODING.  STILL A LOW RISK FOR MORE SIGNIFICANT
FLOODING GIVEN EXTREMELY HIGH PWATS...BUT SLOWER DEVELOPMENT OF
SECONDARY LOW PRESSURE MAY BE A LIMITING FACTOR.  REGARDLESS...
EXPECT 1 TO 3 INCHES OF RAIN.  WILL CONTINUE TO MENTION A SLIGHT
CHANCE OF THUNDER WITH SHOWALTER INDICES NEAR ZERO.

THE BULK OF THE RAIN SHOULD COME TO AN END CHRISTMAS MORNING WITH
TEMPS PROBABLY AROUND 60 FOR MUCH OF THE REGION.  WHILE GUSTY
SOUTHERLY WINDS ARE EXPECTED WED NIGHT...INVERSION AND WEAKER LOW
LEVEL JET WILL PROBABLY KEEP MOST AREAS BELOW ADVISORY CRITERIA.
STILL HAVE TO WATCH FOR A SMALL WINDOW ON THE COASTAL PLAIN ESP IF
TEMPS CAN EXCEED 60...BUT HIGHER CONFIDENCE IN WIND ON CHRISTMAS
AFTERNOON AND EVENING BEHIND THE SYSTEM.  INCREASING WESTERLY WIND
ALOFT AND STEEPENING LAPSE RATES WILL BRING THE POTENTIAL FOR THESE
WINDS.  DECENT SHOT AT A PERIOD OF 35 TO 50 MPH GUSTS BEHIND THIS
SYSTEM CHRISTMAS AFTERNOON AND EVENING.  WHILE THE GFS IS AN
OUTLIER...IT WOULD EVEN SUGGEST THE POTENTIAL FOR HIGH WIND CRITERIA
TO BE MET WITH 70 KNOTS AT 850 MB.  THAT MAY BE OVERDONE...BUT
SOMETHING WILL HAVE TO KEEP AN EYE ON THE NEXT FEW DAYS.

FRIDAY AND SATURDAY...

UPPER LEVEL RIDGE OFF THE SOUTHEAST COAST WILL KEEP KEEP US IN MILD
SOUTHWEST FLOW ALOFT.  DRY WEATHER EXPECTED WITH FORCING FOR ANY
PRECIPITATION WILL TO OUR NORTHWEST.  HIGHS MAINLY IN THE 40S TO
LOWER 50S.

SUNDAY...

CONFIDENCE IN THE FORECAST GOES DOWN CONSIDERABLE OVER THIS TIME.
DEVELOPING UPPER LEVEL RIDGING INTO ALASKA WILL SEND THE POLAR JET
SOUTHWARD INTO THE CENTRAL U.S.  AT THE SAME TIME...UPPER LEVEL
RIDGE OFF THE SOUTHEAST COAST WILL TRY TO HANG TOUGH.  THE GFS
INSISTS ON DRY AND COLDER WEATHER ARRIVING...BUT WERE NOT CONVINCED.
GIVEN THE SOUTHEAST RIDGE IT MAY HOLD THE COLD AIR UP AND ALLOW
DEVELOPING LOW PRESSURE TO TRACK NEAR NEW ENGLAND SUN AND SUN NIGHT.
THIS COULD BRING RAIN OR SNOW DEPENDING ON ITS TRACK...OBVIOUSLY A
WEEK OUT SO PLENTY OF UNCERTAINTY BUT WOULD LEAN TOWARDS ANOTHER
SYSTEM AND AWAY FROM THE DRY GFS.

&&

.AVIATION /09Z MONDAY THROUGH FRIDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH TUESDAY/...

TODAY...HIGH CONFIDENCE. DRIZZLE OR A FEW FLURRIES POSSIBLE
ACROSS EAST MASS TERMINALS. OTHERWISE ANY VFR CIGS WILL DROP TO
MVFR CONDITIONS THROUGHOUT THE DAY.

TONIGHT...MODERATE CONFIDENCE. MAINLY MVFR CONDITIONS CONTINUE IN
SCATTERED LIGHT SNOW SHOWERS. LIGHT FZRA POSSIBLE LATE MONDAY NIGHT
ACROSS NW MASSACHUSETTS.

TUESDAY...MODERATE CONFIDENCE. MVFR CONDITIONS MAY DROP TO IFR
WITHIN AND HEAVY RAIN FALL. VSBYS WILL BE REDUCED TO 5SM OR LESS
AS WELL.

KBOS TERMINAL...MODERATE CONFIDENCE. COULD SEE DRIZZLE LATER TODAY.

KBDL TERMINAL...MODERATE CONFIDENCE.

OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...

TUESDAY NIGHT INTO THURSDAY MORNING...MODERATE CONFIDENCE.
WIDESPREAD LOW END MVFR TO IFR CONDITIONS EXPECTED IN PERIODS OF
HEAVY SHOWERS/LOW CLOUDS AND FOG PATCHES.  A PERIOD OF SOUTHERLY
WIND GUSTS OF 30 TO 40 KNOTS EXPECTED ON THE COASTAL PLAIN WED
NIGHT.  LLWS ALSO A CONCERN FOR THE ENTIRE REGION WED INTO EARLY THU.

THURSDAY AFTERNOON INTO FRIDAY...MODERATE TO HIGH CONFIDENCE IN
MAINLY VFR.  HOWEVER...A PERIOD OF WESTERLY 30 TO 45 KNOT WIND GUSTS
POSSIBLE THU AFTERNOON AND EVENING.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH TUESDAY/...MODERATE TO HIGH CONFIDENCE.

HIGH PRESSURE ACROSS QUEBEC AND THE MARITIMES WILL RESULT IN
PERSISTENT NORTHEASTERLY TO EASTERLY WINDS ACROSS THE WATERS THROUGH
TODAY. THIS WILL BUILD SEAS TO 5FT ON THE EASTERN WATERS DESPITE
WIND GUSTS UP TO 20 KNOTS. HAVE CONTINUED SCA.

APPROACHING SURFACE LOW PRESSURE FROM THE MID-ATLANTIC TONIGHT WILL
HELP INCREASE AN EASTERLY LLJ OVER THE WATER TOMORROW. THIS WILL
BUILD THE SEAS BETWEEN 5-8 FT. COULD SEE WIND GUSTS BETWEEN 20-30
KTS AS THE FRONT PASSES. SCA HAS BEEN EXPANDED ACCORDINGLY.

OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...MODERATE CONFIDENCE

TUESDAY NIGHT...LONG FETCH EASTERLY FLOW WILL CONTINUE TO RESULT IN
SCA SEAS ACROSS THE OUTER-WATERS WITH HIGH PRESSURE MOVING EAST OF
THE CANADIAN MARITIMES.  WINDS SHOULD GENERALLY BE BELOW SMALL CRAFT
THRESHOLDS.

WEDNESDAY INTO EARLY THURSDAY...INTENSIFYING LOW PRESSURE PASSING
WELL TO OUR WEST WILL CAUSE WINDS TO TURN SOUTHERLY AND BECOME
GUSTY. SMALL CRAFT WIND GUSTS ARE A LOCK.  THE MAIN UNCERTAINTY IS
DO WE SEE SOUTHERLY GALES DEVELOP WED NIGHT.  STRONG LOW LEVEL JET
PRESENT...BUT WE WILL BE DEALING WITH AN INVERSION OVER THE
RELATIVELY COOL OCEAN.  REGARDLESS...STILL SHOULD SEE AT LEAST A
PERIOD OF NEAR GALE FORCE SOUTHERLY WIND GUSTS.

LATER THURSDAY INTO FRIDAY...A PERIOD OF WESTERLY GALE FORCE WIND
GUSTS APPEARS LIKELY IN THE COLD ADVECTION PATTERN BEHIND THE STORM
THU AFTERNOON AND NIGHT.  WINDS SHOULD DIMINISH SOME ON FRIDAY.

&&

.TIDES/COASTAL FLOODING...


HIGH ASTRONOMICAL TIDES OCCUR TUE AND WED.

EAST MASSACHUSETTS COAST:

TUESDAY...HIGH TIDE AT BOSTON WILL BE 11.6 FT AT MIDDAY. WINDS WILL
BE FROM THE EAST AT 10 TO 15 KNOTS...SO THERE WILL BE ONSHORE FLOW
DURING THIS HIGH TIDE.  WHILE THIS IS NOTHING TOO STRONG...GIVEN THE
HIGH ASTRO TIDE EXPECT SOME SPLASH OVER/MINOR COASTAL FLOODING.
CERTAINLY DO NOT EXPECT TO SEE ANY SIGNIFICANT ISSUES.

WEDNESDAY...HIGH TIDE AT BOSTON WILL BE 11.7 FT AT MIDDAY.  WINDS
WILL BE FROM THE SOUTHEAST NEAR 10 KNOTS BUT THERE WILL BE SOME
PRESSURE FALLS WITH INTENSIFYING LOW PRESSURE TO OUR WEST.  THIS
SHOULD BE ENOUGH FOR MORE SPLASH OVER/MINOR COASTAL FLOODING WITH
THE HIGH ASTRO TIDES.  HOWEVER...DO NOT EXPECT ANY SIGNIFICANT
PROBLEMS GIVEN WINDS/SEAS SHOULD BE HELD IN CHECK DURING THE TIME OF
HIGH TIDE.

SOUTH COAST:

WEDNESDAY EVENING...SOUTHERLY WINDS ARE EXPECTED AND ASTRONOMICAL
TIDES INCREASE ALONG THE SOUTH COAST. HIGH TIDE IN PROVIDENCE WILL
BE 5.2 FT THAT EVENING. 925 MB LLJ STRENGTHENS TO 55-65 KTS WHICH
COULD PUSH A 1 TO 2 FOOT SURGE UP ALONG THE SOUTH COAST DURING THE
TIME OF HIGH TIDE.  THE LOW LEVEL INVERSION WILL PROBABLY HOLD THE
STRONGEST WINDS JUST ABOVE THE GROUND...SO THINKING THE RISK IS FOR
SPLASH OVER AND MINOR COASTAL FLOODING.  THERE STILL IS A LOW RISK
FOR MODERATE COASTAL FLOODING...BUT THAT IS OFTEN HARD TO GET IN A
NON-TROPICAL SYSTEM ALONG THE SOUTH COAST.


&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 1 AM TO 7 PM EST TUESDAY FOR ANZ231-
     232-251-256.
     SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 7 PM EST
     TUESDAY FOR ANZ250-254.
     SMALL CRAFT ADVISORY FROM 10 PM THIS EVENING TO 7 PM EST
     TUESDAY FOR ANZ255.

&&

$$
SYNOPSIS...FRANK/DUNTEN
NEAR TERM...DUNTEN
SHORT TERM...DUNTEN
LONG TERM...FRANK
AVIATION...FRANK/DUNTEN
MARINE...FRANK/DUNTEN
TIDES/COASTAL FLOODING...FRANK




000
FXUS61 KBOX 220916
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
416 AM EST MON DEC 22 2014

.SYNOPSIS...

A WAVE OF LOW PRESSURE WILL BRING THE PERIODS OF WET WEATHER MAINLY
LATE TONIGHT INTO TUESDAY NIGHT...WHICH MAY BEGIN AS A BRIEF PERIOD
OF FROZEN PRECIPITATION ACROSS NORTHWEST MASSACHUSETTS.  A MUCH
STRONGER STORM PASSING WELL TO OUR WEST WEDNESDAY INTO CHRISTMAS
MORNING WILL BRING HEAVY RAIN...GUSTY WINDS AND MINOR COASTAL
FLOODING.  DRY WEATHER WITH ABOVE NORMAL TEMPERATURES EXPECTED
CHRISTMAS AFTERNOON INTO SATURDAY.  LOW PRESSURE MAY BRING A RETURN
TO UNSETTLED WEATHER BY WEDNESDAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPPER LEVEL RIDGE BUILDS AHEAD OF DIGGING MIDWEST TROUGH WITH
HIGH PRESSURE REMAINING ANCHORED OVER THE CANADIAN MARITIMES
THROUGH TONIGHT.

EASTERLY FLOW WILL CONTINUE ONSHORE ALLOWING FOR THE PROFILE TO
CONTINUE TO MOISTEN IN THE LOW LEVELS. IF THIS MOISTURE DEEPENS
ENOUGH THEN WE COULD SEE LIGHT SHOWERS DEVELOP ESP ACROSS THE MASS
EAST COASTLINE. OTHERWISE DRIZZLE MAY BE THE MAIN FACTOR AS THE
UPPER LEVELS ARE FAIRLY DRY. OVERALL TODAY WILL BE A COOL AND CLOUDY
DAY WITH HIGHS ONLY REACHING IN THE UPPER 30S TO LOW 40S AS CROSS
SECTIONS ARE VERY MOIST IN THE LOW LEVELS.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
TONIGHT INTO TOMORROW...

*LIGHT FREEZING RAIN IS POSSIBLE ACROSS THE INTERIOR NORTHWEST AND
  NORTHERN WORCESTER HILLS*

A WEAK AREA OF LOW PRESSURE DEVELOPS ALONG A WARM FRONT OFF THE MID
ATLANTIC...DRIFTING NORTHWARD TOWARD THE AREA. THIS LOW REMAINS WEAK
AS THE WARM FRONT MOVES SLOWLY NORTHWARD TONIGHT INTO TOMORROW.
DECENT WARM ADVECTION AHEAD OF THIS WAVE WITH SEVERAL HI-RES
GUIDANCE MODELS SHOWS A POTENTIAL FOR COLD AIR DAMMING ACROSS THE
INTERIOR INTO TUESDAY MORNING.  BIGGEST QUESTION WILL BE THE
MOISTURE POTENTIAL...IS THERE ENOUGH TO DEVELOP PRECIP ESP TONIGHT?
GUIDANCE DOES SHOW ENOUGH LIFT AHEAD OF APPROACHING SURFACE LOW PER
THE GFS/EC SO ANTICIPATE PRECIP TO DEVELOP AND OVERSPREAD ACROSS
SOUTHERN NEW ENGLAND. IF THIS PLAYS OUT WITH COLD AIR DAMMING AND
WARM AIR ADVECTION...THEN WE COULD SEE FREEZING RAIN/DRIZZLE ACROSS
THE INTERIOR NORTHWEST AND NORTHERN WORCESTER HILLS VERY LATE
TONIGHT INTO TUESDAY MORNING. A WINTER WEATHER ADVISORY MAY BE
NEEDED.

AS SURFACE LOW CONTINUES TO MOVE NORTHWARD...AND HIGH PRESSURE OVER
EASTERN CANADA...ANTICIPATE AN INCREASING LLJ. THIS SOUTHEASTERLY
JET WILL CONTINUE TO FEED MOISTURE INTO THE REGION AND WITH
SOUNDINGS SHOW A VERY SATURATED PROFILE COULD SEE NUMEROUS SHOWERS
WITH PERHAPS A FEW HEAVY DOWNPOURS. NOTICED GUIDANCE HAS
INCREASED THE QPF OVER THE PAST FEW DAYS. AS THE WEAK SURFACE LOW
MOVES NORTH OF SOUTHERN NEW ENGLAND...WARM FRONT WILL LIFT
NORTHWARD SO ALL PRECIP BY THE LATE MORNING WILL BE IN THE LIQUID
FORM.

WE COULD ALSO SEE SOME MINOR COASTAL FLOODING CONCERNS ON TUESDAY
WITH DUE EASTERLY FLOW INCREASING TO ABOUT 20 TO 25 MPH.  SEE BELOW
FOR MORE DETAILS.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...

HIGHLIGHTS...

* PERIODS OF RAIN TUE NIGHT INTO XMAS MORNING WILL BE HEAVY AT TIMES
* DRY BY XMAS AFTERNOON BUT WINDY
* TEMPS AROUND 60 FOR SOME LATE WED INTO CHRISTMAS MORNING
* DRY BUT ABOVE NORMAL TEMPS CONTINUE FRI AND SAT
* UNSETTLED WEATHER MAY RETURN BY SUN BUT LOW CONFIDENCE

DETAILS...

TUESDAY NIGHT INTO CHRISTMAS...

STRONG SHORTWAVE WILL DIG ACROSS THE CENTRAL U.S. AND ALLOW DEEP
SOUTH TO SOUTHWEST FLOW ALOFT ACROSS SOUTHERN NEW ENGLAND.  THIS
WILL SEND AND ANOMALOUS MILD AIRMASS INTO SOUTHERN NEW ENGLAND FOR
LATE DECEMBER.  GEFS SHOWING PWATS 4 TO 5 STANDARD DEVIATIONS ABOVE
NORMAL BY WED NIGHT ACROSS OUR REGION.  WHILE HEAVY RAIN IS STILL
EXPECTED...THE MODELS HAVE CUT DOWN ON THE QPF IN THE LAST FEW RUNS.
THE MAIN LOW STILL PASSES WELL TO OUR WEST ACROSS GREAT LAKES...BUT
THEIR SLOWER AND WEAKER WITH SECONDARY DEVELOPMENT ACROSS OUR
REGION.  THIS RESULTS IN A WEAKER LOW LEVEL JET...HENCE LESS QPF.
GIVEN ANOMALOUS PWATS IN PLACE...DO NOT WANT TO COMPLETELY LET OUR
GUARD DOWN WITH THE POTENTIAL FOR FLOODING...BUT DOES APPEAR
SOMEWHAT LESS OF A RISK THAN YESTERDAY.  NONETHELESS...STILL EXPECT
TYPICAL NUISANCE POOR DRAINAGE STREET FLOODING.

AS FOR TIMING...SOUTHERLY FLOW ALOFT WILL RESULT IN SCATTERED
SHOWERS TUE NIGHT.  BULK OF THE RAIN WILL OCCUR WED INTO EARLY
CHRISTMAS DAY WHEN STRONGEST FORCING COINCIDES HIGH PWAT AIRMASS.
SOME OF THIS RAIN WILL BE HEAVY AT TIMES MAY RESULT IN NUISANCE POOR
DRAINAGE STREET FLOODING.  STILL A LOW RISK FOR MORE SIGNIFICANT
FLOODING GIVEN EXTREMELY HIGH PWATS...BUT SLOWER DEVELOPMENT OF
SECONDARY LOW PRESSURE MAY BE A LIMITING FACTOR.  REGARDLESS...
EXPECT 1 TO 3 INCHES OF RAIN.  WILL CONTINUE TO MENTION A SLIGHT
CHANCE OF THUNDER WITH SHOWALTER INDICES NEAR ZERO.

THE BULK OF THE RAIN SHOULD COME TO AN END CHRISTMAS MORNING WITH
TEMPS PROBABLY AROUND 60 FOR MUCH OF THE REGION.  WHILE GUSTY
SOUTHERLY WINDS ARE EXPECTED WED NIGHT...INVERSION AND WEAKER LOW
LEVEL JET WILL PROBABLY KEEP MOST AREAS BELOW ADVISORY CRITERIA.
STILL HAVE TO WATCH FOR A SMALL WINDOW ON THE COASTAL PLAIN ESP IF
TEMPS CAN EXCEED 60...BUT HIGHER CONFIDENCE IN WIND ON CHRISTMAS
AFTERNOON AND EVENING BEHIND THE SYSTEM.  INCREASING WESTERLY WIND
ALOFT AND STEEPENING LAPSE RATES WILL BRING THE POTENTIAL FOR THESE
WINDS.  DECENT SHOT AT A PERIOD OF 35 TO 50 MPH GUSTS BEHIND THIS
SYSTEM CHRISTMAS AFTERNOON AND EVENING.  WHILE THE GFS IS AN
OUTLIER...IT WOULD EVEN SUGGEST THE POTENTIAL FOR HIGH WIND CRITERIA
TO BE MET WITH 70 KNOTS AT 850 MB.  THAT MAY BE OVERDONE...BUT
SOMETHING WILL HAVE TO KEEP AN EYE ON THE NEXT FEW DAYS.

FRIDAY AND SATURDAY...

UPPER LEVEL RIDGE OFF THE SOUTHEAST COAST WILL KEEP KEEP US IN MILD
SOUTHWEST FLOW ALOFT.  DRY WEATHER EXPECTED WITH FORCING FOR ANY
PRECIPITATION WILL TO OUR NORTHWEST.  HIGHS MAINLY IN THE 40S TO
LOWER 50S.

SUNDAY...

CONFIDENCE IN THE FORECAST GOES DOWN CONSIDERABLE OVER THIS TIME.
DEVELOPING UPPER LEVEL RIDGING INTO ALASKA WILL SEND THE POLAR JET
SOUTHWARD INTO THE CENTRAL U.S.  AT THE SAME TIME...UPPER LEVEL
RIDGE OFF THE SOUTHEAST COAST WILL TRY TO HANG TOUGH.  THE GFS
INSISTS ON DRY AND COLDER WEATHER ARRIVING...BUT WERE NOT CONVINCED.
GIVEN THE SOUTHEAST RIDGE IT MAY HOLD THE COLD AIR UP AND ALLOW
DEVELOPING LOW PRESSURE TO TRACK NEAR NEW ENGLAND SUN AND SUN NIGHT.
THIS COULD BRING RAIN OR SNOW DEPENDING ON ITS TRACK...OBVIOUSLY A
WEEK OUT SO PLENTY OF UNCERTAINTY BUT WOULD LEAN TOWARDS ANOTHER
SYSTEM AND AWAY FROM THE DRY GFS.

&&

.AVIATION /09Z MONDAY THROUGH FRIDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH TUESDAY/...

TODAY...HIGH CONFIDENCE. DRIZZLE OR A FEW FLURRIES POSSIBLE
ACROSS EAST MASS TERMINALS. OTHERWISE ANY VFR CIGS WILL DROP TO
MVFR CONDITIONS THROUGHOUT THE DAY.

TONIGHT...MODERATE CONFIDENCE. MAINLY MVFR CONDITIONS CONTINUE IN
SCATTERED LIGHT SNOW SHOWERS. LIGHT FZRA POSSIBLE LATE MONDAY NIGHT
ACROSS NW MASSACHUSETTS.

TUESDAY...MODERATE CONFIDENCE. MVFR CONDITIONS MAY DROP TO IFR
WITHIN AND HEAVY RAIN FALL. VSBYS WILL BE REDUCED TO 5SM OR LESS
AS WELL.

KBOS TERMINAL...MODERATE CONFIDENCE. COULD SEE DRIZZLE LATER TODAY.

KBDL TERMINAL...MODERATE CONFIDENCE.

OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...

TUESDAY NIGHT INTO THURSDAY MORNING...MODERATE CONFIDENCE.
WIDESPREAD LOW END MVFR TO IFR CONDITIONS EXPECTED IN PERIODS OF
HEAVY SHOWERS/LOW CLOUDS AND FOG PATCHES.  A PERIOD OF SOUTHERLY
WIND GUSTS OF 30 TO 40 KNOTS EXPECTED ON THE COASTAL PLAIN WED
NIGHT.  LLWS ALSO A CONCERN FOR THE ENTIRE REGION WED INTO EARLY THU.

THURSDAY AFTERNOON INTO FRIDAY...MODERATE TO HIGH CONFIDENCE IN
MAINLY VFR.  HOWEVER...A PERIOD OF WESTERLY 30 TO 45 KNOT WIND GUSTS
POSSIBLE THU AFTERNOON AND EVENING.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH TUESDAY/...MODERATE TO HIGH CONFIDENCE.

HIGH PRESSURE ACROSS QUEBEC AND THE MARITIMES WILL RESULT IN
PERSISTENT NORTHEASTERLY TO EASTERLY WINDS ACROSS THE WATERS THROUGH
TODAY. THIS WILL BUILD SEAS TO 5FT ON THE EASTERN WATERS DESPITE
WIND GUSTS UP TO 20 KNOTS. HAVE CONTINUED SCA.

APPROACHING SURFACE LOW PRESSURE FROM THE MID-ATLANTIC TONIGHT WILL
HELP INCREASE AN EASTERLY LLJ OVER THE WATER TOMORROW. THIS WILL
BUILD THE SEAS BETWEEN 5-8 FT. COULD SEE WIND GUSTS BETWEEN 20-30
KTS AS THE FRONT PASSES. SCA HAS BEEN EXPANDED ACCORDINGLY.

OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...MODERATE CONFIDENCE

TUESDAY NIGHT...LONG FETCH EASTERLY FLOW WILL CONTINUE TO RESULT IN
SCA SEAS ACROSS THE OUTER-WATERS WITH HIGH PRESSURE MOVING EAST OF
THE CANADIAN MARITIMES.  WINDS SHOULD GENERALLY BE BELOW SMALL CRAFT
THRESHOLDS.

WEDNESDAY INTO EARLY THURSDAY...INTENSIFYING LOW PRESSURE PASSING
WELL TO OUR WEST WILL CAUSE WINDS TO TURN SOUTHERLY AND BECOME
GUSTY. SMALL CRAFT WIND GUSTS ARE A LOCK.  THE MAIN UNCERTAINTY IS
DO WE SEE SOUTHERLY GALES DEVELOP WED NIGHT.  STRONG LOW LEVEL JET
PRESENT...BUT WE WILL BE DEALING WITH AN INVERSION OVER THE
RELATIVELY COOL OCEAN.  REGARDLESS...STILL SHOULD SEE AT LEAST A
PERIOD OF NEAR GALE FORCE SOUTHERLY WIND GUSTS.

LATER THURSDAY INTO FRIDAY...A PERIOD OF WESTERLY GALE FORCE WIND
GUSTS APPEARS LIKELY IN THE COLD ADVECTION PATTERN BEHIND THE STORM
THU AFTERNOON AND NIGHT.  WINDS SHOULD DIMINISH SOME ON FRIDAY.

&&

.TIDES/COASTAL FLOODING...


HIGH ASTRONOMICAL TIDES OCCUR TUE AND WED.

EAST MASSACHUSETTS COAST:

TUESDAY...HIGH TIDE AT BOSTON WILL BE 11.6 FT AT MIDDAY. WINDS WILL
BE FROM THE EAST AT 10 TO 15 KNOTS...SO THERE WILL BE ONSHORE FLOW
DURING THIS HIGH TIDE.  WHILE THIS IS NOTHING TOO STRONG...GIVEN THE
HIGH ASTRO TIDE EXPECT SOME SPLASH OVER/MINOR COASTAL FLOODING.
CERTAINLY DO NOT EXPECT TO SEE ANY SIGNIFICANT ISSUES.

WEDNESDAY...HIGH TIDE AT BOSTON WILL BE 11.7 FT AT MIDDAY.  WINDS
WILL BE FROM THE SOUTHEAST NEAR 10 KNOTS BUT THERE WILL BE SOME
PRESSURE FALLS WITH INTENSIFYING LOW PRESSURE TO OUR WEST.  THIS
SHOULD BE ENOUGH FOR MORE SPLASH OVER/MINOR COASTAL FLOODING WITH
THE HIGH ASTRO TIDES.  HOWEVER...DO NOT EXPECT ANY SIGNIFICANT
PROBLEMS GIVEN WINDS/SEAS SHOULD BE HELD IN CHECK DURING THE TIME OF
HIGH TIDE.

SOUTH COAST:

WEDNESDAY EVENING...SOUTHERLY WINDS ARE EXPECTED AND ASTRONOMICAL
TIDES INCREASE ALONG THE SOUTH COAST. HIGH TIDE IN PROVIDENCE WILL
BE 5.2 FT THAT EVENING. 925 MB LLJ STRENGTHENS TO 55-65 KTS WHICH
COULD PUSH A 1 TO 2 FOOT SURGE UP ALONG THE SOUTH COAST DURING THE
TIME OF HIGH TIDE.  THE LOW LEVEL INVERSION WILL PROBABLY HOLD THE
STRONGEST WINDS JUST ABOVE THE GROUND...SO THINKING THE RISK IS FOR
SPLASH OVER AND MINOR COASTAL FLOODING.  THERE STILL IS A LOW RISK
FOR MODERATE COASTAL FLOODING...BUT THAT IS OFTEN HARD TO GET IN A
NON-TROPICAL SYSTEM ALONG THE SOUTH COAST.


&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 1 AM TO 7 PM EST TUESDAY FOR ANZ231-
     232-251-256.
     SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 7 PM EST
     TUESDAY FOR ANZ250-254.
     SMALL CRAFT ADVISORY FROM 10 PM THIS EVENING TO 7 PM EST
     TUESDAY FOR ANZ255.

&&

$$
SYNOPSIS...FRANK/DUNTEN
NEAR TERM...DUNTEN
SHORT TERM...DUNTEN
LONG TERM...FRANK
AVIATION...FRANK/DUNTEN
MARINE...FRANK/DUNTEN
TIDES/COASTAL FLOODING...FRANK



000
FXUS61 KGYX 220834
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
334 AM EST MON DEC 22 2014

.SYNOPSIS...
AN ONSHORE FLOW MAY PRODUCE SOME FLURRIES OR LIGHT SNOW MAINLY
OVER SOUTHERN REGIONS RIGHT THROUGH TUESDAY. A SIGNIFICANT LOW
PRESSURE SYSTEM WILL GRADUALLY ORGANIZE WEDNESDAY...BEFORE MOVING
OVER THE GREAT LAKES. THIS COULD BRING WINDY CONDITIONS AND THE
POTENTIAL FOR HEAVY RAIN AROUND CHRISTMAS EVE INTO EARLY CHRISTMAS
MORNING. ANOTHER LOW PRESSURE SYSTEM WILL PASS BY TO OUR NORTHWEST
LATE IN THE WEEK AND EARLY NEXT WEEKEND.

&&

.NEAR TERM /THROUGH TODAY/...
AT 07Z...A 1032 MILLIBAR HIGH WAS CENTERED VICINITY OF THE GASPE
PENINSULA. THE HIGH WILL GRADUALLY RETREAT TO THE NORTHEAST
TODAY. COLD ONSHORE FLOW AROUND THIS HIGH WILL PRODUCE SOME
SCATTERED OCEAN EFFECT SNOW SHOWERS OR FLURRIES TODAY MAINLY
ACROSS SOUTHERN AND COASTAL SECTIONS TODAY.

&&

.SHORT TERM /TONIGHT THROUGH 6 PM TUESDAY/...
SCATTERED SNOW SHOWERS AND FLURRIES WILL CONTINUE THROUGH TONIGHT
BECAUSE OF THE PERSISTENT ONSHORE FLOW. COLD AIR DAMMING SHOULD
KEEP THE COLUMN COLD ENOUGH TONIGHT FOR ANY LIGHT PRECIPITATION TO
FALL LARGELY AS SNOW.

BY TUESDAY MORNING...WARM AIR ADVECTION PRECIPITATION AHEAD OF THE
MIDWEST STORM SYSTEM SHOULD BEGIN TO OVERSPREAD THE FORECAST AREA
FROM SOUTH TO NORTH. THERE COULD BE A BRIEF PERIOD OF LIGHT
FREEZING DRIZZLE OR RAIN AS THE WARMER AIR BEGINS TO OVERSPREAD
THE AREA...AS MODELS HINT AT COLD AIR DAMMING ACROSS THE INTERIOR.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
EXTENDED PERIOD WX TO BE DRIVEN BY SERIES OF DOWNSTREAM BLOCKS OVER
THE ATLANTIC AND EUROPE...WHICH WILL HELP BUILD RIDGING AND HIGHER
AMPLITUDE THROUGH THE WEEK AND INTO EARLY NEXT WEEKEND...BEFORE
THERE ARE SIGNS OF THE BLOCKING BREAKING DOWN AND ALLOWING COLDER
AIR TO MOVE IN.

WE START THE PERIOD DURING THE CHRISTMAS HOLIDAY PERIOD AND THE
PREVIOUSLY ADVERTISED STORM SYSTEM THAT WILL THE CWA WED INTO THU.
MOST OF THE SHORT TO MEDIUM RANGE MODELS HAVE INTRODUCED AN
IMPORTANT CHANGE TO THE FORECAST...AND THAT ALLOWS THE FIRST NRN
STREAM 500MB WAVE TO PASS BY WITH OUT MUCH INTERACTION WITH THE
LARGER SCALE TROUGH...WHICH LINGERS OVER THE GULF STATES UNTIL
EARLY WED MORNING. THIS WOULD MAKE FOR A LESS IMPRESSIVE SFC LOW
THAT INTENSIFIES LATER AND FURTHER N...WHICH WOULD LIMIT THE
DEVELOPMENT OF THE LOW LVL JET...AND THEREFORE BRING DOWN
QPF...AND ALSO LOWER THE HTREAT FRO STRONG WINDS. THIS SCENARIO IS
SUPPORTED BY THE 00Z EURO AND GFS...AND TO SOME DEGREE THE
NAM...ALTHOUGH THAT REALLY HOLDS BACK THE 500 MB CLOSED LOW. THE
00Z CMC HEMI IS THE ONE MODEL THAT TEND TOWARD BETTER PHASING AND
HOLDS ONTO A STRONGER SINGLE SFC LOW. THESE CHANGES IN THE MODELS
MAY BE THE RESULT ONE OR ALL OF THE WAVES INVOLVED IN GETTING THIS
STORM TOGETHER HAVE MOVES INTO A MORE WELL SAMPLED PART OF THE
MODEL DOMAIN. THERES ALSO STILL THE ISSUE OF DEEP CONVECTION IN
THE FORECAST TUE AFFECTING THE MODELS AS WELL. GIVEN ALL THAT WILL
BE STICKING CLOSER TO THE GFS/EURO...AND BLENDING BACK IN SOME OF
THE PREVIOUS FORECAST...PARTIALLY FOR THE SAKE OF CONTINUITY.

OVERALL...THE SAME ISSUES PREVAIL FROM PREVIOUS
FORECASTS...ALTHOUGH TO A LESSER DEGREE...AND IT WILL PRETTY MUCH
BE PRECIPITATING /MOSTLY RAIN/ FROM TUESDAY RIGHT INTO CHRISTMAS
MORNING. THE FIRST CHANGE IN THE FORECAST WILL BE THAT THE COLDER
AIR WILL HANG ON LONGER...INTO WED MORNING. IN MOST PLACES TEMPS
WILL BE ABV FREEZING THRU TUE NIGHT...BUT WE COULD SEE A PERIOD
OF FZRA IN THE MTNS...WITH A TENTH OR TWO OF ICE ACCUMS BEFORE
TEMPS RISE ABV THERE BY MIDDAY. S WINDS WILL PICK UP...BUT NOT
UNTIL LATER IN THE DAY WED...AND WILL LKLY NOT BE AS GUSTY WED
NIGHT...BUT COULD GUST TO 30 MPH OR IN THE W FLOW BEHIND THE LOW
ON THU. QPF WAS LOWERED TOO...BUT STILL WILL SEE A PERIOD OF HEAVY
RAIN...BUT THAT WILL PROBABLY BE LIMITED TO WED NIGHT. QPF AROUND
2 INCHES ACROSS THE CWA...LOWEST N OF THE MTNS AND HIGHEST IN THE
UPSLOPE AREAS. ALSO...THE WARMER AIR WILL NOT COME IN AS QUICKLY
AND THIS WILL HELP LIMIT SNOW MELT AND THUS MITIGATING THE
FLOODING THREAT SOME. STILL...WILL SEE ENOUGH RAIN THAT SOME
FLOODING PROBLEMS ARE POSSIBLE. FINALLY TEMPS WILL PUSH UP INTO
THE 50S IN THE SRN ZONES...WITH THE WARMEST READINGS LKLY WED
NIGHT INTO THU MORNING.

ALTHOUGH IT COOLS DOWN SOMEWHAT BEHIND THEIS SYSTEM...TEMPS WILL
REMAIN ABV NORMAL...BY 5-10F FRI AND SAT AS HIGH PRES BUILDS IN.
NEXT CHC FOR ANY SIGNIF PRECIP WILL BE LATE IN THE WEEKEND.

&&

.AVIATION /08Z MONDAY THROUGH FRIDAY/...
SHORT TERM...MAINLY VFR THROUGH TONIGHT...HOWEVER THERE MAY BE
BRIEFLY MVFR CONDITIONS IN SCATTERED SNOW SHOWERS SOUTHERN
LOCATIONS. MVFR CONDS EXPECTED FOR TUE.

LONG TERM...EXTENDED PERIOD OF FLIGHT RESTRICTIONS TUS NIGHT INTO
THU MORNING. LOOK FOR IFR OR LOWER TUE NIGHT...WITH SOME
IMPROVEMENT TO MVFR DURING THE DAY WED...AND A RETURN TO IFR WED
NIGHT. EXPECT IMPROVEMENT TO VFR THU AFTERNOON...WHICH SHOULD
HOLD THRU FRIDAY.

&&

.MARINE...
SHORT TERM...WINDS AND SEAS WILL REMAIN BELOW SCA CONDITIONS
THROUGH LATE TONIGHT. AN SCA WILL LIKELY BE NEEDED BY TUESDAY IN
INCREASING WINDS AND SEAS.

LONG TERM...MODELS CONTINUE TO BACK OFF THE STRONG WINDS WED INTO
THU...BUT STILL EXPECT A PERIOD OF GALES...POSSIBLE IN THE S FLOW
LATE WED AND WED NIGHT...BUT MORE LKLY IN STRONG W FLOW THU INTO
THU NIGHT.

&&

.HYDROLOGY...
MODELS CONTINUE TO BACK OFF ON RAINFALL TOTALS FOR
THE CHRISTMAS EVE/EARLY CHRISTMAS MORNING EVENT...BUT AREA STILL
AROUND 2 INCHES. HOPING THE SNOWPACK IN THE MOUNTAINS AND
FOOTHILLS WILL TAKE IN SOME OF THE RAINFALL IN THAT AREA...BUT
STILL EXPECT SOME RAPID RISES IN THE HEADWATERS. IN ANY
CASE...WHILE THE THREAT OF FLOODING IS LOWER...IT STILL REMAINS A
POSSIBILITY WED NIGHT INTO THU.

&&

.TIDES/COASTAL FLOODING...
ASTRONOMICAL TIDES ARE AT THEIR PEAK FOR THE MONTH. THIS...IN
COMBINATION WITH STRONG SOUTHERLY GALES WILL LIKELY ALLOW FOR
SOME STORM SURGE. WAVES PROB NOT QUITE AS HIGH AS PREV
FORECASTS...MAYBE 10 TO 12 FT...BUT THERE IS SOME POTENTIAL FOR
MINOR COASTAL FLOODING...WITH SPLASH OVER AND BEACH EROSION
DISTINCT POSSIBILITY.


&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.

&&

$$
SCHWIBS/CEMPA



000
FXUS61 KGYX 220834
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
334 AM EST MON DEC 22 2014

.SYNOPSIS...
AN ONSHORE FLOW MAY PRODUCE SOME FLURRIES OR LIGHT SNOW MAINLY
OVER SOUTHERN REGIONS RIGHT THROUGH TUESDAY. A SIGNIFICANT LOW
PRESSURE SYSTEM WILL GRADUALLY ORGANIZE WEDNESDAY...BEFORE MOVING
OVER THE GREAT LAKES. THIS COULD BRING WINDY CONDITIONS AND THE
POTENTIAL FOR HEAVY RAIN AROUND CHRISTMAS EVE INTO EARLY CHRISTMAS
MORNING. ANOTHER LOW PRESSURE SYSTEM WILL PASS BY TO OUR NORTHWEST
LATE IN THE WEEK AND EARLY NEXT WEEKEND.

&&

.NEAR TERM /THROUGH TODAY/...
AT 07Z...A 1032 MILLIBAR HIGH WAS CENTERED VICINITY OF THE GASPE
PENINSULA. THE HIGH WILL GRADUALLY RETREAT TO THE NORTHEAST
TODAY. COLD ONSHORE FLOW AROUND THIS HIGH WILL PRODUCE SOME
SCATTERED OCEAN EFFECT SNOW SHOWERS OR FLURRIES TODAY MAINLY
ACROSS SOUTHERN AND COASTAL SECTIONS TODAY.

&&

.SHORT TERM /TONIGHT THROUGH 6 PM TUESDAY/...
SCATTERED SNOW SHOWERS AND FLURRIES WILL CONTINUE THROUGH TONIGHT
BECAUSE OF THE PERSISTENT ONSHORE FLOW. COLD AIR DAMMING SHOULD
KEEP THE COLUMN COLD ENOUGH TONIGHT FOR ANY LIGHT PRECIPITATION TO
FALL LARGELY AS SNOW.

BY TUESDAY MORNING...WARM AIR ADVECTION PRECIPITATION AHEAD OF THE
MIDWEST STORM SYSTEM SHOULD BEGIN TO OVERSPREAD THE FORECAST AREA
FROM SOUTH TO NORTH. THERE COULD BE A BRIEF PERIOD OF LIGHT
FREEZING DRIZZLE OR RAIN AS THE WARMER AIR BEGINS TO OVERSPREAD
THE AREA...AS MODELS HINT AT COLD AIR DAMMING ACROSS THE INTERIOR.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
EXTENDED PERIOD WX TO BE DRIVEN BY SERIES OF DOWNSTREAM BLOCKS OVER
THE ATLANTIC AND EUROPE...WHICH WILL HELP BUILD RIDGING AND HIGHER
AMPLITUDE THROUGH THE WEEK AND INTO EARLY NEXT WEEKEND...BEFORE
THERE ARE SIGNS OF THE BLOCKING BREAKING DOWN AND ALLOWING COLDER
AIR TO MOVE IN.

WE START THE PERIOD DURING THE CHRISTMAS HOLIDAY PERIOD AND THE
PREVIOUSLY ADVERTISED STORM SYSTEM THAT WILL THE CWA WED INTO THU.
MOST OF THE SHORT TO MEDIUM RANGE MODELS HAVE INTRODUCED AN
IMPORTANT CHANGE TO THE FORECAST...AND THAT ALLOWS THE FIRST NRN
STREAM 500MB WAVE TO PASS BY WITH OUT MUCH INTERACTION WITH THE
LARGER SCALE TROUGH...WHICH LINGERS OVER THE GULF STATES UNTIL
EARLY WED MORNING. THIS WOULD MAKE FOR A LESS IMPRESSIVE SFC LOW
THAT INTENSIFIES LATER AND FURTHER N...WHICH WOULD LIMIT THE
DEVELOPMENT OF THE LOW LVL JET...AND THEREFORE BRING DOWN
QPF...AND ALSO LOWER THE HTREAT FRO STRONG WINDS. THIS SCENARIO IS
SUPPORTED BY THE 00Z EURO AND GFS...AND TO SOME DEGREE THE
NAM...ALTHOUGH THAT REALLY HOLDS BACK THE 500 MB CLOSED LOW. THE
00Z CMC HEMI IS THE ONE MODEL THAT TEND TOWARD BETTER PHASING AND
HOLDS ONTO A STRONGER SINGLE SFC LOW. THESE CHANGES IN THE MODELS
MAY BE THE RESULT ONE OR ALL OF THE WAVES INVOLVED IN GETTING THIS
STORM TOGETHER HAVE MOVES INTO A MORE WELL SAMPLED PART OF THE
MODEL DOMAIN. THERES ALSO STILL THE ISSUE OF DEEP CONVECTION IN
THE FORECAST TUE AFFECTING THE MODELS AS WELL. GIVEN ALL THAT WILL
BE STICKING CLOSER TO THE GFS/EURO...AND BLENDING BACK IN SOME OF
THE PREVIOUS FORECAST...PARTIALLY FOR THE SAKE OF CONTINUITY.

OVERALL...THE SAME ISSUES PREVAIL FROM PREVIOUS
FORECASTS...ALTHOUGH TO A LESSER DEGREE...AND IT WILL PRETTY MUCH
BE PRECIPITATING /MOSTLY RAIN/ FROM TUESDAY RIGHT INTO CHRISTMAS
MORNING. THE FIRST CHANGE IN THE FORECAST WILL BE THAT THE COLDER
AIR WILL HANG ON LONGER...INTO WED MORNING. IN MOST PLACES TEMPS
WILL BE ABV FREEZING THRU TUE NIGHT...BUT WE COULD SEE A PERIOD
OF FZRA IN THE MTNS...WITH A TENTH OR TWO OF ICE ACCUMS BEFORE
TEMPS RISE ABV THERE BY MIDDAY. S WINDS WILL PICK UP...BUT NOT
UNTIL LATER IN THE DAY WED...AND WILL LKLY NOT BE AS GUSTY WED
NIGHT...BUT COULD GUST TO 30 MPH OR IN THE W FLOW BEHIND THE LOW
ON THU. QPF WAS LOWERED TOO...BUT STILL WILL SEE A PERIOD OF HEAVY
RAIN...BUT THAT WILL PROBABLY BE LIMITED TO WED NIGHT. QPF AROUND
2 INCHES ACROSS THE CWA...LOWEST N OF THE MTNS AND HIGHEST IN THE
UPSLOPE AREAS. ALSO...THE WARMER AIR WILL NOT COME IN AS QUICKLY
AND THIS WILL HELP LIMIT SNOW MELT AND THUS MITIGATING THE
FLOODING THREAT SOME. STILL...WILL SEE ENOUGH RAIN THAT SOME
FLOODING PROBLEMS ARE POSSIBLE. FINALLY TEMPS WILL PUSH UP INTO
THE 50S IN THE SRN ZONES...WITH THE WARMEST READINGS LKLY WED
NIGHT INTO THU MORNING.

ALTHOUGH IT COOLS DOWN SOMEWHAT BEHIND THEIS SYSTEM...TEMPS WILL
REMAIN ABV NORMAL...BY 5-10F FRI AND SAT AS HIGH PRES BUILDS IN.
NEXT CHC FOR ANY SIGNIF PRECIP WILL BE LATE IN THE WEEKEND.

&&

.AVIATION /08Z MONDAY THROUGH FRIDAY/...
SHORT TERM...MAINLY VFR THROUGH TONIGHT...HOWEVER THERE MAY BE
BRIEFLY MVFR CONDITIONS IN SCATTERED SNOW SHOWERS SOUTHERN
LOCATIONS. MVFR CONDS EXPECTED FOR TUE.

LONG TERM...EXTENDED PERIOD OF FLIGHT RESTRICTIONS TUS NIGHT INTO
THU MORNING. LOOK FOR IFR OR LOWER TUE NIGHT...WITH SOME
IMPROVEMENT TO MVFR DURING THE DAY WED...AND A RETURN TO IFR WED
NIGHT. EXPECT IMPROVEMENT TO VFR THU AFTERNOON...WHICH SHOULD
HOLD THRU FRIDAY.

&&

.MARINE...
SHORT TERM...WINDS AND SEAS WILL REMAIN BELOW SCA CONDITIONS
THROUGH LATE TONIGHT. AN SCA WILL LIKELY BE NEEDED BY TUESDAY IN
INCREASING WINDS AND SEAS.

LONG TERM...MODELS CONTINUE TO BACK OFF THE STRONG WINDS WED INTO
THU...BUT STILL EXPECT A PERIOD OF GALES...POSSIBLE IN THE S FLOW
LATE WED AND WED NIGHT...BUT MORE LKLY IN STRONG W FLOW THU INTO
THU NIGHT.

&&

.HYDROLOGY...
MODELS CONTINUE TO BACK OFF ON RAINFALL TOTALS FOR
THE CHRISTMAS EVE/EARLY CHRISTMAS MORNING EVENT...BUT AREA STILL
AROUND 2 INCHES. HOPING THE SNOWPACK IN THE MOUNTAINS AND
FOOTHILLS WILL TAKE IN SOME OF THE RAINFALL IN THAT AREA...BUT
STILL EXPECT SOME RAPID RISES IN THE HEADWATERS. IN ANY
CASE...WHILE THE THREAT OF FLOODING IS LOWER...IT STILL REMAINS A
POSSIBILITY WED NIGHT INTO THU.

&&

.TIDES/COASTAL FLOODING...
ASTRONOMICAL TIDES ARE AT THEIR PEAK FOR THE MONTH. THIS...IN
COMBINATION WITH STRONG SOUTHERLY GALES WILL LIKELY ALLOW FOR
SOME STORM SURGE. WAVES PROB NOT QUITE AS HIGH AS PREV
FORECASTS...MAYBE 10 TO 12 FT...BUT THERE IS SOME POTENTIAL FOR
MINOR COASTAL FLOODING...WITH SPLASH OVER AND BEACH EROSION
DISTINCT POSSIBILITY.


&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.

&&

$$
SCHWIBS/CEMPA




000
FXUS61 KBOX 220743
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
243 AM EST MON DEC 22 2014

.SYNOPSIS...
SCATTERED SNOW/RAIN SHOWERS WILL CONTINUE TODAY THANKS TO THE
ONSHORE FLOW. A WEAK LOW PRESSURE WILL MOVE ACROSS NEW ENGLAND
BRINGING A PERIOD OF PRECIPITATION VERY LATE MONDAY NIGHT AND
INTO TUESDAY. A MUCH STRONGER STORM PASSING WEST OF NEW ENGLAND
WILL BRING HEAVY RAINFALL...GUSTY WINDS AND COASTAL FLOODING
CONCERNS TO THE REGION WEDNESDAY AND WEDNESDAY NIGHT. DRY BUT VERY
WINDY CONDITIONS FOLLOW FOR CHRISTMAS DAY. HIGH PRESSURE BRINGS
DRY WEATHER FRIDAY. ANOTHER DEVELOPING SYSTEM MAY BRING RAIN AND
SNOW NEXT SUNDAY.

&&

.NEAR TERM /THROUGH TODAY/...

UPPER LEVEL RIDGE BUILDS AHEAD OF DIGGING MIDWEST TROUGH WITH
HIGH PRESSURE REMAINING ANCHORED OVER THE CANADIAN MARITIMES
THROUGH TONIGHT.

EASTERLY FLOW WILL CONTINUE ONSHORE ALLOWING FOR THE PROFILE TO
CONTINUE TO MOISTEN IN THE LOW LEVELS. IF THIS MOISTURE DEEPENS
ENOUGH THEN WE COULD SEE LIGHT SHOWERS DEVELOP ESP ACROSS THE MASS
EAST COASTLINE. OTHERWISE DRIZZLE MAY BE THE MAIN FACTOR AS THE
UPPER LEVELS ARE FAIRLY DRY. OVERALL TODAY WILL BE A COOL AND CLOUDY
DAY WITH HIGHS ONLY REACHING IN THE UPPER 30S TO LOW 40S AS CROSS
SECTIONS ARE VERY MOIST IN THE LOW LEVELS.

&&

.SHORT TERM /TONIGHT THROUGH 6 PM TUESDAY/...

TONIGHT INTO TOMORROW...

*LIGHT FREEZING RAIN IS POSSIBLE ACROSS THE INTERIOR NORTHWEST AND
  NORTHERN WORCESTER HILLS*

A WEAK AREA OF LOW PRESSURE DEVELOPS ALONG A WARM FRONT OFF THE MID
ATLANTIC...DRIFTING NORTHWARD TOWARD THE AREA. THIS LOW REMAINS WEAK
AS THE WARM FRONT MOVES SLOWLY NORTHWARD TONIGHT INTO TOMORROW.
DECENT WARM ADVECTION AHEAD OF THIS WAVE WITH SEVERAL HI-RES
GUIDANCE MODELS SHOWS A POTENTIAL FOR COLD AIR DAMMING ACROSS THE
INTERIOR INTO TUESDAY MORNING.  BIGGEST QUESTION WILL BE THE
MOISTURE POTENTIAL...IS THERE ENOUGH TO DEVELOP PRECIP ESP TONIGHT?
GUIDANCE DOES SHOW ENOUGH LIFT AHEAD OF APPROACHING SURFACE LOW PER
THE GFS/EC SO ANTICIPATE PRECIP TO DEVELOP AND OVERSPREAD ACROSS
SOUTHERN NEW ENGLAND. IF THIS PLAYS OUT WITH COLD AIR DAMMING AND
WARM AIR ADVECTION...THEN WE COULD SEE FREEZING RAIN/DRIZZLE ACROSS
THE INTERIOR NORTHWEST AND NORTHERN WORCESTER HILLS VERY LATE
TONIGHT INTO TUESDAY MORNING. A WINTER WEATHER ADVISORY MAY BE
NEEDED.

AS SURFACE LOW CONTINUES TO MOVE NORTHWARD...AND HIGH PRESSURE OVER
EASTERN CANADA...ANTICIPATE AN INCREASING LLJ. THIS SOUTHEASTERLY
JET WILL CONTINUE TO FEED MOISTURE INTO THE REGION AND WITH
SOUNDINGS SHOW A VERY SATURATED PROFILE COULD SEE NUMEROUS SHOWERS
WITH PERHAPS A FEW HEAVY DOWNPOURS. NOTICED GUIDANCE HAS
INCREASED THE QPF OVER THE PAST FEW DAYS. AS THE WEAK SURFACE LOW
MOVES NORTH OF SOUTHERN NEW ENGLAND...WARM FRONT WILL LIFT
NORTHWARD SO ALL PRECIP BY THE LATE MORNING WILL BE IN THE LIQUID
FORM.

WE COULD ALSO SEE SOME MINOR COASTAL FLOODING CONCERNS ON TUESDAY
WITH DUE EASTERLY FLOW INCREASING TO ABOUT 20 TO 25 MPH.  SEE BELOW
FOR MORE DETAILS.


&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
BIG PICTURE...

TUESDAY STARTS WITH UPPER RIDGES ON EACH COAST AND A DEEP UPPER
TROUGH/CLOSED LOW OVER THE PLAINS. BY WEDNESDAY THE CLOSED LOW
EJECTS NORTHEAST THROUGH LAKE SUPERIOR INTO CANADA. THIS SWEEPS THE
TROUGH AXIS EAST AND PASSES ACROSS NEW ENGLAND CHRISTMAS DAY.
ANOTHER SHORTWAVE MOVES ONSHORE IN THE PACIFIC NORTHWEST WEDNESDAY
AND PHASES WITH A SECOND DROPPING SOUTH FROM NORTHERN CANADA.  THIS
REESTABLISHES THE UPPER TROUGH OVER THE NORTHERN PLAINS/GREAT LAKES
SATURDAY.

CONTOUR HEIGHTS WILL BE ABOVE NORMAL MIDWEEK...TRENDING BELOW NORMAL
OVER THE WEEKEND AS THE SECOND UPPER TROUGH SHIFTS EAST. THIS POINTS
TO A COOLING TREND AFTER CHRISTMAS.

THE GFS AND ECMWF ARE SIMILAR IN HANDLING THE HOLIDAY STORM. THERE
ARE DIFFERENCES BETWEEN THE MODELS IN HANDLING THE SUNDAY SYSTEM. WE
USED A BLEND MOST OF THE LONG TERM PERIOD...BUT MANUALLY ADJUSTED
POPS FOR SUNDAY WITH LOW CONFIDENCE IN MODEL VALUES.

THE DAILIES...

TUESDAY... HIGH PRESSURE OVER THE MARITIMES WITH RIDGING DOWN THE
ATLANTIC COAST. COASTAL LOW PRESSURE WAVE DEVELOPS ALONG STALLED
WARM FRONT AND MOVES NORTH.  AS THE COASTAL LOW MOVES NORTH IT WILL
RUN UP AGAINST THE MARITIME HIGH. THIS WILL INCREASE THE LOW LEVEL
PRESSURE GRADIENT AND INCREASE THE LOW LEVEL SOUTHEAST WINDS.
RESULT...A SOUTHEAST LOW LEVEL JET RUNS OVER THE RIDGING ALONG THE
COASTAL PLAIN INDUCING LOW LEVEL LIFT. THE MOIST LAYER EXPANDS ABOVE
800 MB...NOT DEEP BUT DEEP ENOUGH FOR THE LIFT TO GENERATE LIGHT
PCPN. PTYPE WILL BE RAIN MOST PLACES...BUT THERE COULD BE SPOTS OF
LIGHT FREEZING RAIN IN NORTHWEST MASSACHUSETTS. WE WILL MAINTAIN
CHANCE POPS BUT INCREASE TO AROUND 50 PCT...THE HIGH END OF THE
CHANCE RANGE.

LOW LEVEL SOUTH JET MOVES UP THE COAST TUESDAY NIGHT REACHING THE
COOLER AIR OVER NEW ENGLAND AFTER MIDNIGHT AND BEFORE SUNRISE. THIS
WILL GENERATE ADDITIONAL LIFT AS WELL AS INCREASING AND DEEPENING
MOISTURE. THIS SUGGESTS INCREASING POPS OVERNIGHT.  TEMPERATURES
SHOULD REMAIN ABOVE FREEZING SO PTYPE SHOULD BE RAIN.

WEDNESDAY-THURSDAY... SOUTH 40-50 KNOT LOW LEVEL JET MOVES OVER NEW
ENGLAND WEDNESDAY GENERATING STRONG LIFT AND TRANSPORTING HIGH
VALUES OF PRECIPITABLE WATER INTO THAT LIFT. THE MOISTURE VALUES ARE
MORE THAN 3 STD DEVIATIONS ABOVE NORMAL FOR DECEMBER...AND ACTUALLY
NEAR THE MAXIMUM PREVIOUSLY OBSERVED VALUE. THIS SUGGESTS RAIN WITH
SOME HEAVY DOWNPOURS. COLD FRONT APPROACHES LATE WEDNESDAY NIGHT AND
CROSSES SOUTHERN NEW ENGLAND CHRISTMAS MORNING. THE FRONT WILL HAVE
DYNAMIC SUPPORT FROM A 140-150 KNOT UPPER JET. THE FOREWARD PROGRESS
OF THE FRONT WILL SLOW BECAUSE MOST OF THE MOTION IN THE UPPER JET
WILL BE PARALLEL TO THE FRONT. THIS WILL MEAN CONTINUED RAIN/HEAVY
RAIN THROUGH THE NIGHT INTO THURSDAY MORNING.

THE OBVIOUS CONCERN FOR THIS PERIOD WILL BE FLOODING FROM HEAVY
RAINFALL. RAIN AMOUNTS OF 2 TO 3 INCHES ARE EXPECTED. THIS SHOULD BE
SUFFICIENT FOR AT LEAST URBAN AND POOR DRAINAGE FLOODING. A FLOOD
WATCH MAY BE NEEDED.

A SECOND CONCERN WILL BE WIND. THE LOW LEVEL JET WEDNESDAY WILL BE
SOUTH 40-50 KNOTS...AND INCREASE TO 55-65 KNOTS WEDNESDAY NIGHT.
CONVENTIONAL MIXING WILL NOT BE DEEP...BUT HEAVY DOWNPOURS COULD
CREATE A MOIST ADIABATIC CHANNEL THAT BRINGS DOWN SOME STRONGER WIND
GUSTS. MODEL GRIDS ARE RATHER LIGHT ON WIND GUSTS...15 TO 30 KNOTS.
WE WILL MANUALLY ADJUST THESE VALUES UP TO 25-35 KNOTS OVER LAND AND
A LITTLE STRONGER OVER WATER.

A THIRD CONCERN WILL BE COASTAL FLOODING. MORE DETAILS ON THIS IN
THE TIDE/COASTAL FLOOD SECTION.

WINDS SHIFT TO WEST BEHIND THE FRONT ON CHRISTMAS DAY. THIS WILL
BRING DRIER AIR AND SO END THE RAINFALL. COLD ADVECTION WILL PROMOTE
MIXING TO NEAR 850 MB IN THE AFTERNOON AND TAP 25-35 KNOT WIND
GUSTS...POSSIBLY 40 KNOT GUSTS. A WIND ADVISORY MAY BE NEEDED FOR
THESE WEST WINDS THURSDAY.

FRIDAY THROUGH SUNDAY.... HIGH PRESSURE MOVES OVER THE REGION FRIDAY
BRINGING DRY WEATHER.  SHORTWAVE MOVING THROUGH THE GREAT LAKES
SWINGS A COLD FRONT THROUGH NEW ENGLAND SATURDAY. THE SURFACE
REFLECTION OF THE SHORTWAVE MOVES UP THE ST LAWRENCE VALLEY AND JET
SUPPORT WILL MOSTLY BE NORTH OF THE BORDER...SO PCPN WILL BE
LIMITED. QUESTION FOR SUNDAY WILL BE WHETHER A WAVE FORMS ON THE
DEPARTING COLD FRONT...IF SO IT MIGHT BRING PCPN TO NEW ENGLAND.
THE ECMWF THINKS SO BUT THE GFS DOES NOT. WE BROUGHT IN A CHANCE
OF RAIN AND SNOW SHOWERS.

&&

.AVIATION /08Z MONDAY THROUGH FRIDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH TUESDAY/...

TODAY...HIGH CONFIDENCE. DRIZZLE OR A FEW FLURRIES POSSIBLE
ACROSS EAST MASS TERMINALS. OTHERWISE ANY VFR CIGS WILL DROP TO
MVFR CONDITIONS THROUGHOUT THE DAY.

TONIGHT...MODERATE CONFIDENCE. MAINLY MVFR CONDITIONS CONTINUE IN
SCATTERED LIGHT SNOW SHOWERS. LIGHT FZRA POSSIBLE LATE MONDAY NIGHT
ACROSS NW MASSACHUSETTS.

TUESDAY...MODERATE CONFIDENCE. MVFR CONDITIONS MAY DROP TO IFR
WITHIN AND HEAVY RAIN FALL. VSBYS WILL BE REDUCED TO 5SM OR LESS
AS WELL.

KBOS TERMINAL...MODERATE CONFIDENCE. COULD SEE DRIZZLE LATER TODAY.

KBDL TERMINAL...MODERATE CONFIDENCE.

OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...MODERATE CONFIDENCE

LATE TUESDAY NIGHT-WEDNESDAY-THURSDAY... CONDITIONS LOWERING TO
IFR/LIFR IN RAIN/HEAVY RAIN. SOUTHEAST WINDS GUSTING 25 TO 35
KNOTS WEDNESDAY AND SOUTH WINDS SIMILAR SPEEDS WEDNESDAY
NIGHT...EXCEPT 30 TO 40 KNOTS CAPE COD AND ISLANDS. WINDS AT 2000
FEET MAY REACH 55 TO 65 KNOTS BY WEDNESDAY NIGHT CREATING LOW
LEVEL WIND SHEAR. ISOLATED THUNDERSTORMS WEDNESDAY AFTERNOON AND
NIGHT. COLD FRONT SWINGS THROUGH ON THURSDAY MORNING BRINGING A
WIND SHIFT TO WEST WITH GUSTS 30-40 KNOTS. CONDITIONS IMPROVE TO
VFR AFTER THE WIND SHIFT.

FRIDAY...VFR.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH TUESDAY/...MODERATE TO HIGH CONFIDENCE.

HIGH PRESSURE ACROSS QUEBEC AND THE MARITIMES WILL RESULT IN
PERSISTENT NORTHEASTERLY TO EASTERLY WINDS ACROSS THE WATERS THROUGH
TODAY. THIS WILL BUILD SEAS TO 5FT ON THE EASTERN WATERS DESPITE
WIND GUSTS UP TO 20 KNOTS. HAVE CONTINUED SCA.

APPROACHING SURFACE LOW PRESSURE FROM THE MID-ATLANTIC TONIGHT WILL
HELP INCREASE AN EASTERLY LLJ OVER THE WATER TOMORROW. THIS WILL
BUILD THE SEAS BETWEEN 5-8 FT. COULD SEE WIND GUSTS BETWEEN 20-30
KTS AS THE FRONT PASSES. SCA HAS BEEN EXPANDED ACCORDINGLY.

OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...MODERATE CONFIDENCE

WEDNESDAY-THURSDAY... SOUTH WINDS WITH FREQUENT GUSTS 35 TO 40
KNOTS BY WEDNESDAY AFTERNOON AND CONTINUING THROUGH THE NIGHT.
WINDS SHIFT WEST THURSDAY MORNING WITH SIMILAR SPEEDS THROUGH THE
AFTERNOON. SEAS WILL BUILD TO 7 TO 12 FEET ON THE EXPOSED WATERS
BY WEDNESDAY NIGHT AND THURSDAY. A GALE WARNING MAY BE NEEDED.

FRIDAY...WINDS DIMINISHING TO 25 KNOTS FRIDAY MORNING AND BELOW 25
KNOTS BY AFTERNOON.  SEAS LINGERING AT 5 TO 7 FEET ON THE EXPOSED
WATERS. A SMALL CRAFT ADVISORY MAY BE NEEDED.

&&

.TIDES/COASTAL FLOODING...
HIGH ASTRONOMICAL TIDES WILL OCCUR TUESDAY THROUGH THURSDAY.

TUESDAY...HIGH TIDE AT BOSTON WILL BE 11.6 FT. WINDS WILL BE FROM
THE EAST...SO THERE WILL BE ONSHORE FLOW DURING THIS HIGH TIDE
ALLOWING FOR MINOR SPLASHOVER. IF WINDS INCREASE THEN COULD SEE
SOME POCKETS OF MINOR COASTAL FLOODING.

WEDNESDAY...WINDS SHIFT TO A MORE SOUTHEASTERLY FLOW DURING THE DAY
AND INCREASE QUICKLY AS AN APPROACHING SYSTEM BRINGS PRESSURE
FALLS OF 1 MB/HR. THE WEDNESDAY AFTERNOON HIGH TIDE IN BOSTON IS
11.7 FT AND STRONG SOUTHEASTERLY WINDS WILL BE JUST OFFSHORE.
RIGHT NOW BELIEVE MINOR COASTAL FLOODING IS POSSIBLE ALONG THE
EAST COAST.

WEDNESDAY EVENING...SOUTHERLY WINDS ARE EXPECTED AND ASTRONOMICAL
TIDES INCREASE ALONG THE SOUTH COAST. HIGH TIDE IN PROVIDENCE WILL
BE 5.2 FT. 925 MB LLJ STRENGTHENS TO 55-65 KTS WHICH COULD PUSH A
DECENT SURGE UP ALONG THE SOUTH COAST DURING THE TIME OF HIGH
TIDE. THINKING THAT MINOR COASTAL FLOODING COULD OCCUR BUT CANNOT
RULE OUT MODERATE ALONG THE SOUTH COAST...ESPECIALLY IF LLJ
CONTINUES TO STRENGTHEN.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO 7 AM EST
     TUESDAY FOR ANZ250.
     SMALL CRAFT ADVISORY FROM 10 PM THIS EVENING TO 7 AM EST
     TUESDAY FOR ANZ251-255.
     SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 7 AM EST
     TUESDAY FOR ANZ254.

&&

$$
SYNOPSIS...WTB/DUNTEN
NEAR TERM...DUNTEN
SHORT TERM...DUNTEN
LONG TERM...WTB
AVIATION...WTB/DUNTEN
MARINE...WTB/DUNTEN
TIDES/COASTAL FLOODING...




000
FXUS61 KBOX 220743
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
243 AM EST MON DEC 22 2014

.SYNOPSIS...
SCATTERED SNOW/RAIN SHOWERS WILL CONTINUE TODAY THANKS TO THE
ONSHORE FLOW. A WEAK LOW PRESSURE WILL MOVE ACROSS NEW ENGLAND
BRINGING A PERIOD OF PRECIPITATION VERY LATE MONDAY NIGHT AND
INTO TUESDAY. A MUCH STRONGER STORM PASSING WEST OF NEW ENGLAND
WILL BRING HEAVY RAINFALL...GUSTY WINDS AND COASTAL FLOODING
CONCERNS TO THE REGION WEDNESDAY AND WEDNESDAY NIGHT. DRY BUT VERY
WINDY CONDITIONS FOLLOW FOR CHRISTMAS DAY. HIGH PRESSURE BRINGS
DRY WEATHER FRIDAY. ANOTHER DEVELOPING SYSTEM MAY BRING RAIN AND
SNOW NEXT SUNDAY.

&&

.NEAR TERM /THROUGH TODAY/...

UPPER LEVEL RIDGE BUILDS AHEAD OF DIGGING MIDWEST TROUGH WITH
HIGH PRESSURE REMAINING ANCHORED OVER THE CANADIAN MARITIMES
THROUGH TONIGHT.

EASTERLY FLOW WILL CONTINUE ONSHORE ALLOWING FOR THE PROFILE TO
CONTINUE TO MOISTEN IN THE LOW LEVELS. IF THIS MOISTURE DEEPENS
ENOUGH THEN WE COULD SEE LIGHT SHOWERS DEVELOP ESP ACROSS THE MASS
EAST COASTLINE. OTHERWISE DRIZZLE MAY BE THE MAIN FACTOR AS THE
UPPER LEVELS ARE FAIRLY DRY. OVERALL TODAY WILL BE A COOL AND CLOUDY
DAY WITH HIGHS ONLY REACHING IN THE UPPER 30S TO LOW 40S AS CROSS
SECTIONS ARE VERY MOIST IN THE LOW LEVELS.

&&

.SHORT TERM /TONIGHT THROUGH 6 PM TUESDAY/...

TONIGHT INTO TOMORROW...

*LIGHT FREEZING RAIN IS POSSIBLE ACROSS THE INTERIOR NORTHWEST AND
  NORTHERN WORCESTER HILLS*

A WEAK AREA OF LOW PRESSURE DEVELOPS ALONG A WARM FRONT OFF THE MID
ATLANTIC...DRIFTING NORTHWARD TOWARD THE AREA. THIS LOW REMAINS WEAK
AS THE WARM FRONT MOVES SLOWLY NORTHWARD TONIGHT INTO TOMORROW.
DECENT WARM ADVECTION AHEAD OF THIS WAVE WITH SEVERAL HI-RES
GUIDANCE MODELS SHOWS A POTENTIAL FOR COLD AIR DAMMING ACROSS THE
INTERIOR INTO TUESDAY MORNING.  BIGGEST QUESTION WILL BE THE
MOISTURE POTENTIAL...IS THERE ENOUGH TO DEVELOP PRECIP ESP TONIGHT?
GUIDANCE DOES SHOW ENOUGH LIFT AHEAD OF APPROACHING SURFACE LOW PER
THE GFS/EC SO ANTICIPATE PRECIP TO DEVELOP AND OVERSPREAD ACROSS
SOUTHERN NEW ENGLAND. IF THIS PLAYS OUT WITH COLD AIR DAMMING AND
WARM AIR ADVECTION...THEN WE COULD SEE FREEZING RAIN/DRIZZLE ACROSS
THE INTERIOR NORTHWEST AND NORTHERN WORCESTER HILLS VERY LATE
TONIGHT INTO TUESDAY MORNING. A WINTER WEATHER ADVISORY MAY BE
NEEDED.

AS SURFACE LOW CONTINUES TO MOVE NORTHWARD...AND HIGH PRESSURE OVER
EASTERN CANADA...ANTICIPATE AN INCREASING LLJ. THIS SOUTHEASTERLY
JET WILL CONTINUE TO FEED MOISTURE INTO THE REGION AND WITH
SOUNDINGS SHOW A VERY SATURATED PROFILE COULD SEE NUMEROUS SHOWERS
WITH PERHAPS A FEW HEAVY DOWNPOURS. NOTICED GUIDANCE HAS
INCREASED THE QPF OVER THE PAST FEW DAYS. AS THE WEAK SURFACE LOW
MOVES NORTH OF SOUTHERN NEW ENGLAND...WARM FRONT WILL LIFT
NORTHWARD SO ALL PRECIP BY THE LATE MORNING WILL BE IN THE LIQUID
FORM.

WE COULD ALSO SEE SOME MINOR COASTAL FLOODING CONCERNS ON TUESDAY
WITH DUE EASTERLY FLOW INCREASING TO ABOUT 20 TO 25 MPH.  SEE BELOW
FOR MORE DETAILS.


&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
BIG PICTURE...

TUESDAY STARTS WITH UPPER RIDGES ON EACH COAST AND A DEEP UPPER
TROUGH/CLOSED LOW OVER THE PLAINS. BY WEDNESDAY THE CLOSED LOW
EJECTS NORTHEAST THROUGH LAKE SUPERIOR INTO CANADA. THIS SWEEPS THE
TROUGH AXIS EAST AND PASSES ACROSS NEW ENGLAND CHRISTMAS DAY.
ANOTHER SHORTWAVE MOVES ONSHORE IN THE PACIFIC NORTHWEST WEDNESDAY
AND PHASES WITH A SECOND DROPPING SOUTH FROM NORTHERN CANADA.  THIS
REESTABLISHES THE UPPER TROUGH OVER THE NORTHERN PLAINS/GREAT LAKES
SATURDAY.

CONTOUR HEIGHTS WILL BE ABOVE NORMAL MIDWEEK...TRENDING BELOW NORMAL
OVER THE WEEKEND AS THE SECOND UPPER TROUGH SHIFTS EAST. THIS POINTS
TO A COOLING TREND AFTER CHRISTMAS.

THE GFS AND ECMWF ARE SIMILAR IN HANDLING THE HOLIDAY STORM. THERE
ARE DIFFERENCES BETWEEN THE MODELS IN HANDLING THE SUNDAY SYSTEM. WE
USED A BLEND MOST OF THE LONG TERM PERIOD...BUT MANUALLY ADJUSTED
POPS FOR SUNDAY WITH LOW CONFIDENCE IN MODEL VALUES.

THE DAILIES...

TUESDAY... HIGH PRESSURE OVER THE MARITIMES WITH RIDGING DOWN THE
ATLANTIC COAST. COASTAL LOW PRESSURE WAVE DEVELOPS ALONG STALLED
WARM FRONT AND MOVES NORTH.  AS THE COASTAL LOW MOVES NORTH IT WILL
RUN UP AGAINST THE MARITIME HIGH. THIS WILL INCREASE THE LOW LEVEL
PRESSURE GRADIENT AND INCREASE THE LOW LEVEL SOUTHEAST WINDS.
RESULT...A SOUTHEAST LOW LEVEL JET RUNS OVER THE RIDGING ALONG THE
COASTAL PLAIN INDUCING LOW LEVEL LIFT. THE MOIST LAYER EXPANDS ABOVE
800 MB...NOT DEEP BUT DEEP ENOUGH FOR THE LIFT TO GENERATE LIGHT
PCPN. PTYPE WILL BE RAIN MOST PLACES...BUT THERE COULD BE SPOTS OF
LIGHT FREEZING RAIN IN NORTHWEST MASSACHUSETTS. WE WILL MAINTAIN
CHANCE POPS BUT INCREASE TO AROUND 50 PCT...THE HIGH END OF THE
CHANCE RANGE.

LOW LEVEL SOUTH JET MOVES UP THE COAST TUESDAY NIGHT REACHING THE
COOLER AIR OVER NEW ENGLAND AFTER MIDNIGHT AND BEFORE SUNRISE. THIS
WILL GENERATE ADDITIONAL LIFT AS WELL AS INCREASING AND DEEPENING
MOISTURE. THIS SUGGESTS INCREASING POPS OVERNIGHT.  TEMPERATURES
SHOULD REMAIN ABOVE FREEZING SO PTYPE SHOULD BE RAIN.

WEDNESDAY-THURSDAY... SOUTH 40-50 KNOT LOW LEVEL JET MOVES OVER NEW
ENGLAND WEDNESDAY GENERATING STRONG LIFT AND TRANSPORTING HIGH
VALUES OF PRECIPITABLE WATER INTO THAT LIFT. THE MOISTURE VALUES ARE
MORE THAN 3 STD DEVIATIONS ABOVE NORMAL FOR DECEMBER...AND ACTUALLY
NEAR THE MAXIMUM PREVIOUSLY OBSERVED VALUE. THIS SUGGESTS RAIN WITH
SOME HEAVY DOWNPOURS. COLD FRONT APPROACHES LATE WEDNESDAY NIGHT AND
CROSSES SOUTHERN NEW ENGLAND CHRISTMAS MORNING. THE FRONT WILL HAVE
DYNAMIC SUPPORT FROM A 140-150 KNOT UPPER JET. THE FOREWARD PROGRESS
OF THE FRONT WILL SLOW BECAUSE MOST OF THE MOTION IN THE UPPER JET
WILL BE PARALLEL TO THE FRONT. THIS WILL MEAN CONTINUED RAIN/HEAVY
RAIN THROUGH THE NIGHT INTO THURSDAY MORNING.

THE OBVIOUS CONCERN FOR THIS PERIOD WILL BE FLOODING FROM HEAVY
RAINFALL. RAIN AMOUNTS OF 2 TO 3 INCHES ARE EXPECTED. THIS SHOULD BE
SUFFICIENT FOR AT LEAST URBAN AND POOR DRAINAGE FLOODING. A FLOOD
WATCH MAY BE NEEDED.

A SECOND CONCERN WILL BE WIND. THE LOW LEVEL JET WEDNESDAY WILL BE
SOUTH 40-50 KNOTS...AND INCREASE TO 55-65 KNOTS WEDNESDAY NIGHT.
CONVENTIONAL MIXING WILL NOT BE DEEP...BUT HEAVY DOWNPOURS COULD
CREATE A MOIST ADIABATIC CHANNEL THAT BRINGS DOWN SOME STRONGER WIND
GUSTS. MODEL GRIDS ARE RATHER LIGHT ON WIND GUSTS...15 TO 30 KNOTS.
WE WILL MANUALLY ADJUST THESE VALUES UP TO 25-35 KNOTS OVER LAND AND
A LITTLE STRONGER OVER WATER.

A THIRD CONCERN WILL BE COASTAL FLOODING. MORE DETAILS ON THIS IN
THE TIDE/COASTAL FLOOD SECTION.

WINDS SHIFT TO WEST BEHIND THE FRONT ON CHRISTMAS DAY. THIS WILL
BRING DRIER AIR AND SO END THE RAINFALL. COLD ADVECTION WILL PROMOTE
MIXING TO NEAR 850 MB IN THE AFTERNOON AND TAP 25-35 KNOT WIND
GUSTS...POSSIBLY 40 KNOT GUSTS. A WIND ADVISORY MAY BE NEEDED FOR
THESE WEST WINDS THURSDAY.

FRIDAY THROUGH SUNDAY.... HIGH PRESSURE MOVES OVER THE REGION FRIDAY
BRINGING DRY WEATHER.  SHORTWAVE MOVING THROUGH THE GREAT LAKES
SWINGS A COLD FRONT THROUGH NEW ENGLAND SATURDAY. THE SURFACE
REFLECTION OF THE SHORTWAVE MOVES UP THE ST LAWRENCE VALLEY AND JET
SUPPORT WILL MOSTLY BE NORTH OF THE BORDER...SO PCPN WILL BE
LIMITED. QUESTION FOR SUNDAY WILL BE WHETHER A WAVE FORMS ON THE
DEPARTING COLD FRONT...IF SO IT MIGHT BRING PCPN TO NEW ENGLAND.
THE ECMWF THINKS SO BUT THE GFS DOES NOT. WE BROUGHT IN A CHANCE
OF RAIN AND SNOW SHOWERS.

&&

.AVIATION /08Z MONDAY THROUGH FRIDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH TUESDAY/...

TODAY...HIGH CONFIDENCE. DRIZZLE OR A FEW FLURRIES POSSIBLE
ACROSS EAST MASS TERMINALS. OTHERWISE ANY VFR CIGS WILL DROP TO
MVFR CONDITIONS THROUGHOUT THE DAY.

TONIGHT...MODERATE CONFIDENCE. MAINLY MVFR CONDITIONS CONTINUE IN
SCATTERED LIGHT SNOW SHOWERS. LIGHT FZRA POSSIBLE LATE MONDAY NIGHT
ACROSS NW MASSACHUSETTS.

TUESDAY...MODERATE CONFIDENCE. MVFR CONDITIONS MAY DROP TO IFR
WITHIN AND HEAVY RAIN FALL. VSBYS WILL BE REDUCED TO 5SM OR LESS
AS WELL.

KBOS TERMINAL...MODERATE CONFIDENCE. COULD SEE DRIZZLE LATER TODAY.

KBDL TERMINAL...MODERATE CONFIDENCE.

OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...MODERATE CONFIDENCE

LATE TUESDAY NIGHT-WEDNESDAY-THURSDAY... CONDITIONS LOWERING TO
IFR/LIFR IN RAIN/HEAVY RAIN. SOUTHEAST WINDS GUSTING 25 TO 35
KNOTS WEDNESDAY AND SOUTH WINDS SIMILAR SPEEDS WEDNESDAY
NIGHT...EXCEPT 30 TO 40 KNOTS CAPE COD AND ISLANDS. WINDS AT 2000
FEET MAY REACH 55 TO 65 KNOTS BY WEDNESDAY NIGHT CREATING LOW
LEVEL WIND SHEAR. ISOLATED THUNDERSTORMS WEDNESDAY AFTERNOON AND
NIGHT. COLD FRONT SWINGS THROUGH ON THURSDAY MORNING BRINGING A
WIND SHIFT TO WEST WITH GUSTS 30-40 KNOTS. CONDITIONS IMPROVE TO
VFR AFTER THE WIND SHIFT.

FRIDAY...VFR.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH TUESDAY/...MODERATE TO HIGH CONFIDENCE.

HIGH PRESSURE ACROSS QUEBEC AND THE MARITIMES WILL RESULT IN
PERSISTENT NORTHEASTERLY TO EASTERLY WINDS ACROSS THE WATERS THROUGH
TODAY. THIS WILL BUILD SEAS TO 5FT ON THE EASTERN WATERS DESPITE
WIND GUSTS UP TO 20 KNOTS. HAVE CONTINUED SCA.

APPROACHING SURFACE LOW PRESSURE FROM THE MID-ATLANTIC TONIGHT WILL
HELP INCREASE AN EASTERLY LLJ OVER THE WATER TOMORROW. THIS WILL
BUILD THE SEAS BETWEEN 5-8 FT. COULD SEE WIND GUSTS BETWEEN 20-30
KTS AS THE FRONT PASSES. SCA HAS BEEN EXPANDED ACCORDINGLY.

OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...MODERATE CONFIDENCE

WEDNESDAY-THURSDAY... SOUTH WINDS WITH FREQUENT GUSTS 35 TO 40
KNOTS BY WEDNESDAY AFTERNOON AND CONTINUING THROUGH THE NIGHT.
WINDS SHIFT WEST THURSDAY MORNING WITH SIMILAR SPEEDS THROUGH THE
AFTERNOON. SEAS WILL BUILD TO 7 TO 12 FEET ON THE EXPOSED WATERS
BY WEDNESDAY NIGHT AND THURSDAY. A GALE WARNING MAY BE NEEDED.

FRIDAY...WINDS DIMINISHING TO 25 KNOTS FRIDAY MORNING AND BELOW 25
KNOTS BY AFTERNOON.  SEAS LINGERING AT 5 TO 7 FEET ON THE EXPOSED
WATERS. A SMALL CRAFT ADVISORY MAY BE NEEDED.

&&

.TIDES/COASTAL FLOODING...
HIGH ASTRONOMICAL TIDES WILL OCCUR TUESDAY THROUGH THURSDAY.

TUESDAY...HIGH TIDE AT BOSTON WILL BE 11.6 FT. WINDS WILL BE FROM
THE EAST...SO THERE WILL BE ONSHORE FLOW DURING THIS HIGH TIDE
ALLOWING FOR MINOR SPLASHOVER. IF WINDS INCREASE THEN COULD SEE
SOME POCKETS OF MINOR COASTAL FLOODING.

WEDNESDAY...WINDS SHIFT TO A MORE SOUTHEASTERLY FLOW DURING THE DAY
AND INCREASE QUICKLY AS AN APPROACHING SYSTEM BRINGS PRESSURE
FALLS OF 1 MB/HR. THE WEDNESDAY AFTERNOON HIGH TIDE IN BOSTON IS
11.7 FT AND STRONG SOUTHEASTERLY WINDS WILL BE JUST OFFSHORE.
RIGHT NOW BELIEVE MINOR COASTAL FLOODING IS POSSIBLE ALONG THE
EAST COAST.

WEDNESDAY EVENING...SOUTHERLY WINDS ARE EXPECTED AND ASTRONOMICAL
TIDES INCREASE ALONG THE SOUTH COAST. HIGH TIDE IN PROVIDENCE WILL
BE 5.2 FT. 925 MB LLJ STRENGTHENS TO 55-65 KTS WHICH COULD PUSH A
DECENT SURGE UP ALONG THE SOUTH COAST DURING THE TIME OF HIGH
TIDE. THINKING THAT MINOR COASTAL FLOODING COULD OCCUR BUT CANNOT
RULE OUT MODERATE ALONG THE SOUTH COAST...ESPECIALLY IF LLJ
CONTINUES TO STRENGTHEN.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO 7 AM EST
     TUESDAY FOR ANZ250.
     SMALL CRAFT ADVISORY FROM 10 PM THIS EVENING TO 7 AM EST
     TUESDAY FOR ANZ251-255.
     SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 7 AM EST
     TUESDAY FOR ANZ254.

&&

$$
SYNOPSIS...WTB/DUNTEN
NEAR TERM...DUNTEN
SHORT TERM...DUNTEN
LONG TERM...WTB
AVIATION...WTB/DUNTEN
MARINE...WTB/DUNTEN
TIDES/COASTAL FLOODING...



000
FXUS61 KBOX 220743
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
243 AM EST MON DEC 22 2014

.SYNOPSIS...
SCATTERED SNOW/RAIN SHOWERS WILL CONTINUE TODAY THANKS TO THE
ONSHORE FLOW. A WEAK LOW PRESSURE WILL MOVE ACROSS NEW ENGLAND
BRINGING A PERIOD OF PRECIPITATION VERY LATE MONDAY NIGHT AND
INTO TUESDAY. A MUCH STRONGER STORM PASSING WEST OF NEW ENGLAND
WILL BRING HEAVY RAINFALL...GUSTY WINDS AND COASTAL FLOODING
CONCERNS TO THE REGION WEDNESDAY AND WEDNESDAY NIGHT. DRY BUT VERY
WINDY CONDITIONS FOLLOW FOR CHRISTMAS DAY. HIGH PRESSURE BRINGS
DRY WEATHER FRIDAY. ANOTHER DEVELOPING SYSTEM MAY BRING RAIN AND
SNOW NEXT SUNDAY.

&&

.NEAR TERM /THROUGH TODAY/...

UPPER LEVEL RIDGE BUILDS AHEAD OF DIGGING MIDWEST TROUGH WITH
HIGH PRESSURE REMAINING ANCHORED OVER THE CANADIAN MARITIMES
THROUGH TONIGHT.

EASTERLY FLOW WILL CONTINUE ONSHORE ALLOWING FOR THE PROFILE TO
CONTINUE TO MOISTEN IN THE LOW LEVELS. IF THIS MOISTURE DEEPENS
ENOUGH THEN WE COULD SEE LIGHT SHOWERS DEVELOP ESP ACROSS THE MASS
EAST COASTLINE. OTHERWISE DRIZZLE MAY BE THE MAIN FACTOR AS THE
UPPER LEVELS ARE FAIRLY DRY. OVERALL TODAY WILL BE A COOL AND CLOUDY
DAY WITH HIGHS ONLY REACHING IN THE UPPER 30S TO LOW 40S AS CROSS
SECTIONS ARE VERY MOIST IN THE LOW LEVELS.

&&

.SHORT TERM /TONIGHT THROUGH 6 PM TUESDAY/...

TONIGHT INTO TOMORROW...

*LIGHT FREEZING RAIN IS POSSIBLE ACROSS THE INTERIOR NORTHWEST AND
  NORTHERN WORCESTER HILLS*

A WEAK AREA OF LOW PRESSURE DEVELOPS ALONG A WARM FRONT OFF THE MID
ATLANTIC...DRIFTING NORTHWARD TOWARD THE AREA. THIS LOW REMAINS WEAK
AS THE WARM FRONT MOVES SLOWLY NORTHWARD TONIGHT INTO TOMORROW.
DECENT WARM ADVECTION AHEAD OF THIS WAVE WITH SEVERAL HI-RES
GUIDANCE MODELS SHOWS A POTENTIAL FOR COLD AIR DAMMING ACROSS THE
INTERIOR INTO TUESDAY MORNING.  BIGGEST QUESTION WILL BE THE
MOISTURE POTENTIAL...IS THERE ENOUGH TO DEVELOP PRECIP ESP TONIGHT?
GUIDANCE DOES SHOW ENOUGH LIFT AHEAD OF APPROACHING SURFACE LOW PER
THE GFS/EC SO ANTICIPATE PRECIP TO DEVELOP AND OVERSPREAD ACROSS
SOUTHERN NEW ENGLAND. IF THIS PLAYS OUT WITH COLD AIR DAMMING AND
WARM AIR ADVECTION...THEN WE COULD SEE FREEZING RAIN/DRIZZLE ACROSS
THE INTERIOR NORTHWEST AND NORTHERN WORCESTER HILLS VERY LATE
TONIGHT INTO TUESDAY MORNING. A WINTER WEATHER ADVISORY MAY BE
NEEDED.

AS SURFACE LOW CONTINUES TO MOVE NORTHWARD...AND HIGH PRESSURE OVER
EASTERN CANADA...ANTICIPATE AN INCREASING LLJ. THIS SOUTHEASTERLY
JET WILL CONTINUE TO FEED MOISTURE INTO THE REGION AND WITH
SOUNDINGS SHOW A VERY SATURATED PROFILE COULD SEE NUMEROUS SHOWERS
WITH PERHAPS A FEW HEAVY DOWNPOURS. NOTICED GUIDANCE HAS
INCREASED THE QPF OVER THE PAST FEW DAYS. AS THE WEAK SURFACE LOW
MOVES NORTH OF SOUTHERN NEW ENGLAND...WARM FRONT WILL LIFT
NORTHWARD SO ALL PRECIP BY THE LATE MORNING WILL BE IN THE LIQUID
FORM.

WE COULD ALSO SEE SOME MINOR COASTAL FLOODING CONCERNS ON TUESDAY
WITH DUE EASTERLY FLOW INCREASING TO ABOUT 20 TO 25 MPH.  SEE BELOW
FOR MORE DETAILS.


&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
BIG PICTURE...

TUESDAY STARTS WITH UPPER RIDGES ON EACH COAST AND A DEEP UPPER
TROUGH/CLOSED LOW OVER THE PLAINS. BY WEDNESDAY THE CLOSED LOW
EJECTS NORTHEAST THROUGH LAKE SUPERIOR INTO CANADA. THIS SWEEPS THE
TROUGH AXIS EAST AND PASSES ACROSS NEW ENGLAND CHRISTMAS DAY.
ANOTHER SHORTWAVE MOVES ONSHORE IN THE PACIFIC NORTHWEST WEDNESDAY
AND PHASES WITH A SECOND DROPPING SOUTH FROM NORTHERN CANADA.  THIS
REESTABLISHES THE UPPER TROUGH OVER THE NORTHERN PLAINS/GREAT LAKES
SATURDAY.

CONTOUR HEIGHTS WILL BE ABOVE NORMAL MIDWEEK...TRENDING BELOW NORMAL
OVER THE WEEKEND AS THE SECOND UPPER TROUGH SHIFTS EAST. THIS POINTS
TO A COOLING TREND AFTER CHRISTMAS.

THE GFS AND ECMWF ARE SIMILAR IN HANDLING THE HOLIDAY STORM. THERE
ARE DIFFERENCES BETWEEN THE MODELS IN HANDLING THE SUNDAY SYSTEM. WE
USED A BLEND MOST OF THE LONG TERM PERIOD...BUT MANUALLY ADJUSTED
POPS FOR SUNDAY WITH LOW CONFIDENCE IN MODEL VALUES.

THE DAILIES...

TUESDAY... HIGH PRESSURE OVER THE MARITIMES WITH RIDGING DOWN THE
ATLANTIC COAST. COASTAL LOW PRESSURE WAVE DEVELOPS ALONG STALLED
WARM FRONT AND MOVES NORTH.  AS THE COASTAL LOW MOVES NORTH IT WILL
RUN UP AGAINST THE MARITIME HIGH. THIS WILL INCREASE THE LOW LEVEL
PRESSURE GRADIENT AND INCREASE THE LOW LEVEL SOUTHEAST WINDS.
RESULT...A SOUTHEAST LOW LEVEL JET RUNS OVER THE RIDGING ALONG THE
COASTAL PLAIN INDUCING LOW LEVEL LIFT. THE MOIST LAYER EXPANDS ABOVE
800 MB...NOT DEEP BUT DEEP ENOUGH FOR THE LIFT TO GENERATE LIGHT
PCPN. PTYPE WILL BE RAIN MOST PLACES...BUT THERE COULD BE SPOTS OF
LIGHT FREEZING RAIN IN NORTHWEST MASSACHUSETTS. WE WILL MAINTAIN
CHANCE POPS BUT INCREASE TO AROUND 50 PCT...THE HIGH END OF THE
CHANCE RANGE.

LOW LEVEL SOUTH JET MOVES UP THE COAST TUESDAY NIGHT REACHING THE
COOLER AIR OVER NEW ENGLAND AFTER MIDNIGHT AND BEFORE SUNRISE. THIS
WILL GENERATE ADDITIONAL LIFT AS WELL AS INCREASING AND DEEPENING
MOISTURE. THIS SUGGESTS INCREASING POPS OVERNIGHT.  TEMPERATURES
SHOULD REMAIN ABOVE FREEZING SO PTYPE SHOULD BE RAIN.

WEDNESDAY-THURSDAY... SOUTH 40-50 KNOT LOW LEVEL JET MOVES OVER NEW
ENGLAND WEDNESDAY GENERATING STRONG LIFT AND TRANSPORTING HIGH
VALUES OF PRECIPITABLE WATER INTO THAT LIFT. THE MOISTURE VALUES ARE
MORE THAN 3 STD DEVIATIONS ABOVE NORMAL FOR DECEMBER...AND ACTUALLY
NEAR THE MAXIMUM PREVIOUSLY OBSERVED VALUE. THIS SUGGESTS RAIN WITH
SOME HEAVY DOWNPOURS. COLD FRONT APPROACHES LATE WEDNESDAY NIGHT AND
CROSSES SOUTHERN NEW ENGLAND CHRISTMAS MORNING. THE FRONT WILL HAVE
DYNAMIC SUPPORT FROM A 140-150 KNOT UPPER JET. THE FOREWARD PROGRESS
OF THE FRONT WILL SLOW BECAUSE MOST OF THE MOTION IN THE UPPER JET
WILL BE PARALLEL TO THE FRONT. THIS WILL MEAN CONTINUED RAIN/HEAVY
RAIN THROUGH THE NIGHT INTO THURSDAY MORNING.

THE OBVIOUS CONCERN FOR THIS PERIOD WILL BE FLOODING FROM HEAVY
RAINFALL. RAIN AMOUNTS OF 2 TO 3 INCHES ARE EXPECTED. THIS SHOULD BE
SUFFICIENT FOR AT LEAST URBAN AND POOR DRAINAGE FLOODING. A FLOOD
WATCH MAY BE NEEDED.

A SECOND CONCERN WILL BE WIND. THE LOW LEVEL JET WEDNESDAY WILL BE
SOUTH 40-50 KNOTS...AND INCREASE TO 55-65 KNOTS WEDNESDAY NIGHT.
CONVENTIONAL MIXING WILL NOT BE DEEP...BUT HEAVY DOWNPOURS COULD
CREATE A MOIST ADIABATIC CHANNEL THAT BRINGS DOWN SOME STRONGER WIND
GUSTS. MODEL GRIDS ARE RATHER LIGHT ON WIND GUSTS...15 TO 30 KNOTS.
WE WILL MANUALLY ADJUST THESE VALUES UP TO 25-35 KNOTS OVER LAND AND
A LITTLE STRONGER OVER WATER.

A THIRD CONCERN WILL BE COASTAL FLOODING. MORE DETAILS ON THIS IN
THE TIDE/COASTAL FLOOD SECTION.

WINDS SHIFT TO WEST BEHIND THE FRONT ON CHRISTMAS DAY. THIS WILL
BRING DRIER AIR AND SO END THE RAINFALL. COLD ADVECTION WILL PROMOTE
MIXING TO NEAR 850 MB IN THE AFTERNOON AND TAP 25-35 KNOT WIND
GUSTS...POSSIBLY 40 KNOT GUSTS. A WIND ADVISORY MAY BE NEEDED FOR
THESE WEST WINDS THURSDAY.

FRIDAY THROUGH SUNDAY.... HIGH PRESSURE MOVES OVER THE REGION FRIDAY
BRINGING DRY WEATHER.  SHORTWAVE MOVING THROUGH THE GREAT LAKES
SWINGS A COLD FRONT THROUGH NEW ENGLAND SATURDAY. THE SURFACE
REFLECTION OF THE SHORTWAVE MOVES UP THE ST LAWRENCE VALLEY AND JET
SUPPORT WILL MOSTLY BE NORTH OF THE BORDER...SO PCPN WILL BE
LIMITED. QUESTION FOR SUNDAY WILL BE WHETHER A WAVE FORMS ON THE
DEPARTING COLD FRONT...IF SO IT MIGHT BRING PCPN TO NEW ENGLAND.
THE ECMWF THINKS SO BUT THE GFS DOES NOT. WE BROUGHT IN A CHANCE
OF RAIN AND SNOW SHOWERS.

&&

.AVIATION /08Z MONDAY THROUGH FRIDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH TUESDAY/...

TODAY...HIGH CONFIDENCE. DRIZZLE OR A FEW FLURRIES POSSIBLE
ACROSS EAST MASS TERMINALS. OTHERWISE ANY VFR CIGS WILL DROP TO
MVFR CONDITIONS THROUGHOUT THE DAY.

TONIGHT...MODERATE CONFIDENCE. MAINLY MVFR CONDITIONS CONTINUE IN
SCATTERED LIGHT SNOW SHOWERS. LIGHT FZRA POSSIBLE LATE MONDAY NIGHT
ACROSS NW MASSACHUSETTS.

TUESDAY...MODERATE CONFIDENCE. MVFR CONDITIONS MAY DROP TO IFR
WITHIN AND HEAVY RAIN FALL. VSBYS WILL BE REDUCED TO 5SM OR LESS
AS WELL.

KBOS TERMINAL...MODERATE CONFIDENCE. COULD SEE DRIZZLE LATER TODAY.

KBDL TERMINAL...MODERATE CONFIDENCE.

OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...MODERATE CONFIDENCE

LATE TUESDAY NIGHT-WEDNESDAY-THURSDAY... CONDITIONS LOWERING TO
IFR/LIFR IN RAIN/HEAVY RAIN. SOUTHEAST WINDS GUSTING 25 TO 35
KNOTS WEDNESDAY AND SOUTH WINDS SIMILAR SPEEDS WEDNESDAY
NIGHT...EXCEPT 30 TO 40 KNOTS CAPE COD AND ISLANDS. WINDS AT 2000
FEET MAY REACH 55 TO 65 KNOTS BY WEDNESDAY NIGHT CREATING LOW
LEVEL WIND SHEAR. ISOLATED THUNDERSTORMS WEDNESDAY AFTERNOON AND
NIGHT. COLD FRONT SWINGS THROUGH ON THURSDAY MORNING BRINGING A
WIND SHIFT TO WEST WITH GUSTS 30-40 KNOTS. CONDITIONS IMPROVE TO
VFR AFTER THE WIND SHIFT.

FRIDAY...VFR.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH TUESDAY/...MODERATE TO HIGH CONFIDENCE.

HIGH PRESSURE ACROSS QUEBEC AND THE MARITIMES WILL RESULT IN
PERSISTENT NORTHEASTERLY TO EASTERLY WINDS ACROSS THE WATERS THROUGH
TODAY. THIS WILL BUILD SEAS TO 5FT ON THE EASTERN WATERS DESPITE
WIND GUSTS UP TO 20 KNOTS. HAVE CONTINUED SCA.

APPROACHING SURFACE LOW PRESSURE FROM THE MID-ATLANTIC TONIGHT WILL
HELP INCREASE AN EASTERLY LLJ OVER THE WATER TOMORROW. THIS WILL
BUILD THE SEAS BETWEEN 5-8 FT. COULD SEE WIND GUSTS BETWEEN 20-30
KTS AS THE FRONT PASSES. SCA HAS BEEN EXPANDED ACCORDINGLY.

OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...MODERATE CONFIDENCE

WEDNESDAY-THURSDAY... SOUTH WINDS WITH FREQUENT GUSTS 35 TO 40
KNOTS BY WEDNESDAY AFTERNOON AND CONTINUING THROUGH THE NIGHT.
WINDS SHIFT WEST THURSDAY MORNING WITH SIMILAR SPEEDS THROUGH THE
AFTERNOON. SEAS WILL BUILD TO 7 TO 12 FEET ON THE EXPOSED WATERS
BY WEDNESDAY NIGHT AND THURSDAY. A GALE WARNING MAY BE NEEDED.

FRIDAY...WINDS DIMINISHING TO 25 KNOTS FRIDAY MORNING AND BELOW 25
KNOTS BY AFTERNOON.  SEAS LINGERING AT 5 TO 7 FEET ON THE EXPOSED
WATERS. A SMALL CRAFT ADVISORY MAY BE NEEDED.

&&

.TIDES/COASTAL FLOODING...
HIGH ASTRONOMICAL TIDES WILL OCCUR TUESDAY THROUGH THURSDAY.

TUESDAY...HIGH TIDE AT BOSTON WILL BE 11.6 FT. WINDS WILL BE FROM
THE EAST...SO THERE WILL BE ONSHORE FLOW DURING THIS HIGH TIDE
ALLOWING FOR MINOR SPLASHOVER. IF WINDS INCREASE THEN COULD SEE
SOME POCKETS OF MINOR COASTAL FLOODING.

WEDNESDAY...WINDS SHIFT TO A MORE SOUTHEASTERLY FLOW DURING THE DAY
AND INCREASE QUICKLY AS AN APPROACHING SYSTEM BRINGS PRESSURE
FALLS OF 1 MB/HR. THE WEDNESDAY AFTERNOON HIGH TIDE IN BOSTON IS
11.7 FT AND STRONG SOUTHEASTERLY WINDS WILL BE JUST OFFSHORE.
RIGHT NOW BELIEVE MINOR COASTAL FLOODING IS POSSIBLE ALONG THE
EAST COAST.

WEDNESDAY EVENING...SOUTHERLY WINDS ARE EXPECTED AND ASTRONOMICAL
TIDES INCREASE ALONG THE SOUTH COAST. HIGH TIDE IN PROVIDENCE WILL
BE 5.2 FT. 925 MB LLJ STRENGTHENS TO 55-65 KTS WHICH COULD PUSH A
DECENT SURGE UP ALONG THE SOUTH COAST DURING THE TIME OF HIGH
TIDE. THINKING THAT MINOR COASTAL FLOODING COULD OCCUR BUT CANNOT
RULE OUT MODERATE ALONG THE SOUTH COAST...ESPECIALLY IF LLJ
CONTINUES TO STRENGTHEN.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO 7 AM EST
     TUESDAY FOR ANZ250.
     SMALL CRAFT ADVISORY FROM 10 PM THIS EVENING TO 7 AM EST
     TUESDAY FOR ANZ251-255.
     SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 7 AM EST
     TUESDAY FOR ANZ254.

&&

$$
SYNOPSIS...WTB/DUNTEN
NEAR TERM...DUNTEN
SHORT TERM...DUNTEN
LONG TERM...WTB
AVIATION...WTB/DUNTEN
MARINE...WTB/DUNTEN
TIDES/COASTAL FLOODING...



000
FXUS61 KBOX 220743
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
243 AM EST MON DEC 22 2014

.SYNOPSIS...
SCATTERED SNOW/RAIN SHOWERS WILL CONTINUE TODAY THANKS TO THE
ONSHORE FLOW. A WEAK LOW PRESSURE WILL MOVE ACROSS NEW ENGLAND
BRINGING A PERIOD OF PRECIPITATION VERY LATE MONDAY NIGHT AND
INTO TUESDAY. A MUCH STRONGER STORM PASSING WEST OF NEW ENGLAND
WILL BRING HEAVY RAINFALL...GUSTY WINDS AND COASTAL FLOODING
CONCERNS TO THE REGION WEDNESDAY AND WEDNESDAY NIGHT. DRY BUT VERY
WINDY CONDITIONS FOLLOW FOR CHRISTMAS DAY. HIGH PRESSURE BRINGS
DRY WEATHER FRIDAY. ANOTHER DEVELOPING SYSTEM MAY BRING RAIN AND
SNOW NEXT SUNDAY.

&&

.NEAR TERM /THROUGH TODAY/...

UPPER LEVEL RIDGE BUILDS AHEAD OF DIGGING MIDWEST TROUGH WITH
HIGH PRESSURE REMAINING ANCHORED OVER THE CANADIAN MARITIMES
THROUGH TONIGHT.

EASTERLY FLOW WILL CONTINUE ONSHORE ALLOWING FOR THE PROFILE TO
CONTINUE TO MOISTEN IN THE LOW LEVELS. IF THIS MOISTURE DEEPENS
ENOUGH THEN WE COULD SEE LIGHT SHOWERS DEVELOP ESP ACROSS THE MASS
EAST COASTLINE. OTHERWISE DRIZZLE MAY BE THE MAIN FACTOR AS THE
UPPER LEVELS ARE FAIRLY DRY. OVERALL TODAY WILL BE A COOL AND CLOUDY
DAY WITH HIGHS ONLY REACHING IN THE UPPER 30S TO LOW 40S AS CROSS
SECTIONS ARE VERY MOIST IN THE LOW LEVELS.

&&

.SHORT TERM /TONIGHT THROUGH 6 PM TUESDAY/...

TONIGHT INTO TOMORROW...

*LIGHT FREEZING RAIN IS POSSIBLE ACROSS THE INTERIOR NORTHWEST AND
  NORTHERN WORCESTER HILLS*

A WEAK AREA OF LOW PRESSURE DEVELOPS ALONG A WARM FRONT OFF THE MID
ATLANTIC...DRIFTING NORTHWARD TOWARD THE AREA. THIS LOW REMAINS WEAK
AS THE WARM FRONT MOVES SLOWLY NORTHWARD TONIGHT INTO TOMORROW.
DECENT WARM ADVECTION AHEAD OF THIS WAVE WITH SEVERAL HI-RES
GUIDANCE MODELS SHOWS A POTENTIAL FOR COLD AIR DAMMING ACROSS THE
INTERIOR INTO TUESDAY MORNING.  BIGGEST QUESTION WILL BE THE
MOISTURE POTENTIAL...IS THERE ENOUGH TO DEVELOP PRECIP ESP TONIGHT?
GUIDANCE DOES SHOW ENOUGH LIFT AHEAD OF APPROACHING SURFACE LOW PER
THE GFS/EC SO ANTICIPATE PRECIP TO DEVELOP AND OVERSPREAD ACROSS
SOUTHERN NEW ENGLAND. IF THIS PLAYS OUT WITH COLD AIR DAMMING AND
WARM AIR ADVECTION...THEN WE COULD SEE FREEZING RAIN/DRIZZLE ACROSS
THE INTERIOR NORTHWEST AND NORTHERN WORCESTER HILLS VERY LATE
TONIGHT INTO TUESDAY MORNING. A WINTER WEATHER ADVISORY MAY BE
NEEDED.

AS SURFACE LOW CONTINUES TO MOVE NORTHWARD...AND HIGH PRESSURE OVER
EASTERN CANADA...ANTICIPATE AN INCREASING LLJ. THIS SOUTHEASTERLY
JET WILL CONTINUE TO FEED MOISTURE INTO THE REGION AND WITH
SOUNDINGS SHOW A VERY SATURATED PROFILE COULD SEE NUMEROUS SHOWERS
WITH PERHAPS A FEW HEAVY DOWNPOURS. NOTICED GUIDANCE HAS
INCREASED THE QPF OVER THE PAST FEW DAYS. AS THE WEAK SURFACE LOW
MOVES NORTH OF SOUTHERN NEW ENGLAND...WARM FRONT WILL LIFT
NORTHWARD SO ALL PRECIP BY THE LATE MORNING WILL BE IN THE LIQUID
FORM.

WE COULD ALSO SEE SOME MINOR COASTAL FLOODING CONCERNS ON TUESDAY
WITH DUE EASTERLY FLOW INCREASING TO ABOUT 20 TO 25 MPH.  SEE BELOW
FOR MORE DETAILS.


&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
BIG PICTURE...

TUESDAY STARTS WITH UPPER RIDGES ON EACH COAST AND A DEEP UPPER
TROUGH/CLOSED LOW OVER THE PLAINS. BY WEDNESDAY THE CLOSED LOW
EJECTS NORTHEAST THROUGH LAKE SUPERIOR INTO CANADA. THIS SWEEPS THE
TROUGH AXIS EAST AND PASSES ACROSS NEW ENGLAND CHRISTMAS DAY.
ANOTHER SHORTWAVE MOVES ONSHORE IN THE PACIFIC NORTHWEST WEDNESDAY
AND PHASES WITH A SECOND DROPPING SOUTH FROM NORTHERN CANADA.  THIS
REESTABLISHES THE UPPER TROUGH OVER THE NORTHERN PLAINS/GREAT LAKES
SATURDAY.

CONTOUR HEIGHTS WILL BE ABOVE NORMAL MIDWEEK...TRENDING BELOW NORMAL
OVER THE WEEKEND AS THE SECOND UPPER TROUGH SHIFTS EAST. THIS POINTS
TO A COOLING TREND AFTER CHRISTMAS.

THE GFS AND ECMWF ARE SIMILAR IN HANDLING THE HOLIDAY STORM. THERE
ARE DIFFERENCES BETWEEN THE MODELS IN HANDLING THE SUNDAY SYSTEM. WE
USED A BLEND MOST OF THE LONG TERM PERIOD...BUT MANUALLY ADJUSTED
POPS FOR SUNDAY WITH LOW CONFIDENCE IN MODEL VALUES.

THE DAILIES...

TUESDAY... HIGH PRESSURE OVER THE MARITIMES WITH RIDGING DOWN THE
ATLANTIC COAST. COASTAL LOW PRESSURE WAVE DEVELOPS ALONG STALLED
WARM FRONT AND MOVES NORTH.  AS THE COASTAL LOW MOVES NORTH IT WILL
RUN UP AGAINST THE MARITIME HIGH. THIS WILL INCREASE THE LOW LEVEL
PRESSURE GRADIENT AND INCREASE THE LOW LEVEL SOUTHEAST WINDS.
RESULT...A SOUTHEAST LOW LEVEL JET RUNS OVER THE RIDGING ALONG THE
COASTAL PLAIN INDUCING LOW LEVEL LIFT. THE MOIST LAYER EXPANDS ABOVE
800 MB...NOT DEEP BUT DEEP ENOUGH FOR THE LIFT TO GENERATE LIGHT
PCPN. PTYPE WILL BE RAIN MOST PLACES...BUT THERE COULD BE SPOTS OF
LIGHT FREEZING RAIN IN NORTHWEST MASSACHUSETTS. WE WILL MAINTAIN
CHANCE POPS BUT INCREASE TO AROUND 50 PCT...THE HIGH END OF THE
CHANCE RANGE.

LOW LEVEL SOUTH JET MOVES UP THE COAST TUESDAY NIGHT REACHING THE
COOLER AIR OVER NEW ENGLAND AFTER MIDNIGHT AND BEFORE SUNRISE. THIS
WILL GENERATE ADDITIONAL LIFT AS WELL AS INCREASING AND DEEPENING
MOISTURE. THIS SUGGESTS INCREASING POPS OVERNIGHT.  TEMPERATURES
SHOULD REMAIN ABOVE FREEZING SO PTYPE SHOULD BE RAIN.

WEDNESDAY-THURSDAY... SOUTH 40-50 KNOT LOW LEVEL JET MOVES OVER NEW
ENGLAND WEDNESDAY GENERATING STRONG LIFT AND TRANSPORTING HIGH
VALUES OF PRECIPITABLE WATER INTO THAT LIFT. THE MOISTURE VALUES ARE
MORE THAN 3 STD DEVIATIONS ABOVE NORMAL FOR DECEMBER...AND ACTUALLY
NEAR THE MAXIMUM PREVIOUSLY OBSERVED VALUE. THIS SUGGESTS RAIN WITH
SOME HEAVY DOWNPOURS. COLD FRONT APPROACHES LATE WEDNESDAY NIGHT AND
CROSSES SOUTHERN NEW ENGLAND CHRISTMAS MORNING. THE FRONT WILL HAVE
DYNAMIC SUPPORT FROM A 140-150 KNOT UPPER JET. THE FOREWARD PROGRESS
OF THE FRONT WILL SLOW BECAUSE MOST OF THE MOTION IN THE UPPER JET
WILL BE PARALLEL TO THE FRONT. THIS WILL MEAN CONTINUED RAIN/HEAVY
RAIN THROUGH THE NIGHT INTO THURSDAY MORNING.

THE OBVIOUS CONCERN FOR THIS PERIOD WILL BE FLOODING FROM HEAVY
RAINFALL. RAIN AMOUNTS OF 2 TO 3 INCHES ARE EXPECTED. THIS SHOULD BE
SUFFICIENT FOR AT LEAST URBAN AND POOR DRAINAGE FLOODING. A FLOOD
WATCH MAY BE NEEDED.

A SECOND CONCERN WILL BE WIND. THE LOW LEVEL JET WEDNESDAY WILL BE
SOUTH 40-50 KNOTS...AND INCREASE TO 55-65 KNOTS WEDNESDAY NIGHT.
CONVENTIONAL MIXING WILL NOT BE DEEP...BUT HEAVY DOWNPOURS COULD
CREATE A MOIST ADIABATIC CHANNEL THAT BRINGS DOWN SOME STRONGER WIND
GUSTS. MODEL GRIDS ARE RATHER LIGHT ON WIND GUSTS...15 TO 30 KNOTS.
WE WILL MANUALLY ADJUST THESE VALUES UP TO 25-35 KNOTS OVER LAND AND
A LITTLE STRONGER OVER WATER.

A THIRD CONCERN WILL BE COASTAL FLOODING. MORE DETAILS ON THIS IN
THE TIDE/COASTAL FLOOD SECTION.

WINDS SHIFT TO WEST BEHIND THE FRONT ON CHRISTMAS DAY. THIS WILL
BRING DRIER AIR AND SO END THE RAINFALL. COLD ADVECTION WILL PROMOTE
MIXING TO NEAR 850 MB IN THE AFTERNOON AND TAP 25-35 KNOT WIND
GUSTS...POSSIBLY 40 KNOT GUSTS. A WIND ADVISORY MAY BE NEEDED FOR
THESE WEST WINDS THURSDAY.

FRIDAY THROUGH SUNDAY.... HIGH PRESSURE MOVES OVER THE REGION FRIDAY
BRINGING DRY WEATHER.  SHORTWAVE MOVING THROUGH THE GREAT LAKES
SWINGS A COLD FRONT THROUGH NEW ENGLAND SATURDAY. THE SURFACE
REFLECTION OF THE SHORTWAVE MOVES UP THE ST LAWRENCE VALLEY AND JET
SUPPORT WILL MOSTLY BE NORTH OF THE BORDER...SO PCPN WILL BE
LIMITED. QUESTION FOR SUNDAY WILL BE WHETHER A WAVE FORMS ON THE
DEPARTING COLD FRONT...IF SO IT MIGHT BRING PCPN TO NEW ENGLAND.
THE ECMWF THINKS SO BUT THE GFS DOES NOT. WE BROUGHT IN A CHANCE
OF RAIN AND SNOW SHOWERS.

&&

.AVIATION /08Z MONDAY THROUGH FRIDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH TUESDAY/...

TODAY...HIGH CONFIDENCE. DRIZZLE OR A FEW FLURRIES POSSIBLE
ACROSS EAST MASS TERMINALS. OTHERWISE ANY VFR CIGS WILL DROP TO
MVFR CONDITIONS THROUGHOUT THE DAY.

TONIGHT...MODERATE CONFIDENCE. MAINLY MVFR CONDITIONS CONTINUE IN
SCATTERED LIGHT SNOW SHOWERS. LIGHT FZRA POSSIBLE LATE MONDAY NIGHT
ACROSS NW MASSACHUSETTS.

TUESDAY...MODERATE CONFIDENCE. MVFR CONDITIONS MAY DROP TO IFR
WITHIN AND HEAVY RAIN FALL. VSBYS WILL BE REDUCED TO 5SM OR LESS
AS WELL.

KBOS TERMINAL...MODERATE CONFIDENCE. COULD SEE DRIZZLE LATER TODAY.

KBDL TERMINAL...MODERATE CONFIDENCE.

OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...MODERATE CONFIDENCE

LATE TUESDAY NIGHT-WEDNESDAY-THURSDAY... CONDITIONS LOWERING TO
IFR/LIFR IN RAIN/HEAVY RAIN. SOUTHEAST WINDS GUSTING 25 TO 35
KNOTS WEDNESDAY AND SOUTH WINDS SIMILAR SPEEDS WEDNESDAY
NIGHT...EXCEPT 30 TO 40 KNOTS CAPE COD AND ISLANDS. WINDS AT 2000
FEET MAY REACH 55 TO 65 KNOTS BY WEDNESDAY NIGHT CREATING LOW
LEVEL WIND SHEAR. ISOLATED THUNDERSTORMS WEDNESDAY AFTERNOON AND
NIGHT. COLD FRONT SWINGS THROUGH ON THURSDAY MORNING BRINGING A
WIND SHIFT TO WEST WITH GUSTS 30-40 KNOTS. CONDITIONS IMPROVE TO
VFR AFTER THE WIND SHIFT.

FRIDAY...VFR.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH TUESDAY/...MODERATE TO HIGH CONFIDENCE.

HIGH PRESSURE ACROSS QUEBEC AND THE MARITIMES WILL RESULT IN
PERSISTENT NORTHEASTERLY TO EASTERLY WINDS ACROSS THE WATERS THROUGH
TODAY. THIS WILL BUILD SEAS TO 5FT ON THE EASTERN WATERS DESPITE
WIND GUSTS UP TO 20 KNOTS. HAVE CONTINUED SCA.

APPROACHING SURFACE LOW PRESSURE FROM THE MID-ATLANTIC TONIGHT WILL
HELP INCREASE AN EASTERLY LLJ OVER THE WATER TOMORROW. THIS WILL
BUILD THE SEAS BETWEEN 5-8 FT. COULD SEE WIND GUSTS BETWEEN 20-30
KTS AS THE FRONT PASSES. SCA HAS BEEN EXPANDED ACCORDINGLY.

OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...MODERATE CONFIDENCE

WEDNESDAY-THURSDAY... SOUTH WINDS WITH FREQUENT GUSTS 35 TO 40
KNOTS BY WEDNESDAY AFTERNOON AND CONTINUING THROUGH THE NIGHT.
WINDS SHIFT WEST THURSDAY MORNING WITH SIMILAR SPEEDS THROUGH THE
AFTERNOON. SEAS WILL BUILD TO 7 TO 12 FEET ON THE EXPOSED WATERS
BY WEDNESDAY NIGHT AND THURSDAY. A GALE WARNING MAY BE NEEDED.

FRIDAY...WINDS DIMINISHING TO 25 KNOTS FRIDAY MORNING AND BELOW 25
KNOTS BY AFTERNOON.  SEAS LINGERING AT 5 TO 7 FEET ON THE EXPOSED
WATERS. A SMALL CRAFT ADVISORY MAY BE NEEDED.

&&

.TIDES/COASTAL FLOODING...
HIGH ASTRONOMICAL TIDES WILL OCCUR TUESDAY THROUGH THURSDAY.

TUESDAY...HIGH TIDE AT BOSTON WILL BE 11.6 FT. WINDS WILL BE FROM
THE EAST...SO THERE WILL BE ONSHORE FLOW DURING THIS HIGH TIDE
ALLOWING FOR MINOR SPLASHOVER. IF WINDS INCREASE THEN COULD SEE
SOME POCKETS OF MINOR COASTAL FLOODING.

WEDNESDAY...WINDS SHIFT TO A MORE SOUTHEASTERLY FLOW DURING THE DAY
AND INCREASE QUICKLY AS AN APPROACHING SYSTEM BRINGS PRESSURE
FALLS OF 1 MB/HR. THE WEDNESDAY AFTERNOON HIGH TIDE IN BOSTON IS
11.7 FT AND STRONG SOUTHEASTERLY WINDS WILL BE JUST OFFSHORE.
RIGHT NOW BELIEVE MINOR COASTAL FLOODING IS POSSIBLE ALONG THE
EAST COAST.

WEDNESDAY EVENING...SOUTHERLY WINDS ARE EXPECTED AND ASTRONOMICAL
TIDES INCREASE ALONG THE SOUTH COAST. HIGH TIDE IN PROVIDENCE WILL
BE 5.2 FT. 925 MB LLJ STRENGTHENS TO 55-65 KTS WHICH COULD PUSH A
DECENT SURGE UP ALONG THE SOUTH COAST DURING THE TIME OF HIGH
TIDE. THINKING THAT MINOR COASTAL FLOODING COULD OCCUR BUT CANNOT
RULE OUT MODERATE ALONG THE SOUTH COAST...ESPECIALLY IF LLJ
CONTINUES TO STRENGTHEN.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO 7 AM EST
     TUESDAY FOR ANZ250.
     SMALL CRAFT ADVISORY FROM 10 PM THIS EVENING TO 7 AM EST
     TUESDAY FOR ANZ251-255.
     SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 7 AM EST
     TUESDAY FOR ANZ254.

&&

$$
SYNOPSIS...WTB/DUNTEN
NEAR TERM...DUNTEN
SHORT TERM...DUNTEN
LONG TERM...WTB
AVIATION...WTB/DUNTEN
MARINE...WTB/DUNTEN
TIDES/COASTAL FLOODING...



000
FXUS61 KBOX 220743
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
243 AM EST MON DEC 22 2014

.SYNOPSIS...
SCATTERED SNOW/RAIN SHOWERS WILL CONTINUE TODAY THANKS TO THE
ONSHORE FLOW. A WEAK LOW PRESSURE WILL MOVE ACROSS NEW ENGLAND
BRINGING A PERIOD OF PRECIPITATION VERY LATE MONDAY NIGHT AND
INTO TUESDAY. A MUCH STRONGER STORM PASSING WEST OF NEW ENGLAND
WILL BRING HEAVY RAINFALL...GUSTY WINDS AND COASTAL FLOODING
CONCERNS TO THE REGION WEDNESDAY AND WEDNESDAY NIGHT. DRY BUT VERY
WINDY CONDITIONS FOLLOW FOR CHRISTMAS DAY. HIGH PRESSURE BRINGS
DRY WEATHER FRIDAY. ANOTHER DEVELOPING SYSTEM MAY BRING RAIN AND
SNOW NEXT SUNDAY.

&&

.NEAR TERM /THROUGH TODAY/...

UPPER LEVEL RIDGE BUILDS AHEAD OF DIGGING MIDWEST TROUGH WITH
HIGH PRESSURE REMAINING ANCHORED OVER THE CANADIAN MARITIMES
THROUGH TONIGHT.

EASTERLY FLOW WILL CONTINUE ONSHORE ALLOWING FOR THE PROFILE TO
CONTINUE TO MOISTEN IN THE LOW LEVELS. IF THIS MOISTURE DEEPENS
ENOUGH THEN WE COULD SEE LIGHT SHOWERS DEVELOP ESP ACROSS THE MASS
EAST COASTLINE. OTHERWISE DRIZZLE MAY BE THE MAIN FACTOR AS THE
UPPER LEVELS ARE FAIRLY DRY. OVERALL TODAY WILL BE A COOL AND CLOUDY
DAY WITH HIGHS ONLY REACHING IN THE UPPER 30S TO LOW 40S AS CROSS
SECTIONS ARE VERY MOIST IN THE LOW LEVELS.

&&

.SHORT TERM /TONIGHT THROUGH 6 PM TUESDAY/...

TONIGHT INTO TOMORROW...

*LIGHT FREEZING RAIN IS POSSIBLE ACROSS THE INTERIOR NORTHWEST AND
  NORTHERN WORCESTER HILLS*

A WEAK AREA OF LOW PRESSURE DEVELOPS ALONG A WARM FRONT OFF THE MID
ATLANTIC...DRIFTING NORTHWARD TOWARD THE AREA. THIS LOW REMAINS WEAK
AS THE WARM FRONT MOVES SLOWLY NORTHWARD TONIGHT INTO TOMORROW.
DECENT WARM ADVECTION AHEAD OF THIS WAVE WITH SEVERAL HI-RES
GUIDANCE MODELS SHOWS A POTENTIAL FOR COLD AIR DAMMING ACROSS THE
INTERIOR INTO TUESDAY MORNING.  BIGGEST QUESTION WILL BE THE
MOISTURE POTENTIAL...IS THERE ENOUGH TO DEVELOP PRECIP ESP TONIGHT?
GUIDANCE DOES SHOW ENOUGH LIFT AHEAD OF APPROACHING SURFACE LOW PER
THE GFS/EC SO ANTICIPATE PRECIP TO DEVELOP AND OVERSPREAD ACROSS
SOUTHERN NEW ENGLAND. IF THIS PLAYS OUT WITH COLD AIR DAMMING AND
WARM AIR ADVECTION...THEN WE COULD SEE FREEZING RAIN/DRIZZLE ACROSS
THE INTERIOR NORTHWEST AND NORTHERN WORCESTER HILLS VERY LATE
TONIGHT INTO TUESDAY MORNING. A WINTER WEATHER ADVISORY MAY BE
NEEDED.

AS SURFACE LOW CONTINUES TO MOVE NORTHWARD...AND HIGH PRESSURE OVER
EASTERN CANADA...ANTICIPATE AN INCREASING LLJ. THIS SOUTHEASTERLY
JET WILL CONTINUE TO FEED MOISTURE INTO THE REGION AND WITH
SOUNDINGS SHOW A VERY SATURATED PROFILE COULD SEE NUMEROUS SHOWERS
WITH PERHAPS A FEW HEAVY DOWNPOURS. NOTICED GUIDANCE HAS
INCREASED THE QPF OVER THE PAST FEW DAYS. AS THE WEAK SURFACE LOW
MOVES NORTH OF SOUTHERN NEW ENGLAND...WARM FRONT WILL LIFT
NORTHWARD SO ALL PRECIP BY THE LATE MORNING WILL BE IN THE LIQUID
FORM.

WE COULD ALSO SEE SOME MINOR COASTAL FLOODING CONCERNS ON TUESDAY
WITH DUE EASTERLY FLOW INCREASING TO ABOUT 20 TO 25 MPH.  SEE BELOW
FOR MORE DETAILS.


&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
BIG PICTURE...

TUESDAY STARTS WITH UPPER RIDGES ON EACH COAST AND A DEEP UPPER
TROUGH/CLOSED LOW OVER THE PLAINS. BY WEDNESDAY THE CLOSED LOW
EJECTS NORTHEAST THROUGH LAKE SUPERIOR INTO CANADA. THIS SWEEPS THE
TROUGH AXIS EAST AND PASSES ACROSS NEW ENGLAND CHRISTMAS DAY.
ANOTHER SHORTWAVE MOVES ONSHORE IN THE PACIFIC NORTHWEST WEDNESDAY
AND PHASES WITH A SECOND DROPPING SOUTH FROM NORTHERN CANADA.  THIS
REESTABLISHES THE UPPER TROUGH OVER THE NORTHERN PLAINS/GREAT LAKES
SATURDAY.

CONTOUR HEIGHTS WILL BE ABOVE NORMAL MIDWEEK...TRENDING BELOW NORMAL
OVER THE WEEKEND AS THE SECOND UPPER TROUGH SHIFTS EAST. THIS POINTS
TO A COOLING TREND AFTER CHRISTMAS.

THE GFS AND ECMWF ARE SIMILAR IN HANDLING THE HOLIDAY STORM. THERE
ARE DIFFERENCES BETWEEN THE MODELS IN HANDLING THE SUNDAY SYSTEM. WE
USED A BLEND MOST OF THE LONG TERM PERIOD...BUT MANUALLY ADJUSTED
POPS FOR SUNDAY WITH LOW CONFIDENCE IN MODEL VALUES.

THE DAILIES...

TUESDAY... HIGH PRESSURE OVER THE MARITIMES WITH RIDGING DOWN THE
ATLANTIC COAST. COASTAL LOW PRESSURE WAVE DEVELOPS ALONG STALLED
WARM FRONT AND MOVES NORTH.  AS THE COASTAL LOW MOVES NORTH IT WILL
RUN UP AGAINST THE MARITIME HIGH. THIS WILL INCREASE THE LOW LEVEL
PRESSURE GRADIENT AND INCREASE THE LOW LEVEL SOUTHEAST WINDS.
RESULT...A SOUTHEAST LOW LEVEL JET RUNS OVER THE RIDGING ALONG THE
COASTAL PLAIN INDUCING LOW LEVEL LIFT. THE MOIST LAYER EXPANDS ABOVE
800 MB...NOT DEEP BUT DEEP ENOUGH FOR THE LIFT TO GENERATE LIGHT
PCPN. PTYPE WILL BE RAIN MOST PLACES...BUT THERE COULD BE SPOTS OF
LIGHT FREEZING RAIN IN NORTHWEST MASSACHUSETTS. WE WILL MAINTAIN
CHANCE POPS BUT INCREASE TO AROUND 50 PCT...THE HIGH END OF THE
CHANCE RANGE.

LOW LEVEL SOUTH JET MOVES UP THE COAST TUESDAY NIGHT REACHING THE
COOLER AIR OVER NEW ENGLAND AFTER MIDNIGHT AND BEFORE SUNRISE. THIS
WILL GENERATE ADDITIONAL LIFT AS WELL AS INCREASING AND DEEPENING
MOISTURE. THIS SUGGESTS INCREASING POPS OVERNIGHT.  TEMPERATURES
SHOULD REMAIN ABOVE FREEZING SO PTYPE SHOULD BE RAIN.

WEDNESDAY-THURSDAY... SOUTH 40-50 KNOT LOW LEVEL JET MOVES OVER NEW
ENGLAND WEDNESDAY GENERATING STRONG LIFT AND TRANSPORTING HIGH
VALUES OF PRECIPITABLE WATER INTO THAT LIFT. THE MOISTURE VALUES ARE
MORE THAN 3 STD DEVIATIONS ABOVE NORMAL FOR DECEMBER...AND ACTUALLY
NEAR THE MAXIMUM PREVIOUSLY OBSERVED VALUE. THIS SUGGESTS RAIN WITH
SOME HEAVY DOWNPOURS. COLD FRONT APPROACHES LATE WEDNESDAY NIGHT AND
CROSSES SOUTHERN NEW ENGLAND CHRISTMAS MORNING. THE FRONT WILL HAVE
DYNAMIC SUPPORT FROM A 140-150 KNOT UPPER JET. THE FOREWARD PROGRESS
OF THE FRONT WILL SLOW BECAUSE MOST OF THE MOTION IN THE UPPER JET
WILL BE PARALLEL TO THE FRONT. THIS WILL MEAN CONTINUED RAIN/HEAVY
RAIN THROUGH THE NIGHT INTO THURSDAY MORNING.

THE OBVIOUS CONCERN FOR THIS PERIOD WILL BE FLOODING FROM HEAVY
RAINFALL. RAIN AMOUNTS OF 2 TO 3 INCHES ARE EXPECTED. THIS SHOULD BE
SUFFICIENT FOR AT LEAST URBAN AND POOR DRAINAGE FLOODING. A FLOOD
WATCH MAY BE NEEDED.

A SECOND CONCERN WILL BE WIND. THE LOW LEVEL JET WEDNESDAY WILL BE
SOUTH 40-50 KNOTS...AND INCREASE TO 55-65 KNOTS WEDNESDAY NIGHT.
CONVENTIONAL MIXING WILL NOT BE DEEP...BUT HEAVY DOWNPOURS COULD
CREATE A MOIST ADIABATIC CHANNEL THAT BRINGS DOWN SOME STRONGER WIND
GUSTS. MODEL GRIDS ARE RATHER LIGHT ON WIND GUSTS...15 TO 30 KNOTS.
WE WILL MANUALLY ADJUST THESE VALUES UP TO 25-35 KNOTS OVER LAND AND
A LITTLE STRONGER OVER WATER.

A THIRD CONCERN WILL BE COASTAL FLOODING. MORE DETAILS ON THIS IN
THE TIDE/COASTAL FLOOD SECTION.

WINDS SHIFT TO WEST BEHIND THE FRONT ON CHRISTMAS DAY. THIS WILL
BRING DRIER AIR AND SO END THE RAINFALL. COLD ADVECTION WILL PROMOTE
MIXING TO NEAR 850 MB IN THE AFTERNOON AND TAP 25-35 KNOT WIND
GUSTS...POSSIBLY 40 KNOT GUSTS. A WIND ADVISORY MAY BE NEEDED FOR
THESE WEST WINDS THURSDAY.

FRIDAY THROUGH SUNDAY.... HIGH PRESSURE MOVES OVER THE REGION FRIDAY
BRINGING DRY WEATHER.  SHORTWAVE MOVING THROUGH THE GREAT LAKES
SWINGS A COLD FRONT THROUGH NEW ENGLAND SATURDAY. THE SURFACE
REFLECTION OF THE SHORTWAVE MOVES UP THE ST LAWRENCE VALLEY AND JET
SUPPORT WILL MOSTLY BE NORTH OF THE BORDER...SO PCPN WILL BE
LIMITED. QUESTION FOR SUNDAY WILL BE WHETHER A WAVE FORMS ON THE
DEPARTING COLD FRONT...IF SO IT MIGHT BRING PCPN TO NEW ENGLAND.
THE ECMWF THINKS SO BUT THE GFS DOES NOT. WE BROUGHT IN A CHANCE
OF RAIN AND SNOW SHOWERS.

&&

.AVIATION /08Z MONDAY THROUGH FRIDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH TUESDAY/...

TODAY...HIGH CONFIDENCE. DRIZZLE OR A FEW FLURRIES POSSIBLE
ACROSS EAST MASS TERMINALS. OTHERWISE ANY VFR CIGS WILL DROP TO
MVFR CONDITIONS THROUGHOUT THE DAY.

TONIGHT...MODERATE CONFIDENCE. MAINLY MVFR CONDITIONS CONTINUE IN
SCATTERED LIGHT SNOW SHOWERS. LIGHT FZRA POSSIBLE LATE MONDAY NIGHT
ACROSS NW MASSACHUSETTS.

TUESDAY...MODERATE CONFIDENCE. MVFR CONDITIONS MAY DROP TO IFR
WITHIN AND HEAVY RAIN FALL. VSBYS WILL BE REDUCED TO 5SM OR LESS
AS WELL.

KBOS TERMINAL...MODERATE CONFIDENCE. COULD SEE DRIZZLE LATER TODAY.

KBDL TERMINAL...MODERATE CONFIDENCE.

OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...MODERATE CONFIDENCE

LATE TUESDAY NIGHT-WEDNESDAY-THURSDAY... CONDITIONS LOWERING TO
IFR/LIFR IN RAIN/HEAVY RAIN. SOUTHEAST WINDS GUSTING 25 TO 35
KNOTS WEDNESDAY AND SOUTH WINDS SIMILAR SPEEDS WEDNESDAY
NIGHT...EXCEPT 30 TO 40 KNOTS CAPE COD AND ISLANDS. WINDS AT 2000
FEET MAY REACH 55 TO 65 KNOTS BY WEDNESDAY NIGHT CREATING LOW
LEVEL WIND SHEAR. ISOLATED THUNDERSTORMS WEDNESDAY AFTERNOON AND
NIGHT. COLD FRONT SWINGS THROUGH ON THURSDAY MORNING BRINGING A
WIND SHIFT TO WEST WITH GUSTS 30-40 KNOTS. CONDITIONS IMPROVE TO
VFR AFTER THE WIND SHIFT.

FRIDAY...VFR.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH TUESDAY/...MODERATE TO HIGH CONFIDENCE.

HIGH PRESSURE ACROSS QUEBEC AND THE MARITIMES WILL RESULT IN
PERSISTENT NORTHEASTERLY TO EASTERLY WINDS ACROSS THE WATERS THROUGH
TODAY. THIS WILL BUILD SEAS TO 5FT ON THE EASTERN WATERS DESPITE
WIND GUSTS UP TO 20 KNOTS. HAVE CONTINUED SCA.

APPROACHING SURFACE LOW PRESSURE FROM THE MID-ATLANTIC TONIGHT WILL
HELP INCREASE AN EASTERLY LLJ OVER THE WATER TOMORROW. THIS WILL
BUILD THE SEAS BETWEEN 5-8 FT. COULD SEE WIND GUSTS BETWEEN 20-30
KTS AS THE FRONT PASSES. SCA HAS BEEN EXPANDED ACCORDINGLY.

OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...MODERATE CONFIDENCE

WEDNESDAY-THURSDAY... SOUTH WINDS WITH FREQUENT GUSTS 35 TO 40
KNOTS BY WEDNESDAY AFTERNOON AND CONTINUING THROUGH THE NIGHT.
WINDS SHIFT WEST THURSDAY MORNING WITH SIMILAR SPEEDS THROUGH THE
AFTERNOON. SEAS WILL BUILD TO 7 TO 12 FEET ON THE EXPOSED WATERS
BY WEDNESDAY NIGHT AND THURSDAY. A GALE WARNING MAY BE NEEDED.

FRIDAY...WINDS DIMINISHING TO 25 KNOTS FRIDAY MORNING AND BELOW 25
KNOTS BY AFTERNOON.  SEAS LINGERING AT 5 TO 7 FEET ON THE EXPOSED
WATERS. A SMALL CRAFT ADVISORY MAY BE NEEDED.

&&

.TIDES/COASTAL FLOODING...
HIGH ASTRONOMICAL TIDES WILL OCCUR TUESDAY THROUGH THURSDAY.

TUESDAY...HIGH TIDE AT BOSTON WILL BE 11.6 FT. WINDS WILL BE FROM
THE EAST...SO THERE WILL BE ONSHORE FLOW DURING THIS HIGH TIDE
ALLOWING FOR MINOR SPLASHOVER. IF WINDS INCREASE THEN COULD SEE
SOME POCKETS OF MINOR COASTAL FLOODING.

WEDNESDAY...WINDS SHIFT TO A MORE SOUTHEASTERLY FLOW DURING THE DAY
AND INCREASE QUICKLY AS AN APPROACHING SYSTEM BRINGS PRESSURE
FALLS OF 1 MB/HR. THE WEDNESDAY AFTERNOON HIGH TIDE IN BOSTON IS
11.7 FT AND STRONG SOUTHEASTERLY WINDS WILL BE JUST OFFSHORE.
RIGHT NOW BELIEVE MINOR COASTAL FLOODING IS POSSIBLE ALONG THE
EAST COAST.

WEDNESDAY EVENING...SOUTHERLY WINDS ARE EXPECTED AND ASTRONOMICAL
TIDES INCREASE ALONG THE SOUTH COAST. HIGH TIDE IN PROVIDENCE WILL
BE 5.2 FT. 925 MB LLJ STRENGTHENS TO 55-65 KTS WHICH COULD PUSH A
DECENT SURGE UP ALONG THE SOUTH COAST DURING THE TIME OF HIGH
TIDE. THINKING THAT MINOR COASTAL FLOODING COULD OCCUR BUT CANNOT
RULE OUT MODERATE ALONG THE SOUTH COAST...ESPECIALLY IF LLJ
CONTINUES TO STRENGTHEN.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO 7 AM EST
     TUESDAY FOR ANZ250.
     SMALL CRAFT ADVISORY FROM 10 PM THIS EVENING TO 7 AM EST
     TUESDAY FOR ANZ251-255.
     SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 7 AM EST
     TUESDAY FOR ANZ254.

&&

$$
SYNOPSIS...WTB/DUNTEN
NEAR TERM...DUNTEN
SHORT TERM...DUNTEN
LONG TERM...WTB
AVIATION...WTB/DUNTEN
MARINE...WTB/DUNTEN
TIDES/COASTAL FLOODING...



000
FXUS61 KBOX 220743
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
243 AM EST MON DEC 22 2014

.SYNOPSIS...
SCATTERED SNOW/RAIN SHOWERS WILL CONTINUE TODAY THANKS TO THE
ONSHORE FLOW. A WEAK LOW PRESSURE WILL MOVE ACROSS NEW ENGLAND
BRINGING A PERIOD OF PRECIPITATION VERY LATE MONDAY NIGHT AND
INTO TUESDAY. A MUCH STRONGER STORM PASSING WEST OF NEW ENGLAND
WILL BRING HEAVY RAINFALL...GUSTY WINDS AND COASTAL FLOODING
CONCERNS TO THE REGION WEDNESDAY AND WEDNESDAY NIGHT. DRY BUT VERY
WINDY CONDITIONS FOLLOW FOR CHRISTMAS DAY. HIGH PRESSURE BRINGS
DRY WEATHER FRIDAY. ANOTHER DEVELOPING SYSTEM MAY BRING RAIN AND
SNOW NEXT SUNDAY.

&&

.NEAR TERM /THROUGH TODAY/...

UPPER LEVEL RIDGE BUILDS AHEAD OF DIGGING MIDWEST TROUGH WITH
HIGH PRESSURE REMAINING ANCHORED OVER THE CANADIAN MARITIMES
THROUGH TONIGHT.

EASTERLY FLOW WILL CONTINUE ONSHORE ALLOWING FOR THE PROFILE TO
CONTINUE TO MOISTEN IN THE LOW LEVELS. IF THIS MOISTURE DEEPENS
ENOUGH THEN WE COULD SEE LIGHT SHOWERS DEVELOP ESP ACROSS THE MASS
EAST COASTLINE. OTHERWISE DRIZZLE MAY BE THE MAIN FACTOR AS THE
UPPER LEVELS ARE FAIRLY DRY. OVERALL TODAY WILL BE A COOL AND CLOUDY
DAY WITH HIGHS ONLY REACHING IN THE UPPER 30S TO LOW 40S AS CROSS
SECTIONS ARE VERY MOIST IN THE LOW LEVELS.

&&

.SHORT TERM /TONIGHT THROUGH 6 PM TUESDAY/...

TONIGHT INTO TOMORROW...

*LIGHT FREEZING RAIN IS POSSIBLE ACROSS THE INTERIOR NORTHWEST AND
  NORTHERN WORCESTER HILLS*

A WEAK AREA OF LOW PRESSURE DEVELOPS ALONG A WARM FRONT OFF THE MID
ATLANTIC...DRIFTING NORTHWARD TOWARD THE AREA. THIS LOW REMAINS WEAK
AS THE WARM FRONT MOVES SLOWLY NORTHWARD TONIGHT INTO TOMORROW.
DECENT WARM ADVECTION AHEAD OF THIS WAVE WITH SEVERAL HI-RES
GUIDANCE MODELS SHOWS A POTENTIAL FOR COLD AIR DAMMING ACROSS THE
INTERIOR INTO TUESDAY MORNING.  BIGGEST QUESTION WILL BE THE
MOISTURE POTENTIAL...IS THERE ENOUGH TO DEVELOP PRECIP ESP TONIGHT?
GUIDANCE DOES SHOW ENOUGH LIFT AHEAD OF APPROACHING SURFACE LOW PER
THE GFS/EC SO ANTICIPATE PRECIP TO DEVELOP AND OVERSPREAD ACROSS
SOUTHERN NEW ENGLAND. IF THIS PLAYS OUT WITH COLD AIR DAMMING AND
WARM AIR ADVECTION...THEN WE COULD SEE FREEZING RAIN/DRIZZLE ACROSS
THE INTERIOR NORTHWEST AND NORTHERN WORCESTER HILLS VERY LATE
TONIGHT INTO TUESDAY MORNING. A WINTER WEATHER ADVISORY MAY BE
NEEDED.

AS SURFACE LOW CONTINUES TO MOVE NORTHWARD...AND HIGH PRESSURE OVER
EASTERN CANADA...ANTICIPATE AN INCREASING LLJ. THIS SOUTHEASTERLY
JET WILL CONTINUE TO FEED MOISTURE INTO THE REGION AND WITH
SOUNDINGS SHOW A VERY SATURATED PROFILE COULD SEE NUMEROUS SHOWERS
WITH PERHAPS A FEW HEAVY DOWNPOURS. NOTICED GUIDANCE HAS
INCREASED THE QPF OVER THE PAST FEW DAYS. AS THE WEAK SURFACE LOW
MOVES NORTH OF SOUTHERN NEW ENGLAND...WARM FRONT WILL LIFT
NORTHWARD SO ALL PRECIP BY THE LATE MORNING WILL BE IN THE LIQUID
FORM.

WE COULD ALSO SEE SOME MINOR COASTAL FLOODING CONCERNS ON TUESDAY
WITH DUE EASTERLY FLOW INCREASING TO ABOUT 20 TO 25 MPH.  SEE BELOW
FOR MORE DETAILS.


&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
BIG PICTURE...

TUESDAY STARTS WITH UPPER RIDGES ON EACH COAST AND A DEEP UPPER
TROUGH/CLOSED LOW OVER THE PLAINS. BY WEDNESDAY THE CLOSED LOW
EJECTS NORTHEAST THROUGH LAKE SUPERIOR INTO CANADA. THIS SWEEPS THE
TROUGH AXIS EAST AND PASSES ACROSS NEW ENGLAND CHRISTMAS DAY.
ANOTHER SHORTWAVE MOVES ONSHORE IN THE PACIFIC NORTHWEST WEDNESDAY
AND PHASES WITH A SECOND DROPPING SOUTH FROM NORTHERN CANADA.  THIS
REESTABLISHES THE UPPER TROUGH OVER THE NORTHERN PLAINS/GREAT LAKES
SATURDAY.

CONTOUR HEIGHTS WILL BE ABOVE NORMAL MIDWEEK...TRENDING BELOW NORMAL
OVER THE WEEKEND AS THE SECOND UPPER TROUGH SHIFTS EAST. THIS POINTS
TO A COOLING TREND AFTER CHRISTMAS.

THE GFS AND ECMWF ARE SIMILAR IN HANDLING THE HOLIDAY STORM. THERE
ARE DIFFERENCES BETWEEN THE MODELS IN HANDLING THE SUNDAY SYSTEM. WE
USED A BLEND MOST OF THE LONG TERM PERIOD...BUT MANUALLY ADJUSTED
POPS FOR SUNDAY WITH LOW CONFIDENCE IN MODEL VALUES.

THE DAILIES...

TUESDAY... HIGH PRESSURE OVER THE MARITIMES WITH RIDGING DOWN THE
ATLANTIC COAST. COASTAL LOW PRESSURE WAVE DEVELOPS ALONG STALLED
WARM FRONT AND MOVES NORTH.  AS THE COASTAL LOW MOVES NORTH IT WILL
RUN UP AGAINST THE MARITIME HIGH. THIS WILL INCREASE THE LOW LEVEL
PRESSURE GRADIENT AND INCREASE THE LOW LEVEL SOUTHEAST WINDS.
RESULT...A SOUTHEAST LOW LEVEL JET RUNS OVER THE RIDGING ALONG THE
COASTAL PLAIN INDUCING LOW LEVEL LIFT. THE MOIST LAYER EXPANDS ABOVE
800 MB...NOT DEEP BUT DEEP ENOUGH FOR THE LIFT TO GENERATE LIGHT
PCPN. PTYPE WILL BE RAIN MOST PLACES...BUT THERE COULD BE SPOTS OF
LIGHT FREEZING RAIN IN NORTHWEST MASSACHUSETTS. WE WILL MAINTAIN
CHANCE POPS BUT INCREASE TO AROUND 50 PCT...THE HIGH END OF THE
CHANCE RANGE.

LOW LEVEL SOUTH JET MOVES UP THE COAST TUESDAY NIGHT REACHING THE
COOLER AIR OVER NEW ENGLAND AFTER MIDNIGHT AND BEFORE SUNRISE. THIS
WILL GENERATE ADDITIONAL LIFT AS WELL AS INCREASING AND DEEPENING
MOISTURE. THIS SUGGESTS INCREASING POPS OVERNIGHT.  TEMPERATURES
SHOULD REMAIN ABOVE FREEZING SO PTYPE SHOULD BE RAIN.

WEDNESDAY-THURSDAY... SOUTH 40-50 KNOT LOW LEVEL JET MOVES OVER NEW
ENGLAND WEDNESDAY GENERATING STRONG LIFT AND TRANSPORTING HIGH
VALUES OF PRECIPITABLE WATER INTO THAT LIFT. THE MOISTURE VALUES ARE
MORE THAN 3 STD DEVIATIONS ABOVE NORMAL FOR DECEMBER...AND ACTUALLY
NEAR THE MAXIMUM PREVIOUSLY OBSERVED VALUE. THIS SUGGESTS RAIN WITH
SOME HEAVY DOWNPOURS. COLD FRONT APPROACHES LATE WEDNESDAY NIGHT AND
CROSSES SOUTHERN NEW ENGLAND CHRISTMAS MORNING. THE FRONT WILL HAVE
DYNAMIC SUPPORT FROM A 140-150 KNOT UPPER JET. THE FOREWARD PROGRESS
OF THE FRONT WILL SLOW BECAUSE MOST OF THE MOTION IN THE UPPER JET
WILL BE PARALLEL TO THE FRONT. THIS WILL MEAN CONTINUED RAIN/HEAVY
RAIN THROUGH THE NIGHT INTO THURSDAY MORNING.

THE OBVIOUS CONCERN FOR THIS PERIOD WILL BE FLOODING FROM HEAVY
RAINFALL. RAIN AMOUNTS OF 2 TO 3 INCHES ARE EXPECTED. THIS SHOULD BE
SUFFICIENT FOR AT LEAST URBAN AND POOR DRAINAGE FLOODING. A FLOOD
WATCH MAY BE NEEDED.

A SECOND CONCERN WILL BE WIND. THE LOW LEVEL JET WEDNESDAY WILL BE
SOUTH 40-50 KNOTS...AND INCREASE TO 55-65 KNOTS WEDNESDAY NIGHT.
CONVENTIONAL MIXING WILL NOT BE DEEP...BUT HEAVY DOWNPOURS COULD
CREATE A MOIST ADIABATIC CHANNEL THAT BRINGS DOWN SOME STRONGER WIND
GUSTS. MODEL GRIDS ARE RATHER LIGHT ON WIND GUSTS...15 TO 30 KNOTS.
WE WILL MANUALLY ADJUST THESE VALUES UP TO 25-35 KNOTS OVER LAND AND
A LITTLE STRONGER OVER WATER.

A THIRD CONCERN WILL BE COASTAL FLOODING. MORE DETAILS ON THIS IN
THE TIDE/COASTAL FLOOD SECTION.

WINDS SHIFT TO WEST BEHIND THE FRONT ON CHRISTMAS DAY. THIS WILL
BRING DRIER AIR AND SO END THE RAINFALL. COLD ADVECTION WILL PROMOTE
MIXING TO NEAR 850 MB IN THE AFTERNOON AND TAP 25-35 KNOT WIND
GUSTS...POSSIBLY 40 KNOT GUSTS. A WIND ADVISORY MAY BE NEEDED FOR
THESE WEST WINDS THURSDAY.

FRIDAY THROUGH SUNDAY.... HIGH PRESSURE MOVES OVER THE REGION FRIDAY
BRINGING DRY WEATHER.  SHORTWAVE MOVING THROUGH THE GREAT LAKES
SWINGS A COLD FRONT THROUGH NEW ENGLAND SATURDAY. THE SURFACE
REFLECTION OF THE SHORTWAVE MOVES UP THE ST LAWRENCE VALLEY AND JET
SUPPORT WILL MOSTLY BE NORTH OF THE BORDER...SO PCPN WILL BE
LIMITED. QUESTION FOR SUNDAY WILL BE WHETHER A WAVE FORMS ON THE
DEPARTING COLD FRONT...IF SO IT MIGHT BRING PCPN TO NEW ENGLAND.
THE ECMWF THINKS SO BUT THE GFS DOES NOT. WE BROUGHT IN A CHANCE
OF RAIN AND SNOW SHOWERS.

&&

.AVIATION /08Z MONDAY THROUGH FRIDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH TUESDAY/...

TODAY...HIGH CONFIDENCE. DRIZZLE OR A FEW FLURRIES POSSIBLE
ACROSS EAST MASS TERMINALS. OTHERWISE ANY VFR CIGS WILL DROP TO
MVFR CONDITIONS THROUGHOUT THE DAY.

TONIGHT...MODERATE CONFIDENCE. MAINLY MVFR CONDITIONS CONTINUE IN
SCATTERED LIGHT SNOW SHOWERS. LIGHT FZRA POSSIBLE LATE MONDAY NIGHT
ACROSS NW MASSACHUSETTS.

TUESDAY...MODERATE CONFIDENCE. MVFR CONDITIONS MAY DROP TO IFR
WITHIN AND HEAVY RAIN FALL. VSBYS WILL BE REDUCED TO 5SM OR LESS
AS WELL.

KBOS TERMINAL...MODERATE CONFIDENCE. COULD SEE DRIZZLE LATER TODAY.

KBDL TERMINAL...MODERATE CONFIDENCE.

OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...MODERATE CONFIDENCE

LATE TUESDAY NIGHT-WEDNESDAY-THURSDAY... CONDITIONS LOWERING TO
IFR/LIFR IN RAIN/HEAVY RAIN. SOUTHEAST WINDS GUSTING 25 TO 35
KNOTS WEDNESDAY AND SOUTH WINDS SIMILAR SPEEDS WEDNESDAY
NIGHT...EXCEPT 30 TO 40 KNOTS CAPE COD AND ISLANDS. WINDS AT 2000
FEET MAY REACH 55 TO 65 KNOTS BY WEDNESDAY NIGHT CREATING LOW
LEVEL WIND SHEAR. ISOLATED THUNDERSTORMS WEDNESDAY AFTERNOON AND
NIGHT. COLD FRONT SWINGS THROUGH ON THURSDAY MORNING BRINGING A
WIND SHIFT TO WEST WITH GUSTS 30-40 KNOTS. CONDITIONS IMPROVE TO
VFR AFTER THE WIND SHIFT.

FRIDAY...VFR.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH TUESDAY/...MODERATE TO HIGH CONFIDENCE.

HIGH PRESSURE ACROSS QUEBEC AND THE MARITIMES WILL RESULT IN
PERSISTENT NORTHEASTERLY TO EASTERLY WINDS ACROSS THE WATERS THROUGH
TODAY. THIS WILL BUILD SEAS TO 5FT ON THE EASTERN WATERS DESPITE
WIND GUSTS UP TO 20 KNOTS. HAVE CONTINUED SCA.

APPROACHING SURFACE LOW PRESSURE FROM THE MID-ATLANTIC TONIGHT WILL
HELP INCREASE AN EASTERLY LLJ OVER THE WATER TOMORROW. THIS WILL
BUILD THE SEAS BETWEEN 5-8 FT. COULD SEE WIND GUSTS BETWEEN 20-30
KTS AS THE FRONT PASSES. SCA HAS BEEN EXPANDED ACCORDINGLY.

OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...MODERATE CONFIDENCE

WEDNESDAY-THURSDAY... SOUTH WINDS WITH FREQUENT GUSTS 35 TO 40
KNOTS BY WEDNESDAY AFTERNOON AND CONTINUING THROUGH THE NIGHT.
WINDS SHIFT WEST THURSDAY MORNING WITH SIMILAR SPEEDS THROUGH THE
AFTERNOON. SEAS WILL BUILD TO 7 TO 12 FEET ON THE EXPOSED WATERS
BY WEDNESDAY NIGHT AND THURSDAY. A GALE WARNING MAY BE NEEDED.

FRIDAY...WINDS DIMINISHING TO 25 KNOTS FRIDAY MORNING AND BELOW 25
KNOTS BY AFTERNOON.  SEAS LINGERING AT 5 TO 7 FEET ON THE EXPOSED
WATERS. A SMALL CRAFT ADVISORY MAY BE NEEDED.

&&

.TIDES/COASTAL FLOODING...
HIGH ASTRONOMICAL TIDES WILL OCCUR TUESDAY THROUGH THURSDAY.

TUESDAY...HIGH TIDE AT BOSTON WILL BE 11.6 FT. WINDS WILL BE FROM
THE EAST...SO THERE WILL BE ONSHORE FLOW DURING THIS HIGH TIDE
ALLOWING FOR MINOR SPLASHOVER. IF WINDS INCREASE THEN COULD SEE
SOME POCKETS OF MINOR COASTAL FLOODING.

WEDNESDAY...WINDS SHIFT TO A MORE SOUTHEASTERLY FLOW DURING THE DAY
AND INCREASE QUICKLY AS AN APPROACHING SYSTEM BRINGS PRESSURE
FALLS OF 1 MB/HR. THE WEDNESDAY AFTERNOON HIGH TIDE IN BOSTON IS
11.7 FT AND STRONG SOUTHEASTERLY WINDS WILL BE JUST OFFSHORE.
RIGHT NOW BELIEVE MINOR COASTAL FLOODING IS POSSIBLE ALONG THE
EAST COAST.

WEDNESDAY EVENING...SOUTHERLY WINDS ARE EXPECTED AND ASTRONOMICAL
TIDES INCREASE ALONG THE SOUTH COAST. HIGH TIDE IN PROVIDENCE WILL
BE 5.2 FT. 925 MB LLJ STRENGTHENS TO 55-65 KTS WHICH COULD PUSH A
DECENT SURGE UP ALONG THE SOUTH COAST DURING THE TIME OF HIGH
TIDE. THINKING THAT MINOR COASTAL FLOODING COULD OCCUR BUT CANNOT
RULE OUT MODERATE ALONG THE SOUTH COAST...ESPECIALLY IF LLJ
CONTINUES TO STRENGTHEN.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO 7 AM EST
     TUESDAY FOR ANZ250.
     SMALL CRAFT ADVISORY FROM 10 PM THIS EVENING TO 7 AM EST
     TUESDAY FOR ANZ251-255.
     SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 7 AM EST
     TUESDAY FOR ANZ254.

&&

$$
SYNOPSIS...WTB/DUNTEN
NEAR TERM...DUNTEN
SHORT TERM...DUNTEN
LONG TERM...WTB
AVIATION...WTB/DUNTEN
MARINE...WTB/DUNTEN
TIDES/COASTAL FLOODING...



000
FXUS61 KGYX 220457
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
1157 PM EST SUN DEC 21 2014

.SYNOPSIS...
AN ONSHORE FLOW MAY TRIGGER SOME FLURRIES OR LIGHT SNOW MAINLY OVER
SOUTHERN REGIONS RIGHT THROUGH TUESDAY. A SIGNIFICANT LOW
PRESSURE SYSTEM SYSTEM WILL GRADUALLY ORGANIZE WEDNESDAY...BEFORE
MOVING OVER THE GREAT LAKES. THIS COULD BRING WINDY CONDITIONS AND
THE POTENTIAL FOR HEAVY RAIN AROUND CHRISTMAS EVE INTO EARLY
CHRISTMAS MORNING. ANOTHER LOW PRESSURE SYSTEM WILL PASS BY TO OUR
NORTHWEST LATE IN THE WEEK AND EARLY NEXT WEEKEND.

&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...

1155 PM...MINOR ESTF UPDATE TO REFLECT CURRENT MESONET IN 1ST
PERIOD GRIDS.

PREV DISC...
AREAS OF LIGHT SNOW WILL CONTINUE INTO THIS EVENING HOURS
ASSOCIATED WITH "OCEAN EFFECT" ONSHORE FLOW...AND ALSO DUE TO THE
PROXIMITY OF A WEAK MID LEVEL LOW. IN GENERAL...WILL BE LOWERING
POPS AS WE HEAD INTO THE LATE EVENING HOURS...WITH THE GREATEST
CHANCE OF A SNOW SHOWERS ALONG AND NEAR THE COASTLINE. THE BEACH
AREAS WILL NEED TO BE MONITORED HOWEVER...AS THERE IS SOME
INDICATION OF A WEAK NORLUN TROUGH OVER THE REGION.

&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/...
SCATTERED SNOW SHOWERS AND FLURRIES WILL CONTINUE RIGHT THROUGH
MONDAY NIGHT OVER SOUTHERN AREAS DUE TO A PERSISTENT NORTHEAST
FLOW OVER THE MOIST GULF OF MAINE. MESO MODELS WITHIN THE 12Z
MODEL SUITE CONTINUE TO HAVE A DIFFICULT TIME PICKING UP ON THIS
LOW LEVEL MOISTURE AND PRECIP. HAVE THEREFORE RAISED POPS ABOVE
ALL AVAILABLE GUIDANCE.

A COLD AIR DAMMING SIGNATURE WILL BE FORMING BY MONDAY NIGHT.
THEREFORE...THE PTYPE SHOULD BE ALL SNOW THROUGH THE SHORT TERM
PORTION OF THE FORECAST...BEFORE THE WARM AIR POURS INTO THE
REGION.

&&

.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
THE WEAK ONSHORE FLOW CONTINUES INTO TUESDAY WITH LOW LEVEL
MOISTURE DEEPEST ALONG THE COAST. ON TUESDAY THE WARMER ONSHORE
FLOW DEEPENS AS THE HIGH MOVES FURTHER OFFSHORE ALLOWING A
SOUTHEAST FLOW TO INCREASE...SO SCATTERED LIGHT INTERMITTENT
PRECIPITATION EXPECTED...MOSTLY IN THE FORM OF RAIN EXCEPT SOME
IN THE FORM OF LIGHT SNOW IN THE MOUNTAINS BEFORE CHANGING OVER TO
RAIN EVEN IN THOSE AREAS. THE MAIN EVENT WILL BE THE ONSET OF THE
HEAVIER PRECIPITATION LATE TUESDAY NIGHT AND ESPECIALLY CHRISTMAS
EVE WHERE THE RAIN WILL BECOME HEAVY AT TIMES AS A STRONG WARM
ADVECTION PATTERN DEVELOPS BEING ACCOMPANIED BY A STRONG LOW/MID
LEVEL JET. THE MAIN UPPER LOW PASSES WELL TO OUR WEST AS IT MOVES
THROUGH THE GREAT LAKES. QPF TOTALS FOR LATE TUESDAY INTO THURSDAY
COULD BE IN THE 2-4 INCH RANGE. DUE TO VERY WARM AIR THIS WILL BE
IN THE FORM OF RAIN EVEN IN THE MOUNTAINS. SOME FLOODING PROBLEMS
MAY ARISE IN THE HEADWATERS BY WEDNESDAY NIGHT OR THURSDAY DUE TO
THE COMBINATION OF SOME SNOWMELT AND THE HEAVY RAINS. ALL MODELS
AGREE ON MILD TEMPERATURES...USED A BLEND OF THE MODELS.

SYSTEM FINALLY EXITS TO THE NORTHEAST BY THURSDAY AFTERNOON AS A
DRY SLOT MOVES ACROSS THE AREA FOLLOWED BY A COLD FRONT WITH A
RETURN TO SEASONAL TEMPS FOR FRI.

ANOTHER SYSTEM WHICH WILL BE WEAKER WILL APPROACH FOR THE WEEKEND.
MODELS DIFFER IN RUN TO RUN CONTINUITY AND ALSO VARIANCES IN
TIMING, STRENGTH, AND POSITION OF THIS SYSTEM. FOR NOW WILL BROAD
BRUSH DUE TO ALL THE UNCERTAINTY AS WELL AS PTYPE.

&&

.AVIATION /06Z MONDAY THROUGH FRIDAY/...
SHORT TERM...MAINLY VFR THROUGH MONDAY NIGHT...HOWEVER THERE MAY
BE BRIEFLY MVFR CONDITIONS IN SCATTERED SNOW SHOWERS SOUTHERN
LOCATIONS.

LONG TERM...MVFR CONDS EXPECTED TUE AND THEN LOWERING TO IFR TUE
NIGHT AND LIFR CONDITIONS WED INTO THU. CONDITIONS IMPROVE BY LATE
THU TO VFR.

&&

.MARINE...
SHORT TERM...WINDS AND SEAS WILL REMAIN MOSTLY OUT OF THE
NORTHEAST THROUGH MONDAY NIGHT. WINDS AND SEAS WILL REMAIN BELOW
SCA CONDITIONS.

LONG TERM...STRONG LOW PRESSURE WILL MOVE WELL TO THE WEST AND
WILL CAUSE WINDS TO INCREASE TO GALES TUESDAY NIGHT THROUGH
WEDNESDAY WITH BORDERLINE STORM FORCE WIND GUSTS POSSIBLE
WEDNESDAY NIGHT. SEAS COULD BUILD IN EXCESS OF 15 FT OVER THE
OUTER WATERS BY WEDNESDAY NIGHT OR EARLY THURSDAY. GUIDANCE LOOKS
LOW ON BOTH WINDS AND SEAS WHICH IS TYPICAL FOR THESE TYPE OF
EVENTS.

&&

.HYDROLOGY...
MODELS CONTINUE TO BACK OFF ON RAINFALL TOTALS FOR
THE CHRISTMAS EVE/EARLY CHRISTMAS MORNING EVENT...BUT AREA STILL
IN THE 1 TO 3 INCH RANGE. HOPING THE SNOWPACK IN THE MOUNTAINS AND
FOOTHILLS WILL TAKE IN SOME OF THE 1 TO 2 INCH RAINFALL AMOUNTS IN
THAT AREA...BUT STILL EXPECTED RAPID RISES IN THE HEADWATERS. OVER
SOUTHERN LOCATIONS...2 TO 3 INCHES OF RAIN EXPECTED. IN ANY
CASE...FLOODING IS A DISTINCT POSSIBLY CHRISTMAS EVE AND CHRISTMAS
MORNING ASSOCIATED WITH THE HEAVY RAIN AND SNOWMELT.

&&

.TIDES/COASTAL FLOODING...
ASTRONOMICAL TIDES ARE AT THEIR PEAK FOR THE MONTH. THIS...IN
COMBINATION WITH STRONG SOUTHERLY DEVELOPING GALES (WITH POSSIBLE
STORM FORCE GUSTS) WILL LIKELY ALLOW FOR ABOUT A 1 FOOT STORM
SURGE. WITH BUILDING WAVES IN THE 15 FOOT RANGE...EXPECT A FEW
AREAS TO HAVE COASTAL FLOODING...SPLASH-OVER AND BEACH EROSION.

NART WAVE RUN-UP MATRICES ARE ALREADY PREDICTING THE POTENTIAL FOR
COASTAL FLOODING...OVERWASH AND EROSION ACROSS MOST LOCATIONS IN
MAINE AND NEW HAMPSHIRE BASED ON OUR CURRENT STORM SURGE AND WAVE
PREDICTIONS.

THE QUESTION IS HOWEVER...WHEN WILL THE PEAK WINDS AND SEAS
ARRIVE? RIGHT NOW IT IS TOO EARLY TO TELL IF THIS PERIOD OF
INCLEMENT WEATHER/OCEAN CONDITIONS WILL ARRIVE NEAR THE TIME OF
HIGH TIDE. THE MIDDAY TIDES ON CHRISTMAS EVE AND CHRISTMAS DAY ARE
THE HIGHEST AT 11 FEET...WHILE THE 1 AM CHRISTMAS MORNING HIGH
TIDE IS LOWER AT 10 FEET.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.

&&

$$
ES



000
FXUS61 KGYX 220457
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
1157 PM EST SUN DEC 21 2014

.SYNOPSIS...
AN ONSHORE FLOW MAY TRIGGER SOME FLURRIES OR LIGHT SNOW MAINLY OVER
SOUTHERN REGIONS RIGHT THROUGH TUESDAY. A SIGNIFICANT LOW
PRESSURE SYSTEM SYSTEM WILL GRADUALLY ORGANIZE WEDNESDAY...BEFORE
MOVING OVER THE GREAT LAKES. THIS COULD BRING WINDY CONDITIONS AND
THE POTENTIAL FOR HEAVY RAIN AROUND CHRISTMAS EVE INTO EARLY
CHRISTMAS MORNING. ANOTHER LOW PRESSURE SYSTEM WILL PASS BY TO OUR
NORTHWEST LATE IN THE WEEK AND EARLY NEXT WEEKEND.

&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...

1155 PM...MINOR ESTF UPDATE TO REFLECT CURRENT MESONET IN 1ST
PERIOD GRIDS.

PREV DISC...
AREAS OF LIGHT SNOW WILL CONTINUE INTO THIS EVENING HOURS
ASSOCIATED WITH "OCEAN EFFECT" ONSHORE FLOW...AND ALSO DUE TO THE
PROXIMITY OF A WEAK MID LEVEL LOW. IN GENERAL...WILL BE LOWERING
POPS AS WE HEAD INTO THE LATE EVENING HOURS...WITH THE GREATEST
CHANCE OF A SNOW SHOWERS ALONG AND NEAR THE COASTLINE. THE BEACH
AREAS WILL NEED TO BE MONITORED HOWEVER...AS THERE IS SOME
INDICATION OF A WEAK NORLUN TROUGH OVER THE REGION.

&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/...
SCATTERED SNOW SHOWERS AND FLURRIES WILL CONTINUE RIGHT THROUGH
MONDAY NIGHT OVER SOUTHERN AREAS DUE TO A PERSISTENT NORTHEAST
FLOW OVER THE MOIST GULF OF MAINE. MESO MODELS WITHIN THE 12Z
MODEL SUITE CONTINUE TO HAVE A DIFFICULT TIME PICKING UP ON THIS
LOW LEVEL MOISTURE AND PRECIP. HAVE THEREFORE RAISED POPS ABOVE
ALL AVAILABLE GUIDANCE.

A COLD AIR DAMMING SIGNATURE WILL BE FORMING BY MONDAY NIGHT.
THEREFORE...THE PTYPE SHOULD BE ALL SNOW THROUGH THE SHORT TERM
PORTION OF THE FORECAST...BEFORE THE WARM AIR POURS INTO THE
REGION.

&&

.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
THE WEAK ONSHORE FLOW CONTINUES INTO TUESDAY WITH LOW LEVEL
MOISTURE DEEPEST ALONG THE COAST. ON TUESDAY THE WARMER ONSHORE
FLOW DEEPENS AS THE HIGH MOVES FURTHER OFFSHORE ALLOWING A
SOUTHEAST FLOW TO INCREASE...SO SCATTERED LIGHT INTERMITTENT
PRECIPITATION EXPECTED...MOSTLY IN THE FORM OF RAIN EXCEPT SOME
IN THE FORM OF LIGHT SNOW IN THE MOUNTAINS BEFORE CHANGING OVER TO
RAIN EVEN IN THOSE AREAS. THE MAIN EVENT WILL BE THE ONSET OF THE
HEAVIER PRECIPITATION LATE TUESDAY NIGHT AND ESPECIALLY CHRISTMAS
EVE WHERE THE RAIN WILL BECOME HEAVY AT TIMES AS A STRONG WARM
ADVECTION PATTERN DEVELOPS BEING ACCOMPANIED BY A STRONG LOW/MID
LEVEL JET. THE MAIN UPPER LOW PASSES WELL TO OUR WEST AS IT MOVES
THROUGH THE GREAT LAKES. QPF TOTALS FOR LATE TUESDAY INTO THURSDAY
COULD BE IN THE 2-4 INCH RANGE. DUE TO VERY WARM AIR THIS WILL BE
IN THE FORM OF RAIN EVEN IN THE MOUNTAINS. SOME FLOODING PROBLEMS
MAY ARISE IN THE HEADWATERS BY WEDNESDAY NIGHT OR THURSDAY DUE TO
THE COMBINATION OF SOME SNOWMELT AND THE HEAVY RAINS. ALL MODELS
AGREE ON MILD TEMPERATURES...USED A BLEND OF THE MODELS.

SYSTEM FINALLY EXITS TO THE NORTHEAST BY THURSDAY AFTERNOON AS A
DRY SLOT MOVES ACROSS THE AREA FOLLOWED BY A COLD FRONT WITH A
RETURN TO SEASONAL TEMPS FOR FRI.

ANOTHER SYSTEM WHICH WILL BE WEAKER WILL APPROACH FOR THE WEEKEND.
MODELS DIFFER IN RUN TO RUN CONTINUITY AND ALSO VARIANCES IN
TIMING, STRENGTH, AND POSITION OF THIS SYSTEM. FOR NOW WILL BROAD
BRUSH DUE TO ALL THE UNCERTAINTY AS WELL AS PTYPE.

&&

.AVIATION /06Z MONDAY THROUGH FRIDAY/...
SHORT TERM...MAINLY VFR THROUGH MONDAY NIGHT...HOWEVER THERE MAY
BE BRIEFLY MVFR CONDITIONS IN SCATTERED SNOW SHOWERS SOUTHERN
LOCATIONS.

LONG TERM...MVFR CONDS EXPECTED TUE AND THEN LOWERING TO IFR TUE
NIGHT AND LIFR CONDITIONS WED INTO THU. CONDITIONS IMPROVE BY LATE
THU TO VFR.

&&

.MARINE...
SHORT TERM...WINDS AND SEAS WILL REMAIN MOSTLY OUT OF THE
NORTHEAST THROUGH MONDAY NIGHT. WINDS AND SEAS WILL REMAIN BELOW
SCA CONDITIONS.

LONG TERM...STRONG LOW PRESSURE WILL MOVE WELL TO THE WEST AND
WILL CAUSE WINDS TO INCREASE TO GALES TUESDAY NIGHT THROUGH
WEDNESDAY WITH BORDERLINE STORM FORCE WIND GUSTS POSSIBLE
WEDNESDAY NIGHT. SEAS COULD BUILD IN EXCESS OF 15 FT OVER THE
OUTER WATERS BY WEDNESDAY NIGHT OR EARLY THURSDAY. GUIDANCE LOOKS
LOW ON BOTH WINDS AND SEAS WHICH IS TYPICAL FOR THESE TYPE OF
EVENTS.

&&

.HYDROLOGY...
MODELS CONTINUE TO BACK OFF ON RAINFALL TOTALS FOR
THE CHRISTMAS EVE/EARLY CHRISTMAS MORNING EVENT...BUT AREA STILL
IN THE 1 TO 3 INCH RANGE. HOPING THE SNOWPACK IN THE MOUNTAINS AND
FOOTHILLS WILL TAKE IN SOME OF THE 1 TO 2 INCH RAINFALL AMOUNTS IN
THAT AREA...BUT STILL EXPECTED RAPID RISES IN THE HEADWATERS. OVER
SOUTHERN LOCATIONS...2 TO 3 INCHES OF RAIN EXPECTED. IN ANY
CASE...FLOODING IS A DISTINCT POSSIBLY CHRISTMAS EVE AND CHRISTMAS
MORNING ASSOCIATED WITH THE HEAVY RAIN AND SNOWMELT.

&&

.TIDES/COASTAL FLOODING...
ASTRONOMICAL TIDES ARE AT THEIR PEAK FOR THE MONTH. THIS...IN
COMBINATION WITH STRONG SOUTHERLY DEVELOPING GALES (WITH POSSIBLE
STORM FORCE GUSTS) WILL LIKELY ALLOW FOR ABOUT A 1 FOOT STORM
SURGE. WITH BUILDING WAVES IN THE 15 FOOT RANGE...EXPECT A FEW
AREAS TO HAVE COASTAL FLOODING...SPLASH-OVER AND BEACH EROSION.

NART WAVE RUN-UP MATRICES ARE ALREADY PREDICTING THE POTENTIAL FOR
COASTAL FLOODING...OVERWASH AND EROSION ACROSS MOST LOCATIONS IN
MAINE AND NEW HAMPSHIRE BASED ON OUR CURRENT STORM SURGE AND WAVE
PREDICTIONS.

THE QUESTION IS HOWEVER...WHEN WILL THE PEAK WINDS AND SEAS
ARRIVE? RIGHT NOW IT IS TOO EARLY TO TELL IF THIS PERIOD OF
INCLEMENT WEATHER/OCEAN CONDITIONS WILL ARRIVE NEAR THE TIME OF
HIGH TIDE. THE MIDDAY TIDES ON CHRISTMAS EVE AND CHRISTMAS DAY ARE
THE HIGHEST AT 11 FEET...WHILE THE 1 AM CHRISTMAS MORNING HIGH
TIDE IS LOWER AT 10 FEET.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.

&&

$$
ES




000
FXUS61 KBOX 220258
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
958 PM EST SUN DEC 21 2014

.SYNOPSIS...
SCATTERED SNOW/RAIN SHOWERS CONTINUE THROUGH MONDAY. WEAK LOW
PRESSURE WILL PASS SOUTH OF NEW ENGLAND BRINGING ANOTHER PERIOD OF
PRECIPITATION MONDAY NIGHT AND TUESDAY. A MUCH STRONGER STORM
PASSING WEST OF NEW ENGLAND WILL BRING HEAVY RAINFALL... GUSTY
WINDS AND COASTAL FLOODING CONCERNS TO THE REGION WEDNESDAY AND
WEDNESDAY NIGHT. DRY BUT VERY WINDY CONDITIONS FOLLOW FOR
CHRISTMAS DAY. HIGH PRESSURE BRINGS DRY WEATHER FRIDAY. ANOTHER
DEVELOPING SYSTEM MAY BRING RAIN AND SNOW NEXT SUNDAY.

&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...

1000 PM UPDATE...

LATEST RADAR IMAGERY SHOWS LIGHT RADAR ECHOES ACROSS PORTIONS OF
SOUTHERN NEW ENGLAND...ESP SOUTH OF THE PIKE. DUE TO MOIST ONSHORE
FLOW FOR THE REMINDER OF THE NIGHT BELIEVE FLURRIES/LIGHT SNOW
SHOWERS WILL CONTINUE. NOT MUCH ACCUMULATION IS ANTICIPATED.
TEMPERATURES AT OR NEAR FREEZING COMBINED WITH HIGHER DEWPOINTS
MAY LEAD TO A FEW SLICK SPOTS OVERNIGHT INTO TOMORROW MORNING.
DRIVERS ARE URGED TO USE CAUTION.

PREVIOUS DISCUSSION...
SHORTWAVE RIDGING BUILDS OVER SOUTHERN NEW ENGLAND OVERNIGHT. IN
ADDITION...HIGH PRESSURE IN QUEBEC BUILDS OVER THE REGION AS WELL.
THEREFORE...THERE WILL BE NO FOCUSING MECHANISM FOR PRECIP.
HOWEVER...ONSHORE FLOW AND DECENT MID LEVEL LAPSE RATES WILL ALLOW
FOR A FEW SCATTERED SNOW/RAIN SHOWERS ACROSS THE AREA OVERNIGHT.
EXPECT SNOW SHOWERS TO REMAIN ROUGHLY NORTH AND WEST OF A NEWPORT
TO TAUNTON TO SCITUATE LINE. ANY ADDITIONAL SNOWFALL WILL AMOUNT
TO A DUSTING TO ABOUT AN INCH. TEMPERATURES WILL FALL INTO THE MID
20S ACROSS THE NORTHWEST TO THE MID 30S ON THE CAPE AND ISLANDS.

&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/...
MONDAY...CLOUDY...DAMP...AND RAW CONDITIONS WILL CONTINUE THROUGH
THE DAY WITH CONTINUED ONSHORE FLOW AND SCATTERED SNOW/RAIN SHOWERS.

MONDAY NIGHT...WEAK LOW PRESSURE MOVING UP THE COAST TO JUST OFF THE
DELMARVA PENINSULA WILL PRODUCE WARM ADVECTION OVER SOUTHERN NEW
ENGLAND.  THIS IN TURN WILL LIKELY RESULT IN SOME PRECIPITATION
DEVELOPING OVERNIGHT.  HIGH PRESSURE MOVING INTO THE MARITIMES WILL
ALLOW FOR SOME COLD AIR DAMMING...PARTICULARLY INTO INTERIOR
SOUTHERN NEW ENGLAND.  THIS SCENARIO IS A GOOD SET UP FOR SOME
FREEZING RAIN ACROSS THE INTERIOR.  THE MAIN QUESTION IS HOW FAR
NORTH THE WARMER AIR GETS AS THIS WILL DETERMINE PTYPE.  FOR
NOW...WILL MAKE MENTION OF THE POTENTIAL FOR AN AREA OF FREEZING
RAIN IN THE HAZARDOUS WEATHER OUTLOOK. IF FREEZING RAIN LOOKS TO BE
MORE CERTAIN...WE WILL NEED TO ISSUE A WINTER WEATHER ADVISORY.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
BIG PICTURE...

TUESDAY STARTS WITH UPPER RIDGES ON EACH COAST AND A DEEP UPPER
TROUGH/CLOSED LOW OVER THE PLAINS. BY WEDNESDAY THE CLOSED LOW
EJECTS NORTHEAST THROUGH LAKE SUPERIOR INTO CANADA. THIS SWEEPS THE
TROUGH AXIS EAST AND PASSES ACROSS NEW ENGLAND CHRISTMAS DAY.
ANOTHER SHORTWAVE MOVES ONSHORE IN THE PACIFIC NORTHWEST WEDNESDAY
AND PHASES WITH A SECOND DROPPING SOUTH FROM NORTHERN CANADA.  THIS
REESTABLISHES THE UPPER TROUGH OVER THE NORTHERN PLAINS/GREAT LAKES
SATURDAY.

CONTOUR HEIGHTS WILL BE ABOVE NORMAL MIDWEEK...TRENDING BELOW NORMAL
OVER THE WEEKEND AS THE SECOND UPPER TROUGH SHIFTS EAST. THIS POINTS
TO A COOLING TREND AFTER CHRISTMAS.

THE GFS AND ECMWF ARE SIMILAR IN HANDLING THE HOLIDAY STORM. THERE
ARE DIFFERENCES BETWEEN THE MODELS IN HANDLING THE SUNDAY SYSTEM. WE
USED A BLEND MOST OF THE LONG TERM PERIOD...BUT MANUALLY ADJUSTED
POPS FOR SUNDAY WITH LOW CONFIDENCE IN MODEL VALUES.

THE DAILIES...

TUESDAY... HIGH PRESSURE OVER THE MARITIMES WITH RIDGING DOWN THE
ATLANTIC COAST. COASTAL LOW PRESSURE WAVE DEVELOPS ALONG STALLED
WARM FRONT AND MOVES NORTH.  AS THE COASTAL LOW MOVES NORTH IT WILL
RUN UP AGAINST THE MARITIME HIGH. THIS WILL INCREASE THE LOW LEVEL
PRESSURE GRADIENT AND INCREASE THE LOW LEVEL SOUTHEAST WINDS.
RESULT...A SOUTHEAST LOW LEVEL JET RUNS OVER THE RIDGING ALONG THE
COASTAL PLAIN INDUCING LOW LEVEL LIFT. THE MOIST LAYER EXPANDS ABOVE
800 MB...NOT DEEP BUT DEEP ENOUGH FOR THE LIFT TO GENERATE LIGHT
PCPN. PTYPE WILL BE RAIN MOST PLACES...BUT THERE COULD BE SPOTS OF
LIGHT FREEZING RAIN IN NORTHWEST MASSACHUSETTS. WE WILL MAINTAIN
CHANCE POPS BUT INCREASE TO AROUND 50 PCT...THE HIGH END OF THE
CHANCE RANGE.

LOW LEVEL SOUTH JET MOVES UP THE COAST TUESDAY NIGHT REACHING THE
COOLER AIR OVER NEW ENGLAND AFTER MIDNIGHT AND BEFORE SUNRISE. THIS
WILL GENERATE ADDITIONAL LIFT AS WELL AS INCREASING AND DEEPENING
MOISTURE. THIS SUGGESTS INCREASING POPS OVERNIGHT.  TEMPERATURES
SHOULD REMAIN ABOVE FREEZING SO PTYPE SHOULD BE RAIN.

WEDNESDAY-THURSDAY... SOUTH 40-50 KNOT LOW LEVEL JET MOVES OVER NEW
ENGLAND WEDNESDAY GENERATING STRONG LIFT AND TRANSPORTING HIGH
VALUES OF PRECIPITABLE WATER INTO THAT LIFT. THE MOISTURE VALUES ARE
MORE THAN 3 STD DEVIATIONS ABOVE NORMAL FOR DECEMBER...AND ACTUALLY
NEAR THE MAXIMUM PREVIOUSLY OBSERVED VALUE. THIS SUGGESTS RAIN WITH
SOME HEAVY DOWNPOURS. COLD FRONT APPROACHES LATE WEDNESDAY NIGHT AND
CROSSES SOUTHERN NEW ENGLAND CHRISTMAS MORNING. THE FRONT WILL HAVE
DYNAMIC SUPPORT FROM A 140-150 KNOT UPPER JET. THE FOREWARD PROGRESS
OF THE FRONT WILL SLOW BECAUSE MOST OF THE MOTION IN THE UPPER JET
WILL BE PARALLEL TO THE FRONT. THIS WILL MEAN CONTINUED RAIN/HEAVY
RAIN THROUGH THE NIGHT INTO THURSDAY MORNING.

THE OBVIOUS CONCERN FOR THIS PERIOD WILL BE FLOODING FROM HEAVY
RAINFALL. RAIN AMOUNTS OF 2 TO 3 INCHES ARE EXPECTED. THIS SHOULD BE
SUFFICIENT FOR AT LEAST URBAN AND POOR DRAINAGE FLOODING. A FLOOD
WATCH MAY BE NEEDED.

A SECOND CONCERN WILL BE WIND. THE LOW LEVEL JET WEDNESDAY WILL BE
SOUTH 40-50 KNOTS...AND INCREASE TO 55-65 KNOTS WEDNESDAY NIGHT.
CONVENTIONAL MIXING WILL NOT BE DEEP...BUT HEAVY DOWNPOURS COULD
CREATE A MOIST ADIABATIC CHANNEL THAT BRINGS DOWN SOME STRONGER WIND
GUSTS. MODEL GRIDS ARE RATHER LIGHT ON WIND GUSTS...15 TO 30 KNOTS.
WE WILL MANUALLY ADJUST THESE VALUES UP TO 25-35 KNOTS OVER LAND AND
A LITTLE STRONGER OVER WATER.

A THIRD CONCERN WILL BE COASTAL FLOODING. MORE DETAILS ON THIS IN
THE TIDE/COASTAL FLOOD SECTION.

WINDS SHIFT TO WEST BEHIND THE FRONT ON CHRISTMAS DAY. THIS WILL
BRING DRIER AIR AND SO END THE RAINFALL. COLD ADVECTION WILL PROMOTE
MIXING TO NEAR 850 MB IN THE AFTERNOON AND TAP 25-35 KNOT WIND
GUSTS...POSSIBLY 40 KNOT GUSTS. A WIND ADVISORY MAY BE NEEDED FOR
THESE WEST WINDS THURSDAY.

FRIDAY THROUGH SUNDAY.... HIGH PRESSURE MOVES OVER THE REGION FRIDAY
BRINGING DRY WEATHER.  SHORTWAVE MOVING THROUGH THE GREAT LAKES
SWINGS A COLD FRONT THROUGH NEW ENGLAND SATURDAY. THE SURFACE
REFLECTION OF THE SHORTWAVE MOVES UP THE ST LAWRENCE VALLEY AND JET
SUPPPORT WILL MOSTLY BE NORTH OF THE BORDER...SO PCPN WILL BE
LIMITED.  QUESTION FOR SUNDAY WILL BE WHETHER A WAVE FORMS ON THE
DEPARTING COLD FRONT...IF SO IT MIGHT BRING PCPN TO NEW ENGLAND. THE
ECMWF THINKS SO BUT THE GFS DOES NOT. WE BROUGHT IN A CHANCE OF RAIN
AND SNOW SHOWERS.

&&

.AVIATION /03Z MONDAY THROUGH FRIDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH MONDAY NIGHT/...

TONIGHT...MODERATE CONFIDENCE. MAINLY MVFR CONDITIONS THROUGH
TONIGHT. ONE EXCEPTION IS OVER BOSTON AND ESSEX COUNTY WHERE THE
1500 FOOT CEILING BROKE TO 6500 FEET AND MAY STAY LIKE THAT
THROUGH THE EARLY NIGHT. BUT WITH CONTINUED ONSHORE FLOW AND A FEW
RAIN/SNOW SHOWERS UPSTREAM IT IS POSSIBLE CIGS WILL DROP BACK TO
1500 FEET IN ANY SHOWERS. THE OVERALL MOIST FLOW SHOULD ALSO BRING
LEVELS BACK TO MVFR OVERNIGHT. SECOND EXCEPTION IS OVER CAPE COD AND
THE ISLANDS WHERE VFR CONDITIONS CONTINUE IN PLACE. BELIEVE THESE
CONDITIONS WILL ALSO DETERIORATE OVERNIGHT IN THE ONSHORE
NORTHEAST FLOW.

MONDAY AND MONDAY NIGHT...MODERATE CONFIDENCE. MAINLY MVFR
CONDITIONS CONTINUE IN SCATTERED LIGHT SNOW SHOWERS. LIGHT FZRA
POSSIBLE LATE MONDAY NIGHT ACROSS NW MASSACHUSETTS.

KBOS TERMINAL...MODERATE CONFIDENCE.

KBDL TERMINAL...MODERATE CONFIDENCE.

OUTLOOK...TUESDAY THROUGH FRIDAY...MODERATE CONFIDENCE

TUESDAY...MVFR CIGS AND VSBYS IN LIGHT RAIN.  EAST SOUTHEAST
WINDS...WITH FREQUENT GUSTS TO 25 KNOTS ON THE CAPE AND ISLANDS.

LATE TUESDAY NIGHT-WEDNESDAY-THURSDAY... CONDITIONS LOWERING TO
IFR/LIFR IN RAIN/HEAVY RAIN. SOUTHEAST WINDS GUSTING 25 TO 35 KNOTS
WEDNESDAY AND SOUTH WINDS SIMILAR SPEEDS WEDNESDAY NIGHT...EXCEPT 30
TO 40 KNOTS CAPE COD AND ISLANDS. WINDS AT 2000 FEET MAY REACH 55 TO
65 KNOTS BY WEDNESDAY NIGHT CREATING LOW LEVEL WIND SHEAR. ISOLATED
THUNDERSTORMS WEDNESDAY AFTERNOON AND NIGHT. COLD FRONT SWINGS
THROUGH ON THURSDAY MORNING BRINGING A WIND SHIFT TO WEST WITH GUSTS
30-40 KNOTS.  CONDITIONS IMPROVE TO VFR AFTER THE WIND SHIFT.

FRIDAY...VFR.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

HIGH PRESSURE ACROSS QUEBEC AND THE MARITIMES WILL RESULT IN
PERSISTENT NORTHEASTERLY TO EASTERLY WINDS ACROSS THE WATERS THROUGH
MONDAY.  THIS WILL RESULT IN BUILDING SEAS ON THE EASTERN WATERS
DESPITE WIND GUSTS UP TO 20 KNOTS.  SEAS BUILD TO AT LEAST 5 FEET ON
THE EASTERN WATERS BY MIDDAY MONDAY. A SMALL CRAFT ADVISORY
CONTINUES FOR THE EASTERN WATERS FOR THE PERIOD FROM MIDDAY
MONDAY THROUGH TUESDAY MORNING. WINDS INCREASE TO NEAR 25 KTS ON
THE SOUTHERN WATERS BY 12Z TUESDAY.

OUTLOOK...TUESDAY THROUGH FRIDAY...MODERATE CONFIDENCE

TUESDAY...EAST WIND GUSTING TO 25 KNOTS...BECOMING SOUTHEAST AT
NIGHT. SEAS 5 TO 7 FEET ON THE EXPOSED WATERS.  A SMALL CRAFT
ADVISORY WILL BE NEEDED.

WEDNESDAY-THURSDAY... SOUTH WINDS WITH FREQUENT GUSTS 35 TO 40 KNOTS
BY WEDNESDAY AFTERNOON AND CONTINUING THROUGH THE NIGHT. WINDS SHIFT
WEST THURSDAY MORNING WITH SIMILAR SPEEDS THROUGH THE AFTERNOON.
SEAS WILL BUILD TO 7 TO 12 FEET ON THE EXPOSED WATERS BY WEDNESDAY
NIGHT AND THURSDAY.  A GALE WARNING MAY BE NEEDED.

FRIDAY...WINDS DIMINISHING TO 25 KNOTS FRIDAY MORNING AND BELOW 25
KNOTS BY AFTERNOON.  SEAS LINGERING AT 5 TO 7 FEET ON THE EXPOSED
WATERS. A SMALL CRAFT ADVISORY MAY BE NEEDED.

&&

.TIDES/COASTAL FLOODING...
HIGH ASTRONOMICAL TIDES WILL OCCUR TUESDAY THROUGH THURSDAY.

TUESDAY...HIGH TIDE AT BOSTON WILL BE 11.6 FT. WINDS WILL BE FROM
THE EAST...SO THERE WILL BE ONSHORE FLOW DURING THIS HIGH TIDE
ALLOWING FOR MINOR SPLASHOVER. IF WINDS INCREASE THEN COULD SEE
SOME POCKETS OF MINOR COASTAL FLOODING.

WEDNESDAY...WINDS SHIFT TO A MORE SOUTHEASTERLY FLOW DURING THE DAY
AND INCREASE QUICKLY AS AN APPROACHING SYSTEM BRINGS PRESSURE
FALLS OF 1 MB/HR. THE WEDNESDAY AFTERNOON HIGH TIDE IN BOSTON IS
11.7 FT AND STRONG SOUTHEASTERLY WINDS WILL BE JUST OFFSHORE.
RIGHT NOW BELIEVE MINOR COASTAL FLOODING IS POSSIBLE ALONG THE
EAST COAST.

WEDNESDAY EVENING...SOUTHERLY WINDS ARE EXPECTED AND ASTRONOMICAL
TIDES INCREASE ALONG THE SOUTH COAST. HIGH TIDE IN PROVIDENCE WILL
BE 5.2 FT. 925 MB LLJ STRENGTHENS TO 55-65 KTS WHICH COULD PUSH A
DECENT SURGE UP ALONG THE SOUTH COAST DURING THE TIME OF HIGH
TIDE. THINKING THAT MINOR COASTAL FLOODING COULD OCCUR BUT CANNOT
RULE OUT MODERATE ALONG THE SOUTH COAST...ESPECIALLY IF LLJ
CONTINUES TO STRENGTHEN.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 4 PM MONDAY TO 7 AM EST TUESDAY FOR
     ANZ250.
     SMALL CRAFT ADVISORY FROM 10 PM MONDAY TO 7 AM EST TUESDAY FOR
     ANZ251-255.
     SMALL CRAFT ADVISORY FROM 1 PM MONDAY TO 7 AM EST TUESDAY FOR
     ANZ254.

&&

$$
SYNOPSIS...WTB/RLG
NEAR TERM...DUNTEN/RLG
SHORT TERM...RLG
LONG TERM...WTB
AVIATION...WTB/RLG
MARINE...WTB/RLG
TIDES/COASTAL FLOODING...



000
FXUS61 KBOX 220258
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
958 PM EST SUN DEC 21 2014

.SYNOPSIS...
SCATTERED SNOW/RAIN SHOWERS CONTINUE THROUGH MONDAY. WEAK LOW
PRESSURE WILL PASS SOUTH OF NEW ENGLAND BRINGING ANOTHER PERIOD OF
PRECIPITATION MONDAY NIGHT AND TUESDAY. A MUCH STRONGER STORM
PASSING WEST OF NEW ENGLAND WILL BRING HEAVY RAINFALL... GUSTY
WINDS AND COASTAL FLOODING CONCERNS TO THE REGION WEDNESDAY AND
WEDNESDAY NIGHT. DRY BUT VERY WINDY CONDITIONS FOLLOW FOR
CHRISTMAS DAY. HIGH PRESSURE BRINGS DRY WEATHER FRIDAY. ANOTHER
DEVELOPING SYSTEM MAY BRING RAIN AND SNOW NEXT SUNDAY.

&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...

1000 PM UPDATE...

LATEST RADAR IMAGERY SHOWS LIGHT RADAR ECHOES ACROSS PORTIONS OF
SOUTHERN NEW ENGLAND...ESP SOUTH OF THE PIKE. DUE TO MOIST ONSHORE
FLOW FOR THE REMINDER OF THE NIGHT BELIEVE FLURRIES/LIGHT SNOW
SHOWERS WILL CONTINUE. NOT MUCH ACCUMULATION IS ANTICIPATED.
TEMPERATURES AT OR NEAR FREEZING COMBINED WITH HIGHER DEWPOINTS
MAY LEAD TO A FEW SLICK SPOTS OVERNIGHT INTO TOMORROW MORNING.
DRIVERS ARE URGED TO USE CAUTION.

PREVIOUS DISCUSSION...
SHORTWAVE RIDGING BUILDS OVER SOUTHERN NEW ENGLAND OVERNIGHT. IN
ADDITION...HIGH PRESSURE IN QUEBEC BUILDS OVER THE REGION AS WELL.
THEREFORE...THERE WILL BE NO FOCUSING MECHANISM FOR PRECIP.
HOWEVER...ONSHORE FLOW AND DECENT MID LEVEL LAPSE RATES WILL ALLOW
FOR A FEW SCATTERED SNOW/RAIN SHOWERS ACROSS THE AREA OVERNIGHT.
EXPECT SNOW SHOWERS TO REMAIN ROUGHLY NORTH AND WEST OF A NEWPORT
TO TAUNTON TO SCITUATE LINE. ANY ADDITIONAL SNOWFALL WILL AMOUNT
TO A DUSTING TO ABOUT AN INCH. TEMPERATURES WILL FALL INTO THE MID
20S ACROSS THE NORTHWEST TO THE MID 30S ON THE CAPE AND ISLANDS.

&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/...
MONDAY...CLOUDY...DAMP...AND RAW CONDITIONS WILL CONTINUE THROUGH
THE DAY WITH CONTINUED ONSHORE FLOW AND SCATTERED SNOW/RAIN SHOWERS.

MONDAY NIGHT...WEAK LOW PRESSURE MOVING UP THE COAST TO JUST OFF THE
DELMARVA PENINSULA WILL PRODUCE WARM ADVECTION OVER SOUTHERN NEW
ENGLAND.  THIS IN TURN WILL LIKELY RESULT IN SOME PRECIPITATION
DEVELOPING OVERNIGHT.  HIGH PRESSURE MOVING INTO THE MARITIMES WILL
ALLOW FOR SOME COLD AIR DAMMING...PARTICULARLY INTO INTERIOR
SOUTHERN NEW ENGLAND.  THIS SCENARIO IS A GOOD SET UP FOR SOME
FREEZING RAIN ACROSS THE INTERIOR.  THE MAIN QUESTION IS HOW FAR
NORTH THE WARMER AIR GETS AS THIS WILL DETERMINE PTYPE.  FOR
NOW...WILL MAKE MENTION OF THE POTENTIAL FOR AN AREA OF FREEZING
RAIN IN THE HAZARDOUS WEATHER OUTLOOK. IF FREEZING RAIN LOOKS TO BE
MORE CERTAIN...WE WILL NEED TO ISSUE A WINTER WEATHER ADVISORY.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
BIG PICTURE...

TUESDAY STARTS WITH UPPER RIDGES ON EACH COAST AND A DEEP UPPER
TROUGH/CLOSED LOW OVER THE PLAINS. BY WEDNESDAY THE CLOSED LOW
EJECTS NORTHEAST THROUGH LAKE SUPERIOR INTO CANADA. THIS SWEEPS THE
TROUGH AXIS EAST AND PASSES ACROSS NEW ENGLAND CHRISTMAS DAY.
ANOTHER SHORTWAVE MOVES ONSHORE IN THE PACIFIC NORTHWEST WEDNESDAY
AND PHASES WITH A SECOND DROPPING SOUTH FROM NORTHERN CANADA.  THIS
REESTABLISHES THE UPPER TROUGH OVER THE NORTHERN PLAINS/GREAT LAKES
SATURDAY.

CONTOUR HEIGHTS WILL BE ABOVE NORMAL MIDWEEK...TRENDING BELOW NORMAL
OVER THE WEEKEND AS THE SECOND UPPER TROUGH SHIFTS EAST. THIS POINTS
TO A COOLING TREND AFTER CHRISTMAS.

THE GFS AND ECMWF ARE SIMILAR IN HANDLING THE HOLIDAY STORM. THERE
ARE DIFFERENCES BETWEEN THE MODELS IN HANDLING THE SUNDAY SYSTEM. WE
USED A BLEND MOST OF THE LONG TERM PERIOD...BUT MANUALLY ADJUSTED
POPS FOR SUNDAY WITH LOW CONFIDENCE IN MODEL VALUES.

THE DAILIES...

TUESDAY... HIGH PRESSURE OVER THE MARITIMES WITH RIDGING DOWN THE
ATLANTIC COAST. COASTAL LOW PRESSURE WAVE DEVELOPS ALONG STALLED
WARM FRONT AND MOVES NORTH.  AS THE COASTAL LOW MOVES NORTH IT WILL
RUN UP AGAINST THE MARITIME HIGH. THIS WILL INCREASE THE LOW LEVEL
PRESSURE GRADIENT AND INCREASE THE LOW LEVEL SOUTHEAST WINDS.
RESULT...A SOUTHEAST LOW LEVEL JET RUNS OVER THE RIDGING ALONG THE
COASTAL PLAIN INDUCING LOW LEVEL LIFT. THE MOIST LAYER EXPANDS ABOVE
800 MB...NOT DEEP BUT DEEP ENOUGH FOR THE LIFT TO GENERATE LIGHT
PCPN. PTYPE WILL BE RAIN MOST PLACES...BUT THERE COULD BE SPOTS OF
LIGHT FREEZING RAIN IN NORTHWEST MASSACHUSETTS. WE WILL MAINTAIN
CHANCE POPS BUT INCREASE TO AROUND 50 PCT...THE HIGH END OF THE
CHANCE RANGE.

LOW LEVEL SOUTH JET MOVES UP THE COAST TUESDAY NIGHT REACHING THE
COOLER AIR OVER NEW ENGLAND AFTER MIDNIGHT AND BEFORE SUNRISE. THIS
WILL GENERATE ADDITIONAL LIFT AS WELL AS INCREASING AND DEEPENING
MOISTURE. THIS SUGGESTS INCREASING POPS OVERNIGHT.  TEMPERATURES
SHOULD REMAIN ABOVE FREEZING SO PTYPE SHOULD BE RAIN.

WEDNESDAY-THURSDAY... SOUTH 40-50 KNOT LOW LEVEL JET MOVES OVER NEW
ENGLAND WEDNESDAY GENERATING STRONG LIFT AND TRANSPORTING HIGH
VALUES OF PRECIPITABLE WATER INTO THAT LIFT. THE MOISTURE VALUES ARE
MORE THAN 3 STD DEVIATIONS ABOVE NORMAL FOR DECEMBER...AND ACTUALLY
NEAR THE MAXIMUM PREVIOUSLY OBSERVED VALUE. THIS SUGGESTS RAIN WITH
SOME HEAVY DOWNPOURS. COLD FRONT APPROACHES LATE WEDNESDAY NIGHT AND
CROSSES SOUTHERN NEW ENGLAND CHRISTMAS MORNING. THE FRONT WILL HAVE
DYNAMIC SUPPORT FROM A 140-150 KNOT UPPER JET. THE FOREWARD PROGRESS
OF THE FRONT WILL SLOW BECAUSE MOST OF THE MOTION IN THE UPPER JET
WILL BE PARALLEL TO THE FRONT. THIS WILL MEAN CONTINUED RAIN/HEAVY
RAIN THROUGH THE NIGHT INTO THURSDAY MORNING.

THE OBVIOUS CONCERN FOR THIS PERIOD WILL BE FLOODING FROM HEAVY
RAINFALL. RAIN AMOUNTS OF 2 TO 3 INCHES ARE EXPECTED. THIS SHOULD BE
SUFFICIENT FOR AT LEAST URBAN AND POOR DRAINAGE FLOODING. A FLOOD
WATCH MAY BE NEEDED.

A SECOND CONCERN WILL BE WIND. THE LOW LEVEL JET WEDNESDAY WILL BE
SOUTH 40-50 KNOTS...AND INCREASE TO 55-65 KNOTS WEDNESDAY NIGHT.
CONVENTIONAL MIXING WILL NOT BE DEEP...BUT HEAVY DOWNPOURS COULD
CREATE A MOIST ADIABATIC CHANNEL THAT BRINGS DOWN SOME STRONGER WIND
GUSTS. MODEL GRIDS ARE RATHER LIGHT ON WIND GUSTS...15 TO 30 KNOTS.
WE WILL MANUALLY ADJUST THESE VALUES UP TO 25-35 KNOTS OVER LAND AND
A LITTLE STRONGER OVER WATER.

A THIRD CONCERN WILL BE COASTAL FLOODING. MORE DETAILS ON THIS IN
THE TIDE/COASTAL FLOOD SECTION.

WINDS SHIFT TO WEST BEHIND THE FRONT ON CHRISTMAS DAY. THIS WILL
BRING DRIER AIR AND SO END THE RAINFALL. COLD ADVECTION WILL PROMOTE
MIXING TO NEAR 850 MB IN THE AFTERNOON AND TAP 25-35 KNOT WIND
GUSTS...POSSIBLY 40 KNOT GUSTS. A WIND ADVISORY MAY BE NEEDED FOR
THESE WEST WINDS THURSDAY.

FRIDAY THROUGH SUNDAY.... HIGH PRESSURE MOVES OVER THE REGION FRIDAY
BRINGING DRY WEATHER.  SHORTWAVE MOVING THROUGH THE GREAT LAKES
SWINGS A COLD FRONT THROUGH NEW ENGLAND SATURDAY. THE SURFACE
REFLECTION OF THE SHORTWAVE MOVES UP THE ST LAWRENCE VALLEY AND JET
SUPPPORT WILL MOSTLY BE NORTH OF THE BORDER...SO PCPN WILL BE
LIMITED.  QUESTION FOR SUNDAY WILL BE WHETHER A WAVE FORMS ON THE
DEPARTING COLD FRONT...IF SO IT MIGHT BRING PCPN TO NEW ENGLAND. THE
ECMWF THINKS SO BUT THE GFS DOES NOT. WE BROUGHT IN A CHANCE OF RAIN
AND SNOW SHOWERS.

&&

.AVIATION /03Z MONDAY THROUGH FRIDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH MONDAY NIGHT/...

TONIGHT...MODERATE CONFIDENCE. MAINLY MVFR CONDITIONS THROUGH
TONIGHT. ONE EXCEPTION IS OVER BOSTON AND ESSEX COUNTY WHERE THE
1500 FOOT CEILING BROKE TO 6500 FEET AND MAY STAY LIKE THAT
THROUGH THE EARLY NIGHT. BUT WITH CONTINUED ONSHORE FLOW AND A FEW
RAIN/SNOW SHOWERS UPSTREAM IT IS POSSIBLE CIGS WILL DROP BACK TO
1500 FEET IN ANY SHOWERS. THE OVERALL MOIST FLOW SHOULD ALSO BRING
LEVELS BACK TO MVFR OVERNIGHT. SECOND EXCEPTION IS OVER CAPE COD AND
THE ISLANDS WHERE VFR CONDITIONS CONTINUE IN PLACE. BELIEVE THESE
CONDITIONS WILL ALSO DETERIORATE OVERNIGHT IN THE ONSHORE
NORTHEAST FLOW.

MONDAY AND MONDAY NIGHT...MODERATE CONFIDENCE. MAINLY MVFR
CONDITIONS CONTINUE IN SCATTERED LIGHT SNOW SHOWERS. LIGHT FZRA
POSSIBLE LATE MONDAY NIGHT ACROSS NW MASSACHUSETTS.

KBOS TERMINAL...MODERATE CONFIDENCE.

KBDL TERMINAL...MODERATE CONFIDENCE.

OUTLOOK...TUESDAY THROUGH FRIDAY...MODERATE CONFIDENCE

TUESDAY...MVFR CIGS AND VSBYS IN LIGHT RAIN.  EAST SOUTHEAST
WINDS...WITH FREQUENT GUSTS TO 25 KNOTS ON THE CAPE AND ISLANDS.

LATE TUESDAY NIGHT-WEDNESDAY-THURSDAY... CONDITIONS LOWERING TO
IFR/LIFR IN RAIN/HEAVY RAIN. SOUTHEAST WINDS GUSTING 25 TO 35 KNOTS
WEDNESDAY AND SOUTH WINDS SIMILAR SPEEDS WEDNESDAY NIGHT...EXCEPT 30
TO 40 KNOTS CAPE COD AND ISLANDS. WINDS AT 2000 FEET MAY REACH 55 TO
65 KNOTS BY WEDNESDAY NIGHT CREATING LOW LEVEL WIND SHEAR. ISOLATED
THUNDERSTORMS WEDNESDAY AFTERNOON AND NIGHT. COLD FRONT SWINGS
THROUGH ON THURSDAY MORNING BRINGING A WIND SHIFT TO WEST WITH GUSTS
30-40 KNOTS.  CONDITIONS IMPROVE TO VFR AFTER THE WIND SHIFT.

FRIDAY...VFR.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

HIGH PRESSURE ACROSS QUEBEC AND THE MARITIMES WILL RESULT IN
PERSISTENT NORTHEASTERLY TO EASTERLY WINDS ACROSS THE WATERS THROUGH
MONDAY.  THIS WILL RESULT IN BUILDING SEAS ON THE EASTERN WATERS
DESPITE WIND GUSTS UP TO 20 KNOTS.  SEAS BUILD TO AT LEAST 5 FEET ON
THE EASTERN WATERS BY MIDDAY MONDAY. A SMALL CRAFT ADVISORY
CONTINUES FOR THE EASTERN WATERS FOR THE PERIOD FROM MIDDAY
MONDAY THROUGH TUESDAY MORNING. WINDS INCREASE TO NEAR 25 KTS ON
THE SOUTHERN WATERS BY 12Z TUESDAY.

OUTLOOK...TUESDAY THROUGH FRIDAY...MODERATE CONFIDENCE

TUESDAY...EAST WIND GUSTING TO 25 KNOTS...BECOMING SOUTHEAST AT
NIGHT. SEAS 5 TO 7 FEET ON THE EXPOSED WATERS.  A SMALL CRAFT
ADVISORY WILL BE NEEDED.

WEDNESDAY-THURSDAY... SOUTH WINDS WITH FREQUENT GUSTS 35 TO 40 KNOTS
BY WEDNESDAY AFTERNOON AND CONTINUING THROUGH THE NIGHT. WINDS SHIFT
WEST THURSDAY MORNING WITH SIMILAR SPEEDS THROUGH THE AFTERNOON.
SEAS WILL BUILD TO 7 TO 12 FEET ON THE EXPOSED WATERS BY WEDNESDAY
NIGHT AND THURSDAY.  A GALE WARNING MAY BE NEEDED.

FRIDAY...WINDS DIMINISHING TO 25 KNOTS FRIDAY MORNING AND BELOW 25
KNOTS BY AFTERNOON.  SEAS LINGERING AT 5 TO 7 FEET ON THE EXPOSED
WATERS. A SMALL CRAFT ADVISORY MAY BE NEEDED.

&&

.TIDES/COASTAL FLOODING...
HIGH ASTRONOMICAL TIDES WILL OCCUR TUESDAY THROUGH THURSDAY.

TUESDAY...HIGH TIDE AT BOSTON WILL BE 11.6 FT. WINDS WILL BE FROM
THE EAST...SO THERE WILL BE ONSHORE FLOW DURING THIS HIGH TIDE
ALLOWING FOR MINOR SPLASHOVER. IF WINDS INCREASE THEN COULD SEE
SOME POCKETS OF MINOR COASTAL FLOODING.

WEDNESDAY...WINDS SHIFT TO A MORE SOUTHEASTERLY FLOW DURING THE DAY
AND INCREASE QUICKLY AS AN APPROACHING SYSTEM BRINGS PRESSURE
FALLS OF 1 MB/HR. THE WEDNESDAY AFTERNOON HIGH TIDE IN BOSTON IS
11.7 FT AND STRONG SOUTHEASTERLY WINDS WILL BE JUST OFFSHORE.
RIGHT NOW BELIEVE MINOR COASTAL FLOODING IS POSSIBLE ALONG THE
EAST COAST.

WEDNESDAY EVENING...SOUTHERLY WINDS ARE EXPECTED AND ASTRONOMICAL
TIDES INCREASE ALONG THE SOUTH COAST. HIGH TIDE IN PROVIDENCE WILL
BE 5.2 FT. 925 MB LLJ STRENGTHENS TO 55-65 KTS WHICH COULD PUSH A
DECENT SURGE UP ALONG THE SOUTH COAST DURING THE TIME OF HIGH
TIDE. THINKING THAT MINOR COASTAL FLOODING COULD OCCUR BUT CANNOT
RULE OUT MODERATE ALONG THE SOUTH COAST...ESPECIALLY IF LLJ
CONTINUES TO STRENGTHEN.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 4 PM MONDAY TO 7 AM EST TUESDAY FOR
     ANZ250.
     SMALL CRAFT ADVISORY FROM 10 PM MONDAY TO 7 AM EST TUESDAY FOR
     ANZ251-255.
     SMALL CRAFT ADVISORY FROM 1 PM MONDAY TO 7 AM EST TUESDAY FOR
     ANZ254.

&&

$$
SYNOPSIS...WTB/RLG
NEAR TERM...DUNTEN/RLG
SHORT TERM...RLG
LONG TERM...WTB
AVIATION...WTB/RLG
MARINE...WTB/RLG
TIDES/COASTAL FLOODING...




000
FXUS61 KBOX 212347
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
647 PM EST SUN DEC 21 2014

.SYNOPSIS...
SCATTERED SNOW/RAIN SHOWERS CONTINUE THROUGH MONDAY. WEAK LOW
PRESSURE WILL PASS SOUTH OF NEW ENGLAND BRINGING ANOTHER PERIOD OF
PRECIPITATION MONDAY NIGHT AND TUESDAY. A MUCH STRONGER STORM
PASSING WEST OF NEW ENGLAND WILL BRING HEAVY RAINFALL... GUSTY
WINDS AND COASTAL FLOODING CONCERNS TO THE REGION WEDNESDAY AND
WEDNESDAY NIGHT. DRY BUT VERY WINDY CONDITIONS FOLLOW FOR
CHRISTMAS DAY. HIGH PRESSURE BRINGS DRY WEATHER FRIDAY. ANOTHER
DEVELOPING SYSTEM MAY BRING RAIN AND SNOW NEXT SUNDAY.

&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...

645 PM UPDATE...
TWO AREAS OF LIGHT RAIN/SNOW SHOWERS ON RADAR...ONE MOVING
SOUTHWEST FROM THE GULF OF MAINE TOWARD SOUTHEAST MASS AND THE
OTHER MOVING NORTH ONTO THE SOUTH COASTS OF RI AND MASS. WE
ADJUSTED POPS TO REFLECT THE CHANCES BEING IN AREAS MAINLY SOUTH
OF THE MASS PIKE EARLY TONIGHT. AS NOTED EARLIER...THE LIGHT PCPN
SHOULD AMOUNT TO SNOW ACCUMULATIONS OF A DUSTING/COATING UP TO
POSSIBLY AN INCH IN A FEW PLACES. NO OTHER CHANGES TO THE EXISTING
FORECAST.

PREVIOUS DISCUSSION...
SHORTWAVE RIDGING BUILDS OVER SOUTHERN NEW ENGLAND OVERNIGHT. IN
ADDITION...HIGH PRESSURE IN QUEBEC BUILDS OVER THE REGION AS WELL.
THEREFORE...THERE WILL BE NO FOCUSING MECHANISM FOR PRECIP.
HOWEVER...ONSHORE FLOW AND DECENT MID LEVEL LAPSE RATES WILL ALLOW
FOR A FEW SCATTERED SNOW/RAIN SHOWERS ACROSS THE AREA OVERNIGHT.
EXPECT SNOW SHOWERS TO REMAIN ROUGHLY NORTH AND WEST OF A NEWPORT
TO TAUNTON TO SCITUATE LINE. ANY ADDITIONAL SNOWFALL WILL AMOUNT
TO A DUSTING TO ABOUT AN INCH. TEMPERATURES WILL FALL INTO THE MID
20S ACROSS THE NORTHWEST TO THE MID 30S ON THE CAPE AND ISLANDS.

&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/...
MONDAY...CLOUDY...DAMP...AND RAW CONDITIONS WILL CONTINUE THROUGH
THE DAY WITH CONTINUED ONSHORE FLOW AND SCATTERED SNOW/RAIN SHOWERS.

MONDAY NIGHT...WEAK LOW PRESSURE MOVING UP THE COAST TO JUST OFF THE
DELMARVA PENINSULA WILL PRODUCE WARM ADVECTION OVER SOUTHERN NEW
ENGLAND.  THIS IN TURN WILL LIKELY RESULT IN SOME PRECIPITATION
DEVELOPING OVERNIGHT.  HIGH PRESSURE MOVING INTO THE MARITIMES WILL
ALLOW FOR SOME COLD AIR DAMMING...PARTICULARLY INTO INTERIOR
SOUTHERN NEW ENGLAND.  THIS SCENARIO IS A GOOD SET UP FOR SOME
FREEZING RAIN ACROSS THE INTERIOR.  THE MAIN QUESTION IS HOW FAR
NORTH THE WARMER AIR GETS AS THIS WILL DETERMINE PTYPE.  FOR
NOW...WILL MAKE MENTION OF THE POTENTIAL FOR AN AREA OF FREEZING
RAIN IN THE HAZARDOUS WEATHER OUTLOOK. IF FREEZING RAIN LOOKS TO BE
MORE CERTAIN...WE WILL NEED TO ISSUE A WINTER WEATHER ADVISORY.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
BIG PICTURE...

TUESDAY STARTS WITH UPPER RIDGES ON EACH COAST AND A DEEP UPPER
TROUGH/CLOSED LOW OVER THE PLAINS. BY WEDNESDAY THE CLOSED LOW
EJECTS NORTHEAST THROUGH LAKE SUPERIOR INTO CANADA. THIS SWEEPS THE
TROUGH AXIS EAST AND PASSES ACROSS NEW ENGLAND CHRISTMAS DAY.
ANOTHER SHORTWAVE MOVES ONSHORE IN THE PACIFIC NORTHWEST WEDNESDAY
AND PHASES WITH A SECOND DROPPING SOUTH FROM NORTHERN CANADA.  THIS
REESTABLISHES THE UPPER TROUGH OVER THE NORTHERN PLAINS/GREAT LAKES
SATURDAY.

CONTOUR HEIGHTS WILL BE ABOVE NORMAL MIDWEEK...TRENDING BELOW NORMAL
OVER THE WEEKEND AS THE SECOND UPPER TROUGH SHIFTS EAST. THIS POINTS
TO A COOLING TREND AFTER CHRISTMAS.

THE GFS AND ECMWF ARE SIMILAR IN HANDLING THE HOLIDAY STORM. THERE
ARE DIFFERENCES BETWEEN THE MODELS IN HANDLING THE SUNDAY SYSTEM. WE
USED A BLEND MOST OF THE LONG TERM PERIOD...BUT MANUALLY ADJUSTED
POPS FOR SUNDAY WITH LOW CONFIDENCE IN MODEL VALUES.

THE DAILIES...

TUESDAY... HIGH PRESSURE OVER THE MARITIMES WITH RIDGING DOWN THE
ATLANTIC COAST. COASTAL LOW PRESSURE WAVE DEVELOPS ALONG STALLED
WARM FRONT AND MOVES NORTH.  AS THE COASTAL LOW MOVES NORTH IT WILL
RUN UP AGAINST THE MARITIME HIGH. THIS WILL INCREASE THE LOW LEVEL
PRESSURE GRADIENT AND INCREASE THE LOW LEVEL SOUTHEAST WINDS.
RESULT...A SOUTHEAST LOW LEVEL JET RUNS OVER THE RIDGING ALONG THE
COASTAL PLAIN INDUCING LOW LEVEL LIFT. THE MOIST LAYER EXPANDS ABOVE
800 MB...NOT DEEP BUT DEEP ENOUGH FOR THE LIFT TO GENERATE LIGHT
PCPN. PTYPE WILL BE RAIN MOST PLACES...BUT THERE COULD BE SPOTS OF
LIGHT FREEZING RAIN IN NORTHWEST MASSACHUSETTS. WE WILL MAINTAIN
CHANCE POPS BUT INCREASE TO AROUND 50 PCT...THE HIGH END OF THE
CHANCE RANGE.

LOW LEVEL SOUTH JET MOVES UP THE COAST TUESDAY NIGHT REACHING THE
COOLER AIR OVER NEW ENGLAND AFTER MIDNIGHT AND BEFORE SUNRISE. THIS
WILL GENERATE ADDITIONAL LIFT AS WELL AS INCREASING AND DEEPENING
MOISTURE. THIS SUGGESTS INCREASING POPS OVERNIGHT.  TEMPERATURES
SHOULD REMAIN ABOVE FREEZING SO PTYPE SHOULD BE RAIN.

WEDNESDAY-THURSDAY... SOUTH 40-50 KNOT LOW LEVEL JET MOVES OVER NEW
ENGLAND WEDNESDAY GENERATING STRONG LIFT AND TRANSPORTING HIGH
VALUES OF PRECIPITABLE WATER INTO THAT LIFT. THE MOISTURE VALUES ARE
MORE THAN 3 STD DEVIATIONS ABOVE NORMAL FOR DECEMBER...AND ACTUALLY
NEAR THE MAXIMUM PREVIOUSLY OBSERVED VALUE. THIS SUGGESTS RAIN WITH
SOME HEAVY DOWNPOURS. COLD FRONT APPROACHES LATE WEDNESDAY NIGHT AND
CROSSES SOUTHERN NEW ENGLAND CHRISTMAS MORNING. THE FRONT WILL HAVE
DYNAMIC SUPPORT FROM A 140-150 KNOT UPPER JET. THE FOREWARD PROGRESS
OF THE FRONT WILL SLOW BECAUSE MOST OF THE MOTION IN THE UPPER JET
WILL BE PARALLEL TO THE FRONT. THIS WILL MEAN CONTINUED RAIN/HEAVY
RAIN THROUGH THE NIGHT INTO THURSDAY MORNING.

THE OBVIOUS CONCERN FOR THIS PERIOD WILL BE FLOODING FROM HEAVY
RAINFALL. RAIN AMOUNTS OF 2 TO 3 INCHES ARE EXPECTED. THIS SHOULD BE
SUFFICIENT FOR AT LEAST URBAN AND POOR DRAINAGE FLOODING. A FLOOD
WATCH MAY BE NEEDED.

A SECOND CONCERN WILL BE WIND. THE LOW LEVEL JET WEDNESDAY WILL BE
SOUTH 40-50 KNOTS...AND INCREASE TO 55-65 KNOTS WEDNESDAY NIGHT.
CONVENTIONAL MIXING WILL NOT BE DEEP...BUT HEAVY DOWNPOURS COULD
CREATE A MOIST ADIABATIC CHANNEL THAT BRINGS DOWN SOME STRONGER WIND
GUSTS. MODEL GRIDS ARE RATHER LIGHT ON WIND GUSTS...15 TO 30 KNOTS.
WE WILL MANUALLY ADJUST THESE VALUES UP TO 25-35 KNOTS OVER LAND AND
A LITTLE STRONGER OVER WATER.

A THIRD CONCERN WILL BE COASTAL FLOODING. MORE DETAILS ON THIS IN
THE TIDE/COASTAL FLOOD SECTION.

WINDS SHIFT TO WEST BEHIND THE FRONT ON CHRISTMAS DAY. THIS WILL
BRING DRIER AIR AND SO END THE RAINFALL. COLD ADVECTION WILL PROMOTE
MIXING TO NEAR 850 MB IN THE AFTERNOON AND TAP 25-35 KNOT WIND
GUSTS...POSSIBLY 40 KNOT GUSTS. A WIND ADVISORY MAY BE NEEDED FOR
THESE WEST WINDS THURSDAY.

FRIDAY THROUGH SUNDAY.... HIGH PRESSURE MOVES OVER THE REGION FRIDAY
BRINGING DRY WEATHER.  SHORTWAVE MOVING THROUGH THE GREAT LAKES
SWINGS A COLD FRONT THROUGH NEW ENGLAND SATURDAY. THE SURFACE
REFLECTION OF THE SHORTWAVE MOVES UP THE ST LAWRENCE VALLEY AND JET
SUPPPORT WILL MOSTLY BE NORTH OF THE BORDER...SO PCPN WILL BE
LIMITED.  QUESTION FOR SUNDAY WILL BE WHETHER A WAVE FORMS ON THE
DEPARTING COLD FRONT...IF SO IT MIGHT BRING PCPN TO NEW ENGLAND. THE
ECMWF THINKS SO BUT THE GFS DOES NOT. WE BROUGHT IN A CHANCE OF RAIN
AND SNOW SHOWERS.

&&

.AVIATION /00Z MONDAY THROUGH FRIDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH MONDAY NIGHT/...

TONIGHT...MODERATE CONFIDENCE. MAINLY MVFR CONDITIONS THROUGH
TONIGHT. ONE EXCEPTION IS OVER BOSTON AND ESSEX COUNTY WHERE THE
1500 FOOT CEILING BROKE TO 6500 FEET AND MAY STAY LIKE THAT
THROUGH THE EARLY NIGHT. BUT WITH CONTINUED ONSHORE FLOW AND A FEW
RAIN/SNOW SHOWERS UPSTREAM IT IS POSSIBLE CIGS WILL DROP BACK TO
1500 FEET IN ANY SHOWERS. THE OVERALL MOIST FLOW SHOULD ALSO BRING
LEVELS BACK TO MVFR OVERNIGHT. SECOND EXCEPTION IS OVER CAPE COD AND
THE ISLANDS WHERE VFR CONDITIONS CONTINUE IN PLACE. BELIEVE THESE
CONDITIONS WILL ALSO DETERIORATE OVERNIGHT IN THE ONSHORE
NORTHEAST FLOW.

MONDAY AND MONDAY NIGHT...MODERATE CONFIDENCE. MAINLY MVFR
CONDITIONS CONTINUE IN SCATTERED LIGHT SNOW SHOWERS. LIGHT FZRA
POSSIBLE LATE MONDAY NIGHT ACROSS NW MASSACHUSETTS.

KBOS TERMINAL...MODERATE CONFIDENCE.

KBDL TERMINAL...MODERATE CONFIDENCE.

OUTLOOK...TUESDAY THROUGH FRIDAY...MODERATE CONFIDENCE

TUESDAY...MVFR CIGS AND VSBYS IN LIGHT RAIN.  EAST SOUTHEAST
WINDS...WITH FREQUENT GUSTS TO 25 KNOTS ON THE CAPE AND ISLANDS.

LATE TUESDAY NIGHT-WEDNESDAY-THURSDAY... CONDITIONS LOWERING TO
IFR/LIFR IN RAIN/HEAVY RAIN. SOUTHEAST WINDS GUSTING 25 TO 35 KNOTS
WEDNESDAY AND SOUTH WINDS SIMILAR SPEEDS WEDNESDAY NIGHT...EXCEPT 30
TO 40 KNOTS CAPE COD AND ISLANDS. WINDS AT 2000 FEET MAY REACH 55 TO
65 KNOTS BY WEDNESDAY NIGHT CREATING LOW LEVEL WIND SHEAR. ISOLATED
THUNDERSTORMS WEDNESDAY AFTERNOON AND NIGHT. COLD FRONT SWINGS
THROUGH ON THURSDAY MORNING BRINGING A WIND SHIFT TO WEST WITH GUSTS
30-40 KNOTS.  CONDITIONS IMPROVE TO VFR AFTER THE WIND SHIFT.

FRIDAY...VFR.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

HIGH PRESSURE ACROSS QUEBEC AND THE MARITIMES WILL RESULT IN
PERSISTENT NORTHEASTERLY TO EASTERLY WINDS ACROSS THE WATERS THROUGH
MONDAY.  THIS WILL RESULT IN BUILDING SEAS ON THE EASTERN WATERS
DESPITE WIND GUSTS UP TO 20 KNOTS.  SEAS BUILD TO AT LEAST 5 FEET ON
THE EASTERN WATERS BY MIDDAY MONDAY. A SMALL CRAFT ADVISORY
CONTINUES FOR THE EASTERN WATERS FOR THE PERIOD FROM MIDDAY
MONDAY THROUGH TUESDAY MORNING. WINDS INCREASE TO NEAR 25 KTS ON
THE SOUTHERN WATERS BY 12Z TUESDAY.

OUTLOOK...TUESDAY THROUGH FRIDAY...MODERATE CONFIDENCE

TUESDAY...EAST WIND GUSTING TO 25 KNOTS...BECOMING SOUTHEAST AT
NIGHT. SEAS 5 TO 7 FEET ON THE EXPOSED WATERS.  A SMALL CRAFT
ADVISORY WILL BE NEEDED.

WEDNESDAY-THURSDAY... SOUTH WINDS WITH FREQUENT GUSTS 35 TO 40 KNOTS
BY WEDNESDAY AFTERNOON AND CONTINUING THROUGH THE NIGHT. WINDS SHIFT
WEST THURSDAY MORNING WITH SIMILAR SPEEDS THROUGH THE AFTERNOON.
SEAS WILL BUILD TO 7 TO 12 FEET ON THE EXPOSED WATERS BY WEDNESDAY
NIGHT AND THURSDAY.  A GALE WARNING MAY BE NEEDED.

FRIDAY...WINDS DIMINISHING TO 25 KNOTS FRIDAY MORNING AND BELOW 25
KNOTS BY AFTERNOON.  SEAS LINGERING AT 5 TO 7 FEET ON THE EXPOSED
WATERS. A SMALL CRAFT ADVISORY MAY BE NEEDED.

&&

.TIDES/COASTAL FLOODING...
HIGH ASTRONOMICAL TIDES WILL OCCUR TUESDAY THROUGH THURSDAY.

TUESDAY...HIGH TIDE AT BOSTON WILL BE 11.6 FT. WINDS WILL BE FROM
THE EAST...SO THERE WILL BE ONSHORE FLOW DURING THIS HIGH TIDE
ALLOWING FOR MINOR SPLASHOVER. IF WINDS INCREASE THEN COULD SEE
SOME POCKETS OF MINOR COASTAL FLOODING.

WEDNESDAY...WINDS SHIFT TO A MORE SOUTHEASTERLY FLOW DURING THE DAY
AND INCREASE QUICKLY AS AN APPROACHING SYSTEM BRINGS PRESSURE
FALLS OF 1 MB/HR. THE WEDNESDAY AFTERNOON HIGH TIDE IN BOSTON IS
11.7 FT AND STRONG SOUTHEASTERLY WINDS WILL BE JUST OFFSHORE.
RIGHT NOW BELIEVE MINOR COASTAL FLOODING IS POSSIBLE ALONG THE
EAST COAST.

WEDNESDAY EVENING...SOUTHERLY WINDS ARE EXPECTED AND ASTRONOMICAL
TIDES INCREASE ALONG THE SOUTH COAST. HIGH TIDE IN PROVIDENCE WILL
BE 5.2 FT. 925 MB LLJ STRENGTHENS TO 55-65 KTS WHICH COULD PUSH A
DECENT SURGE UP ALONG THE SOUTH COAST DURING THE TIME OF HIGH
TIDE. THINKING THAT MINOR COASTAL FLOODING COULD OCCUR BUT CANNOT
RULE OUT MODERATE ALONG THE SOUTH COAST...ESPECIALLY IF LLJ
CONTINUES TO STRENGTHEN.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 4 PM MONDAY TO 7 AM EST TUESDAY FOR
     ANZ250.
     SMALL CRAFT ADVISORY FROM 10 PM MONDAY TO 7 AM EST TUESDAY FOR
     ANZ251-255.
     SMALL CRAFT ADVISORY FROM 1 PM MONDAY TO 7 AM EST TUESDAY FOR
     ANZ254.

&&

$$
SYNOPSIS...WTB/RLG
NEAR TERM...WTB/RLG
SHORT TERM...RLG
LONG TERM...WTB
AVIATION...WTB/RLG
MARINE...WTB/RLG
TIDES/COASTAL FLOODING...RLG



000
FXUS61 KBOX 212347
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
647 PM EST SUN DEC 21 2014

.SYNOPSIS...
SCATTERED SNOW/RAIN SHOWERS CONTINUE THROUGH MONDAY. WEAK LOW
PRESSURE WILL PASS SOUTH OF NEW ENGLAND BRINGING ANOTHER PERIOD OF
PRECIPITATION MONDAY NIGHT AND TUESDAY. A MUCH STRONGER STORM
PASSING WEST OF NEW ENGLAND WILL BRING HEAVY RAINFALL... GUSTY
WINDS AND COASTAL FLOODING CONCERNS TO THE REGION WEDNESDAY AND
WEDNESDAY NIGHT. DRY BUT VERY WINDY CONDITIONS FOLLOW FOR
CHRISTMAS DAY. HIGH PRESSURE BRINGS DRY WEATHER FRIDAY. ANOTHER
DEVELOPING SYSTEM MAY BRING RAIN AND SNOW NEXT SUNDAY.

&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...

645 PM UPDATE...
TWO AREAS OF LIGHT RAIN/SNOW SHOWERS ON RADAR...ONE MOVING
SOUTHWEST FROM THE GULF OF MAINE TOWARD SOUTHEAST MASS AND THE
OTHER MOVING NORTH ONTO THE SOUTH COASTS OF RI AND MASS. WE
ADJUSTED POPS TO REFLECT THE CHANCES BEING IN AREAS MAINLY SOUTH
OF THE MASS PIKE EARLY TONIGHT. AS NOTED EARLIER...THE LIGHT PCPN
SHOULD AMOUNT TO SNOW ACCUMULATIONS OF A DUSTING/COATING UP TO
POSSIBLY AN INCH IN A FEW PLACES. NO OTHER CHANGES TO THE EXISTING
FORECAST.

PREVIOUS DISCUSSION...
SHORTWAVE RIDGING BUILDS OVER SOUTHERN NEW ENGLAND OVERNIGHT. IN
ADDITION...HIGH PRESSURE IN QUEBEC BUILDS OVER THE REGION AS WELL.
THEREFORE...THERE WILL BE NO FOCUSING MECHANISM FOR PRECIP.
HOWEVER...ONSHORE FLOW AND DECENT MID LEVEL LAPSE RATES WILL ALLOW
FOR A FEW SCATTERED SNOW/RAIN SHOWERS ACROSS THE AREA OVERNIGHT.
EXPECT SNOW SHOWERS TO REMAIN ROUGHLY NORTH AND WEST OF A NEWPORT
TO TAUNTON TO SCITUATE LINE. ANY ADDITIONAL SNOWFALL WILL AMOUNT
TO A DUSTING TO ABOUT AN INCH. TEMPERATURES WILL FALL INTO THE MID
20S ACROSS THE NORTHWEST TO THE MID 30S ON THE CAPE AND ISLANDS.

&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/...
MONDAY...CLOUDY...DAMP...AND RAW CONDITIONS WILL CONTINUE THROUGH
THE DAY WITH CONTINUED ONSHORE FLOW AND SCATTERED SNOW/RAIN SHOWERS.

MONDAY NIGHT...WEAK LOW PRESSURE MOVING UP THE COAST TO JUST OFF THE
DELMARVA PENINSULA WILL PRODUCE WARM ADVECTION OVER SOUTHERN NEW
ENGLAND.  THIS IN TURN WILL LIKELY RESULT IN SOME PRECIPITATION
DEVELOPING OVERNIGHT.  HIGH PRESSURE MOVING INTO THE MARITIMES WILL
ALLOW FOR SOME COLD AIR DAMMING...PARTICULARLY INTO INTERIOR
SOUTHERN NEW ENGLAND.  THIS SCENARIO IS A GOOD SET UP FOR SOME
FREEZING RAIN ACROSS THE INTERIOR.  THE MAIN QUESTION IS HOW FAR
NORTH THE WARMER AIR GETS AS THIS WILL DETERMINE PTYPE.  FOR
NOW...WILL MAKE MENTION OF THE POTENTIAL FOR AN AREA OF FREEZING
RAIN IN THE HAZARDOUS WEATHER OUTLOOK. IF FREEZING RAIN LOOKS TO BE
MORE CERTAIN...WE WILL NEED TO ISSUE A WINTER WEATHER ADVISORY.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
BIG PICTURE...

TUESDAY STARTS WITH UPPER RIDGES ON EACH COAST AND A DEEP UPPER
TROUGH/CLOSED LOW OVER THE PLAINS. BY WEDNESDAY THE CLOSED LOW
EJECTS NORTHEAST THROUGH LAKE SUPERIOR INTO CANADA. THIS SWEEPS THE
TROUGH AXIS EAST AND PASSES ACROSS NEW ENGLAND CHRISTMAS DAY.
ANOTHER SHORTWAVE MOVES ONSHORE IN THE PACIFIC NORTHWEST WEDNESDAY
AND PHASES WITH A SECOND DROPPING SOUTH FROM NORTHERN CANADA.  THIS
REESTABLISHES THE UPPER TROUGH OVER THE NORTHERN PLAINS/GREAT LAKES
SATURDAY.

CONTOUR HEIGHTS WILL BE ABOVE NORMAL MIDWEEK...TRENDING BELOW NORMAL
OVER THE WEEKEND AS THE SECOND UPPER TROUGH SHIFTS EAST. THIS POINTS
TO A COOLING TREND AFTER CHRISTMAS.

THE GFS AND ECMWF ARE SIMILAR IN HANDLING THE HOLIDAY STORM. THERE
ARE DIFFERENCES BETWEEN THE MODELS IN HANDLING THE SUNDAY SYSTEM. WE
USED A BLEND MOST OF THE LONG TERM PERIOD...BUT MANUALLY ADJUSTED
POPS FOR SUNDAY WITH LOW CONFIDENCE IN MODEL VALUES.

THE DAILIES...

TUESDAY... HIGH PRESSURE OVER THE MARITIMES WITH RIDGING DOWN THE
ATLANTIC COAST. COASTAL LOW PRESSURE WAVE DEVELOPS ALONG STALLED
WARM FRONT AND MOVES NORTH.  AS THE COASTAL LOW MOVES NORTH IT WILL
RUN UP AGAINST THE MARITIME HIGH. THIS WILL INCREASE THE LOW LEVEL
PRESSURE GRADIENT AND INCREASE THE LOW LEVEL SOUTHEAST WINDS.
RESULT...A SOUTHEAST LOW LEVEL JET RUNS OVER THE RIDGING ALONG THE
COASTAL PLAIN INDUCING LOW LEVEL LIFT. THE MOIST LAYER EXPANDS ABOVE
800 MB...NOT DEEP BUT DEEP ENOUGH FOR THE LIFT TO GENERATE LIGHT
PCPN. PTYPE WILL BE RAIN MOST PLACES...BUT THERE COULD BE SPOTS OF
LIGHT FREEZING RAIN IN NORTHWEST MASSACHUSETTS. WE WILL MAINTAIN
CHANCE POPS BUT INCREASE TO AROUND 50 PCT...THE HIGH END OF THE
CHANCE RANGE.

LOW LEVEL SOUTH JET MOVES UP THE COAST TUESDAY NIGHT REACHING THE
COOLER AIR OVER NEW ENGLAND AFTER MIDNIGHT AND BEFORE SUNRISE. THIS
WILL GENERATE ADDITIONAL LIFT AS WELL AS INCREASING AND DEEPENING
MOISTURE. THIS SUGGESTS INCREASING POPS OVERNIGHT.  TEMPERATURES
SHOULD REMAIN ABOVE FREEZING SO PTYPE SHOULD BE RAIN.

WEDNESDAY-THURSDAY... SOUTH 40-50 KNOT LOW LEVEL JET MOVES OVER NEW
ENGLAND WEDNESDAY GENERATING STRONG LIFT AND TRANSPORTING HIGH
VALUES OF PRECIPITABLE WATER INTO THAT LIFT. THE MOISTURE VALUES ARE
MORE THAN 3 STD DEVIATIONS ABOVE NORMAL FOR DECEMBER...AND ACTUALLY
NEAR THE MAXIMUM PREVIOUSLY OBSERVED VALUE. THIS SUGGESTS RAIN WITH
SOME HEAVY DOWNPOURS. COLD FRONT APPROACHES LATE WEDNESDAY NIGHT AND
CROSSES SOUTHERN NEW ENGLAND CHRISTMAS MORNING. THE FRONT WILL HAVE
DYNAMIC SUPPORT FROM A 140-150 KNOT UPPER JET. THE FOREWARD PROGRESS
OF THE FRONT WILL SLOW BECAUSE MOST OF THE MOTION IN THE UPPER JET
WILL BE PARALLEL TO THE FRONT. THIS WILL MEAN CONTINUED RAIN/HEAVY
RAIN THROUGH THE NIGHT INTO THURSDAY MORNING.

THE OBVIOUS CONCERN FOR THIS PERIOD WILL BE FLOODING FROM HEAVY
RAINFALL. RAIN AMOUNTS OF 2 TO 3 INCHES ARE EXPECTED. THIS SHOULD BE
SUFFICIENT FOR AT LEAST URBAN AND POOR DRAINAGE FLOODING. A FLOOD
WATCH MAY BE NEEDED.

A SECOND CONCERN WILL BE WIND. THE LOW LEVEL JET WEDNESDAY WILL BE
SOUTH 40-50 KNOTS...AND INCREASE TO 55-65 KNOTS WEDNESDAY NIGHT.
CONVENTIONAL MIXING WILL NOT BE DEEP...BUT HEAVY DOWNPOURS COULD
CREATE A MOIST ADIABATIC CHANNEL THAT BRINGS DOWN SOME STRONGER WIND
GUSTS. MODEL GRIDS ARE RATHER LIGHT ON WIND GUSTS...15 TO 30 KNOTS.
WE WILL MANUALLY ADJUST THESE VALUES UP TO 25-35 KNOTS OVER LAND AND
A LITTLE STRONGER OVER WATER.

A THIRD CONCERN WILL BE COASTAL FLOODING. MORE DETAILS ON THIS IN
THE TIDE/COASTAL FLOOD SECTION.

WINDS SHIFT TO WEST BEHIND THE FRONT ON CHRISTMAS DAY. THIS WILL
BRING DRIER AIR AND SO END THE RAINFALL. COLD ADVECTION WILL PROMOTE
MIXING TO NEAR 850 MB IN THE AFTERNOON AND TAP 25-35 KNOT WIND
GUSTS...POSSIBLY 40 KNOT GUSTS. A WIND ADVISORY MAY BE NEEDED FOR
THESE WEST WINDS THURSDAY.

FRIDAY THROUGH SUNDAY.... HIGH PRESSURE MOVES OVER THE REGION FRIDAY
BRINGING DRY WEATHER.  SHORTWAVE MOVING THROUGH THE GREAT LAKES
SWINGS A COLD FRONT THROUGH NEW ENGLAND SATURDAY. THE SURFACE
REFLECTION OF THE SHORTWAVE MOVES UP THE ST LAWRENCE VALLEY AND JET
SUPPPORT WILL MOSTLY BE NORTH OF THE BORDER...SO PCPN WILL BE
LIMITED.  QUESTION FOR SUNDAY WILL BE WHETHER A WAVE FORMS ON THE
DEPARTING COLD FRONT...IF SO IT MIGHT BRING PCPN TO NEW ENGLAND. THE
ECMWF THINKS SO BUT THE GFS DOES NOT. WE BROUGHT IN A CHANCE OF RAIN
AND SNOW SHOWERS.

&&

.AVIATION /00Z MONDAY THROUGH FRIDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH MONDAY NIGHT/...

TONIGHT...MODERATE CONFIDENCE. MAINLY MVFR CONDITIONS THROUGH
TONIGHT. ONE EXCEPTION IS OVER BOSTON AND ESSEX COUNTY WHERE THE
1500 FOOT CEILING BROKE TO 6500 FEET AND MAY STAY LIKE THAT
THROUGH THE EARLY NIGHT. BUT WITH CONTINUED ONSHORE FLOW AND A FEW
RAIN/SNOW SHOWERS UPSTREAM IT IS POSSIBLE CIGS WILL DROP BACK TO
1500 FEET IN ANY SHOWERS. THE OVERALL MOIST FLOW SHOULD ALSO BRING
LEVELS BACK TO MVFR OVERNIGHT. SECOND EXCEPTION IS OVER CAPE COD AND
THE ISLANDS WHERE VFR CONDITIONS CONTINUE IN PLACE. BELIEVE THESE
CONDITIONS WILL ALSO DETERIORATE OVERNIGHT IN THE ONSHORE
NORTHEAST FLOW.

MONDAY AND MONDAY NIGHT...MODERATE CONFIDENCE. MAINLY MVFR
CONDITIONS CONTINUE IN SCATTERED LIGHT SNOW SHOWERS. LIGHT FZRA
POSSIBLE LATE MONDAY NIGHT ACROSS NW MASSACHUSETTS.

KBOS TERMINAL...MODERATE CONFIDENCE.

KBDL TERMINAL...MODERATE CONFIDENCE.

OUTLOOK...TUESDAY THROUGH FRIDAY...MODERATE CONFIDENCE

TUESDAY...MVFR CIGS AND VSBYS IN LIGHT RAIN.  EAST SOUTHEAST
WINDS...WITH FREQUENT GUSTS TO 25 KNOTS ON THE CAPE AND ISLANDS.

LATE TUESDAY NIGHT-WEDNESDAY-THURSDAY... CONDITIONS LOWERING TO
IFR/LIFR IN RAIN/HEAVY RAIN. SOUTHEAST WINDS GUSTING 25 TO 35 KNOTS
WEDNESDAY AND SOUTH WINDS SIMILAR SPEEDS WEDNESDAY NIGHT...EXCEPT 30
TO 40 KNOTS CAPE COD AND ISLANDS. WINDS AT 2000 FEET MAY REACH 55 TO
65 KNOTS BY WEDNESDAY NIGHT CREATING LOW LEVEL WIND SHEAR. ISOLATED
THUNDERSTORMS WEDNESDAY AFTERNOON AND NIGHT. COLD FRONT SWINGS
THROUGH ON THURSDAY MORNING BRINGING A WIND SHIFT TO WEST WITH GUSTS
30-40 KNOTS.  CONDITIONS IMPROVE TO VFR AFTER THE WIND SHIFT.

FRIDAY...VFR.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

HIGH PRESSURE ACROSS QUEBEC AND THE MARITIMES WILL RESULT IN
PERSISTENT NORTHEASTERLY TO EASTERLY WINDS ACROSS THE WATERS THROUGH
MONDAY.  THIS WILL RESULT IN BUILDING SEAS ON THE EASTERN WATERS
DESPITE WIND GUSTS UP TO 20 KNOTS.  SEAS BUILD TO AT LEAST 5 FEET ON
THE EASTERN WATERS BY MIDDAY MONDAY. A SMALL CRAFT ADVISORY
CONTINUES FOR THE EASTERN WATERS FOR THE PERIOD FROM MIDDAY
MONDAY THROUGH TUESDAY MORNING. WINDS INCREASE TO NEAR 25 KTS ON
THE SOUTHERN WATERS BY 12Z TUESDAY.

OUTLOOK...TUESDAY THROUGH FRIDAY...MODERATE CONFIDENCE

TUESDAY...EAST WIND GUSTING TO 25 KNOTS...BECOMING SOUTHEAST AT
NIGHT. SEAS 5 TO 7 FEET ON THE EXPOSED WATERS.  A SMALL CRAFT
ADVISORY WILL BE NEEDED.

WEDNESDAY-THURSDAY... SOUTH WINDS WITH FREQUENT GUSTS 35 TO 40 KNOTS
BY WEDNESDAY AFTERNOON AND CONTINUING THROUGH THE NIGHT. WINDS SHIFT
WEST THURSDAY MORNING WITH SIMILAR SPEEDS THROUGH THE AFTERNOON.
SEAS WILL BUILD TO 7 TO 12 FEET ON THE EXPOSED WATERS BY WEDNESDAY
NIGHT AND THURSDAY.  A GALE WARNING MAY BE NEEDED.

FRIDAY...WINDS DIMINISHING TO 25 KNOTS FRIDAY MORNING AND BELOW 25
KNOTS BY AFTERNOON.  SEAS LINGERING AT 5 TO 7 FEET ON THE EXPOSED
WATERS. A SMALL CRAFT ADVISORY MAY BE NEEDED.

&&

.TIDES/COASTAL FLOODING...
HIGH ASTRONOMICAL TIDES WILL OCCUR TUESDAY THROUGH THURSDAY.

TUESDAY...HIGH TIDE AT BOSTON WILL BE 11.6 FT. WINDS WILL BE FROM
THE EAST...SO THERE WILL BE ONSHORE FLOW DURING THIS HIGH TIDE
ALLOWING FOR MINOR SPLASHOVER. IF WINDS INCREASE THEN COULD SEE
SOME POCKETS OF MINOR COASTAL FLOODING.

WEDNESDAY...WINDS SHIFT TO A MORE SOUTHEASTERLY FLOW DURING THE DAY
AND INCREASE QUICKLY AS AN APPROACHING SYSTEM BRINGS PRESSURE
FALLS OF 1 MB/HR. THE WEDNESDAY AFTERNOON HIGH TIDE IN BOSTON IS
11.7 FT AND STRONG SOUTHEASTERLY WINDS WILL BE JUST OFFSHORE.
RIGHT NOW BELIEVE MINOR COASTAL FLOODING IS POSSIBLE ALONG THE
EAST COAST.

WEDNESDAY EVENING...SOUTHERLY WINDS ARE EXPECTED AND ASTRONOMICAL
TIDES INCREASE ALONG THE SOUTH COAST. HIGH TIDE IN PROVIDENCE WILL
BE 5.2 FT. 925 MB LLJ STRENGTHENS TO 55-65 KTS WHICH COULD PUSH A
DECENT SURGE UP ALONG THE SOUTH COAST DURING THE TIME OF HIGH
TIDE. THINKING THAT MINOR COASTAL FLOODING COULD OCCUR BUT CANNOT
RULE OUT MODERATE ALONG THE SOUTH COAST...ESPECIALLY IF LLJ
CONTINUES TO STRENGTHEN.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 4 PM MONDAY TO 7 AM EST TUESDAY FOR
     ANZ250.
     SMALL CRAFT ADVISORY FROM 10 PM MONDAY TO 7 AM EST TUESDAY FOR
     ANZ251-255.
     SMALL CRAFT ADVISORY FROM 1 PM MONDAY TO 7 AM EST TUESDAY FOR
     ANZ254.

&&

$$
SYNOPSIS...WTB/RLG
NEAR TERM...WTB/RLG
SHORT TERM...RLG
LONG TERM...WTB
AVIATION...WTB/RLG
MARINE...WTB/RLG
TIDES/COASTAL FLOODING...RLG




000
FXUS61 KGYX 212225
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
525 PM EST SUN DEC 21 2014

.SYNOPSIS...
AN ONSHORE FLOW MAY TRIGGER SOME FLURRIES OR LIGHT SNOW MAINLY OVER
SOUTHERN REGIONS RIGHT THROUGH TUESDAY. A SIGNIFICANT LOW
PRESSURE SYSTEM SYSTEM WILL GRADUALLY ORGANIZE WEDNESDAY...BEFORE
MOVING OVER THE GREAT LAKES. THIS COULD BRING WINDY CONDITIONS AND
THE POTENTIAL FOR HEAVY RAIN AROUND CHRISTMAS EVE INTO EARLY
CHRISTMAS MORNING. ANOTHER LOW PRESSURE SYSTEM WILL PASS BY TO OUR
NORTHWEST LATE IN THE WEEK AND EARLY NEXT WEEKEND.

&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
AREAS OF LIGHT SNOW WILL CONTINUE INTO THIS EVENING HOURS
ASSOCIATED WITH "OCEAN EFFECT" ONSHORE FLOW...AND ALSO DUE TO THE
PROXIMITY OF A WEAK MID LEVEL LOW. IN GENERAL...WILL BE LOWERING
POPS AS WE HEAD INTO THE LATE EVENING HOURS...WITH THE GREATEST
CHANCE OF A SNOW SHOWERS ALONG AND NEAR THE COASTLINE. THE BEACH
AREAS WILL NEED TO BE MONITORED HOWEVER...AS THERE IS SOME
INDICATION OF A WEAK NORLUN TROUGH OVER THE REGION.

&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/...
SCATTERED SNOW SHOWERS AND FLURRIES WILL CONTINUE RIGHT THROUGH
MONDAY NIGHT OVER SOUTHERN AREAS DUE TO A PERSISTENT NORTHEAST
FLOW OVER THE MOIST GULF OF MAINE. MESO MODELS WITHIN THE 12Z
MODEL SUITE CONTINUE TO HAVE A DIFFICULT TIME PICKING UP ON THIS
LOW LEVEL MOISTURE AND PRECIP. HAVE THEREFORE RAISED POPS ABOVE
ALL AVAILABLE GUIDANCE.

A COLD AIR DAMMING SIGNATURE WILL BE FORMING BY MONDAY NIGHT.
THEREFORE...THE PTYPE SHOULD BE ALL SNOW THROUGH THE SHORT TERM
PORTION OF THE FORECAST...BEFORE THE WARM AIR POURS INTO THE
REGION.

&&

.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
THE WEAK ONSHORE FLOW CONTINUES INTO TUESDAY WITH LOW LEVEL
MOISTURE DEEPEST ALONG THE COAST. ON TUESDAY THE WARMER ONSHORE
FLOW DEEPENS AS THE HIGH MOVES FURTHER OFFSHORE ALLOWING A
SOUTHEAST FLOW TO INCREASE...SO SCATTERED LIGHT INTERMITTENT
PRECIPITATION EXPECTED...MOSTLY IN THE FORM OF RAIN EXCEPT SOME
IN THE FORM OF LIGHT SNOW IN THE MOUNTAINS BEFORE CHANGING OVER TO
RAIN EVEN IN THOSE AREAS. THE MAIN EVENT WILL BE THE ONSET OF THE
HEAVIER PRECIPITATION LATE TUESDAY NIGHT AND ESPECIALLY CHRISTMAS
EVE WHERE THE RAIN WILL BECOME HEAVY AT TIMES AS A STRONG WARM
ADVECTION PATTERN DEVELOPS BEING ACCOMPANIED BY A STRONG LOW/MID
LEVEL JET. THE MAIN UPPER LOW PASSES WELL TO OUR WEST AS IT MOVES
THROUGH THE GREAT LAKES. QPF TOTALS FOR LATE TUESDAY INTO THURSDAY
COULD BE IN THE 2-4 INCH RANGE. DUE TO VERY WARM AIR THIS WILL BE
IN THE FORM OF RAIN EVEN IN THE MOUNTAINS. SOME FLOODING PROBLEMS
MAY ARISE IN THE HEADWATERS BY WEDNESDAY NIGHT OR THURSDAY DUE TO
THE COMBINATION OF SOME SNOWMELT AND THE HEAVY RAINS. ALL MODELS
AGREE ON MILD TEMPERATURES...USED A BLEND OF THE MODELS.

SYSTEM FINALLY EXITS TO THE NORTHEAST BY THURSDAY AFTERNOON AS A
DRY SLOT MOVES ACROSS THE AREA FOLLOWED BY A COLD FRONT WITH A
RETURN TO SEASONAL TEMPS FOR FRI.

ANOTHER SYSTEM WHICH WILL BE WEAKER WILL APPROACH FOR THE WEEKEND.
MODELS DIFFER IN RUN TO RUN CONTINUITY AND ALSO VARIANCES IN
TIMING, STRENGTH, AND POSITION OF THIS SYSTEM. FOR NOW WILL BROAD
BRUSH DUE TO ALL THE UNCERTAINTY AS WELL AS PTYPE.

&&

.AVIATION /00Z MONDAY THROUGH FRIDAY/...
SHORT TERM...MAINLY VFR THROUGH MONDAY NIGHT...HOWEVER THERE MAY
BE BRIEFLY MVFR CONDITIONS IN SCATTERED SNOW SHOWERS SOUTHERN
LOCATIONS.

LONG TERM...MVFR CONDS EXPECTED TUE AND THEN LOWERING TO IFR TUE
NIGHT AND LIFR CONDITIONS WED INTO THU. CONDITIONS IMPROVE BY LATE
THU TO VFR.

&&

.MARINE...
SHORT TERM...WINDS AND SEAS WILL REMAIN MOSTLY OUT OF THE
NORTHEAST THROUGH MONDAY NIGHT. WINDS AND SEAS WILL REMAIN BELOW
SCA CONDITIONS.

LONG TERM...STRONG LOW PRESSURE WILL MOVE WELL TO THE WEST AND
WILL CAUSE WINDS TO INCREASE TO GALES TUESDAY NIGHT THROUGH
WEDNESDAY WITH BORDERLINE STORM FORCE WIND GUSTS POSSIBLE
WEDNESDAY NIGHT. SEAS COULD BUILD IN EXCESS OF 15 FT OVER THE
OUTER WATERS BY WEDNESDAY NIGHT OR EARLY THURSDAY. GUIDANCE LOOKS
LOW ON BOTH WINDS AND SEAS WHICH IS TYPICAL FOR THESE TYPE OF
EVENTS.

&&

.HYDROLOGY...
MODELS CONTINUE TO BACK OFF ON RAINFALL TOTALS FOR
THE CHRISTMAS EVE/EARLY CHRISTMAS MORNING EVENT...BUT AREA STILL
IN THE 1 TO 3 INCH RANGE. HOPING THE SNOWPACK IN THE MOUNTAINS AND
FOOTHILLS WILL TAKE IN SOME OF THE 1 TO 2 INCH RAINFALL AMOUNTS IN
THAT AREA...BUT STILL EXPECTED RAPID RISES IN THE HEADWATERS. OVER
SOUTHERN LOCATIONS...2 TO 3 INCHES OF RAIN EXPECTED. IN ANY
CASE...FLOODING IS A DISTINCT POSSIBLY CHRISTMAS EVE AND CHRISTMAS
MORNING ASSOCIATED WITH THE HEAVY RAIN AND SNOWMELT.

&&

.TIDES/COASTAL FLOODING...
ASTRONOMICAL TIDES ARE AT THEIR PEAK FOR THE MONTH. THIS...IN
COMBINATION WITH STRONG SOUTHERLY DEVELOPING GALES (WITH POSSIBLE
STORM FORCE GUSTS) WILL LIKELY ALLOW FOR ABOUT A 1 FOOT STORM
SURGE. WITH BUILDING WAVES IN THE 15 FOOT RANGE...EXPECT A FEW
AREAS TO HAVE COASTAL FLOODING...SPLASH-OVER AND BEACH EROSION.

NART WAVE RUN-UP MATRICES ARE ALREADY PREDICTING THE POTENTIAL FOR
COASTAL FLOODING...OVERWASH AND EROSION ACROSS MOST LOCATIONS IN
MAINE AND NEW HAMPSHIRE BASED ON OUR CURRENT STORM SURGE AND WAVE
PREDICTIONS.

THE QUESTION IS HOWEVER...WHEN WILL THE PEAK WINDS AND SEAS
ARRIVE? RIGHT NOW IT IS TOO EARLY TO TELL IF THIS PERIOD OF
INCLEMENT WEATHER/OCEAN CONDITIONS WILL ARRIVE NEAR THE TIME OF
HIGH TIDE. THE MIDDAY TIDES ON CHRISTMAS EVE AND CHRISTMAS DAY ARE
THE HIGHEST AT 11 FEET...WHILE THE 1 AM CHRISTMAS MORNING HIGH
TIDE IS LOWER AT 10 FEET.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.

&&

$$




000
FXUS61 KBOX 212056
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
356 PM EST SUN DEC 21 2014

.SYNOPSIS...
SCATTERED SNOW/RAIN SHOWERS CONTINUE THROUGH MONDAY. WEAK LOW
PRESSURE WILL PASS SOUTH OF NEW ENGLAND BRINGING ANOTHER PERIOD OF
PRECIPITATION MONDAY NIGHT AND TUESDAY. A MUCH STRONGER STORM
PASSING WEST OF NEW ENGLAND WILL BRING HEAVY RAINFALL... GUSTY
WINDS AND COASTAL FLOODING CONCERNS TO THE REGION WEDNESDAY AND
WEDNESDAY NIGHT. DRY BUT VERY WINDY CONDITIONS FOLLOW FOR
CHRISTMAS DAY. HIGH PRESSURE BRINGS DRY WEATHER FRIDAY. ANOTHER
DEVELOPING SYSTEM MAY BRING RAIN AND SNOW NEXT SUNDAY.

&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
SHORTWAVE RIDGING BUILDS OVER SOUTHERN NEW ENGLAND OVERNIGHT. IN
ADDITION...HIGH PRESSURE IN QUEBEC BUILDS OVER THE REGION AS WELL.
THEREFORE...THERE WILL BE NO FOCUSING MECHANISM FOR PRECIP.
HOWEVER...ONSHORE FLOW AND DECENT MID LEVEL LAPSE RATES WILL ALLOW
FOR A FEW SCATTERED SNOW/RAIN SHOWERS ACROSS THE AREA OVERNIGHT.
EXPECT SNOW SHOWERS TO REMAIN ROUGHLY NORTH AND WEST OF A NEWPORT TO
TAUNTON TO SCITUATE LINE.  ANY ADDITIONAL SNOWFALL WILL AMOUNT TO A
DUSTING TO ABOUT AN INCH. TEMPERATURES WILL FALL INTO THE MID 20S
ACROSS THE NORTHWEST TO THE MID 30S ON THE CAPE AND ISLANDS.

&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/...
MONDAY...CLOUDY...DAMP...AND RAW CONDITIONS WILL CONTINUE THROUGH
THE DAY WITH CONTINUED ONSHORE FLOW AND SCATTERED SNOW/RAIN SHOWERS.

MONDAY NIGHT...WEAK LOW PRESSURE MOVING UP THE COAST TO JUST OFF THE
DELMARVA PENINSULA WILL PRODUCE WARM ADVECTION OVER SOUTHERN NEW
ENGLAND.  THIS IN TURN WILL LIKELY RESULT IN SOME PRECIPITATION
DEVELOPING OVERNIGHT.  HIGH PRESSURE MOVING INTO THE MARITIMES WILL
ALLOW FOR SOME COLD AIR DAMMING...PARTICULARLY INTO INTERIOR
SOUTHERN NEW ENGLAND.  THIS SCENARIO IS A GOOD SET UP FOR SOME
FREEZING RAIN ACROSS THE INTERIOR.  THE MAIN QUESTION IS HOW FAR
NORTH THE WARMER AIR GETS AS THIS WILL DETERMINE PTYPE.  FOR
NOW...WILL MAKE MENTION OF THE POTENTIAL FOR AN AREA OF FREEZING
RAIN IN THE HAZARDOUS WEATHER OUTLOOK. IF FREEZING RAIN LOOKS TO BE
MORE CERTAIN...WE WILL NEED TO ISSUE A WINTER WEATHER ADVISORY.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...

BIG PICTURE...

TUESDAY STARTS WITH UPPER RIDGES ON EACH COAST AND A DEEP UPPER
TROUGH/CLOSED LOW OVER THE PLAINS. BY WEDNESDAY THE CLOSED LOW
EJECTS NORTHEAST THROUGH LAKE SUPERIOR INTO CANADA. THIS SWEEPS THE
TROUGH AXIS EAST AND PASSES ACROSS NEW ENGLAND CHRISTMAS DAY.
ANOTHER SHORTWAVE MOVES ONSHORE IN THE PACIFIC NORTHWEST WEDNESDAY
AND PHASES WITH A SECOND DROPPING SOUTH FROM NORTHERN CANADA.  THIS
REESTABLISHES THE UPPER TROUGH OVER THE NORTHERN PLAINS/GREAT LAKES
SATURDAY.

CONTOUR HEIGHTS WILL BE ABOVE NORMAL MIDWEEK...TRENDING BELOW NORMAL
OVER THE WEEKEND AS THE SECOND UPPER TROUGH SHIFTS EAST. THIS POINTS
TO A COOLING TREND AFTER CHRISTMAS.

THE GFS AND ECMWF ARE SIMILAR IN HANDLING THE HOLIDAY STORM. THERE
ARE DIFFERENCES BETWEEN THE MODELS IN HANDLING THE SUNDAY SYSTEM. WE
USED A BLEND MOST OF THE LONG TERM PERIOD...BUT MANUALLY ADJUSTED
POPS FOR SUNDAY WITH LOW CONFIDENCE IN MODEL VALUES.

THE DAILIES...

TUESDAY... HIGH PRESSURE OVER THE MARITIMES WITH RIDGING DOWN THE
ATLANTIC COAST. COASTAL LOW PRESSURE WAVE DEVELOPS ALONG STALLED
WARM FRONT AND MOVES NORTH.  AS THE COASTAL LOW MOVES NORTH IT WILL
RUN UP AGAINST THE MARITIME HIGH. THIS WILL INCREASE THE LOW LEVEL
PRESSURE GRADIENT AND INCREASE THE LOW LEVEL SOUTHEAST WINDS.
RESULT...A SOUTHEAST LOW LEVEL JET RUNS OVER THE RIDGING ALONG THE
COASTAL PLAIN INDUCING LOW LEVEL LIFT. THE MOIST LAYER EXPANDS ABOVE
800 MB...NOT DEEP BUT DEEP ENOUGH FOR THE LIFT TO GENERATE LIGHT
PCPN. PTYPE WILL BE RAIN MOST PLACES...BUT THERE COULD BE SPOTS OF
LIGHT FREEZING RAIN IN NORTHWEST MASSACHUSETTS. WE WILL MAINTAIN
CHANCE POPS BUT INCREASE TO AROUND 50 PCT...THE HIGH END OF THE
CHANCE RANGE.

LOW LEVEL SOUTH JET MOVES UP THE COAST TUESDAY NIGHT REACHING THE
COOLER AIR OVER NEW ENGLAND AFTER MIDNIGHT AND BEFORE SUNRISE. THIS
WILL GENERATE ADDITIONAL LIFT AS WELL AS INCREASING AND DEEPENING
MOISTURE. THIS SUGGESTS INCREASING POPS OVERNIGHT.  TEMPERATURES
SHOULD REMAIN ABOVE FREEZING SO PTYPE SHOULD BE RAIN.

WEDNESDAY-THURSDAY... SOUTH 40-50 KNOT LOW LEVEL JET MOVES OVER NEW
ENGLAND WEDNESDAY GENERATING STRONG LIFT AND TRANSPORTING HIGH
VALUES OF PRECIPITABLE WATER INTO THAT LIFT. THE MOISTURE VALUES ARE
MORE THAN 3 STD DEVIATIONS ABOVE NORMAL FOR DECEMBER...AND ACTUALLY
NEAR THE MAXIMUM PREVIOUSLY OBSERVED VALUE. THIS SUGGESTS RAIN WITH
SOME HEAVY DOWNPOURS. COLD FRONT APPROACHES LATE WEDNESDAY NIGHT AND
CROSSES SOUTHERN NEW ENGLAND CHRISTMAS MORNING. THE FRONT WILL HAVE
DYNAMIC SUPPORT FROM A 140-150 KNOT UPPER JET. THE FOREWARD PROGRESS
OF THE FRONT WILL SLOW BECAUSE MOST OF THE MOTION IN THE UPPER JET
WILL BE PARALLEL TO THE FRONT. THIS WILL MEAN CONTINUED RAIN/HEAVY
RAIN THROUGH THE NIGHT INTO THURSDAY MORNING.

THE OBVIOUS CONCERN FOR THIS PERIOD WILL BE FLOODING FROM HEAVY
RAINFALL. RAIN AMOUNTS OF 2 TO 3 INCHES ARE EXPECTED. THIS SHOULD BE
SUFFICIENT FOR AT LEAST URBAN AND POOR DRAINAGE FLOODING. A FLOOD
WATCH MAY BE NEEDED.

A SECOND CONCERN WILL BE WIND. THE LOW LEVEL JET WEDNESDAY WILL BE
SOUTH 40-50 KNOTS...AND INCREASE TO 55-65 KNOTS WEDNESDAY NIGHT.
CONVENTIONAL MIXING WILL NOT BE DEEP...BUT HEAVY DOWNPOURS COULD
CREATE A MOIST ADIABATIC CHANNEL THAT BRINGS DOWN SOME STRONGER WIND
GUSTS. MODEL GRIDS ARE RATHER LIGHT ON WIND GUSTS...15 TO 30 KNOTS.
WE WILL MANUALLY ADJUST THESE VALUES UP TO 25-35 KNOTS OVER LAND AND
A LITTLE STRONGER OVER WATER.

A THIRD CONCERN WILL BE COASTAL FLOODING. MORE DETAILS ON THIS IN
THE TIDE/COASTAL FLOOD SECTION.

WINDS SHIFT TO WEST BEHIND THE FRONT ON CHRISTMAS DAY. THIS WILL
BRING DRIER AIR AND SO END THE RAINFALL. COLD ADVECTION WILL PROMOTE
MIXING TO NEAR 850 MB IN THE AFTERNOON AND TAP 25-35 KNOT WIND
GUSTS...POSSIBLY 40 KNOT GUSTS. A WIND ADVISORY MAY BE NEEDED FOR
THESE WEST WINDS THURSDAY.

FRIDAY THROUGH SUNDAY.... HIGH PRESSURE MOVES OVER THE REGION FRIDAY
BRINGING DRY WEATHER.  SHORTWAVE MOVING THROUGH THE GREAT LAKES
SWINGS A COLD FRONT THROUGH NEW ENGLAND SATURDAY. THE SURFACE
REFLECTION OF THE SHORTWAVE MOVES UP THE ST LAWRENCE VALLEY AND JET
SUPPPORT WILL MOSTLY BE NORTH OF THE BORDER...SO PCPN WILL BE
LIMITED.  QUESTION FOR SUNDAY WILL BE WHETHER A WAVE FORMS ON THE
DEPARTING COLD FRONT...IF SO IT MIGHT BRING PCPN TO NEW ENGLAND. THE
ECMWF THINKS SO BUT THE GFS DOES NOT. WE BROUGHT IN A CHANCE OF RAIN
AND SNOW SHOWERS.

&&

.AVIATION /21Z SUNDAY THROUGH FRIDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH MONDAY NIGHT/...

THROUGH TONIGHT...MODERATE CONFIDENCE. MAINLY MVFR/IFR CONDITIONS
THROUGH TONIGHT. EXCEPTION RIGHT NOW IS THE CAPE AND ISLANDS WHERE
VFR CONDITIONS ARE IN PLACE. BELIEVE CONDITIONS WILL DETERIORATE
LATER TONIGHT THERE. WIDESPREAD LIGHT SNOW SHOWERS ARE AFFECTING
ALL OF SOUTHERN NEW ENGLAND THIS AFTERNOON. EXPECT THIS ACTIVITY
TO BECOME MORE SCATTERED IN NATURE. RAIN SHOWERS ACROSS MOST OF
PLYMOUTH COUNTY AND ONTO THE CAPE/ISLANDS WITH SNOW SHOWERS NORTH
AND WEST.

MONDAY AND MONDAY NIGHT...MODERATE CONFIDENCE. MAINLY MVFR
CONDITIONS CONTINUE IN SCATTERED LIGHT SNOW SHOWERS. LIGHT FZRA
POSSIBLE LATE MONDAY NIGHT ACROSS NW MASSACHUSETTS.

KBOS TERMINAL...MODERATE CONFIDENCE.

KBDL TERMINAL...MODERATE CONFIDENCE.

OUTLOOK...TUESDAY THROUGH FRIDAY...MODERATE CONFIDENCE

TUESDAY...MVFR CIGS AND VSBYS IN LIGHT RAIN.  EAST SOUTHEAST
WINDS...WITH FREQUENT GUSTS TO 25 KNOTS ON THE CAPE AND ISLANDS.

LATE TUESDAY NIGHT-WEDNESDAY-THURSDAY... CONDITIONS LOWERING TO
IFR/LIFR IN RAIN/HEAVY RAIN. SOUTHEAST WINDS GUSTING 25 TO 35 KNOTS
WEDNESDAY AND SOUTH WINDS SIMILAR SPEEDS WEDNESDAY NIGHT...EXCEPT 30
TO 40 KNOTS CAPE COD AND ISLANDS. WINDS AT 2000 FEET MAY REACH 55 TO
65 KNOTS BY WEDNESDAY NIGHT CREATING LOW LEVEL WIND SHEAR. ISOLATED
THUNDERSTORMS WEDNESDAY AFTERNOON AND NIGHT. COLD FRONT SWINGS
THROUGH ON THURSDAY MORNING BRINGING A WIND SHIFT TO WEST WITH GUSTS
30-40 KNOTS.  CONDITIONS IMPROVE TO VFR AFTER THE WIND SHIFT.

FRIDAY...
VFR.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

HIGH PRESSURE ACROSS QUEBEC AND THE MARITIMES WILL RESULT IN
PERSISTENT NORTHEASTERLY TO EASTERLY WINDS ACROSS THE WATERS THROUGH
MONDAY.  THIS WILL RESULT IN BUILDING SEAS ON THE EASTERN WATERS
DESPITE WIND GUSTS UP TO 20 KNOTS.  SEAS BUILD TO AT LEAST 5 FEET ON
THE EASTERN WATERS BY MIDDAY MONDAY.  HAVE ISSUED A SMALL CRAFT
ADVISORY FOR THE EASTERN WATERS BEGINNING MIDDAY MONDAY AND
CONTINUING THROUGH TUESDAY MORNING.  WINDS INCREASE TO NEAR 25 KTS
ON THE SOUTHERN WATERS BY 12Z TUESDAY.

OUTLOOK...TUESDAY THROUGH FRIDAY...MODERATE CONFIDENCE

TUESDAY...EAST WIND GUSTING TO 25 KNOTS...BECOMING SOUTHEAST AT
NIGHT. SEAS 5 TO 7 FEET ON THE EXPOSED WATERS.  A SMALL CRAFT
ADVISORY WILL BE NEEDED.

WEDNESDAY-THURSDAY... SOUTH WINDS WITH FREQUENT GUSTS 35 TO 40 KNOTS
BY WEDNESDAY AFTERNOON AND CONTINUING THROUGH THE NIGHT. WINDS SHIFT
WEST THURSDAY MORNING WITH SIMILAR SPEEDS THROUGH THE AFTERNOON.
SEAS WILL BUILD TO 7 TO 12 FEET ON THE EXPOSED WATERS BY WEDNESDAY
NIGHT AND THURSDAY.  A GALE WARNING MAY BE NEEDED.

FRIDAY...WINDS DIMINISHING TO 25 KNOTS FRIDAY MORNING AND BELOW 25
KNOTS BY AFTERNOON.  SEAS LINGERING AT 5 TO 7 FEET ON THE EXPOSED
WATERS. A SMALL CRAFT ADVISORY MAY BE NEEDED.

&&

.TIDES/COASTAL FLOODING...
HIGH ASTRONOMICAL TIDES WILL OCCUR TUESDAY THROUGH THURSDAY.

TUESDAY...HIGH TIDE AT BOSTON WILL BE 11.6 FT. WINDS WILL BE FROM
THE EAST...SO THERE WILL BE ONSHORE FLOW DURING THIS HIGH TIDE
ALLOWING FOR MINOR SPLASHOVER. IF WINDS INCREASE THEN COULD SEE
SOME POCKETS OF MINOR COASTAL FLOODING.

WEDNESDAY...WINDS SHIFT TO A MORE SOUTHEASTERLY FLOW DURING THE DAY
AND INCREASE QUICKLY AS AN APPROACHING SYSTEM BRINGS PRESSURE
FALLS OF 1 MB/HR. THE WEDNESDAY AFTERNOON HIGH TIDE IN BOSTON IS
11.7 FT AND STRONG SOUTHEASTERLY WINDS WILL BE JUST OFFSHORE.
RIGHT NOW BELIEVE MINOR COASTAL FLOODING IS POSSIBLE ALONG THE
EAST COAST.

WEDNESDAY EVENING...SOUTHERLY WINDS ARE EXPECTED AND ASTRONOMICAL
TIDES INCREASE ALONG THE SOUTH COAST. HIGH TIDE IN PROVIDENCE WILL
BE 5.2 FT. 925 MB LLJ STRENGTHENS TO 55-65 KTS WHICH COULD PUSH A
DECENT SURGE UP ALONG THE SOUTH COAST DURING THE TIME OF HIGH
TIDE. THINKING THAT MINOR COASTAL FLOODING COULD OCCUR BUT CANNOT
RULE OUT MODERATE ALONG THE SOUTH COAST...ESPECIALLY IF LLJ
CONTINUES TO STRENGTHEN.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 4 PM MONDAY TO 7 AM EST TUESDAY FOR
     ANZ250.
     SMALL CRAFT ADVISORY FROM 10 PM MONDAY TO 7 AM EST TUESDAY FOR
     ANZ251-255.
     SMALL CRAFT ADVISORY FROM 1 PM MONDAY TO 7 AM EST TUESDAY FOR
     ANZ254.

&&

$$
SYNOPSIS...WTB/RLG
NEAR TERM...RLG
SHORT TERM...RLG
LONG TERM...WTB
AVIATION...WTB/RLG
MARINE...WTB/RLG
TIDES/COASTAL FLOODING...



000
FXUS61 KBOX 212056
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
356 PM EST SUN DEC 21 2014

.SYNOPSIS...
SCATTERED SNOW/RAIN SHOWERS CONTINUE THROUGH MONDAY. WEAK LOW
PRESSURE WILL PASS SOUTH OF NEW ENGLAND BRINGING ANOTHER PERIOD OF
PRECIPITATION MONDAY NIGHT AND TUESDAY. A MUCH STRONGER STORM
PASSING WEST OF NEW ENGLAND WILL BRING HEAVY RAINFALL... GUSTY
WINDS AND COASTAL FLOODING CONCERNS TO THE REGION WEDNESDAY AND
WEDNESDAY NIGHT. DRY BUT VERY WINDY CONDITIONS FOLLOW FOR
CHRISTMAS DAY. HIGH PRESSURE BRINGS DRY WEATHER FRIDAY. ANOTHER
DEVELOPING SYSTEM MAY BRING RAIN AND SNOW NEXT SUNDAY.

&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
SHORTWAVE RIDGING BUILDS OVER SOUTHERN NEW ENGLAND OVERNIGHT. IN
ADDITION...HIGH PRESSURE IN QUEBEC BUILDS OVER THE REGION AS WELL.
THEREFORE...THERE WILL BE NO FOCUSING MECHANISM FOR PRECIP.
HOWEVER...ONSHORE FLOW AND DECENT MID LEVEL LAPSE RATES WILL ALLOW
FOR A FEW SCATTERED SNOW/RAIN SHOWERS ACROSS THE AREA OVERNIGHT.
EXPECT SNOW SHOWERS TO REMAIN ROUGHLY NORTH AND WEST OF A NEWPORT TO
TAUNTON TO SCITUATE LINE.  ANY ADDITIONAL SNOWFALL WILL AMOUNT TO A
DUSTING TO ABOUT AN INCH. TEMPERATURES WILL FALL INTO THE MID 20S
ACROSS THE NORTHWEST TO THE MID 30S ON THE CAPE AND ISLANDS.

&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/...
MONDAY...CLOUDY...DAMP...AND RAW CONDITIONS WILL CONTINUE THROUGH
THE DAY WITH CONTINUED ONSHORE FLOW AND SCATTERED SNOW/RAIN SHOWERS.

MONDAY NIGHT...WEAK LOW PRESSURE MOVING UP THE COAST TO JUST OFF THE
DELMARVA PENINSULA WILL PRODUCE WARM ADVECTION OVER SOUTHERN NEW
ENGLAND.  THIS IN TURN WILL LIKELY RESULT IN SOME PRECIPITATION
DEVELOPING OVERNIGHT.  HIGH PRESSURE MOVING INTO THE MARITIMES WILL
ALLOW FOR SOME COLD AIR DAMMING...PARTICULARLY INTO INTERIOR
SOUTHERN NEW ENGLAND.  THIS SCENARIO IS A GOOD SET UP FOR SOME
FREEZING RAIN ACROSS THE INTERIOR.  THE MAIN QUESTION IS HOW FAR
NORTH THE WARMER AIR GETS AS THIS WILL DETERMINE PTYPE.  FOR
NOW...WILL MAKE MENTION OF THE POTENTIAL FOR AN AREA OF FREEZING
RAIN IN THE HAZARDOUS WEATHER OUTLOOK. IF FREEZING RAIN LOOKS TO BE
MORE CERTAIN...WE WILL NEED TO ISSUE A WINTER WEATHER ADVISORY.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...

BIG PICTURE...

TUESDAY STARTS WITH UPPER RIDGES ON EACH COAST AND A DEEP UPPER
TROUGH/CLOSED LOW OVER THE PLAINS. BY WEDNESDAY THE CLOSED LOW
EJECTS NORTHEAST THROUGH LAKE SUPERIOR INTO CANADA. THIS SWEEPS THE
TROUGH AXIS EAST AND PASSES ACROSS NEW ENGLAND CHRISTMAS DAY.
ANOTHER SHORTWAVE MOVES ONSHORE IN THE PACIFIC NORTHWEST WEDNESDAY
AND PHASES WITH A SECOND DROPPING SOUTH FROM NORTHERN CANADA.  THIS
REESTABLISHES THE UPPER TROUGH OVER THE NORTHERN PLAINS/GREAT LAKES
SATURDAY.

CONTOUR HEIGHTS WILL BE ABOVE NORMAL MIDWEEK...TRENDING BELOW NORMAL
OVER THE WEEKEND AS THE SECOND UPPER TROUGH SHIFTS EAST. THIS POINTS
TO A COOLING TREND AFTER CHRISTMAS.

THE GFS AND ECMWF ARE SIMILAR IN HANDLING THE HOLIDAY STORM. THERE
ARE DIFFERENCES BETWEEN THE MODELS IN HANDLING THE SUNDAY SYSTEM. WE
USED A BLEND MOST OF THE LONG TERM PERIOD...BUT MANUALLY ADJUSTED
POPS FOR SUNDAY WITH LOW CONFIDENCE IN MODEL VALUES.

THE DAILIES...

TUESDAY... HIGH PRESSURE OVER THE MARITIMES WITH RIDGING DOWN THE
ATLANTIC COAST. COASTAL LOW PRESSURE WAVE DEVELOPS ALONG STALLED
WARM FRONT AND MOVES NORTH.  AS THE COASTAL LOW MOVES NORTH IT WILL
RUN UP AGAINST THE MARITIME HIGH. THIS WILL INCREASE THE LOW LEVEL
PRESSURE GRADIENT AND INCREASE THE LOW LEVEL SOUTHEAST WINDS.
RESULT...A SOUTHEAST LOW LEVEL JET RUNS OVER THE RIDGING ALONG THE
COASTAL PLAIN INDUCING LOW LEVEL LIFT. THE MOIST LAYER EXPANDS ABOVE
800 MB...NOT DEEP BUT DEEP ENOUGH FOR THE LIFT TO GENERATE LIGHT
PCPN. PTYPE WILL BE RAIN MOST PLACES...BUT THERE COULD BE SPOTS OF
LIGHT FREEZING RAIN IN NORTHWEST MASSACHUSETTS. WE WILL MAINTAIN
CHANCE POPS BUT INCREASE TO AROUND 50 PCT...THE HIGH END OF THE
CHANCE RANGE.

LOW LEVEL SOUTH JET MOVES UP THE COAST TUESDAY NIGHT REACHING THE
COOLER AIR OVER NEW ENGLAND AFTER MIDNIGHT AND BEFORE SUNRISE. THIS
WILL GENERATE ADDITIONAL LIFT AS WELL AS INCREASING AND DEEPENING
MOISTURE. THIS SUGGESTS INCREASING POPS OVERNIGHT.  TEMPERATURES
SHOULD REMAIN ABOVE FREEZING SO PTYPE SHOULD BE RAIN.

WEDNESDAY-THURSDAY... SOUTH 40-50 KNOT LOW LEVEL JET MOVES OVER NEW
ENGLAND WEDNESDAY GENERATING STRONG LIFT AND TRANSPORTING HIGH
VALUES OF PRECIPITABLE WATER INTO THAT LIFT. THE MOISTURE VALUES ARE
MORE THAN 3 STD DEVIATIONS ABOVE NORMAL FOR DECEMBER...AND ACTUALLY
NEAR THE MAXIMUM PREVIOUSLY OBSERVED VALUE. THIS SUGGESTS RAIN WITH
SOME HEAVY DOWNPOURS. COLD FRONT APPROACHES LATE WEDNESDAY NIGHT AND
CROSSES SOUTHERN NEW ENGLAND CHRISTMAS MORNING. THE FRONT WILL HAVE
DYNAMIC SUPPORT FROM A 140-150 KNOT UPPER JET. THE FOREWARD PROGRESS
OF THE FRONT WILL SLOW BECAUSE MOST OF THE MOTION IN THE UPPER JET
WILL BE PARALLEL TO THE FRONT. THIS WILL MEAN CONTINUED RAIN/HEAVY
RAIN THROUGH THE NIGHT INTO THURSDAY MORNING.

THE OBVIOUS CONCERN FOR THIS PERIOD WILL BE FLOODING FROM HEAVY
RAINFALL. RAIN AMOUNTS OF 2 TO 3 INCHES ARE EXPECTED. THIS SHOULD BE
SUFFICIENT FOR AT LEAST URBAN AND POOR DRAINAGE FLOODING. A FLOOD
WATCH MAY BE NEEDED.

A SECOND CONCERN WILL BE WIND. THE LOW LEVEL JET WEDNESDAY WILL BE
SOUTH 40-50 KNOTS...AND INCREASE TO 55-65 KNOTS WEDNESDAY NIGHT.
CONVENTIONAL MIXING WILL NOT BE DEEP...BUT HEAVY DOWNPOURS COULD
CREATE A MOIST ADIABATIC CHANNEL THAT BRINGS DOWN SOME STRONGER WIND
GUSTS. MODEL GRIDS ARE RATHER LIGHT ON WIND GUSTS...15 TO 30 KNOTS.
WE WILL MANUALLY ADJUST THESE VALUES UP TO 25-35 KNOTS OVER LAND AND
A LITTLE STRONGER OVER WATER.

A THIRD CONCERN WILL BE COASTAL FLOODING. MORE DETAILS ON THIS IN
THE TIDE/COASTAL FLOOD SECTION.

WINDS SHIFT TO WEST BEHIND THE FRONT ON CHRISTMAS DAY. THIS WILL
BRING DRIER AIR AND SO END THE RAINFALL. COLD ADVECTION WILL PROMOTE
MIXING TO NEAR 850 MB IN THE AFTERNOON AND TAP 25-35 KNOT WIND
GUSTS...POSSIBLY 40 KNOT GUSTS. A WIND ADVISORY MAY BE NEEDED FOR
THESE WEST WINDS THURSDAY.

FRIDAY THROUGH SUNDAY.... HIGH PRESSURE MOVES OVER THE REGION FRIDAY
BRINGING DRY WEATHER.  SHORTWAVE MOVING THROUGH THE GREAT LAKES
SWINGS A COLD FRONT THROUGH NEW ENGLAND SATURDAY. THE SURFACE
REFLECTION OF THE SHORTWAVE MOVES UP THE ST LAWRENCE VALLEY AND JET
SUPPPORT WILL MOSTLY BE NORTH OF THE BORDER...SO PCPN WILL BE
LIMITED.  QUESTION FOR SUNDAY WILL BE WHETHER A WAVE FORMS ON THE
DEPARTING COLD FRONT...IF SO IT MIGHT BRING PCPN TO NEW ENGLAND. THE
ECMWF THINKS SO BUT THE GFS DOES NOT. WE BROUGHT IN A CHANCE OF RAIN
AND SNOW SHOWERS.

&&

.AVIATION /21Z SUNDAY THROUGH FRIDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH MONDAY NIGHT/...

THROUGH TONIGHT...MODERATE CONFIDENCE. MAINLY MVFR/IFR CONDITIONS
THROUGH TONIGHT. EXCEPTION RIGHT NOW IS THE CAPE AND ISLANDS WHERE
VFR CONDITIONS ARE IN PLACE. BELIEVE CONDITIONS WILL DETERIORATE
LATER TONIGHT THERE. WIDESPREAD LIGHT SNOW SHOWERS ARE AFFECTING
ALL OF SOUTHERN NEW ENGLAND THIS AFTERNOON. EXPECT THIS ACTIVITY
TO BECOME MORE SCATTERED IN NATURE. RAIN SHOWERS ACROSS MOST OF
PLYMOUTH COUNTY AND ONTO THE CAPE/ISLANDS WITH SNOW SHOWERS NORTH
AND WEST.

MONDAY AND MONDAY NIGHT...MODERATE CONFIDENCE. MAINLY MVFR
CONDITIONS CONTINUE IN SCATTERED LIGHT SNOW SHOWERS. LIGHT FZRA
POSSIBLE LATE MONDAY NIGHT ACROSS NW MASSACHUSETTS.

KBOS TERMINAL...MODERATE CONFIDENCE.

KBDL TERMINAL...MODERATE CONFIDENCE.

OUTLOOK...TUESDAY THROUGH FRIDAY...MODERATE CONFIDENCE

TUESDAY...MVFR CIGS AND VSBYS IN LIGHT RAIN.  EAST SOUTHEAST
WINDS...WITH FREQUENT GUSTS TO 25 KNOTS ON THE CAPE AND ISLANDS.

LATE TUESDAY NIGHT-WEDNESDAY-THURSDAY... CONDITIONS LOWERING TO
IFR/LIFR IN RAIN/HEAVY RAIN. SOUTHEAST WINDS GUSTING 25 TO 35 KNOTS
WEDNESDAY AND SOUTH WINDS SIMILAR SPEEDS WEDNESDAY NIGHT...EXCEPT 30
TO 40 KNOTS CAPE COD AND ISLANDS. WINDS AT 2000 FEET MAY REACH 55 TO
65 KNOTS BY WEDNESDAY NIGHT CREATING LOW LEVEL WIND SHEAR. ISOLATED
THUNDERSTORMS WEDNESDAY AFTERNOON AND NIGHT. COLD FRONT SWINGS
THROUGH ON THURSDAY MORNING BRINGING A WIND SHIFT TO WEST WITH GUSTS
30-40 KNOTS.  CONDITIONS IMPROVE TO VFR AFTER THE WIND SHIFT.

FRIDAY...
VFR.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

HIGH PRESSURE ACROSS QUEBEC AND THE MARITIMES WILL RESULT IN
PERSISTENT NORTHEASTERLY TO EASTERLY WINDS ACROSS THE WATERS THROUGH
MONDAY.  THIS WILL RESULT IN BUILDING SEAS ON THE EASTERN WATERS
DESPITE WIND GUSTS UP TO 20 KNOTS.  SEAS BUILD TO AT LEAST 5 FEET ON
THE EASTERN WATERS BY MIDDAY MONDAY.  HAVE ISSUED A SMALL CRAFT
ADVISORY FOR THE EASTERN WATERS BEGINNING MIDDAY MONDAY AND
CONTINUING THROUGH TUESDAY MORNING.  WINDS INCREASE TO NEAR 25 KTS
ON THE SOUTHERN WATERS BY 12Z TUESDAY.

OUTLOOK...TUESDAY THROUGH FRIDAY...MODERATE CONFIDENCE

TUESDAY...EAST WIND GUSTING TO 25 KNOTS...BECOMING SOUTHEAST AT
NIGHT. SEAS 5 TO 7 FEET ON THE EXPOSED WATERS.  A SMALL CRAFT
ADVISORY WILL BE NEEDED.

WEDNESDAY-THURSDAY... SOUTH WINDS WITH FREQUENT GUSTS 35 TO 40 KNOTS
BY WEDNESDAY AFTERNOON AND CONTINUING THROUGH THE NIGHT. WINDS SHIFT
WEST THURSDAY MORNING WITH SIMILAR SPEEDS THROUGH THE AFTERNOON.
SEAS WILL BUILD TO 7 TO 12 FEET ON THE EXPOSED WATERS BY WEDNESDAY
NIGHT AND THURSDAY.  A GALE WARNING MAY BE NEEDED.

FRIDAY...WINDS DIMINISHING TO 25 KNOTS FRIDAY MORNING AND BELOW 25
KNOTS BY AFTERNOON.  SEAS LINGERING AT 5 TO 7 FEET ON THE EXPOSED
WATERS. A SMALL CRAFT ADVISORY MAY BE NEEDED.

&&

.TIDES/COASTAL FLOODING...
HIGH ASTRONOMICAL TIDES WILL OCCUR TUESDAY THROUGH THURSDAY.

TUESDAY...HIGH TIDE AT BOSTON WILL BE 11.6 FT. WINDS WILL BE FROM
THE EAST...SO THERE WILL BE ONSHORE FLOW DURING THIS HIGH TIDE
ALLOWING FOR MINOR SPLASHOVER. IF WINDS INCREASE THEN COULD SEE
SOME POCKETS OF MINOR COASTAL FLOODING.

WEDNESDAY...WINDS SHIFT TO A MORE SOUTHEASTERLY FLOW DURING THE DAY
AND INCREASE QUICKLY AS AN APPROACHING SYSTEM BRINGS PRESSURE
FALLS OF 1 MB/HR. THE WEDNESDAY AFTERNOON HIGH TIDE IN BOSTON IS
11.7 FT AND STRONG SOUTHEASTERLY WINDS WILL BE JUST OFFSHORE.
RIGHT NOW BELIEVE MINOR COASTAL FLOODING IS POSSIBLE ALONG THE
EAST COAST.

WEDNESDAY EVENING...SOUTHERLY WINDS ARE EXPECTED AND ASTRONOMICAL
TIDES INCREASE ALONG THE SOUTH COAST. HIGH TIDE IN PROVIDENCE WILL
BE 5.2 FT. 925 MB LLJ STRENGTHENS TO 55-65 KTS WHICH COULD PUSH A
DECENT SURGE UP ALONG THE SOUTH COAST DURING THE TIME OF HIGH
TIDE. THINKING THAT MINOR COASTAL FLOODING COULD OCCUR BUT CANNOT
RULE OUT MODERATE ALONG THE SOUTH COAST...ESPECIALLY IF LLJ
CONTINUES TO STRENGTHEN.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 4 PM MONDAY TO 7 AM EST TUESDAY FOR
     ANZ250.
     SMALL CRAFT ADVISORY FROM 10 PM MONDAY TO 7 AM EST TUESDAY FOR
     ANZ251-255.
     SMALL CRAFT ADVISORY FROM 1 PM MONDAY TO 7 AM EST TUESDAY FOR
     ANZ254.

&&

$$
SYNOPSIS...WTB/RLG
NEAR TERM...RLG
SHORT TERM...RLG
LONG TERM...WTB
AVIATION...WTB/RLG
MARINE...WTB/RLG
TIDES/COASTAL FLOODING...




000
FXUS61 KBOX 212024
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
324 PM EST SUN DEC 21 2014

.SYNOPSIS...
SCATTERED SNOW/RAIN SHOWERS CONTINUE THROUGH THIS AFTERNOON. WEAK
LOW PRESSURE WILL PASS SOUTH OF NEW ENGLAND BRINGING ANOTHER
PERIOD OF PRECIPITATION MONDAY NIGHT AND TUESDAY. A MUCH STRONGER
STORM PASSING WEST OF NEW ENGLAND WILL BRING HEAVY RAINFALL...
GUSTY WINDS AND COASTAL FLOODING CONCERNS TO THE REGION WEDNESDAY
AND WEDNESDAY NIGHT. DRY BUT VERY WINDY CONDITIONS FOLLOW FOR
CHRISTMAS DAY.

&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
SHORTWAVE RIDGING BUILDS OVER SOUTHERN NEW ENGLAND OVERNIGHT. IN
ADDITION...HIGH PRESSURE IN QUEBEC BUILDS OVER THE REGION AS WELL.
THEREFORE...THERE WILL BE NO FOCUSING MECHANISM FOR PRECIP.
HOWEVER...ONSHORE FLOW AND DECENT MID LEVEL LAPSE RATES WILL ALLOW
FOR A FEW SCATTERED SNOW/RAIN SHOWERS ACROSS THE AREA OVERNIGHT.
EXPECT SNOW SHOWERS TO REMAIN ROUGHLY NORTH AND WEST OF A NEWPORT TO
TAUNTON TO SCITUATE LINE.  ANY ADDITIONAL SNOWFALL WILL AMOUNT TO A
DUSTING TO ABOUT AN INCH. TEMPERATURES WILL FALL INTO THE MID 20S
ACROSS THE NORTHWEST TO THE MID 30S ON THE CAPE AND ISLANDS.

&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/...
MONDAY...CLOUDY...DAMP...AND RAW CONDITIONS WILL CONTINUE THROUGH
THE DAY WITH CONTINUED ONSHORE FLOW AND SCATTERED SNOW/RAIN SHOWERS.

MONDAY NIGHT...WEAK LOW PRESSURE MOVING UP THE COAST TO JUST OFF THE
DELMARVA PENINSULA WILL PRODUCE WARM ADVECTION OVER SOUTHERN NEW
ENGLAND.  THIS IN TURN WILL LIKELY RESULT IN SOME PRECIPITATION
DEVELOPING OVERNIGHT.  HIGH PRESSURE MOVING INTO THE MARITIMES WILL
ALLOW FOR SOME COLD AIR DAMMING...PARTICULARLY INTO INTERIOR
SOUTHERN NEW ENGLAND.  THIS SCENARIO IS A GOOD SET UP FOR SOME
FREEZING RAIN ACROSS THE INTERIOR.  THE MAIN QUESTION IS HOW FAR
NORTH THE WARMER AIR GETS AS THIS WILL DETERMINE PTYPE.  FOR
NOW...WILL MAKE MENTION OF THE POTENTIAL FOR AN AREA OF FREEZING
RAIN IN THE HAZARDOUS WEATHER OUTLOOK. IF FREEZING RAIN LOOKS TO BE
MORE CERTAIN...WE WILL NEED TO ISSUE A WINTER WEATHER ADVISORY.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
HIGHLIGHTS...

* WEAK SHORTWAVE ON MON NIGHT/TUESDAY COULD BRING WINTRY
  MIX/FREEZING RAIN TO THE INTERIOR
* ANOMALOUS SYSTEM ACROSS THE GREAT LAKES WILL BRING HEAVY
  RAIN...GUSTY WINDS AND COASTAL FLOODING CONCERNS AROUND CHRISTMAS
  EVE
* BLUSTERY BUT AIRMASS WILL BE DRYING OUT ON CHRISTMAS DAY

OVERVIEW...

THE MODELS AND ENSEMBLES OFFER A REASONABLY SIMILAR AND PREDICTABLE
LARGER SCALE MID TO UPPER LEVEL PATTERN EVOLUTION FOR MUCH OF THE
UPCOMING WEEK. THIS ACTIVE FLOW REGIME DEVELOPS SEVERAL MID-UPPER
LEVEL TROUGH AND ASSOCIATED/UNSETTLING LEAD SURFACE LOW/FRONTAL
SYSTEMS AND PCPN SWATHS PROGRESS STEADILY ACROSS THE LOWER 48. THE
FIRST AMPLIFIED/DEEP LEAD SYSTEM WORKS ACROSS THE ERN/NERN US INTO
ERN CANADA CHRISTMAS EVE INTO CHRISTMAS ALLOWING FOR A MOIST/WARMED
AIRMASS IN ADVANCE OF FRONTAL APPROACH WITH HEAVIEST LEAD QPF
POTENTIAL OVER NEW ENGLAND. BIGGEST QUESTION IS THE EVOLUTION OF THE
SECONDARY LOW PRESSURE SYSTEM. 00Z GUIDANCE HAS BACKED OFF ON THE
STRENGTH OF THE LOW AND IS HAVING ISSUES ON HOW TO HANDLE ITS
EVOLUTION. THE EC AND GFS HAVE SLOWED DOWN THE SYSTEM SLIGHTLY WITH
THE EC HAVING MORE OF A NEGATIVE TROUGH VS THE GFS. BELIEVE THE
UKMET IS A GOOD COMPROMISE AT IS WAS THE FIRST DETERMINISTIC
GUIDANCE ON TAMPERING DOWN THE FIRST MAIN LOW...WHILE THE CMC IS OUT
TO LUNCH. REGARDLESS THIS IS A VERY ANOMALOUS SYSTEM THAT IS ABOUT 4
STANDARD DEVIATIONS AWAY.

A SECONDARY SYSTEM DEEPENS ACROSS THE FOUR CORNERS ON FRIDAY AND
WITH THE STUBBORN TROUGH OVER THE CENTRAL U.S...IT WILL PUSH A
SYSTEM TOWARDS SOUTHERN NEW ENGLAND BY SUNDAY. THIS SYSTEM MAY
SUPPORT A MODEST SWATH OF OVERRUNNING SNOW OVER SOUTHERN NEW
ENGLAND.

DETAILS...

TUESDAY...MODERATE CONFIDENCE.

A WEAK WAVE OF LOW PRESSURE DEVELOPS ALONG THE SOUTHEAST COAST
MONDAY...AND WILL BE ON A DEVELOPING WARM FRONTAL BOUNDARY. THIS LOW
REMAINS WEAK AS THE WARM FRONT MOVES SLOWLY NORTH MONDAY NIGHT INTO
TUESDAY. APPEARS THAT THERE IS DECENT WARM ADVECTION AHEAD OF THIS
WAVE. SEVERAL HI-RES GUIDANCE MODELS SHOW THAT THERE IS THE
POTENTIAL FOR COLD AIR DAMMING ACROSS THE INTERIOR INTO TUESDAY.
BIGGEST QUESTION WILL BE IS THERE ENOUGH MOISTURE FOR PRECIP DURING
THIS TIME FRAME. DUE TO A STRENGTHENING LLJ PROVIDING A GOOD SOURCE OF
LIFT ANTICIPATE PRECIP TO DEVELOP AND OVERSPREAD ACROSS SOUTHERN NEW
ENGLAND. IF THIS PLAYS OUT WITH COLD AIR DAMMING AND WARM AIR
ADVECTION...THEN WE COULD SEE FREEZING RAIN/DRIZZLE ACROSS THE I-91
CORRIDOR LATE MONDAY INTO TUESDAY MORNING. DURING THE DAY ON
TUESDAY...GOOD AMOUNT OF WARM AIR WILL PUSH SURFACE TEMPS ABOVE
FREEZING BY THE LATE MORNING ALLOWING FOR ANY PRECIP TO BE MORE OF
THE LIQUID VARIETY AHEAD OF THE CHRISTMAS EVE STORM. HOWEVER
GUIDANCE IS ALWAYS TOO FAST IN SCOURING TEMPS OUT ESP ACROSS THE CT
VALLEY SO WE WILL NEED TO MONITOR THIS CLOSELY...ESP DUE TO LIGHT
WINDS AND THE HIGH IN EASTERN CANADA. A WINTER WX ADVISORY MAY BE
NEEDED FOR THE LIGHT ICING POTENTIAL.

WE COULD ALSO SEE SOME MINOR COASTAL FLOODING CONCERNS ON TUESDAY. SEE
BELOW FOR MORE DETAILS.

WEDNESDAY INTO THURSDAY...HIGH CONFIDENCE IN SYSTEM LOW CONFIDENCE
ON DETAILS.

ANOMALOUS SYSTEM WILL STRENGTHEN OVER THE GREAT LAKES TUESDAY INTO
WEDNESDAY. A SECONDARY SHORTWAVE WILL ROUND THE DEEP TROUGH AND
DEVELOP A SECONDARY LOW PRESSURE ALONG THE COLD FRONT. THIS
SECONDARY LOW WILL STRENGTHEN AND PASS WEST OF SOUTHERN NEW ENGLAND.
THIS SYSTEM WILL CONTINUE TO DEEPEN AS IT MOVES TOWARDS EASTERN
CANADA SWINGING A COLD FRONT ACROSS THE NORTHEAST.

STRONG SOUTHERLY JET OUT AHEAD OF THE FRONT WITH A GULF MOISTURE
CONNECTION WILL IMPACT SOUTHERN NEW ENGLAND ON CHRISTMAS EVE. THIS
STRONG JET WILL YIELD FOR PCPN IN THE LIQUID VARIETY.  PW ANOMALIES
ARE BETWEEN +4 TO +5 STANDARD DEVIATIONS ABOVE NORMAL WHICH IS QUITE
ANOMALOUS FOR THIS TIME OF YEAR. IN FACT CURRENT PWATS ARE PROGGED
ABOVE 1.6 INCHES WITH MODEL QPF OVER 2 INCHES...AT THE VERY LEAST
COULD SEE URBAN AND POOR DRAINAGE FLOODING. LATEST EC EVEN SHOWS
OVER 2.5 INCHES OF QPF...AND WITH THE TROPICAL CONNECTION AND STRONG
SOUTHERLY FLOW COULD SEE HIGHER AMOUNTS DUE TO TOPOGRAPHY
ENHANCEMENTS. RAINFALL RECORDS MAY FALL IF EVERYTHING FALLS INTO
PLACE.

AHEAD OF THE FRONT...SOUTHERN NEW ENGLAND WILL WARM SECTOR WED INTO
THUR MORNING ALLOWING FOR TEMPERATURES TO BE WELL ABOVE AVERAGE. IN
FACT WE MAY BE CLOSE AT BREAKING RECORD HIGH TEMPS IF TEMPS WARM TO
60F OR ABOVE ON CHRISTMAS EVE. SINCE WE WILL BE IN THE WARM
SECTOR...AND SHOWALTERS CLOSE TO ZERO...ISOLATED THUNDER IS STILL
POSSIBLE.

STRONG LOW LEVEL WINDS WILL ALSO BE A CONCERN ESPECIALLY WEDNESDAY
NIGHT. THE ECMWF SHOWS EAST-SOUTHEAST WINDS 30-40 KNOTS ON WEDNESDAY
INCREASING TO 60-75 KNOTS BY WEDNESDAY NIGHT. STRONG DOWNPOURS MAY
OVERCOME THE LOW LEVEL INVERSION AND BRING STRONG GUSTS OF AT LEAST
30-40 KNOTS ESPECIALLY ALONG THE SOUTH COAST. A WIND ADVISORY MAY BE
NEEDED IN SOME AREAS.

CHRISTMAS DAY...MODERATE CONFIDENCE.

AS THE COLD FRONT PASSES THROUGH EARLY CHRISTMAS DAY...THE WEST
WINDS WILL HELP DRY THE AIRMASS ALLOWING FOR PARTLY SUNNY SKIES.
STRONG CAA ON THURSDAY WILL ALLOW DESCENT MIXING. WINDS IN THE SFC-
850 MB LAYER WILL BE 30-40 KNOTS AND POSSIBLY A LITTLE
HIGHER...WHICH WOULD REQUIRE A WIND ADVISORY FOR MUCH OF THE AREA.

FRIDAY-SUNDAY...LOWER CONFIDENCE

WEAK HIGH PRESSURE BUILDS OVER THE AREA FRIDAY INTO SATURDAY. THE
NEXT SHORTWAVE APPROACHES LATE SATURDAY INTO SUNDAY AND SHOULD BRING
INCREASING CLOUDS FROM WEST TO EAST ALONG WITH A CHANCE OF RAIN OR
SNOW SHOWERS MAINLY IN THE AFTERNOON AND AT NIGHT.

&&

.AVIATION /20Z SUNDAY THROUGH FRIDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH MONDAY NIGHT/...

THROUGH TONIGHT...MODERATE CONFIDENCE. MAINLY MVFR/IFR CONDITIONS
THROUGH TONIGHT. EXCEPTION RIGHT NOW IS THE CAPE AND ISLANDS WHERE
VFR CONDITIONS ARE IN PLACE. BELIEVE CONDITIONS WILL DETERIORATE
LATER TONIGHT THERE. WIDESPREAD LIGHT SNOW SHOWERS ARE AFFECTING
ALL OF SOUTHERN NEW ENGLAND THIS AFTERNOON. EXPECT THIS ACTIVITY
TO BECOME MORE SCATTERED IN NATURE. RAIN SHOWERS ACROSS MOST OF
PLYMOUTH COUNTY AND ONTO THE CAPE/ISLANDS WITH SNOW SHOWERS NORTH
AND WEST.

MONDAY AND MONDAY NIGHT...MODERATE CONFIDENCE. MAINLY MVFR
CONDITIONS CONTINUE IN SCATTERED LIGHT SNOW SHOWERS. LIGHT FZRA
POSSIBLE LATE MONDAY NIGHT ACROSS NW MASSACHUSETTS.

KBOS TERMINAL...MODERATE CONFIDENCE.

KBDL TERMINAL...MODERATE CONFIDENCE.

OUTLOOK...MONDAY THROUGH THURSDAY...MODERATE CONFIDENCE.

MONDAY...MVFR CIGS CONTINUE IN RI/EASTERN MASS IN MARINE EAST FLOW.
VFR IN THE WEST.

TUESDAY...VFR WITH SCATTERED MVFR IN ANY RAIN/SNOW SHOWERS.

WEDNESDAY...CONDITIONS LOWERING TO IFR IN RAIN/HEAVY RAIN. ISOLATED
THUNDERSTORMS POSSIBLE ESPECIALLY WEDNESDAY NIGHT. EAST-SOUTHEAST
SURFACE WINDS MAY GUST TO 35-45 KNOTS. WINDS AT 2000 FEET AGL WILL
REACH 50-60 KNOTS WEDNESDAY AFTERNOON AND EARLY NIGHT CREATING LOW
LEVEL WIND SHEAR CONCERNS.

CHRISTMAS DAY...WEST WIND GUSTING 30-40 KNOTS. CONDITIONS IMPROVING
TO VFR AS THE WIND BRINGS IN COOLER DRIER AIR.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

HIGH PRESSURE ACROSS QUEBEC AND THE MARITIMES WILL RESULT IN
PERSISTENT NORTHEASTERLY TO EASTERLY WINDS ACROSS THE WATERS THROUGH
MONDAY.  THIS WILL RESULT IN BUILDING SEAS ON THE EASTERN WATERS
DESPITE WIND GUSTS UP TO 20 KNOTS.  SEAS BUILD TO AT LEAST 5 FEET ON
THE EASTERN WATERS BY MIDDAY MONDAY.  HAVE ISSUED A SMALL CRAFT
ADVISORY FOR THE EASTERN WATERS BEGINNING MIDDAY MONDAY AND
CONTINUING THROUGH TUESDAY MORNING.  WINDS INCREASE TO NEAR 25 KTS
ON THE SOUTHERN WATERS BY 12Z TUESDAY.

OUTLOOK...TUESDAY THROUGH FRIDAY...MODERATE CONFIDENCE

MONDAY...EAST TO NORTHEAST WINDS GUSTING AROUND 15 KNOTS OR LESS.
SEAS WILL HOLD AROUND 3-4 FEET...MAY INCREASE TO 5FT IN NORTHEAST
FLOW AS GUIDANCE MAY BE UNDERDONE.

TUESDAY... INCREASING EAST WINDS WITH FREQUENT GUSTS 25 TO 30 KNOTS.
SEAS WILL BUILD TO 5-6 FEET ON THE EXPOSED WATERS.  A SMALL CRAFT
ADVISORY MAY BE NEEDED.

WEDNESDAY...RAIN WILL BE HEAVY AT TIMES PRODUCING POOR VISIBILITY.
INCREASING SOUTHEAST WINDS 20-25 SUSTAINED AND 40 KNOT GUSTS.  WINDS
SHOULD SHIFT TO SOUTH WEDNESDAY NIGHT AND SOUTHWEST TOWARD THURSDAY
MORNING. RAIN WILL TAPER OFF WITH THE WIND SHIFT TO SOUTHWEST. SEAS
WILL CONTINUE TO BUILD WITH 7-11 FEET HEIGHTS ON THE EXPOSED WATERS.
A GALE WARNING WILL BE NEEDED...WITH A LOW PROB OF A FEW STORM FORCE
GUSTS ACROSS THE EASTERN OUTER WATERS.

CHRISTMAS DAY... WEST SOUTHWEST WINDS WILL CONTINUE TO GUST 35-40
KNOTS...SO A CONTINUED GALE WARNING MAY BE NEEDED. SEAS OF 7-15 FEET
ARE POSSIBLE ON THE EXPOSED WATERS...AND 5 FEET IS POSSIBLE ON SOME
OF THE NEARSHORE WATERS.

&&

.TIDES/COASTAL FLOODING...
HIGH ASTRONOMICAL TIDES WILL OCCUR TUESDAY THROUGH THURSDAY.

TUESDAY...HIGH TIDE AT BOSTON WILL BE 11.6 FT. THERE WILL BE ONSHORE
FLOW DURING THIS HIGH TIDE ALLOWING FOR MINOR SPLASHOVER. IF WINDS
INCREASE THEN COULD SEE SOME POCKETS OF MINOR COASTAL FLOODING.

WEDNESDAY...WINDS SHIFT TO A MORE SOUTHEASTERLY FLOW DURING THE DAY
AND INCREASE QUICKLY AS AN APPROACHING SYSTEM BRINGS DECENT PRESSURE
FALLS. THE WEDNESDAY AFTERNOON HIGH TIDE IN BOSTON IS 11.7 FT AND
STRONG SOUTHEASTERLY WINDS WILL BE JUST OFFSHORE. RIGHT NOW BELIEVE
MINOR COASTAL FLOODING IS POSSIBLE ALONG THE EAST COAST.

WEDNESDAY EVENING...SOUTHERLY WINDS ARE EXPECTED AND ASTRONOMICAL
TIDES INCREASE ALONG THE SOUTH COAST. HIGH TIDE IN PROVIDENCE WILL
BE 5.2 FT. 925 MB LLJ STRENGTHENS TO 50-60 KTS WHICH COULD PUSH A
DECENT SURGE UP ALONG THE SOUTH COAST DURING THE TIME OF HIGH TIDE.
THINKING THAT MINOR COASTAL FLOODING COULD OCCUR BUT CANNOT RULE OUT
MODERATE ALONG THE SOUTH COAST...ESPECIALLY IF LLJ CONTINUES TO
STRENGTHEN.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...DUNTEN/RLG
NEAR TERM...RLG
SHORT TERM...RLG
LONG TERM...DUNTEN
AVIATION...DUNTEN/RLG
MARINE...DUNTEN/RLG
TIDES/COASTAL FLOODING...



000
FXUS61 KBOX 212024
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
324 PM EST SUN DEC 21 2014

.SYNOPSIS...
SCATTERED SNOW/RAIN SHOWERS CONTINUE THROUGH THIS AFTERNOON. WEAK
LOW PRESSURE WILL PASS SOUTH OF NEW ENGLAND BRINGING ANOTHER
PERIOD OF PRECIPITATION MONDAY NIGHT AND TUESDAY. A MUCH STRONGER
STORM PASSING WEST OF NEW ENGLAND WILL BRING HEAVY RAINFALL...
GUSTY WINDS AND COASTAL FLOODING CONCERNS TO THE REGION WEDNESDAY
AND WEDNESDAY NIGHT. DRY BUT VERY WINDY CONDITIONS FOLLOW FOR
CHRISTMAS DAY.

&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
SHORTWAVE RIDGING BUILDS OVER SOUTHERN NEW ENGLAND OVERNIGHT. IN
ADDITION...HIGH PRESSURE IN QUEBEC BUILDS OVER THE REGION AS WELL.
THEREFORE...THERE WILL BE NO FOCUSING MECHANISM FOR PRECIP.
HOWEVER...ONSHORE FLOW AND DECENT MID LEVEL LAPSE RATES WILL ALLOW
FOR A FEW SCATTERED SNOW/RAIN SHOWERS ACROSS THE AREA OVERNIGHT.
EXPECT SNOW SHOWERS TO REMAIN ROUGHLY NORTH AND WEST OF A NEWPORT TO
TAUNTON TO SCITUATE LINE.  ANY ADDITIONAL SNOWFALL WILL AMOUNT TO A
DUSTING TO ABOUT AN INCH. TEMPERATURES WILL FALL INTO THE MID 20S
ACROSS THE NORTHWEST TO THE MID 30S ON THE CAPE AND ISLANDS.

&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/...
MONDAY...CLOUDY...DAMP...AND RAW CONDITIONS WILL CONTINUE THROUGH
THE DAY WITH CONTINUED ONSHORE FLOW AND SCATTERED SNOW/RAIN SHOWERS.

MONDAY NIGHT...WEAK LOW PRESSURE MOVING UP THE COAST TO JUST OFF THE
DELMARVA PENINSULA WILL PRODUCE WARM ADVECTION OVER SOUTHERN NEW
ENGLAND.  THIS IN TURN WILL LIKELY RESULT IN SOME PRECIPITATION
DEVELOPING OVERNIGHT.  HIGH PRESSURE MOVING INTO THE MARITIMES WILL
ALLOW FOR SOME COLD AIR DAMMING...PARTICULARLY INTO INTERIOR
SOUTHERN NEW ENGLAND.  THIS SCENARIO IS A GOOD SET UP FOR SOME
FREEZING RAIN ACROSS THE INTERIOR.  THE MAIN QUESTION IS HOW FAR
NORTH THE WARMER AIR GETS AS THIS WILL DETERMINE PTYPE.  FOR
NOW...WILL MAKE MENTION OF THE POTENTIAL FOR AN AREA OF FREEZING
RAIN IN THE HAZARDOUS WEATHER OUTLOOK. IF FREEZING RAIN LOOKS TO BE
MORE CERTAIN...WE WILL NEED TO ISSUE A WINTER WEATHER ADVISORY.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
HIGHLIGHTS...

* WEAK SHORTWAVE ON MON NIGHT/TUESDAY COULD BRING WINTRY
  MIX/FREEZING RAIN TO THE INTERIOR
* ANOMALOUS SYSTEM ACROSS THE GREAT LAKES WILL BRING HEAVY
  RAIN...GUSTY WINDS AND COASTAL FLOODING CONCERNS AROUND CHRISTMAS
  EVE
* BLUSTERY BUT AIRMASS WILL BE DRYING OUT ON CHRISTMAS DAY

OVERVIEW...

THE MODELS AND ENSEMBLES OFFER A REASONABLY SIMILAR AND PREDICTABLE
LARGER SCALE MID TO UPPER LEVEL PATTERN EVOLUTION FOR MUCH OF THE
UPCOMING WEEK. THIS ACTIVE FLOW REGIME DEVELOPS SEVERAL MID-UPPER
LEVEL TROUGH AND ASSOCIATED/UNSETTLING LEAD SURFACE LOW/FRONTAL
SYSTEMS AND PCPN SWATHS PROGRESS STEADILY ACROSS THE LOWER 48. THE
FIRST AMPLIFIED/DEEP LEAD SYSTEM WORKS ACROSS THE ERN/NERN US INTO
ERN CANADA CHRISTMAS EVE INTO CHRISTMAS ALLOWING FOR A MOIST/WARMED
AIRMASS IN ADVANCE OF FRONTAL APPROACH WITH HEAVIEST LEAD QPF
POTENTIAL OVER NEW ENGLAND. BIGGEST QUESTION IS THE EVOLUTION OF THE
SECONDARY LOW PRESSURE SYSTEM. 00Z GUIDANCE HAS BACKED OFF ON THE
STRENGTH OF THE LOW AND IS HAVING ISSUES ON HOW TO HANDLE ITS
EVOLUTION. THE EC AND GFS HAVE SLOWED DOWN THE SYSTEM SLIGHTLY WITH
THE EC HAVING MORE OF A NEGATIVE TROUGH VS THE GFS. BELIEVE THE
UKMET IS A GOOD COMPROMISE AT IS WAS THE FIRST DETERMINISTIC
GUIDANCE ON TAMPERING DOWN THE FIRST MAIN LOW...WHILE THE CMC IS OUT
TO LUNCH. REGARDLESS THIS IS A VERY ANOMALOUS SYSTEM THAT IS ABOUT 4
STANDARD DEVIATIONS AWAY.

A SECONDARY SYSTEM DEEPENS ACROSS THE FOUR CORNERS ON FRIDAY AND
WITH THE STUBBORN TROUGH OVER THE CENTRAL U.S...IT WILL PUSH A
SYSTEM TOWARDS SOUTHERN NEW ENGLAND BY SUNDAY. THIS SYSTEM MAY
SUPPORT A MODEST SWATH OF OVERRUNNING SNOW OVER SOUTHERN NEW
ENGLAND.

DETAILS...

TUESDAY...MODERATE CONFIDENCE.

A WEAK WAVE OF LOW PRESSURE DEVELOPS ALONG THE SOUTHEAST COAST
MONDAY...AND WILL BE ON A DEVELOPING WARM FRONTAL BOUNDARY. THIS LOW
REMAINS WEAK AS THE WARM FRONT MOVES SLOWLY NORTH MONDAY NIGHT INTO
TUESDAY. APPEARS THAT THERE IS DECENT WARM ADVECTION AHEAD OF THIS
WAVE. SEVERAL HI-RES GUIDANCE MODELS SHOW THAT THERE IS THE
POTENTIAL FOR COLD AIR DAMMING ACROSS THE INTERIOR INTO TUESDAY.
BIGGEST QUESTION WILL BE IS THERE ENOUGH MOISTURE FOR PRECIP DURING
THIS TIME FRAME. DUE TO A STRENGTHENING LLJ PROVIDING A GOOD SOURCE OF
LIFT ANTICIPATE PRECIP TO DEVELOP AND OVERSPREAD ACROSS SOUTHERN NEW
ENGLAND. IF THIS PLAYS OUT WITH COLD AIR DAMMING AND WARM AIR
ADVECTION...THEN WE COULD SEE FREEZING RAIN/DRIZZLE ACROSS THE I-91
CORRIDOR LATE MONDAY INTO TUESDAY MORNING. DURING THE DAY ON
TUESDAY...GOOD AMOUNT OF WARM AIR WILL PUSH SURFACE TEMPS ABOVE
FREEZING BY THE LATE MORNING ALLOWING FOR ANY PRECIP TO BE MORE OF
THE LIQUID VARIETY AHEAD OF THE CHRISTMAS EVE STORM. HOWEVER
GUIDANCE IS ALWAYS TOO FAST IN SCOURING TEMPS OUT ESP ACROSS THE CT
VALLEY SO WE WILL NEED TO MONITOR THIS CLOSELY...ESP DUE TO LIGHT
WINDS AND THE HIGH IN EASTERN CANADA. A WINTER WX ADVISORY MAY BE
NEEDED FOR THE LIGHT ICING POTENTIAL.

WE COULD ALSO SEE SOME MINOR COASTAL FLOODING CONCERNS ON TUESDAY. SEE
BELOW FOR MORE DETAILS.

WEDNESDAY INTO THURSDAY...HIGH CONFIDENCE IN SYSTEM LOW CONFIDENCE
ON DETAILS.

ANOMALOUS SYSTEM WILL STRENGTHEN OVER THE GREAT LAKES TUESDAY INTO
WEDNESDAY. A SECONDARY SHORTWAVE WILL ROUND THE DEEP TROUGH AND
DEVELOP A SECONDARY LOW PRESSURE ALONG THE COLD FRONT. THIS
SECONDARY LOW WILL STRENGTHEN AND PASS WEST OF SOUTHERN NEW ENGLAND.
THIS SYSTEM WILL CONTINUE TO DEEPEN AS IT MOVES TOWARDS EASTERN
CANADA SWINGING A COLD FRONT ACROSS THE NORTHEAST.

STRONG SOUTHERLY JET OUT AHEAD OF THE FRONT WITH A GULF MOISTURE
CONNECTION WILL IMPACT SOUTHERN NEW ENGLAND ON CHRISTMAS EVE. THIS
STRONG JET WILL YIELD FOR PCPN IN THE LIQUID VARIETY.  PW ANOMALIES
ARE BETWEEN +4 TO +5 STANDARD DEVIATIONS ABOVE NORMAL WHICH IS QUITE
ANOMALOUS FOR THIS TIME OF YEAR. IN FACT CURRENT PWATS ARE PROGGED
ABOVE 1.6 INCHES WITH MODEL QPF OVER 2 INCHES...AT THE VERY LEAST
COULD SEE URBAN AND POOR DRAINAGE FLOODING. LATEST EC EVEN SHOWS
OVER 2.5 INCHES OF QPF...AND WITH THE TROPICAL CONNECTION AND STRONG
SOUTHERLY FLOW COULD SEE HIGHER AMOUNTS DUE TO TOPOGRAPHY
ENHANCEMENTS. RAINFALL RECORDS MAY FALL IF EVERYTHING FALLS INTO
PLACE.

AHEAD OF THE FRONT...SOUTHERN NEW ENGLAND WILL WARM SECTOR WED INTO
THUR MORNING ALLOWING FOR TEMPERATURES TO BE WELL ABOVE AVERAGE. IN
FACT WE MAY BE CLOSE AT BREAKING RECORD HIGH TEMPS IF TEMPS WARM TO
60F OR ABOVE ON CHRISTMAS EVE. SINCE WE WILL BE IN THE WARM
SECTOR...AND SHOWALTERS CLOSE TO ZERO...ISOLATED THUNDER IS STILL
POSSIBLE.

STRONG LOW LEVEL WINDS WILL ALSO BE A CONCERN ESPECIALLY WEDNESDAY
NIGHT. THE ECMWF SHOWS EAST-SOUTHEAST WINDS 30-40 KNOTS ON WEDNESDAY
INCREASING TO 60-75 KNOTS BY WEDNESDAY NIGHT. STRONG DOWNPOURS MAY
OVERCOME THE LOW LEVEL INVERSION AND BRING STRONG GUSTS OF AT LEAST
30-40 KNOTS ESPECIALLY ALONG THE SOUTH COAST. A WIND ADVISORY MAY BE
NEEDED IN SOME AREAS.

CHRISTMAS DAY...MODERATE CONFIDENCE.

AS THE COLD FRONT PASSES THROUGH EARLY CHRISTMAS DAY...THE WEST
WINDS WILL HELP DRY THE AIRMASS ALLOWING FOR PARTLY SUNNY SKIES.
STRONG CAA ON THURSDAY WILL ALLOW DESCENT MIXING. WINDS IN THE SFC-
850 MB LAYER WILL BE 30-40 KNOTS AND POSSIBLY A LITTLE
HIGHER...WHICH WOULD REQUIRE A WIND ADVISORY FOR MUCH OF THE AREA.

FRIDAY-SUNDAY...LOWER CONFIDENCE

WEAK HIGH PRESSURE BUILDS OVER THE AREA FRIDAY INTO SATURDAY. THE
NEXT SHORTWAVE APPROACHES LATE SATURDAY INTO SUNDAY AND SHOULD BRING
INCREASING CLOUDS FROM WEST TO EAST ALONG WITH A CHANCE OF RAIN OR
SNOW SHOWERS MAINLY IN THE AFTERNOON AND AT NIGHT.

&&

.AVIATION /20Z SUNDAY THROUGH FRIDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH MONDAY NIGHT/...

THROUGH TONIGHT...MODERATE CONFIDENCE. MAINLY MVFR/IFR CONDITIONS
THROUGH TONIGHT. EXCEPTION RIGHT NOW IS THE CAPE AND ISLANDS WHERE
VFR CONDITIONS ARE IN PLACE. BELIEVE CONDITIONS WILL DETERIORATE
LATER TONIGHT THERE. WIDESPREAD LIGHT SNOW SHOWERS ARE AFFECTING
ALL OF SOUTHERN NEW ENGLAND THIS AFTERNOON. EXPECT THIS ACTIVITY
TO BECOME MORE SCATTERED IN NATURE. RAIN SHOWERS ACROSS MOST OF
PLYMOUTH COUNTY AND ONTO THE CAPE/ISLANDS WITH SNOW SHOWERS NORTH
AND WEST.

MONDAY AND MONDAY NIGHT...MODERATE CONFIDENCE. MAINLY MVFR
CONDITIONS CONTINUE IN SCATTERED LIGHT SNOW SHOWERS. LIGHT FZRA
POSSIBLE LATE MONDAY NIGHT ACROSS NW MASSACHUSETTS.

KBOS TERMINAL...MODERATE CONFIDENCE.

KBDL TERMINAL...MODERATE CONFIDENCE.

OUTLOOK...MONDAY THROUGH THURSDAY...MODERATE CONFIDENCE.

MONDAY...MVFR CIGS CONTINUE IN RI/EASTERN MASS IN MARINE EAST FLOW.
VFR IN THE WEST.

TUESDAY...VFR WITH SCATTERED MVFR IN ANY RAIN/SNOW SHOWERS.

WEDNESDAY...CONDITIONS LOWERING TO IFR IN RAIN/HEAVY RAIN. ISOLATED
THUNDERSTORMS POSSIBLE ESPECIALLY WEDNESDAY NIGHT. EAST-SOUTHEAST
SURFACE WINDS MAY GUST TO 35-45 KNOTS. WINDS AT 2000 FEET AGL WILL
REACH 50-60 KNOTS WEDNESDAY AFTERNOON AND EARLY NIGHT CREATING LOW
LEVEL WIND SHEAR CONCERNS.

CHRISTMAS DAY...WEST WIND GUSTING 30-40 KNOTS. CONDITIONS IMPROVING
TO VFR AS THE WIND BRINGS IN COOLER DRIER AIR.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

HIGH PRESSURE ACROSS QUEBEC AND THE MARITIMES WILL RESULT IN
PERSISTENT NORTHEASTERLY TO EASTERLY WINDS ACROSS THE WATERS THROUGH
MONDAY.  THIS WILL RESULT IN BUILDING SEAS ON THE EASTERN WATERS
DESPITE WIND GUSTS UP TO 20 KNOTS.  SEAS BUILD TO AT LEAST 5 FEET ON
THE EASTERN WATERS BY MIDDAY MONDAY.  HAVE ISSUED A SMALL CRAFT
ADVISORY FOR THE EASTERN WATERS BEGINNING MIDDAY MONDAY AND
CONTINUING THROUGH TUESDAY MORNING.  WINDS INCREASE TO NEAR 25 KTS
ON THE SOUTHERN WATERS BY 12Z TUESDAY.

OUTLOOK...TUESDAY THROUGH FRIDAY...MODERATE CONFIDENCE

MONDAY...EAST TO NORTHEAST WINDS GUSTING AROUND 15 KNOTS OR LESS.
SEAS WILL HOLD AROUND 3-4 FEET...MAY INCREASE TO 5FT IN NORTHEAST
FLOW AS GUIDANCE MAY BE UNDERDONE.

TUESDAY... INCREASING EAST WINDS WITH FREQUENT GUSTS 25 TO 30 KNOTS.
SEAS WILL BUILD TO 5-6 FEET ON THE EXPOSED WATERS.  A SMALL CRAFT
ADVISORY MAY BE NEEDED.

WEDNESDAY...RAIN WILL BE HEAVY AT TIMES PRODUCING POOR VISIBILITY.
INCREASING SOUTHEAST WINDS 20-25 SUSTAINED AND 40 KNOT GUSTS.  WINDS
SHOULD SHIFT TO SOUTH WEDNESDAY NIGHT AND SOUTHWEST TOWARD THURSDAY
MORNING. RAIN WILL TAPER OFF WITH THE WIND SHIFT TO SOUTHWEST. SEAS
WILL CONTINUE TO BUILD WITH 7-11 FEET HEIGHTS ON THE EXPOSED WATERS.
A GALE WARNING WILL BE NEEDED...WITH A LOW PROB OF A FEW STORM FORCE
GUSTS ACROSS THE EASTERN OUTER WATERS.

CHRISTMAS DAY... WEST SOUTHWEST WINDS WILL CONTINUE TO GUST 35-40
KNOTS...SO A CONTINUED GALE WARNING MAY BE NEEDED. SEAS OF 7-15 FEET
ARE POSSIBLE ON THE EXPOSED WATERS...AND 5 FEET IS POSSIBLE ON SOME
OF THE NEARSHORE WATERS.

&&

.TIDES/COASTAL FLOODING...
HIGH ASTRONOMICAL TIDES WILL OCCUR TUESDAY THROUGH THURSDAY.

TUESDAY...HIGH TIDE AT BOSTON WILL BE 11.6 FT. THERE WILL BE ONSHORE
FLOW DURING THIS HIGH TIDE ALLOWING FOR MINOR SPLASHOVER. IF WINDS
INCREASE THEN COULD SEE SOME POCKETS OF MINOR COASTAL FLOODING.

WEDNESDAY...WINDS SHIFT TO A MORE SOUTHEASTERLY FLOW DURING THE DAY
AND INCREASE QUICKLY AS AN APPROACHING SYSTEM BRINGS DECENT PRESSURE
FALLS. THE WEDNESDAY AFTERNOON HIGH TIDE IN BOSTON IS 11.7 FT AND
STRONG SOUTHEASTERLY WINDS WILL BE JUST OFFSHORE. RIGHT NOW BELIEVE
MINOR COASTAL FLOODING IS POSSIBLE ALONG THE EAST COAST.

WEDNESDAY EVENING...SOUTHERLY WINDS ARE EXPECTED AND ASTRONOMICAL
TIDES INCREASE ALONG THE SOUTH COAST. HIGH TIDE IN PROVIDENCE WILL
BE 5.2 FT. 925 MB LLJ STRENGTHENS TO 50-60 KTS WHICH COULD PUSH A
DECENT SURGE UP ALONG THE SOUTH COAST DURING THE TIME OF HIGH TIDE.
THINKING THAT MINOR COASTAL FLOODING COULD OCCUR BUT CANNOT RULE OUT
MODERATE ALONG THE SOUTH COAST...ESPECIALLY IF LLJ CONTINUES TO
STRENGTHEN.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...DUNTEN/RLG
NEAR TERM...RLG
SHORT TERM...RLG
LONG TERM...DUNTEN
AVIATION...DUNTEN/RLG
MARINE...DUNTEN/RLG
TIDES/COASTAL FLOODING...




000
FXUS61 KGYX 212012
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
312 PM EST SUN DEC 21 2014

.SYNOPSIS...
AN ONSHORE FLOW MAY TRIGGER SOME FLURRIES OR LIGHT SNOW MAINLY OVER
SOUTHERN REGIONS RIGHT THROUGH TUESDAY. A SIGNIFICANT LOW
PRESSURE SYSTEM SYSTEM WILL GRADUALLY ORGANIZE WEDNESDAY...BEFORE
MOVING OVER THE GREAT LAKES. THIS COULD BRING WINDY CONDITIONS AND
THE POTENTIAL FOR HEAVY RAIN AROUND CHRISTMAS EVE INTO EARLY
CHRISTMAS MORNING. ANOTHER LOW PRESSURE SYSTEM WILL PASS BY TO OUR
NORTHWEST LATE IN THE WEEK AND EARLY NEXT WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
AREAS OF LIGHT SNOW WILL CONTINUE INTO THIS EVENING HOURS
ASSOCIATED WITH "OCEAN EFFECT" ONSHORE FLOW...AND ALSO DUE TO THE
PROXIMITY OF A WEAK MID LEVEL LOW. IN GENERAL...WILL BE LOWERING
POPS AS WE HEAD INTO THE LATE EVENING HOURS...WITH THE GREATEST
CHANCE OF A SNOW SHOWERS ALONG AND NEAR THE COASTLINE. THE BEACH
AREAS WILL NEED TO BE MONITORED HOWEVER...AS THERE IS SOME
INDICATION OF A WEAK NORLUN TROUGH OVER THE REGION.

&&

.SHORT TERM /MONDAY AND MONDAY NIGHT/...
SCATTERED SNOW SHOWERS AND FLURRIES WILL CONTINUE RIGHT THROUGH
MONDAY NIGHT OVER SOUTHERN AREAS DUE TO A PERSISTENT NORTHEAST
FLOW OVER THE MOIST GULF OF MAINE. MESO MODELS WITHIN THE 12Z
MODEL SUITE CONTINUE TO HAVE A DIFFICULT TIME PICKING UP ON THIS
LOW LEVEL MOISTURE AND PRECIP. HAVE THEREFORE RAISED POPS ABOVE
ALL AVAILABLE GUIDANCE.

A COLD AIR DAMMING SIGNATURE WILL BE FORMING BY MONDAY NIGHT.
THEREFORE...THE PTYPE SHOULD BE ALL SNOW THROUGH THE SHORT TERM
PORTION OF THE FORECAST...BEFORE THE WARM AIR POURS INTO THE
REGION.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
THE WEAK ONSHORE FLOW CONTINUES INTO TUESDAY WITH LOW LEVEL
MOISTURE DEEPEST ALONG THE COAST. ON TUESDAY THE WARMER ONSHORE
FLOW DEEPENS AS THE HIGH MOVES FURTHER OFFSHORE ALLOWING A
SOUTHEAST FLOW TO INCREASE...SO SCATTERED LIGHT INTERMITTENT
PRECIPITATION EXPECTED...MOSTLY IN THE FORM OF RAIN EXCEPT SOME
IN THE FORM OF LIGHT SNOW IN THE MOUNTAINS BEFORE CHANGING OVER TO
RAIN EVEN IN THOSE AREAS. THE MAIN EVENT WILL BE THE ONSET OF THE
HEAVIER PRECIPITATION LATE CHRISTMAS EVE AND ESPECIALLY CHRISTMAS
DAY AND NIGHT WHERE THE RAIN WILL BECOME HEAVY AT TIMES AS A
STRONG WARM ADVECTION PATTERN DEVELOPS BEING ACCOMPANIED BY A
STRONG LOW/MID LEVEL JET. THE MAIN UPPER LOW PASSES WELL TO OUR
WEST AS IT MOVES THROUGH THE GREAT LAKES. QPF TOTALS FOR LATE
TUESDAY INTO THURSDAY COULD BE IN THE 2-4 INCH RANGE. DUE TO VERY
WARM AIR THIS WILL BE IN THE FORM OF RAIN EVEN IN THE MOUNTAINS.
SOME FLOODING PROBLEMS MAY ARISE IN THE HEADWATERS BY WEDNESDAY
NIGHT OR THURSDAY DUE TO THE COMBINATION OF SOME SNOWMELT AND THE
HEAVY RAINS. ALL MODELS AGREE ON MILD TEMPERATURES...USED A BLEND
OF THE MODELS.

SYSTEM FINALLY EXITS TO THE NORTHEAST BY THURSDAY AFTERNOON AS A
DRY SLOT MOVES ACROSS THE AREA FOLLOWED BY A COLD FRONT WITH A
RETURN TO SEASONAL TEMPS FOR FRI.

ANOTHER SYSTEM WHICH WILL BE WEAKER WILL APPROACH FOR THE WEEKEND.
MODELS DIFFER IN RUN TO RUN CONTINUITY AND ALSO VARIANCES IN
TIMING, STRENGTH, AND POSITION OF THIS SYSTEM. FOR NOW WILL BROAD
BRUSH DUE TO ALL THE UNCERTAINTY AS WELL AS PTYPE.

&&

.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
SHORT TERM...MAINLY VFR THROUGH MONDAY NIGHT...HOWEVER THERE MAY
BE BRIEFLY MVFR CONDITIONS IN SCATTERED SNOW SHOWERS SOUTHERN
LOCATIONS.

LONG TERM...MVFR CONDS EXPECTED TUE AND THEN LOWERING TO IFR TUE
NIGHT AND LIFR CONDITIONS WED INTO THU. CONDITIONS IMPROVE BY LATE
THU TO VFR.

&&

.MARINE...
SHORT TERM...WINDS AND SEAS WILL REMAIN MOSTLY OUT OF THE
NORTHEAST THROUGH MONDAY NIGHT. WINDS AND SEAS WILL REMAIN BELOW
SCA CONDITIONS.

LONG TERM...STRONG LOW PRESSURE WILL MOVE WELL TO THE WEST AND
WILL CAUSE WINDS TO INCREASE TO GALES TUESDAY NIGHT THROUGH
WEDNESDAY WITH BORDERLINE STORM FORCE WIND GUSTS POSSIBLE
WEDNESDAY NIGHT. SEAS COULD BUILD IN EXCESS OF 15 FT OVER THE
OUTER WATERS BY WEDNESDAY NIGHT OR EARLY THURSDAY. GUIDANCE LOOKS
LOW ON BOTH WINDS AND SEAS WHICH IS TYPICAL FOR THESE TYPE OF
EVENTS.

&&

.HYDROLOGY...MODELS CONTINUE TO BACK OFF ON RAINFALL TOTALS FOR
THE CHRISTMAS EVE/EARLY CHRISTMAS MORNING EVENT...BUT AREA STILL
IN THE 1 TO 3 INCH RANGE. HOPING THE SNOWPACK IN THE MOUNTAINS AND
FOOTHILLS WILL TAKE IN SOME OF THE 1 TO 2 INCH RAINFALL AMOUNTS IN
THAT AREA...BUT STILL EXPECTED RAPID RISES IN THE HEADWATERS. OVER
SOUTHERN LOCATIONS...2 TO 3 INCHES OF RAIN EXPECTED. IN ANY
CASE...FLOODING IS A DISTINCT POSSIBLY CHRISTMAS EVE AND CHRISTMAS
MORNING ASSOCIATED WITH THE HEAVY RAIN AND SNOWMELT.

&&

.TIDES/COASTAL FLOODING...
ASTRONOMICAL TIDES ARE AT THEIR PEAK FOR THE MONTH. THIS...IN
COMBINATION WITH STRONG SOUTHERLY DEVELOPING GALES (WITH POSSIBLE
STORM FORCE GUSTS) WILL LIKELY ALLOW FOR ABOUT A 1 FOOT STORM
SURGE. WITH BUILDING WAVES IN THE 15 FOOT RANGE...EXPECT A FEW
AREAS TO HAVE COASTAL FLOODING...SPLASH-OVER AND BEACH EROSION.

NART WAVE RUN-UP MATRICES ARE ALREADY PREDICTING THE POTENTIAL FOR
COASTAL FLOODING...OVERWASH AND EROSION ACROSS MOST LOCATIONS IN
MAINE AND NEW HAMPSHIRE BASED ON OUR CURRENT STORM SURGE AND WAVE
PREDICTIONS.

THE QUESTION IS HOWEVER...WHEN WILL THE PEAK WINDS AND SEAS
ARRIVE? RIGHT NOW IT IS TOO EARLY TO TELL IF THIS PERIOD OF
INCLEMENT WEATHER/OCEAN CONDITIONS WILL ARRIVE NEAR THE TIME OF
HIGH TIDE. THE MIDDAY TIDES ON CHRISTMAS EVE AND CHRISTMAS DAY ARE
THE HIGHEST AT 11 FEET...WHILE THE 1 AM CHRISTMAS MORNING HIGH
TIDE IS LOWER AT 10 FEET.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.

&&

$$
JC/RAM




000
FXUS61 KGYX 212012
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
312 PM EST SUN DEC 21 2014

.SYNOPSIS...
AN ONSHORE FLOW MAY TRIGGER SOME FLURRIES OR LIGHT SNOW MAINLY OVER
SOUTHERN REGIONS RIGHT THROUGH TUESDAY. A SIGNIFICANT LOW
PRESSURE SYSTEM SYSTEM WILL GRADUALLY ORGANIZE WEDNESDAY...BEFORE
MOVING OVER THE GREAT LAKES. THIS COULD BRING WINDY CONDITIONS AND
THE POTENTIAL FOR HEAVY RAIN AROUND CHRISTMAS EVE INTO EARLY
CHRISTMAS MORNING. ANOTHER LOW PRESSURE SYSTEM WILL PASS BY TO OUR
NORTHWEST LATE IN THE WEEK AND EARLY NEXT WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
AREAS OF LIGHT SNOW WILL CONTINUE INTO THIS EVENING HOURS
ASSOCIATED WITH "OCEAN EFFECT" ONSHORE FLOW...AND ALSO DUE TO THE
PROXIMITY OF A WEAK MID LEVEL LOW. IN GENERAL...WILL BE LOWERING
POPS AS WE HEAD INTO THE LATE EVENING HOURS...WITH THE GREATEST
CHANCE OF A SNOW SHOWERS ALONG AND NEAR THE COASTLINE. THE BEACH
AREAS WILL NEED TO BE MONITORED HOWEVER...AS THERE IS SOME
INDICATION OF A WEAK NORLUN TROUGH OVER THE REGION.

&&

.SHORT TERM /MONDAY AND MONDAY NIGHT/...
SCATTERED SNOW SHOWERS AND FLURRIES WILL CONTINUE RIGHT THROUGH
MONDAY NIGHT OVER SOUTHERN AREAS DUE TO A PERSISTENT NORTHEAST
FLOW OVER THE MOIST GULF OF MAINE. MESO MODELS WITHIN THE 12Z
MODEL SUITE CONTINUE TO HAVE A DIFFICULT TIME PICKING UP ON THIS
LOW LEVEL MOISTURE AND PRECIP. HAVE THEREFORE RAISED POPS ABOVE
ALL AVAILABLE GUIDANCE.

A COLD AIR DAMMING SIGNATURE WILL BE FORMING BY MONDAY NIGHT.
THEREFORE...THE PTYPE SHOULD BE ALL SNOW THROUGH THE SHORT TERM
PORTION OF THE FORECAST...BEFORE THE WARM AIR POURS INTO THE
REGION.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
THE WEAK ONSHORE FLOW CONTINUES INTO TUESDAY WITH LOW LEVEL
MOISTURE DEEPEST ALONG THE COAST. ON TUESDAY THE WARMER ONSHORE
FLOW DEEPENS AS THE HIGH MOVES FURTHER OFFSHORE ALLOWING A
SOUTHEAST FLOW TO INCREASE...SO SCATTERED LIGHT INTERMITTENT
PRECIPITATION EXPECTED...MOSTLY IN THE FORM OF RAIN EXCEPT SOME
IN THE FORM OF LIGHT SNOW IN THE MOUNTAINS BEFORE CHANGING OVER TO
RAIN EVEN IN THOSE AREAS. THE MAIN EVENT WILL BE THE ONSET OF THE
HEAVIER PRECIPITATION LATE CHRISTMAS EVE AND ESPECIALLY CHRISTMAS
DAY AND NIGHT WHERE THE RAIN WILL BECOME HEAVY AT TIMES AS A
STRONG WARM ADVECTION PATTERN DEVELOPS BEING ACCOMPANIED BY A
STRONG LOW/MID LEVEL JET. THE MAIN UPPER LOW PASSES WELL TO OUR
WEST AS IT MOVES THROUGH THE GREAT LAKES. QPF TOTALS FOR LATE
TUESDAY INTO THURSDAY COULD BE IN THE 2-4 INCH RANGE. DUE TO VERY
WARM AIR THIS WILL BE IN THE FORM OF RAIN EVEN IN THE MOUNTAINS.
SOME FLOODING PROBLEMS MAY ARISE IN THE HEADWATERS BY WEDNESDAY
NIGHT OR THURSDAY DUE TO THE COMBINATION OF SOME SNOWMELT AND THE
HEAVY RAINS. ALL MODELS AGREE ON MILD TEMPERATURES...USED A BLEND
OF THE MODELS.

SYSTEM FINALLY EXITS TO THE NORTHEAST BY THURSDAY AFTERNOON AS A
DRY SLOT MOVES ACROSS THE AREA FOLLOWED BY A COLD FRONT WITH A
RETURN TO SEASONAL TEMPS FOR FRI.

ANOTHER SYSTEM WHICH WILL BE WEAKER WILL APPROACH FOR THE WEEKEND.
MODELS DIFFER IN RUN TO RUN CONTINUITY AND ALSO VARIANCES IN
TIMING, STRENGTH, AND POSITION OF THIS SYSTEM. FOR NOW WILL BROAD
BRUSH DUE TO ALL THE UNCERTAINTY AS WELL AS PTYPE.

&&

.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
SHORT TERM...MAINLY VFR THROUGH MONDAY NIGHT...HOWEVER THERE MAY
BE BRIEFLY MVFR CONDITIONS IN SCATTERED SNOW SHOWERS SOUTHERN
LOCATIONS.

LONG TERM...MVFR CONDS EXPECTED TUE AND THEN LOWERING TO IFR TUE
NIGHT AND LIFR CONDITIONS WED INTO THU. CONDITIONS IMPROVE BY LATE
THU TO VFR.

&&

.MARINE...
SHORT TERM...WINDS AND SEAS WILL REMAIN MOSTLY OUT OF THE
NORTHEAST THROUGH MONDAY NIGHT. WINDS AND SEAS WILL REMAIN BELOW
SCA CONDITIONS.

LONG TERM...STRONG LOW PRESSURE WILL MOVE WELL TO THE WEST AND
WILL CAUSE WINDS TO INCREASE TO GALES TUESDAY NIGHT THROUGH
WEDNESDAY WITH BORDERLINE STORM FORCE WIND GUSTS POSSIBLE
WEDNESDAY NIGHT. SEAS COULD BUILD IN EXCESS OF 15 FT OVER THE
OUTER WATERS BY WEDNESDAY NIGHT OR EARLY THURSDAY. GUIDANCE LOOKS
LOW ON BOTH WINDS AND SEAS WHICH IS TYPICAL FOR THESE TYPE OF
EVENTS.

&&

.HYDROLOGY...MODELS CONTINUE TO BACK OFF ON RAINFALL TOTALS FOR
THE CHRISTMAS EVE/EARLY CHRISTMAS MORNING EVENT...BUT AREA STILL
IN THE 1 TO 3 INCH RANGE. HOPING THE SNOWPACK IN THE MOUNTAINS AND
FOOTHILLS WILL TAKE IN SOME OF THE 1 TO 2 INCH RAINFALL AMOUNTS IN
THAT AREA...BUT STILL EXPECTED RAPID RISES IN THE HEADWATERS. OVER
SOUTHERN LOCATIONS...2 TO 3 INCHES OF RAIN EXPECTED. IN ANY
CASE...FLOODING IS A DISTINCT POSSIBLY CHRISTMAS EVE AND CHRISTMAS
MORNING ASSOCIATED WITH THE HEAVY RAIN AND SNOWMELT.

&&

.TIDES/COASTAL FLOODING...
ASTRONOMICAL TIDES ARE AT THEIR PEAK FOR THE MONTH. THIS...IN
COMBINATION WITH STRONG SOUTHERLY DEVELOPING GALES (WITH POSSIBLE
STORM FORCE GUSTS) WILL LIKELY ALLOW FOR ABOUT A 1 FOOT STORM
SURGE. WITH BUILDING WAVES IN THE 15 FOOT RANGE...EXPECT A FEW
AREAS TO HAVE COASTAL FLOODING...SPLASH-OVER AND BEACH EROSION.

NART WAVE RUN-UP MATRICES ARE ALREADY PREDICTING THE POTENTIAL FOR
COASTAL FLOODING...OVERWASH AND EROSION ACROSS MOST LOCATIONS IN
MAINE AND NEW HAMPSHIRE BASED ON OUR CURRENT STORM SURGE AND WAVE
PREDICTIONS.

THE QUESTION IS HOWEVER...WHEN WILL THE PEAK WINDS AND SEAS
ARRIVE? RIGHT NOW IT IS TOO EARLY TO TELL IF THIS PERIOD OF
INCLEMENT WEATHER/OCEAN CONDITIONS WILL ARRIVE NEAR THE TIME OF
HIGH TIDE. THE MIDDAY TIDES ON CHRISTMAS EVE AND CHRISTMAS DAY ARE
THE HIGHEST AT 11 FEET...WHILE THE 1 AM CHRISTMAS MORNING HIGH
TIDE IS LOWER AT 10 FEET.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.

&&

$$
JC/RAM




000
FXUS61 KGYX 212012
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
312 PM EST SUN DEC 21 2014

.SYNOPSIS...
AN ONSHORE FLOW MAY TRIGGER SOME FLURRIES OR LIGHT SNOW MAINLY OVER
SOUTHERN REGIONS RIGHT THROUGH TUESDAY. A SIGNIFICANT LOW
PRESSURE SYSTEM SYSTEM WILL GRADUALLY ORGANIZE WEDNESDAY...BEFORE
MOVING OVER THE GREAT LAKES. THIS COULD BRING WINDY CONDITIONS AND
THE POTENTIAL FOR HEAVY RAIN AROUND CHRISTMAS EVE INTO EARLY
CHRISTMAS MORNING. ANOTHER LOW PRESSURE SYSTEM WILL PASS BY TO OUR
NORTHWEST LATE IN THE WEEK AND EARLY NEXT WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
AREAS OF LIGHT SNOW WILL CONTINUE INTO THIS EVENING HOURS
ASSOCIATED WITH "OCEAN EFFECT" ONSHORE FLOW...AND ALSO DUE TO THE
PROXIMITY OF A WEAK MID LEVEL LOW. IN GENERAL...WILL BE LOWERING
POPS AS WE HEAD INTO THE LATE EVENING HOURS...WITH THE GREATEST
CHANCE OF A SNOW SHOWERS ALONG AND NEAR THE COASTLINE. THE BEACH
AREAS WILL NEED TO BE MONITORED HOWEVER...AS THERE IS SOME
INDICATION OF A WEAK NORLUN TROUGH OVER THE REGION.

&&

.SHORT TERM /MONDAY AND MONDAY NIGHT/...
SCATTERED SNOW SHOWERS AND FLURRIES WILL CONTINUE RIGHT THROUGH
MONDAY NIGHT OVER SOUTHERN AREAS DUE TO A PERSISTENT NORTHEAST
FLOW OVER THE MOIST GULF OF MAINE. MESO MODELS WITHIN THE 12Z
MODEL SUITE CONTINUE TO HAVE A DIFFICULT TIME PICKING UP ON THIS
LOW LEVEL MOISTURE AND PRECIP. HAVE THEREFORE RAISED POPS ABOVE
ALL AVAILABLE GUIDANCE.

A COLD AIR DAMMING SIGNATURE WILL BE FORMING BY MONDAY NIGHT.
THEREFORE...THE PTYPE SHOULD BE ALL SNOW THROUGH THE SHORT TERM
PORTION OF THE FORECAST...BEFORE THE WARM AIR POURS INTO THE
REGION.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
THE WEAK ONSHORE FLOW CONTINUES INTO TUESDAY WITH LOW LEVEL
MOISTURE DEEPEST ALONG THE COAST. ON TUESDAY THE WARMER ONSHORE
FLOW DEEPENS AS THE HIGH MOVES FURTHER OFFSHORE ALLOWING A
SOUTHEAST FLOW TO INCREASE...SO SCATTERED LIGHT INTERMITTENT
PRECIPITATION EXPECTED...MOSTLY IN THE FORM OF RAIN EXCEPT SOME
IN THE FORM OF LIGHT SNOW IN THE MOUNTAINS BEFORE CHANGING OVER TO
RAIN EVEN IN THOSE AREAS. THE MAIN EVENT WILL BE THE ONSET OF THE
HEAVIER PRECIPITATION LATE CHRISTMAS EVE AND ESPECIALLY CHRISTMAS
DAY AND NIGHT WHERE THE RAIN WILL BECOME HEAVY AT TIMES AS A
STRONG WARM ADVECTION PATTERN DEVELOPS BEING ACCOMPANIED BY A
STRONG LOW/MID LEVEL JET. THE MAIN UPPER LOW PASSES WELL TO OUR
WEST AS IT MOVES THROUGH THE GREAT LAKES. QPF TOTALS FOR LATE
TUESDAY INTO THURSDAY COULD BE IN THE 2-4 INCH RANGE. DUE TO VERY
WARM AIR THIS WILL BE IN THE FORM OF RAIN EVEN IN THE MOUNTAINS.
SOME FLOODING PROBLEMS MAY ARISE IN THE HEADWATERS BY WEDNESDAY
NIGHT OR THURSDAY DUE TO THE COMBINATION OF SOME SNOWMELT AND THE
HEAVY RAINS. ALL MODELS AGREE ON MILD TEMPERATURES...USED A BLEND
OF THE MODELS.

SYSTEM FINALLY EXITS TO THE NORTHEAST BY THURSDAY AFTERNOON AS A
DRY SLOT MOVES ACROSS THE AREA FOLLOWED BY A COLD FRONT WITH A
RETURN TO SEASONAL TEMPS FOR FRI.

ANOTHER SYSTEM WHICH WILL BE WEAKER WILL APPROACH FOR THE WEEKEND.
MODELS DIFFER IN RUN TO RUN CONTINUITY AND ALSO VARIANCES IN
TIMING, STRENGTH, AND POSITION OF THIS SYSTEM. FOR NOW WILL BROAD
BRUSH DUE TO ALL THE UNCERTAINTY AS WELL AS PTYPE.

&&

.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
SHORT TERM...MAINLY VFR THROUGH MONDAY NIGHT...HOWEVER THERE MAY
BE BRIEFLY MVFR CONDITIONS IN SCATTERED SNOW SHOWERS SOUTHERN
LOCATIONS.

LONG TERM...MVFR CONDS EXPECTED TUE AND THEN LOWERING TO IFR TUE
NIGHT AND LIFR CONDITIONS WED INTO THU. CONDITIONS IMPROVE BY LATE
THU TO VFR.

&&

.MARINE...
SHORT TERM...WINDS AND SEAS WILL REMAIN MOSTLY OUT OF THE
NORTHEAST THROUGH MONDAY NIGHT. WINDS AND SEAS WILL REMAIN BELOW
SCA CONDITIONS.

LONG TERM...STRONG LOW PRESSURE WILL MOVE WELL TO THE WEST AND
WILL CAUSE WINDS TO INCREASE TO GALES TUESDAY NIGHT THROUGH
WEDNESDAY WITH BORDERLINE STORM FORCE WIND GUSTS POSSIBLE
WEDNESDAY NIGHT. SEAS COULD BUILD IN EXCESS OF 15 FT OVER THE
OUTER WATERS BY WEDNESDAY NIGHT OR EARLY THURSDAY. GUIDANCE LOOKS
LOW ON BOTH WINDS AND SEAS WHICH IS TYPICAL FOR THESE TYPE OF
EVENTS.

&&

.HYDROLOGY...MODELS CONTINUE TO BACK OFF ON RAINFALL TOTALS FOR
THE CHRISTMAS EVE/EARLY CHRISTMAS MORNING EVENT...BUT AREA STILL
IN THE 1 TO 3 INCH RANGE. HOPING THE SNOWPACK IN THE MOUNTAINS AND
FOOTHILLS WILL TAKE IN SOME OF THE 1 TO 2 INCH RAINFALL AMOUNTS IN
THAT AREA...BUT STILL EXPECTED RAPID RISES IN THE HEADWATERS. OVER
SOUTHERN LOCATIONS...2 TO 3 INCHES OF RAIN EXPECTED. IN ANY
CASE...FLOODING IS A DISTINCT POSSIBLY CHRISTMAS EVE AND CHRISTMAS
MORNING ASSOCIATED WITH THE HEAVY RAIN AND SNOWMELT.

&&

.TIDES/COASTAL FLOODING...
ASTRONOMICAL TIDES ARE AT THEIR PEAK FOR THE MONTH. THIS...IN
COMBINATION WITH STRONG SOUTHERLY DEVELOPING GALES (WITH POSSIBLE
STORM FORCE GUSTS) WILL LIKELY ALLOW FOR ABOUT A 1 FOOT STORM
SURGE. WITH BUILDING WAVES IN THE 15 FOOT RANGE...EXPECT A FEW
AREAS TO HAVE COASTAL FLOODING...SPLASH-OVER AND BEACH EROSION.

NART WAVE RUN-UP MATRICES ARE ALREADY PREDICTING THE POTENTIAL FOR
COASTAL FLOODING...OVERWASH AND EROSION ACROSS MOST LOCATIONS IN
MAINE AND NEW HAMPSHIRE BASED ON OUR CURRENT STORM SURGE AND WAVE
PREDICTIONS.

THE QUESTION IS HOWEVER...WHEN WILL THE PEAK WINDS AND SEAS
ARRIVE? RIGHT NOW IT IS TOO EARLY TO TELL IF THIS PERIOD OF
INCLEMENT WEATHER/OCEAN CONDITIONS WILL ARRIVE NEAR THE TIME OF
HIGH TIDE. THE MIDDAY TIDES ON CHRISTMAS EVE AND CHRISTMAS DAY ARE
THE HIGHEST AT 11 FEET...WHILE THE 1 AM CHRISTMAS MORNING HIGH
TIDE IS LOWER AT 10 FEET.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.

&&

$$
JC/RAM




000
FXUS61 KGYX 212012
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
312 PM EST SUN DEC 21 2014

.SYNOPSIS...
AN ONSHORE FLOW MAY TRIGGER SOME FLURRIES OR LIGHT SNOW MAINLY OVER
SOUTHERN REGIONS RIGHT THROUGH TUESDAY. A SIGNIFICANT LOW
PRESSURE SYSTEM SYSTEM WILL GRADUALLY ORGANIZE WEDNESDAY...BEFORE
MOVING OVER THE GREAT LAKES. THIS COULD BRING WINDY CONDITIONS AND
THE POTENTIAL FOR HEAVY RAIN AROUND CHRISTMAS EVE INTO EARLY
CHRISTMAS MORNING. ANOTHER LOW PRESSURE SYSTEM WILL PASS BY TO OUR
NORTHWEST LATE IN THE WEEK AND EARLY NEXT WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
AREAS OF LIGHT SNOW WILL CONTINUE INTO THIS EVENING HOURS
ASSOCIATED WITH "OCEAN EFFECT" ONSHORE FLOW...AND ALSO DUE TO THE
PROXIMITY OF A WEAK MID LEVEL LOW. IN GENERAL...WILL BE LOWERING
POPS AS WE HEAD INTO THE LATE EVENING HOURS...WITH THE GREATEST
CHANCE OF A SNOW SHOWERS ALONG AND NEAR THE COASTLINE. THE BEACH
AREAS WILL NEED TO BE MONITORED HOWEVER...AS THERE IS SOME
INDICATION OF A WEAK NORLUN TROUGH OVER THE REGION.

&&

.SHORT TERM /MONDAY AND MONDAY NIGHT/...
SCATTERED SNOW SHOWERS AND FLURRIES WILL CONTINUE RIGHT THROUGH
MONDAY NIGHT OVER SOUTHERN AREAS DUE TO A PERSISTENT NORTHEAST
FLOW OVER THE MOIST GULF OF MAINE. MESO MODELS WITHIN THE 12Z
MODEL SUITE CONTINUE TO HAVE A DIFFICULT TIME PICKING UP ON THIS
LOW LEVEL MOISTURE AND PRECIP. HAVE THEREFORE RAISED POPS ABOVE
ALL AVAILABLE GUIDANCE.

A COLD AIR DAMMING SIGNATURE WILL BE FORMING BY MONDAY NIGHT.
THEREFORE...THE PTYPE SHOULD BE ALL SNOW THROUGH THE SHORT TERM
PORTION OF THE FORECAST...BEFORE THE WARM AIR POURS INTO THE
REGION.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
THE WEAK ONSHORE FLOW CONTINUES INTO TUESDAY WITH LOW LEVEL
MOISTURE DEEPEST ALONG THE COAST. ON TUESDAY THE WARMER ONSHORE
FLOW DEEPENS AS THE HIGH MOVES FURTHER OFFSHORE ALLOWING A
SOUTHEAST FLOW TO INCREASE...SO SCATTERED LIGHT INTERMITTENT
PRECIPITATION EXPECTED...MOSTLY IN THE FORM OF RAIN EXCEPT SOME
IN THE FORM OF LIGHT SNOW IN THE MOUNTAINS BEFORE CHANGING OVER TO
RAIN EVEN IN THOSE AREAS. THE MAIN EVENT WILL BE THE ONSET OF THE
HEAVIER PRECIPITATION LATE CHRISTMAS EVE AND ESPECIALLY CHRISTMAS
DAY AND NIGHT WHERE THE RAIN WILL BECOME HEAVY AT TIMES AS A
STRONG WARM ADVECTION PATTERN DEVELOPS BEING ACCOMPANIED BY A
STRONG LOW/MID LEVEL JET. THE MAIN UPPER LOW PASSES WELL TO OUR
WEST AS IT MOVES THROUGH THE GREAT LAKES. QPF TOTALS FOR LATE
TUESDAY INTO THURSDAY COULD BE IN THE 2-4 INCH RANGE. DUE TO VERY
WARM AIR THIS WILL BE IN THE FORM OF RAIN EVEN IN THE MOUNTAINS.
SOME FLOODING PROBLEMS MAY ARISE IN THE HEADWATERS BY WEDNESDAY
NIGHT OR THURSDAY DUE TO THE COMBINATION OF SOME SNOWMELT AND THE
HEAVY RAINS. ALL MODELS AGREE ON MILD TEMPERATURES...USED A BLEND
OF THE MODELS.

SYSTEM FINALLY EXITS TO THE NORTHEAST BY THURSDAY AFTERNOON AS A
DRY SLOT MOVES ACROSS THE AREA FOLLOWED BY A COLD FRONT WITH A
RETURN TO SEASONAL TEMPS FOR FRI.

ANOTHER SYSTEM WHICH WILL BE WEAKER WILL APPROACH FOR THE WEEKEND.
MODELS DIFFER IN RUN TO RUN CONTINUITY AND ALSO VARIANCES IN
TIMING, STRENGTH, AND POSITION OF THIS SYSTEM. FOR NOW WILL BROAD
BRUSH DUE TO ALL THE UNCERTAINTY AS WELL AS PTYPE.

&&

.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
SHORT TERM...MAINLY VFR THROUGH MONDAY NIGHT...HOWEVER THERE MAY
BE BRIEFLY MVFR CONDITIONS IN SCATTERED SNOW SHOWERS SOUTHERN
LOCATIONS.

LONG TERM...MVFR CONDS EXPECTED TUE AND THEN LOWERING TO IFR TUE
NIGHT AND LIFR CONDITIONS WED INTO THU. CONDITIONS IMPROVE BY LATE
THU TO VFR.

&&

.MARINE...
SHORT TERM...WINDS AND SEAS WILL REMAIN MOSTLY OUT OF THE
NORTHEAST THROUGH MONDAY NIGHT. WINDS AND SEAS WILL REMAIN BELOW
SCA CONDITIONS.

LONG TERM...STRONG LOW PRESSURE WILL MOVE WELL TO THE WEST AND
WILL CAUSE WINDS TO INCREASE TO GALES TUESDAY NIGHT THROUGH
WEDNESDAY WITH BORDERLINE STORM FORCE WIND GUSTS POSSIBLE
WEDNESDAY NIGHT. SEAS COULD BUILD IN EXCESS OF 15 FT OVER THE
OUTER WATERS BY WEDNESDAY NIGHT OR EARLY THURSDAY. GUIDANCE LOOKS
LOW ON BOTH WINDS AND SEAS WHICH IS TYPICAL FOR THESE TYPE OF
EVENTS.

&&

.HYDROLOGY...MODELS CONTINUE TO BACK OFF ON RAINFALL TOTALS FOR
THE CHRISTMAS EVE/EARLY CHRISTMAS MORNING EVENT...BUT AREA STILL
IN THE 1 TO 3 INCH RANGE. HOPING THE SNOWPACK IN THE MOUNTAINS AND
FOOTHILLS WILL TAKE IN SOME OF THE 1 TO 2 INCH RAINFALL AMOUNTS IN
THAT AREA...BUT STILL EXPECTED RAPID RISES IN THE HEADWATERS. OVER
SOUTHERN LOCATIONS...2 TO 3 INCHES OF RAIN EXPECTED. IN ANY
CASE...FLOODING IS A DISTINCT POSSIBLY CHRISTMAS EVE AND CHRISTMAS
MORNING ASSOCIATED WITH THE HEAVY RAIN AND SNOWMELT.

&&

.TIDES/COASTAL FLOODING...
ASTRONOMICAL TIDES ARE AT THEIR PEAK FOR THE MONTH. THIS...IN
COMBINATION WITH STRONG SOUTHERLY DEVELOPING GALES (WITH POSSIBLE
STORM FORCE GUSTS) WILL LIKELY ALLOW FOR ABOUT A 1 FOOT STORM
SURGE. WITH BUILDING WAVES IN THE 15 FOOT RANGE...EXPECT A FEW
AREAS TO HAVE COASTAL FLOODING...SPLASH-OVER AND BEACH EROSION.

NART WAVE RUN-UP MATRICES ARE ALREADY PREDICTING THE POTENTIAL FOR
COASTAL FLOODING...OVERWASH AND EROSION ACROSS MOST LOCATIONS IN
MAINE AND NEW HAMPSHIRE BASED ON OUR CURRENT STORM SURGE AND WAVE
PREDICTIONS.

THE QUESTION IS HOWEVER...WHEN WILL THE PEAK WINDS AND SEAS
ARRIVE? RIGHT NOW IT IS TOO EARLY TO TELL IF THIS PERIOD OF
INCLEMENT WEATHER/OCEAN CONDITIONS WILL ARRIVE NEAR THE TIME OF
HIGH TIDE. THE MIDDAY TIDES ON CHRISTMAS EVE AND CHRISTMAS DAY ARE
THE HIGHEST AT 11 FEET...WHILE THE 1 AM CHRISTMAS MORNING HIGH
TIDE IS LOWER AT 10 FEET.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.

&&

$$
JC/RAM




000
FXUS61 KBOX 211801
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
101 PM EST SUN DEC 21 2014

.SYNOPSIS...
SCATTERED SNOW/RAIN SHOWERS CONTINUE THROUGH THIS AFTERNOON. WEAK
LOW PRESSURE WILL PASS SOUTH OF NEW ENGLAND BRINGING ANOTHER
PERIOD OF PRECIPITATION MONDAY NIGHT AND TUESDAY. A MUCH STRONGER
STORM PASSING WEST OF NEW ENGLAND WILL BRING HEAVY RAINFALL...
GUSTY WINDS AND COASTAL FLOODING CONCERNS TO THE REGION WEDNESDAY
AND WEDNESDAY NIGHT. DRY BUT VERY WINDY CONDITIONS FOLLOW FOR
CHRISTMAS DAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
1 PM UPDATE...WIDESPREAD LIGHT SNOW SHOWERS CONTINUE ACROSS
SOUTHERN NEW ENGLAND. SNOW IS LIGHT AND WITH TEMPERATURES AT OR
JUST ABOVE FREEZING...SNOW IS NOT ACCUMULATING ON PAVEMENT MOST
LOCATIONS AND IN SOME PLACES...NOT EVEN ON THE GRASS. SHOWERS ARE
TAKING THE FORM OF RAIN ACROSS PORTIONS OF PLYMOUTH COUNTY AS WELL
AS THE CAPE AND ISLANDS.

THE SHORTWAVE IS MOVING INTO NORTHERN NEW ENGLAND NOW SO EXPECT
SHOWERS TO BECOME MORE SCATTERED IN NATURE. HOWEVER...THERE IS
QUITE A BIT OF LOW LEVEL MOISTURE AND ENOUGH LIFT THAT SHOWERS
WILL CONTINUE.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...
TONIGHT...

A RATHER CLOUDY AND RAW NIGHT ACROSS SOUTHERN NEW ENGLAND.  WHILE
THERE IS NOT A SIGNIFICANT SHORTWAVE TO TRIGGER A LOT OF
PRECIPITATION...PLENTY OF LOW LEVEL MOISTURE/WEAK SHALLOW LIFT
REMAINS.  THIS MAY BE ENOUGH TO RESULT IN A FEW RAIN/SNOW SHOWER
FROM TIME TO TIME.  PTYPE...WOULD BE MAINLY SNOW SHOWERS EXCEPT TO
THE SOUTHEAST OF A NEWPORT...TO TAUNTON...TO JUST NORTH OF
MARSHFIELD LINE.  AGAIN...MUCH OF THE NIGHT WILL PROBABLY END UP
DRY...BUT JUST THE RISK FOR A FEW RAIN/SNOW SHOWERS.

&&

.LONG TERM /MONDAY THROUGH SUNDAY/...
HIGHLIGHTS...

* WEAK SHORTWAVE ON MON NIGHT/TUESDAY COULD BRING WINTRY
  MIX/FREEZING RAIN TO THE INTERIOR
* ANOMALOUS SYSTEM ACROSS THE GREAT LAKES WILL BRING HEAVY
  RAIN...GUSTY WINDS AND COASTAL FLOODING CONCERNS AROUND CHRISTMAS
  EVE
* BLUSTERY BUT AIRMASS WILL BE DRYING OUT ON CHRISTMAS DAY

OVERVIEW...

THE MODELS AND ENSEMBLES OFFER A REASONABLY SIMILAR AND PREDICTABLE
LARGER SCALE MID TO UPPER LEVEL PATTERN EVOLUTION FOR MUCH OF THE
UPCOMING WEEK. THIS ACTIVE FLOW REGIME DEVELOPS SEVERAL MID-UPPER
LEVEL TROUGH AND ASSOCIATED/UNSETTLING LEAD SURFACE LOW/FRONTAL
SYSTEMS AND PCPN SWATHS PROGRESS STEADILY ACROSS THE LOWER 48. THE
FIRST AMPLIFIED/DEEP LEAD SYSTEM WORKS ACROSS THE ERN/NERN US INTO
ERN CANADA CHRISTMAS EVE INTO CHRISTMAS ALLOWING FOR A MOIST/WARMED
AIRMASS IN ADVANCE OF FRONTAL APPROACH WITH HEAVIEST LEAD QPF
POTENTIAL OVER NEW ENGLAND. BIGGEST QUESTION IS THE EVOLUTION OF THE
SECONDARY LOW PRESSURE SYSTEM. 00Z GUIDANCE HAS BACKED OFF ON THE
STRENGTH OF THE LOW AND IS HAVING ISSUES ON HOW TO HANDLE ITS
EVOLUTION. THE EC AND GFS HAVE SLOWED DOWN THE SYSTEM SLIGHTLY WITH
THE EC HAVING MORE OF A NEGATIVE TROUGH VS THE GFS. BELIEVE THE
UKMET IS A GOOD COMPROMISE AT IS WAS THE FIRST DETERMINISTIC
GUIDANCE ON TAMPERING DOWN THE FIRST MAIN LOW...WHILE THE CMC IS OUT
TO LUNCH. REGARDLESS THIS IS A VERY ANOMALOUS SYSTEM THAT IS ABOUT 4
STANDARD DEVIATIONS AWAY.

A SECONDARY SYSTEM DEEPENS ACROSS THE FOUR CORNERS ON FRIDAY AND
WITH THE STUBBORN TROUGH OVER THE CENTRAL U.S...IT WILL PUSH A
SYSTEM TOWARDS SOUTHERN NEW ENGLAND BY SUNDAY. THIS SYSTEM MAY
SUPPORT A MODEST SWATH OF OVERRUNNING SNOW OVER SOUTHERN NEW
ENGLAND.

DETAILS...

MONDAY INTO TUESDAY...MODERATE CONFIDENCE.

A WEAK WAVE OF LOW PRESSURE DEVELOPS ALONG THE SOUTHEAST COAST
MONDAY...AND WILL BE ON A DEVELOPING WARM FRONTAL BOUNDARY. THIS LOW
REMAINS WEAK AS THE WARM FRONT MOVES SLOWLY NORTH MONDAY NIGHT INTO
TUESDAY. APPEARS THAT THERE IS DECENT WARM ADVECTION AHEAD OF THIS
WAVE. SEVERAL HI-RES GUIDANCE MODELS SHOW THAT THERE IS THE
POTENTIAL FOR COLD AIR DAMMING ACROSS THE INTERIOR INTO TUESDAY.
BIGGEST QUESTION WILL BE IS THERE ENOUGH MOISTURE FOR PRECIP DURING
THIS TIME FRAME. DUE TO A STRENGTHENING LLJ PROVIDING A GOOD SOURCE OF
LIFT ANTICIPATE PRECIP TO DEVELOP AND OVERSPREAD ACROSS SOUTHERN NEW
ENGLAND. IF THIS PLAYS OUT WITH COLD AIR DAMMING AND WARM AIR
ADVECTION...THEN WE COULD SEE FREEZING RAIN/DRIZZLE ACROSS THE I-91
CORRIDOR LATE MONDAY INTO TUESDAY MORNING. DURING THE DAY ON
TUESDAY...GOOD AMOUNT OF WARM AIR WILL PUSH SURFACE TEMPS ABOVE
FREEZING BY THE LATE MORNING ALLOWING FOR ANY PRECIP TO BE MORE OF
THE LIQUID VARIETY AHEAD OF THE CHRISTMAS EVE STORM. HOWEVER
GUIDANCE IS ALWAYS TOO FAST IN SCOURING TEMPS OUT ESP ACROSS THE CT
VALLEY SO WE WILL NEED TO MONITOR THIS CLOSELY...ESP DUE TO LIGHT
WINDS AND THE HIGH IN EASTERN CANADA. A WINTER WX ADVISORY MAY BE
NEEDED FOR THE LIGHT ICING POTENTIAL.

WE COULD ALSO SEE SOME MINOR COASTAL FLOODING CONCERNS ON TUESDAY. SEE
BELOW FOR MORE DETAILS.

WEDNESDAY INTO THURSDAY...HIGH CONFIDENCE IN SYSTEM LOW CONFIDENCE
ON DETAILS.

ANOMALOUS SYSTEM WILL STRENGTHEN OVER THE GREAT LAKES TUESDAY INTO
WEDNESDAY. A SECONDARY SHORTWAVE WILL ROUND THE DEEP TROUGH AND
DEVELOP A SECONDARY LOW PRESSURE ALONG THE COLD FRONT. THIS
SECONDARY LOW WILL STRENGTHEN AND PASS WEST OF SOUTHERN NEW ENGLAND.
THIS SYSTEM WILL CONTINUE TO DEEPEN AS IT MOVES TOWARDS EASTERN
CANADA SWINGING A COLD FRONT ACROSS THE NORTHEAST.

STRONG SOUTHERLY JET OUT AHEAD OF THE FRONT WITH A GULF MOISTURE
CONNECTION WILL IMPACT SOUTHERN NEW ENGLAND ON CHRISTMAS EVE. THIS
STRONG JET WILL YIELD FOR PCPN IN THE LIQUID VARIETY.  PW ANOMALIES
ARE BETWEEN +4 TO +5 STANDARD DEVIATIONS ABOVE NORMAL WHICH IS QUITE
ANOMALOUS FOR THIS TIME OF YEAR. IN FACT CURRENT PWATS ARE PROGGED
ABOVE 1.6 INCHES WITH MODEL QPF OVER 2 INCHES...AT THE VERY LEAST
COULD SEE URBAN AND POOR DRAINAGE FLOODING. LATEST EC EVEN SHOWS
OVER 2.5 INCHES OF QPF...AND WITH THE TROPICAL CONNECTION AND STRONG
SOUTHERLY FLOW COULD SEE HIGHER AMOUNTS DUE TO TOPOGRAPHY
ENHANCEMENTS. RAINFALL RECORDS MAY FALL IF EVERYTHING FALLS INTO
PLACE.

AHEAD OF THE FRONT...SOUTHERN NEW ENGLAND WILL WARM SECTOR WED INTO
THUR MORNING ALLOWING FOR TEMPERATURES TO BE WELL ABOVE AVERAGE. IN
FACT WE MAY BE CLOSE AT BREAKING RECORD HIGH TEMPS IF TEMPS WARM TO
60F OR ABOVE ON CHRISTMAS EVE. SINCE WE WILL BE IN THE WARM
SECTOR...AND SHOWALTERS CLOSE TO ZERO...ISOLATED THUNDER IS STILL
POSSIBLE.

STRONG LOW LEVEL WINDS WILL ALSO BE A CONCERN ESPECIALLY WEDNESDAY
NIGHT. THE ECMWF SHOWS EAST-SOUTHEAST WINDS 30-40 KNOTS ON WEDNESDAY
INCREASING TO 60-75 KNOTS BY WEDNESDAY NIGHT. STRONG DOWNPOURS MAY
OVERCOME THE LOW LEVEL INVERSION AND BRING STRONG GUSTS OF AT LEAST
30-40 KNOTS ESPECIALLY ALONG THE SOUTH COAST. A WIND ADVISORY MAY BE
NEEDED IN SOME AREAS.

CHRISTMAS DAY...MODERATE CONFIDENCE.

AS THE COLD FRONT PASSES THROUGH EARLY CHRISTMAS DAY...THE WEST
WINDS WILL HELP DRY THE AIRMASS ALLOWING FOR PARTLY SUNNY SKIES.
STRONG CAA ON THURSDAY WILL ALLOW DESCENT MIXING. WINDS IN THE SFC-
850 MB LAYER WILL BE 30-40 KNOTS AND POSSIBLY A LITTLE
HIGHER...WHICH WOULD REQUIRE A WIND ADVISORY FOR MUCH OF THE AREA.

FRIDAY-SUNDAY...LOWER CONFIDENCE

WEAK HIGH PRESSURE BUILDS OVER THE AREA FRIDAY INTO SATURDAY. THE
NEXT SHORTWAVE APPROACHES LATE SATURDAY INTO SUNDAY AND SHOULD BRING
INCREASING CLOUDS FROM WEST TO EAST ALONG WITH A CHANCE OF RAIN OR
SNOW SHOWERS MAINLY IN THE AFTERNOON AND AT NIGHT.

&&

.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /TODAY AND TONIGHT/...

MODERATE CONFIDENCE. MAINLY MVFR/IFR CONDITIONS THROUGH TONIGHT.
EXCEPTION RIGHT NOW IS THE CAPE AND ISLANDS WHERE VFR CONDITIONS
ARE IN PLACE. BELIEVE CONDITIONS WILL DETERIORATE LATER TONIGHT
THERE. WIDESPREAD LIGHT SNOW SHOWERS ARE AFFECTING ALL OF SOUTHERN
NEW ENGLAND THIS AFTERNOON. EXPECT THIS ACTIVITY TO BECOME MORE
SCATTERED IN NATURE. RAIN SHOWERS ACROSS MOST OF PLYMOUTH COUNTY
AND ONTO THE CAPE/ISLANDS WITH SNOW SHOWERS NORTH AND WEST.

KBOS TERMINAL...MODERATE CONFIDENCE.

KBDL TERMINAL...MODERATE CONFIDENCE.

OUTLOOK...MONDAY THROUGH THURSDAY...MODERATE CONFIDENCE.

MONDAY...MVFR CIGS CONTINUE IN RI/EASTERN MASS IN MARINE EAST FLOW.
VFR IN THE WEST.

TUESDAY...VFR WITH SCATTERED MVFR IN ANY RAIN/SNOW SHOWERS.

WEDNESDAY...CONDITIONS LOWERING TO IFR IN RAIN/HEAVY RAIN. ISOLATED
THUNDERSTORMS POSSIBLE ESPECIALLY WEDNESDAY NIGHT. EAST-SOUTHEAST
SURFACE WINDS MAY GUST TO 35-45 KNOTS. WINDS AT 2000 FEET AGL WILL
REACH 50-60 KNOTS WEDNESDAY AFTERNOON AND EARLY NIGHT CREATING LOW
LEVEL WIND SHEAR CONCERNS.

CHRISTMAS DAY...WEST WIND GUSTING 30-40 KNOTS. CONDITIONS IMPROVING
TO VFR AS THE WIND BRINGS IN COOLER DRIER AIR.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /TODAY AND TONIGHT/...HIGH CONFIDENCE.

HIGH PRESSURE ACROSS QUEBEC WILL RESULT IN NORTHEAST WINDS ACROSS
THE WATERS THAT WILL GUST TO BETWEEN 15 AND 20 KNOTS.  THIS WILL
RESULT IN 2 TO 4 FOOT SEAS.  HOWEVER...NO HEADLINES PLANNED AS
CONDITIONS SHOULD REMAIN BELOW SMALL CRAFT ADVISORY THRESHOLDS.

OUTLOOK...MONDAY THROUGH THURSDAY...MODERATE CONFIDENCE

MONDAY...EAST TO NORTHEAST WINDS GUSTING AROUND 15 KNOTS OR LESS.
SEAS WILL HOLD AROUND 3-4 FEET...MAY INCREASE TO 5FT IN NORTHEAST
FLOW AS GUIDANCE MAY BE UNDERDONE.

TUESDAY... INCREASING EAST WINDS WITH FREQUENT GUSTS 25 TO 30 KNOTS.
SEAS WILL BUILD TO 5-6 FEET ON THE EXPOSED WATERS.  A SMALL CRAFT
ADVISORY MAY BE NEEDED.

WEDNESDAY...RAIN WILL BE HEAVY AT TIMES PRODUCING POOR VISIBILITY.
INCREASING SOUTHEAST WINDS 20-25 SUSTAINED AND 40 KNOT GUSTS.  WINDS
SHOULD SHIFT TO SOUTH WEDNESDAY NIGHT AND SOUTHWEST TOWARD THURSDAY
MORNING. RAIN WILL TAPER OFF WITH THE WIND SHIFT TO SOUTHWEST. SEAS
WILL CONTINUE TO BUILD WITH 7-11 FEET HEIGHTS ON THE EXPOSED WATERS.
A GALE WARNING WILL BE NEEDED...WITH A LOW PROB OF A FEW STORM FORCE
GUSTS ACROSS THE EASTERN OUTER WATERS.

CHRISTMAS DAY... WEST SOUTHWEST WINDS WILL CONTINUE TO GUST 35-40
KNOTS...SO A CONTINUED GALE WARNING MAY BE NEEDED. SEAS OF 7-15 FEET
ARE POSSIBLE ON THE EXPOSED WATERS...AND 5 FEET IS POSSIBLE ON SOME
OF THE NEARSHORE WATERS.

&&

.TIDES/COASTAL FLOODING...
HIGH ASTRONOMICAL TIDES WILL OCCUR TUESDAY THROUGH THURSDAY. BREAKING
IT DOWN...ON TUESDAY HIGH TIDE AT BOSTON WILL BE 11.6 FT. THERE WILL
BE ONSHORE FLOW DURING THIS HIGH TIDE ALLOWING FOR MINOR SPLASHOVER.
IF WIND GUSTS INCREASE THEN COULD POSSIBLE SEE MINOR COASTAL
FLOODING.

ON WEDNESDAY...WINDS WILL SWITCH TO A MORE SOUTHEASTERLY FLOW DURING
THE DAY AND INCREASE QUICKLY FROM APPROACHING SYSTEM AND DECENT
PRESSURE FALLS. WEDNESDAY AFTERNOON HIGH TIDE IN BOSTON IS 11.7 FT
AND WITH ANY STRENGTH ON THE EASTERLY WIND FLOW WILL PUSH THE TIDE
OVER. RIGHT NOW BELIEVE MINOR COASTAL FLOODING IS POSSIBLE ALONG THE
EAST COASTLINE.

WEDNESDAY EVENING...THE WIND GOES IN A MORE SOUTHERLY DIRECTION AND
THE TIDE WILL BE INCREASE ACROSS THE SOUTH COAST. HIGH TIDE IN
PROVIDENCE WILL BE 5.2 FT. 925 MB LLJ STRENGTHENS TO 50-60 KTS WHICH
COULD PUSH A DECENT SURGE UP ALONG THE SOUTH COAST DURING THE TIME
OF HIGH TIDE. THINKING THAT MINOR COASTAL FLOODING COULD OCCUR BUT
CANNOT RULE OUT MODERATE ALONG THE SOUTH COAST...ESP IF LLJ
STRENGTHENS EVEN MORE.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...FRANK/DUNTEN
NEAR TERM...RLG
SHORT TERM...FRANK
LONG TERM...DUNTEN
AVIATION...DUNTEN/RLG
MARINE...FRANK/DUNTEN
TIDES/COASTAL FLOODING...




000
FXUS61 KBOX 211801
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
101 PM EST SUN DEC 21 2014

.SYNOPSIS...
SCATTERED SNOW/RAIN SHOWERS CONTINUE THROUGH THIS AFTERNOON. WEAK
LOW PRESSURE WILL PASS SOUTH OF NEW ENGLAND BRINGING ANOTHER
PERIOD OF PRECIPITATION MONDAY NIGHT AND TUESDAY. A MUCH STRONGER
STORM PASSING WEST OF NEW ENGLAND WILL BRING HEAVY RAINFALL...
GUSTY WINDS AND COASTAL FLOODING CONCERNS TO THE REGION WEDNESDAY
AND WEDNESDAY NIGHT. DRY BUT VERY WINDY CONDITIONS FOLLOW FOR
CHRISTMAS DAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
1 PM UPDATE...WIDESPREAD LIGHT SNOW SHOWERS CONTINUE ACROSS
SOUTHERN NEW ENGLAND. SNOW IS LIGHT AND WITH TEMPERATURES AT OR
JUST ABOVE FREEZING...SNOW IS NOT ACCUMULATING ON PAVEMENT MOST
LOCATIONS AND IN SOME PLACES...NOT EVEN ON THE GRASS. SHOWERS ARE
TAKING THE FORM OF RAIN ACROSS PORTIONS OF PLYMOUTH COUNTY AS WELL
AS THE CAPE AND ISLANDS.

THE SHORTWAVE IS MOVING INTO NORTHERN NEW ENGLAND NOW SO EXPECT
SHOWERS TO BECOME MORE SCATTERED IN NATURE. HOWEVER...THERE IS
QUITE A BIT OF LOW LEVEL MOISTURE AND ENOUGH LIFT THAT SHOWERS
WILL CONTINUE.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...
TONIGHT...

A RATHER CLOUDY AND RAW NIGHT ACROSS SOUTHERN NEW ENGLAND.  WHILE
THERE IS NOT A SIGNIFICANT SHORTWAVE TO TRIGGER A LOT OF
PRECIPITATION...PLENTY OF LOW LEVEL MOISTURE/WEAK SHALLOW LIFT
REMAINS.  THIS MAY BE ENOUGH TO RESULT IN A FEW RAIN/SNOW SHOWER
FROM TIME TO TIME.  PTYPE...WOULD BE MAINLY SNOW SHOWERS EXCEPT TO
THE SOUTHEAST OF A NEWPORT...TO TAUNTON...TO JUST NORTH OF
MARSHFIELD LINE.  AGAIN...MUCH OF THE NIGHT WILL PROBABLY END UP
DRY...BUT JUST THE RISK FOR A FEW RAIN/SNOW SHOWERS.

&&

.LONG TERM /MONDAY THROUGH SUNDAY/...
HIGHLIGHTS...

* WEAK SHORTWAVE ON MON NIGHT/TUESDAY COULD BRING WINTRY
  MIX/FREEZING RAIN TO THE INTERIOR
* ANOMALOUS SYSTEM ACROSS THE GREAT LAKES WILL BRING HEAVY
  RAIN...GUSTY WINDS AND COASTAL FLOODING CONCERNS AROUND CHRISTMAS
  EVE
* BLUSTERY BUT AIRMASS WILL BE DRYING OUT ON CHRISTMAS DAY

OVERVIEW...

THE MODELS AND ENSEMBLES OFFER A REASONABLY SIMILAR AND PREDICTABLE
LARGER SCALE MID TO UPPER LEVEL PATTERN EVOLUTION FOR MUCH OF THE
UPCOMING WEEK. THIS ACTIVE FLOW REGIME DEVELOPS SEVERAL MID-UPPER
LEVEL TROUGH AND ASSOCIATED/UNSETTLING LEAD SURFACE LOW/FRONTAL
SYSTEMS AND PCPN SWATHS PROGRESS STEADILY ACROSS THE LOWER 48. THE
FIRST AMPLIFIED/DEEP LEAD SYSTEM WORKS ACROSS THE ERN/NERN US INTO
ERN CANADA CHRISTMAS EVE INTO CHRISTMAS ALLOWING FOR A MOIST/WARMED
AIRMASS IN ADVANCE OF FRONTAL APPROACH WITH HEAVIEST LEAD QPF
POTENTIAL OVER NEW ENGLAND. BIGGEST QUESTION IS THE EVOLUTION OF THE
SECONDARY LOW PRESSURE SYSTEM. 00Z GUIDANCE HAS BACKED OFF ON THE
STRENGTH OF THE LOW AND IS HAVING ISSUES ON HOW TO HANDLE ITS
EVOLUTION. THE EC AND GFS HAVE SLOWED DOWN THE SYSTEM SLIGHTLY WITH
THE EC HAVING MORE OF A NEGATIVE TROUGH VS THE GFS. BELIEVE THE
UKMET IS A GOOD COMPROMISE AT IS WAS THE FIRST DETERMINISTIC
GUIDANCE ON TAMPERING DOWN THE FIRST MAIN LOW...WHILE THE CMC IS OUT
TO LUNCH. REGARDLESS THIS IS A VERY ANOMALOUS SYSTEM THAT IS ABOUT 4
STANDARD DEVIATIONS AWAY.

A SECONDARY SYSTEM DEEPENS ACROSS THE FOUR CORNERS ON FRIDAY AND
WITH THE STUBBORN TROUGH OVER THE CENTRAL U.S...IT WILL PUSH A
SYSTEM TOWARDS SOUTHERN NEW ENGLAND BY SUNDAY. THIS SYSTEM MAY
SUPPORT A MODEST SWATH OF OVERRUNNING SNOW OVER SOUTHERN NEW
ENGLAND.

DETAILS...

MONDAY INTO TUESDAY...MODERATE CONFIDENCE.

A WEAK WAVE OF LOW PRESSURE DEVELOPS ALONG THE SOUTHEAST COAST
MONDAY...AND WILL BE ON A DEVELOPING WARM FRONTAL BOUNDARY. THIS LOW
REMAINS WEAK AS THE WARM FRONT MOVES SLOWLY NORTH MONDAY NIGHT INTO
TUESDAY. APPEARS THAT THERE IS DECENT WARM ADVECTION AHEAD OF THIS
WAVE. SEVERAL HI-RES GUIDANCE MODELS SHOW THAT THERE IS THE
POTENTIAL FOR COLD AIR DAMMING ACROSS THE INTERIOR INTO TUESDAY.
BIGGEST QUESTION WILL BE IS THERE ENOUGH MOISTURE FOR PRECIP DURING
THIS TIME FRAME. DUE TO A STRENGTHENING LLJ PROVIDING A GOOD SOURCE OF
LIFT ANTICIPATE PRECIP TO DEVELOP AND OVERSPREAD ACROSS SOUTHERN NEW
ENGLAND. IF THIS PLAYS OUT WITH COLD AIR DAMMING AND WARM AIR
ADVECTION...THEN WE COULD SEE FREEZING RAIN/DRIZZLE ACROSS THE I-91
CORRIDOR LATE MONDAY INTO TUESDAY MORNING. DURING THE DAY ON
TUESDAY...GOOD AMOUNT OF WARM AIR WILL PUSH SURFACE TEMPS ABOVE
FREEZING BY THE LATE MORNING ALLOWING FOR ANY PRECIP TO BE MORE OF
THE LIQUID VARIETY AHEAD OF THE CHRISTMAS EVE STORM. HOWEVER
GUIDANCE IS ALWAYS TOO FAST IN SCOURING TEMPS OUT ESP ACROSS THE CT
VALLEY SO WE WILL NEED TO MONITOR THIS CLOSELY...ESP DUE TO LIGHT
WINDS AND THE HIGH IN EASTERN CANADA. A WINTER WX ADVISORY MAY BE
NEEDED FOR THE LIGHT ICING POTENTIAL.

WE COULD ALSO SEE SOME MINOR COASTAL FLOODING CONCERNS ON TUESDAY. SEE
BELOW FOR MORE DETAILS.

WEDNESDAY INTO THURSDAY...HIGH CONFIDENCE IN SYSTEM LOW CONFIDENCE
ON DETAILS.

ANOMALOUS SYSTEM WILL STRENGTHEN OVER THE GREAT LAKES TUESDAY INTO
WEDNESDAY. A SECONDARY SHORTWAVE WILL ROUND THE DEEP TROUGH AND
DEVELOP A SECONDARY LOW PRESSURE ALONG THE COLD FRONT. THIS
SECONDARY LOW WILL STRENGTHEN AND PASS WEST OF SOUTHERN NEW ENGLAND.
THIS SYSTEM WILL CONTINUE TO DEEPEN AS IT MOVES TOWARDS EASTERN
CANADA SWINGING A COLD FRONT ACROSS THE NORTHEAST.

STRONG SOUTHERLY JET OUT AHEAD OF THE FRONT WITH A GULF MOISTURE
CONNECTION WILL IMPACT SOUTHERN NEW ENGLAND ON CHRISTMAS EVE. THIS
STRONG JET WILL YIELD FOR PCPN IN THE LIQUID VARIETY.  PW ANOMALIES
ARE BETWEEN +4 TO +5 STANDARD DEVIATIONS ABOVE NORMAL WHICH IS QUITE
ANOMALOUS FOR THIS TIME OF YEAR. IN FACT CURRENT PWATS ARE PROGGED
ABOVE 1.6 INCHES WITH MODEL QPF OVER 2 INCHES...AT THE VERY LEAST
COULD SEE URBAN AND POOR DRAINAGE FLOODING. LATEST EC EVEN SHOWS
OVER 2.5 INCHES OF QPF...AND WITH THE TROPICAL CONNECTION AND STRONG
SOUTHERLY FLOW COULD SEE HIGHER AMOUNTS DUE TO TOPOGRAPHY
ENHANCEMENTS. RAINFALL RECORDS MAY FALL IF EVERYTHING FALLS INTO
PLACE.

AHEAD OF THE FRONT...SOUTHERN NEW ENGLAND WILL WARM SECTOR WED INTO
THUR MORNING ALLOWING FOR TEMPERATURES TO BE WELL ABOVE AVERAGE. IN
FACT WE MAY BE CLOSE AT BREAKING RECORD HIGH TEMPS IF TEMPS WARM TO
60F OR ABOVE ON CHRISTMAS EVE. SINCE WE WILL BE IN THE WARM
SECTOR...AND SHOWALTERS CLOSE TO ZERO...ISOLATED THUNDER IS STILL
POSSIBLE.

STRONG LOW LEVEL WINDS WILL ALSO BE A CONCERN ESPECIALLY WEDNESDAY
NIGHT. THE ECMWF SHOWS EAST-SOUTHEAST WINDS 30-40 KNOTS ON WEDNESDAY
INCREASING TO 60-75 KNOTS BY WEDNESDAY NIGHT. STRONG DOWNPOURS MAY
OVERCOME THE LOW LEVEL INVERSION AND BRING STRONG GUSTS OF AT LEAST
30-40 KNOTS ESPECIALLY ALONG THE SOUTH COAST. A WIND ADVISORY MAY BE
NEEDED IN SOME AREAS.

CHRISTMAS DAY...MODERATE CONFIDENCE.

AS THE COLD FRONT PASSES THROUGH EARLY CHRISTMAS DAY...THE WEST
WINDS WILL HELP DRY THE AIRMASS ALLOWING FOR PARTLY SUNNY SKIES.
STRONG CAA ON THURSDAY WILL ALLOW DESCENT MIXING. WINDS IN THE SFC-
850 MB LAYER WILL BE 30-40 KNOTS AND POSSIBLY A LITTLE
HIGHER...WHICH WOULD REQUIRE A WIND ADVISORY FOR MUCH OF THE AREA.

FRIDAY-SUNDAY...LOWER CONFIDENCE

WEAK HIGH PRESSURE BUILDS OVER THE AREA FRIDAY INTO SATURDAY. THE
NEXT SHORTWAVE APPROACHES LATE SATURDAY INTO SUNDAY AND SHOULD BRING
INCREASING CLOUDS FROM WEST TO EAST ALONG WITH A CHANCE OF RAIN OR
SNOW SHOWERS MAINLY IN THE AFTERNOON AND AT NIGHT.

&&

.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /TODAY AND TONIGHT/...

MODERATE CONFIDENCE. MAINLY MVFR/IFR CONDITIONS THROUGH TONIGHT.
EXCEPTION RIGHT NOW IS THE CAPE AND ISLANDS WHERE VFR CONDITIONS
ARE IN PLACE. BELIEVE CONDITIONS WILL DETERIORATE LATER TONIGHT
THERE. WIDESPREAD LIGHT SNOW SHOWERS ARE AFFECTING ALL OF SOUTHERN
NEW ENGLAND THIS AFTERNOON. EXPECT THIS ACTIVITY TO BECOME MORE
SCATTERED IN NATURE. RAIN SHOWERS ACROSS MOST OF PLYMOUTH COUNTY
AND ONTO THE CAPE/ISLANDS WITH SNOW SHOWERS NORTH AND WEST.

KBOS TERMINAL...MODERATE CONFIDENCE.

KBDL TERMINAL...MODERATE CONFIDENCE.

OUTLOOK...MONDAY THROUGH THURSDAY...MODERATE CONFIDENCE.

MONDAY...MVFR CIGS CONTINUE IN RI/EASTERN MASS IN MARINE EAST FLOW.
VFR IN THE WEST.

TUESDAY...VFR WITH SCATTERED MVFR IN ANY RAIN/SNOW SHOWERS.

WEDNESDAY...CONDITIONS LOWERING TO IFR IN RAIN/HEAVY RAIN. ISOLATED
THUNDERSTORMS POSSIBLE ESPECIALLY WEDNESDAY NIGHT. EAST-SOUTHEAST
SURFACE WINDS MAY GUST TO 35-45 KNOTS. WINDS AT 2000 FEET AGL WILL
REACH 50-60 KNOTS WEDNESDAY AFTERNOON AND EARLY NIGHT CREATING LOW
LEVEL WIND SHEAR CONCERNS.

CHRISTMAS DAY...WEST WIND GUSTING 30-40 KNOTS. CONDITIONS IMPROVING
TO VFR AS THE WIND BRINGS IN COOLER DRIER AIR.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /TODAY AND TONIGHT/...HIGH CONFIDENCE.

HIGH PRESSURE ACROSS QUEBEC WILL RESULT IN NORTHEAST WINDS ACROSS
THE WATERS THAT WILL GUST TO BETWEEN 15 AND 20 KNOTS.  THIS WILL
RESULT IN 2 TO 4 FOOT SEAS.  HOWEVER...NO HEADLINES PLANNED AS
CONDITIONS SHOULD REMAIN BELOW SMALL CRAFT ADVISORY THRESHOLDS.

OUTLOOK...MONDAY THROUGH THURSDAY...MODERATE CONFIDENCE

MONDAY...EAST TO NORTHEAST WINDS GUSTING AROUND 15 KNOTS OR LESS.
SEAS WILL HOLD AROUND 3-4 FEET...MAY INCREASE TO 5FT IN NORTHEAST
FLOW AS GUIDANCE MAY BE UNDERDONE.

TUESDAY... INCREASING EAST WINDS WITH FREQUENT GUSTS 25 TO 30 KNOTS.
SEAS WILL BUILD TO 5-6 FEET ON THE EXPOSED WATERS.  A SMALL CRAFT
ADVISORY MAY BE NEEDED.

WEDNESDAY...RAIN WILL BE HEAVY AT TIMES PRODUCING POOR VISIBILITY.
INCREASING SOUTHEAST WINDS 20-25 SUSTAINED AND 40 KNOT GUSTS.  WINDS
SHOULD SHIFT TO SOUTH WEDNESDAY NIGHT AND SOUTHWEST TOWARD THURSDAY
MORNING. RAIN WILL TAPER OFF WITH THE WIND SHIFT TO SOUTHWEST. SEAS
WILL CONTINUE TO BUILD WITH 7-11 FEET HEIGHTS ON THE EXPOSED WATERS.
A GALE WARNING WILL BE NEEDED...WITH A LOW PROB OF A FEW STORM FORCE
GUSTS ACROSS THE EASTERN OUTER WATERS.

CHRISTMAS DAY... WEST SOUTHWEST WINDS WILL CONTINUE TO GUST 35-40
KNOTS...SO A CONTINUED GALE WARNING MAY BE NEEDED. SEAS OF 7-15 FEET
ARE POSSIBLE ON THE EXPOSED WATERS...AND 5 FEET IS POSSIBLE ON SOME
OF THE NEARSHORE WATERS.

&&

.TIDES/COASTAL FLOODING...
HIGH ASTRONOMICAL TIDES WILL OCCUR TUESDAY THROUGH THURSDAY. BREAKING
IT DOWN...ON TUESDAY HIGH TIDE AT BOSTON WILL BE 11.6 FT. THERE WILL
BE ONSHORE FLOW DURING THIS HIGH TIDE ALLOWING FOR MINOR SPLASHOVER.
IF WIND GUSTS INCREASE THEN COULD POSSIBLE SEE MINOR COASTAL
FLOODING.

ON WEDNESDAY...WINDS WILL SWITCH TO A MORE SOUTHEASTERLY FLOW DURING
THE DAY AND INCREASE QUICKLY FROM APPROACHING SYSTEM AND DECENT
PRESSURE FALLS. WEDNESDAY AFTERNOON HIGH TIDE IN BOSTON IS 11.7 FT
AND WITH ANY STRENGTH ON THE EASTERLY WIND FLOW WILL PUSH THE TIDE
OVER. RIGHT NOW BELIEVE MINOR COASTAL FLOODING IS POSSIBLE ALONG THE
EAST COASTLINE.

WEDNESDAY EVENING...THE WIND GOES IN A MORE SOUTHERLY DIRECTION AND
THE TIDE WILL BE INCREASE ACROSS THE SOUTH COAST. HIGH TIDE IN
PROVIDENCE WILL BE 5.2 FT. 925 MB LLJ STRENGTHENS TO 50-60 KTS WHICH
COULD PUSH A DECENT SURGE UP ALONG THE SOUTH COAST DURING THE TIME
OF HIGH TIDE. THINKING THAT MINOR COASTAL FLOODING COULD OCCUR BUT
CANNOT RULE OUT MODERATE ALONG THE SOUTH COAST...ESP IF LLJ
STRENGTHENS EVEN MORE.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...FRANK/DUNTEN
NEAR TERM...RLG
SHORT TERM...FRANK
LONG TERM...DUNTEN
AVIATION...DUNTEN/RLG
MARINE...FRANK/DUNTEN
TIDES/COASTAL FLOODING...



000
FXUS61 KGYX 211655
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
1155 AM EST SUN DEC 21 2014

.SYNOPSIS...
HIGH PRESSURE BUILDS OVER NORTHERN MAINE SUNDAY...ALLOWING THE
FLOW TO TURN ONSHORE. A WEAK WEATHER DISTURBANCE MAY TRIGGER SOME
FLURRIES OR LIGHT SNOW OVER SOUTHERN REGIONS RIGHT THROUGH MONDAY.
A SIGNIFICANT LOW PRESSURE SYSTEM SYSTEM WILL GRADUALLY ORGANIZE
WEDNESDAY...BEFORE MOVING OVER THE GREAT LAKES. THIS COULD BRING
WINDY CONDITIONS AND THE POTENTIAL FOR HEAVY RAIN AROUND CHRISTMAS
EVE INTO EARLY CHRISTMAS MORNING.

&&

.NEAR TERM /THROUGH TONIGHT/...
NOON UPDATE...
LATEST RADAR IMAGERY CONTINUES TO SHOW AREA OF LIGHT SNOW
SPREADING SLOWLY TO THE NORTH. HOWEVER...PLENTY OF DRY AIR REMAINS
IN THE LOWEST LEVELS OF THE ATMOSPHERE AND SOME OF THIS PRECIP IS
SUBLIMATING BEFORE REACHING THE GROUND. WILL CONTINUE WITH HIGH
POPS OVER SOUTHERN SECTIONS...BUT ANY REMAINING SNOW THIS
AFTERNOON SHOULD BE VERY LIGHT...WITH JUST AN ADDITIONAL THIN
COATING OF SNOW IN SOME AREAS.

UPDATE...
HAVE UPDATED GRIDS TO RAISE POPS FROM SLIGHT CHANCE/CHANCE TO
CATEGORICAL...AT LEAST FOR THIS MORNING. LOW LEVEL MOISTURE
CONTINUES TO DEPOSIT SNOW ACROSS SOUTHERN NH AND FAR WESTERN
MAINE. WILL FORECAST 1 TO 2 INCHES OF SNOW FOR TODAY AS SOME AREAS
WILL REMAIN NEAR A MILE VSBY IN SNOW. SOME HIGHER REFLECTIVITY
RETURNS IN THE ROCHESTER NH AREA AS WELL WILL PINWHEEL SLOWLY TO
THE NE. THIS IS IN ASSOCIATION WITH AN INVERTED TROUGH OVER
SOUTHERN NEW ENGLAND AS OF 14Z WITH AN UPPER LEVEL LOW SLOWLY
CROSSING THE FORECAST AREA TODAY AS WELL. NUMERICAL MODELS SHIFT
PRECIP SOUTH AND EAST THIS AFTERNOON...WHICH IS IN DISAGREEMENT
WITH THE CURRENT RADAR ANIMATIONS.

OTHERWISE...JUST MINOR MODIFICATIONS TO THE REST OF THE GRIDED
PACKAGE.

PREV DISC...
615 AM UPDATE...JUST MADE SOME MINOR UPDATES TO SKY
AND TEMPERATURES BASED ON CURRENT OBS AND TRENDS...AS STRATUS
REMAINS ENTRENCHED ACROSS THE REGION.

PREVIOUS DISCUSSION...
LOW STRATUS BLANKETS THE CWFA AS A SURFACE HIGH PRESSURE IN
SOUTHERN QUEBEC IS HELPING TO KEEP MOISTURE TRAPPED IN THE LOW
LEVELS. A WEAK SHORTWAVE THAT IS PASSING OVER THE SOUTHERN NEW
ENGLAND THIS MORNING AND THIS MAY HELP KICK OFF SOME LIGHT SNOW
ACROSS THE FAR SOUTHERN AREAS OF NEW HAMPSHIRE AND PARTS OF
SOUTHWEST MAINE...AS ON SHORE FLOW SUPPLIES THE LOW LEVEL MOISTURE
THE LIFT FROM THIS WEAK SHORT MAY BE JUST ENOUGH TO PRODUCE SNOW
SHOWERS HEAVY ENOUGH TO ACCUMULATE IN SOME AREAS. AS THIS WEAK
WAVE MOVES EAST OUR FLOW...ALTHOUGH VERY WEAK...WILL TURN TO
NORTHWESTERLY AND THIS MAY BE ENOUGH TO START CLEARING OUT SOME OF
THE LOW STRATUS SUNDAY NIGHT.

&&

.SHORT TERM /MONDAY/...
FLOW WILL SWITCH BACK TO ON SHORE BY NOON ON MONDAY AND THIS WILL
BRING LIGHT OCEAN EFFECT SNOW OR MAYBE EVEN SOME LIGHT RAIN OR
EVEN FREEZING DRIZZLE INTO THE INTERIOR AS TEMPERATURES WILL HOVER
CLOSE TO FREEZING AS YOU GET AWAY FROM THE COAST.

&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
MODELS CONTINUE TO TREND TOWARD UPSTREAM AND DOWNSTREAM
BLOCKING...WITH AN EVENTUAL RETURN TO A +PNA PATTERN AT
500MB...WHICH WOULD SIGNAL COOLING LATE IN THE PERIOD. HOWEVER
ALL THE ACTION WILL BE IN DAYS 3 TO 5 AS THE UPSTREAM DEVELOPS AND
SENDS WAVES INTO TROUGH OVER CENTRAL CONUS...AMPLIFYING THE 500
MB FLOW.

INITIALLY...WILL BE DEALING WITH SMALLER SCALE FEATURE AS
INVERTED TROUGH OVER THE GULF OF ME WORK ITS WAY ONSHORE MON NIGHT
AND WEAKENS. MAY BE ENOUGH DYNAMIC FORCING FOR ICE CRYSTALS
INITIALLY...SO RAIN OR SNOW SHOWERS MOVE ONSHORE AND INLAND DURING
THE EVENING...BUT COULD SEE IT TURN TO DZ/FZDZ AS WE WE JUST
TRANSPORT WATER DROPLETS ONSHORE. WE MAINTAIN AN ONSHORE FLOW INTO
TUESDAY...BUT IT LOOKS LIKE FORCING WILL BE LIMITED TO
UPSLOPE...SO THINKING MORE IN THE WAY OF SHSN/SHRA/VERY LIGHT SNOW
INLAND...WITH JUST CLOUDS ON THE COAST. SHOULD SEE TEMPS ON TUE
WARM INTO THE UPPER 30S TO MID 40S.

THE MAIN EVENT REMAINS THE IMPRESSIVE 500 MB TROUGH THAT DEVELOPS
OVER THE CENTRAL CONUS MID WEEK...NOT SO MUCH IN THAT IT IS VERY
DEEP...BUT MORE ITS AMPLITUDE AS IT EXTENDS FROM N OF THE GREAT
LAKES SWD INTO THE GULF OF MEX....AND THEN TILTS VERY NEG AND
LIFTS POLEWARD WED NIGHT AND THU. NOT SURE HOW MUCH AN EFFECT
CONVECTIVE SCALING ISSUES ARE HAVING ON THE MODELS...BUT IT MAY BE
HAVING SOME EFFECT ON THE FORECAST DETAILS...BUT PROB NOT THE
GENERALITIES OF THE FORECAST. HOWEVER...00Z EURO AND GFS BOTH SHOW
A WEAKER SFC LOW IN THE VCNITY OF THE GRT LAKES AND ST LAWRENCE
VLY /ALTHOUGH IT DOES INTENSIFY FURTHER N AND E THAN PREV MODEL
RUNS. STILL...AS THAT WAVE LIFTS NWD WILL SEE TRIPLE POINT DEVELOP
OVER THE MID ATLANTIC WED EVE...AND LIFT NNE INTO THE CWA BY THU
MORNING. THIS WILL CREATE A DEEP SOUTHERLY FLOW WHICH WILL CONNECT
WITH GULF MOISTURE...ALLOWING FOR SIGNIFICANT RAINFALL...FROM
LATE IN THE DAY WED...INTO EARLY THU MORNING. QPF LOOKS TO RUN
AROUND 2-3 INCHES IN MANY SPOTS...BUT S-SE UPSLOPE AREAS OF THE
FOOTHILLS AND MTNS COULD SEE AN INCH OR TWO MORE...SO THE THREAT
OF BOTH FLASH AND MAINSTEM FLOODING IS A CONCERN...ESPECIALLY
SINCE THIS WILL BE COMBINE WITH SIGNIFICANT SNOWMELT AS HIGHS
RISE WELL INTO THE 40S WED..AND WILL LKLY STAY THERE WED NIGHT
INTO THU.

THERE IS STILL THE POTENTIAL FOR SOME STRONG GUSTS...BUT GIVEN
WEAKER SYSTEM...THE WINDOW FOR OPPORTUNITY WILL BE LIMITED TO A
FE HOURS AHEAD OF THE TRIPLE POINT PASSAGE...WHICH LOOKS TO BE WED
EVE...AT LEAST FOR NOW. WITH ALL THAT SAID...WE ARE STILL DEALING
WITH DAYS 4 AND 5 OF THE FORECAST...WITH THE POTENTIAL FRO SOME
DEEP CONVECTION IN THE BASE OF THE TROUGH...SO FORECAST COULD
CHANGE...BUT BOTH EURO AND GFS PICKED UP THE SIGNALS OF THIS
SYSTEM EARLY...AND HAVE BEEN CONSISTENT ON THE WHOLE SO FAR.

CHRISTMAS DAY WILL SEE RAIN ENDING FROM SW TO NE DURING THE
MORNING...WITH SOME PARTIAL CLEARING POSSIBLE IN THE
AFTERNOON...AND TEMPS IN THE 40S AGAIN. COOLER AIR WILL MOVE IN
FROM THE SW THU NIGHT. FRI AND SAT LOOK MOSTLY DRY /OTHER THAN
POSSIBLE UPSLOPE SHSN ON FRI/. HIGHS WILL CONTINUE TO RUN A FEW
DEGREES ABV NORMAL.

&&

.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
SHORT TERM...MVFR TO IFR CEILINGS WILL REMAIN OVER THE REGION
THROUGH AT LEAST SUNDAY EVENING. CONDITIONS MAY IMPROVE A BIT
SUNDAY NIGHT AS THE ON SHORE FLOW DRIFTING MOISTURE INLAND WILL
GET SHUT OFF. CONDITIONS WILL NOT STAY UP LONG HOWEVER AS THE FLOW
WILL SWITCH BACK TO ON SHORE ON MONDAY BRINGING ANOTHER ROUND OF
MVFR TO IFR CEILINGS.

LONG TERM...POSSIBLE PERIODS OF MVFR TO IFR MONDAY NIGHT AS
INVERTED TROUGH MOVES INLAND. MVFR LIKELY TO HOLD TUESDAY INTO
TUESDAY NIGHT...LOWERING TO IFR LATE TUESDAY NIGHT INTO THURSDAY
MORNING IN RAIN...WITH INCREASING E-SE WINDS WEDNESDAY.

&&

.MARINE...
SHORT TERM...A FEW WIND GUSTS CONTINUE JUST BELOW 25 KTS THIS
AFTERNOON...WITH WAVES 4` OR LOWER...THEREFORE NO FLAGS IN THE
NEAR TERM. WINDS SHOULD CONTINUE TO SLOWLY DECREASE TONIGHT INTO
TOMORROW FROM THE NORTHEAST.

LONG TERM...HIGH PRESSURE WITH LIGHT AND FAIRLY CALM SEAS WILL
PERSIST THROUGH THE PERIOD AND NO FLAGS ARE EXPECTED.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.

&&

$$




000
FXUS61 KGYX 211655
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
1155 AM EST SUN DEC 21 2014

.SYNOPSIS...
HIGH PRESSURE BUILDS OVER NORTHERN MAINE SUNDAY...ALLOWING THE
FLOW TO TURN ONSHORE. A WEAK WEATHER DISTURBANCE MAY TRIGGER SOME
FLURRIES OR LIGHT SNOW OVER SOUTHERN REGIONS RIGHT THROUGH MONDAY.
A SIGNIFICANT LOW PRESSURE SYSTEM SYSTEM WILL GRADUALLY ORGANIZE
WEDNESDAY...BEFORE MOVING OVER THE GREAT LAKES. THIS COULD BRING
WINDY CONDITIONS AND THE POTENTIAL FOR HEAVY RAIN AROUND CHRISTMAS
EVE INTO EARLY CHRISTMAS MORNING.

&&

.NEAR TERM /THROUGH TONIGHT/...
NOON UPDATE...
LATEST RADAR IMAGERY CONTINUES TO SHOW AREA OF LIGHT SNOW
SPREADING SLOWLY TO THE NORTH. HOWEVER...PLENTY OF DRY AIR REMAINS
IN THE LOWEST LEVELS OF THE ATMOSPHERE AND SOME OF THIS PRECIP IS
SUBLIMATING BEFORE REACHING THE GROUND. WILL CONTINUE WITH HIGH
POPS OVER SOUTHERN SECTIONS...BUT ANY REMAINING SNOW THIS
AFTERNOON SHOULD BE VERY LIGHT...WITH JUST AN ADDITIONAL THIN
COATING OF SNOW IN SOME AREAS.

UPDATE...
HAVE UPDATED GRIDS TO RAISE POPS FROM SLIGHT CHANCE/CHANCE TO
CATEGORICAL...AT LEAST FOR THIS MORNING. LOW LEVEL MOISTURE
CONTINUES TO DEPOSIT SNOW ACROSS SOUTHERN NH AND FAR WESTERN
MAINE. WILL FORECAST 1 TO 2 INCHES OF SNOW FOR TODAY AS SOME AREAS
WILL REMAIN NEAR A MILE VSBY IN SNOW. SOME HIGHER REFLECTIVITY
RETURNS IN THE ROCHESTER NH AREA AS WELL WILL PINWHEEL SLOWLY TO
THE NE. THIS IS IN ASSOCIATION WITH AN INVERTED TROUGH OVER
SOUTHERN NEW ENGLAND AS OF 14Z WITH AN UPPER LEVEL LOW SLOWLY
CROSSING THE FORECAST AREA TODAY AS WELL. NUMERICAL MODELS SHIFT
PRECIP SOUTH AND EAST THIS AFTERNOON...WHICH IS IN DISAGREEMENT
WITH THE CURRENT RADAR ANIMATIONS.

OTHERWISE...JUST MINOR MODIFICATIONS TO THE REST OF THE GRIDED
PACKAGE.

PREV DISC...
615 AM UPDATE...JUST MADE SOME MINOR UPDATES TO SKY
AND TEMPERATURES BASED ON CURRENT OBS AND TRENDS...AS STRATUS
REMAINS ENTRENCHED ACROSS THE REGION.

PREVIOUS DISCUSSION...
LOW STRATUS BLANKETS THE CWFA AS A SURFACE HIGH PRESSURE IN
SOUTHERN QUEBEC IS HELPING TO KEEP MOISTURE TRAPPED IN THE LOW
LEVELS. A WEAK SHORTWAVE THAT IS PASSING OVER THE SOUTHERN NEW
ENGLAND THIS MORNING AND THIS MAY HELP KICK OFF SOME LIGHT SNOW
ACROSS THE FAR SOUTHERN AREAS OF NEW HAMPSHIRE AND PARTS OF
SOUTHWEST MAINE...AS ON SHORE FLOW SUPPLIES THE LOW LEVEL MOISTURE
THE LIFT FROM THIS WEAK SHORT MAY BE JUST ENOUGH TO PRODUCE SNOW
SHOWERS HEAVY ENOUGH TO ACCUMULATE IN SOME AREAS. AS THIS WEAK
WAVE MOVES EAST OUR FLOW...ALTHOUGH VERY WEAK...WILL TURN TO
NORTHWESTERLY AND THIS MAY BE ENOUGH TO START CLEARING OUT SOME OF
THE LOW STRATUS SUNDAY NIGHT.

&&

.SHORT TERM /MONDAY/...
FLOW WILL SWITCH BACK TO ON SHORE BY NOON ON MONDAY AND THIS WILL
BRING LIGHT OCEAN EFFECT SNOW OR MAYBE EVEN SOME LIGHT RAIN OR
EVEN FREEZING DRIZZLE INTO THE INTERIOR AS TEMPERATURES WILL HOVER
CLOSE TO FREEZING AS YOU GET AWAY FROM THE COAST.

&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
MODELS CONTINUE TO TREND TOWARD UPSTREAM AND DOWNSTREAM
BLOCKING...WITH AN EVENTUAL RETURN TO A +PNA PATTERN AT
500MB...WHICH WOULD SIGNAL COOLING LATE IN THE PERIOD. HOWEVER
ALL THE ACTION WILL BE IN DAYS 3 TO 5 AS THE UPSTREAM DEVELOPS AND
SENDS WAVES INTO TROUGH OVER CENTRAL CONUS...AMPLIFYING THE 500
MB FLOW.

INITIALLY...WILL BE DEALING WITH SMALLER SCALE FEATURE AS
INVERTED TROUGH OVER THE GULF OF ME WORK ITS WAY ONSHORE MON NIGHT
AND WEAKENS. MAY BE ENOUGH DYNAMIC FORCING FOR ICE CRYSTALS
INITIALLY...SO RAIN OR SNOW SHOWERS MOVE ONSHORE AND INLAND DURING
THE EVENING...BUT COULD SEE IT TURN TO DZ/FZDZ AS WE WE JUST
TRANSPORT WATER DROPLETS ONSHORE. WE MAINTAIN AN ONSHORE FLOW INTO
TUESDAY...BUT IT LOOKS LIKE FORCING WILL BE LIMITED TO
UPSLOPE...SO THINKING MORE IN THE WAY OF SHSN/SHRA/VERY LIGHT SNOW
INLAND...WITH JUST CLOUDS ON THE COAST. SHOULD SEE TEMPS ON TUE
WARM INTO THE UPPER 30S TO MID 40S.

THE MAIN EVENT REMAINS THE IMPRESSIVE 500 MB TROUGH THAT DEVELOPS
OVER THE CENTRAL CONUS MID WEEK...NOT SO MUCH IN THAT IT IS VERY
DEEP...BUT MORE ITS AMPLITUDE AS IT EXTENDS FROM N OF THE GREAT
LAKES SWD INTO THE GULF OF MEX....AND THEN TILTS VERY NEG AND
LIFTS POLEWARD WED NIGHT AND THU. NOT SURE HOW MUCH AN EFFECT
CONVECTIVE SCALING ISSUES ARE HAVING ON THE MODELS...BUT IT MAY BE
HAVING SOME EFFECT ON THE FORECAST DETAILS...BUT PROB NOT THE
GENERALITIES OF THE FORECAST. HOWEVER...00Z EURO AND GFS BOTH SHOW
A WEAKER SFC LOW IN THE VCNITY OF THE GRT LAKES AND ST LAWRENCE
VLY /ALTHOUGH IT DOES INTENSIFY FURTHER N AND E THAN PREV MODEL
RUNS. STILL...AS THAT WAVE LIFTS NWD WILL SEE TRIPLE POINT DEVELOP
OVER THE MID ATLANTIC WED EVE...AND LIFT NNE INTO THE CWA BY THU
MORNING. THIS WILL CREATE A DEEP SOUTHERLY FLOW WHICH WILL CONNECT
WITH GULF MOISTURE...ALLOWING FOR SIGNIFICANT RAINFALL...FROM
LATE IN THE DAY WED...INTO EARLY THU MORNING. QPF LOOKS TO RUN
AROUND 2-3 INCHES IN MANY SPOTS...BUT S-SE UPSLOPE AREAS OF THE
FOOTHILLS AND MTNS COULD SEE AN INCH OR TWO MORE...SO THE THREAT
OF BOTH FLASH AND MAINSTEM FLOODING IS A CONCERN...ESPECIALLY
SINCE THIS WILL BE COMBINE WITH SIGNIFICANT SNOWMELT AS HIGHS
RISE WELL INTO THE 40S WED..AND WILL LKLY STAY THERE WED NIGHT
INTO THU.

THERE IS STILL THE POTENTIAL FOR SOME STRONG GUSTS...BUT GIVEN
WEAKER SYSTEM...THE WINDOW FOR OPPORTUNITY WILL BE LIMITED TO A
FE HOURS AHEAD OF THE TRIPLE POINT PASSAGE...WHICH LOOKS TO BE WED
EVE...AT LEAST FOR NOW. WITH ALL THAT SAID...WE ARE STILL DEALING
WITH DAYS 4 AND 5 OF THE FORECAST...WITH THE POTENTIAL FRO SOME
DEEP CONVECTION IN THE BASE OF THE TROUGH...SO FORECAST COULD
CHANGE...BUT BOTH EURO AND GFS PICKED UP THE SIGNALS OF THIS
SYSTEM EARLY...AND HAVE BEEN CONSISTENT ON THE WHOLE SO FAR.

CHRISTMAS DAY WILL SEE RAIN ENDING FROM SW TO NE DURING THE
MORNING...WITH SOME PARTIAL CLEARING POSSIBLE IN THE
AFTERNOON...AND TEMPS IN THE 40S AGAIN. COOLER AIR WILL MOVE IN
FROM THE SW THU NIGHT. FRI AND SAT LOOK MOSTLY DRY /OTHER THAN
POSSIBLE UPSLOPE SHSN ON FRI/. HIGHS WILL CONTINUE TO RUN A FEW
DEGREES ABV NORMAL.

&&

.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
SHORT TERM...MVFR TO IFR CEILINGS WILL REMAIN OVER THE REGION
THROUGH AT LEAST SUNDAY EVENING. CONDITIONS MAY IMPROVE A BIT
SUNDAY NIGHT AS THE ON SHORE FLOW DRIFTING MOISTURE INLAND WILL
GET SHUT OFF. CONDITIONS WILL NOT STAY UP LONG HOWEVER AS THE FLOW
WILL SWITCH BACK TO ON SHORE ON MONDAY BRINGING ANOTHER ROUND OF
MVFR TO IFR CEILINGS.

LONG TERM...POSSIBLE PERIODS OF MVFR TO IFR MONDAY NIGHT AS
INVERTED TROUGH MOVES INLAND. MVFR LIKELY TO HOLD TUESDAY INTO
TUESDAY NIGHT...LOWERING TO IFR LATE TUESDAY NIGHT INTO THURSDAY
MORNING IN RAIN...WITH INCREASING E-SE WINDS WEDNESDAY.

&&

.MARINE...
SHORT TERM...A FEW WIND GUSTS CONTINUE JUST BELOW 25 KTS THIS
AFTERNOON...WITH WAVES 4` OR LOWER...THEREFORE NO FLAGS IN THE
NEAR TERM. WINDS SHOULD CONTINUE TO SLOWLY DECREASE TONIGHT INTO
TOMORROW FROM THE NORTHEAST.

LONG TERM...HIGH PRESSURE WITH LIGHT AND FAIRLY CALM SEAS WILL
PERSIST THROUGH THE PERIOD AND NO FLAGS ARE EXPECTED.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.

&&

$$



000
FXUS61 KBOX 211452
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
952 AM EST SUN DEC 21 2014

.SYNOPSIS...
SCATTERED SNOW/RAIN SHOWERS CONTINUE THROUGH THIS AFTERNOON. WEAK
LOW PRESSURE WILL PASS SOUTH OF NEW ENGLAND BRINGING ANOTHER
PERIOD OF PRECIPITATION MONDAY NIGHT AND TUESDAY. A MUCH STRONGER
STORM PASSING WEST OF NEW ENGLAND WILL BRING HEAVY RAINFALL...
GUSTY WINDS AND COASTAL FLOODING CONCERNS TO THE REGION WEDNESDAY
AND WEDNESDAY NIGHT. DRY BUT VERY WINDY CONDITIONS FOLLOW FOR
CHRISTMAS DAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
10 AM UPDATE...SCATTERED SNOW SHOWERS CONTINUE ACROSS SOUTHERN NEW
ENGLAND THIS MORNING. MOST OF THESE ARE TOO LIGHT EVEN TO SHOW UP
ON RADAR BUT THEY ARE BEING REPORTED IN GROUND TRUTH REPORTS FROM
SOCIAL MEDIA AND THE PUBLIC.

PREVIOUS DISCUSSION...

THE RAIN/SNOW LINE RUNS ROUGHLY FROM NEWPORT...TO TAUNTON AND
JUST NORTH OF MARSHFIELD. OVERALL...DO NOT EXPECT MUCH CHANGE IN
THE RAIN/SNOW LINE THIS MORNING BASED ON THERMAL PROFILES AND
POSITIONING OF THE COASTAL FRONT.

MAIN UNCERTAINTY IS JUST HOW MUCH SNOW OCCURS THIS MORNING WITH THE
SHORTWAVE MOVING ACROSS CT.  GIVEN THE TRACK OF THE SHORTWAVE...BEST
FORCING WILL BE LOCATED SOUTH OF THE MA TURNPIKE AND ESPECIALLY
ACROSS NORTHERN CT/RI.  WE WILL FORECAST 1 TO 2 INCHES OF SNOW
ACROSS THIS REGION...BUT A FEW ISOLATED 3 INCH AMOUNTS CAN NOT BE
RULED OUT. MEANWHILE...AREAS NORTH OF THE MA TURNPIKE WILL BE
REMOVED FROM THE BEST FORCING...BUT STILL SEE SOME SCATTERED
SHOWERS.  ACCUMS IN THIS AREA LIKELY TO BE A DUSTING TO LESS THAN AN
INCH.

ALSO...SOME OF THE PRECIPITATION CURRENTLY ACROSS SOUTHEAST MA IS
BEING ENHANCED FROM THE COASTAL FRONT.  A LOT OF THIS PRECIP WILL
BE IN THE FORM OF RAIN SHOWERS ACROSS PLYMOUTH AND EVEN INTO
PORTIONS OF BRISTOL COUNTY...POINTS SOUTH AND EAST.  HOWEVER...AT
LEAST THE SLIGHTLY HIGHER TERRAIN OF SOUTHEAST MA SHOULD SEE SNOW
SHOWERS.  WILL HAVE TO KEEP A CLOSE EYE ON IF COASTAL FRONT SHIFTS
SLIGHTLY THIS MORNING.  IT COULD MEAN THE DIFFERENCE BETWEEN AN AREA
GETTING MAINLY RAIN SHOWERS OR PERHAPS AN INCH OR SO OF SNOW.
OVERALL...DO NOT EXPECT THE COASTAL FRONT TO MOVE TOO MUCH THIS
MORNING...BUT JUST A FEW MILES CAN MAKE DIFFERENCE FOR A
PARTICULARLY NEIGHBORHOOD.

BULK OF PRECIPITATION WILL BE THIS MORNING WITH THE SHORTWAVE.
HOWEVER...ENOUGH LOW LEVEL MOISTURE/WEAK LIFT WILL REMAIN THIS
AFTERNOON FOR AT LEAST THIS RISK OF SCATTERED PRECIPITATION AND WILL
MAINTAIN SOME POPS.  HIGH TEMPS MAINLY IN THE 30S.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...
TONIGHT...

A RATHER CLOUDY AND RAW NIGHT ACROSS SOUTHERN NEW ENGLAND.  WHILE
THERE IS NOT A SIGNIFICANT SHORTWAVE TO TRIGGER A LOT OF
PRECIPITATION...PLENTY OF LOW LEVEL MOISTURE/WEAK SHALLOW LIFT
REMAINS.  THIS MAY BE ENOUGH TO RESULT IN A FEW RAIN/SNOW SHOWER
FROM TIME TO TIME.  PTYPE...WOULD BE MAINLY SNOW SHOWERS EXCEPT TO
THE SOUTHEAST OF A NEWPORT...TO TAUNTON...TO JUST NORTH OF
MARSHFIELD LINE.  AGAIN...MUCH OF THE NIGHT WILL PROBABLY END UP
DRY...BUT JUST THE RISK FOR A FEW RAIN/SNOW SHOWERS.

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...
HIGHLIGHTS...

* WEAK SHORTWAVE ON MON NIGHT/TUESDAY COULD BRING WINTRY
  MIX/FREEZING RAIN TO THE INTERIOR
* ANOMALOUS SYSTEM ACROSS THE GREAT LAKES WILL BRING HEAVY
  RAIN...GUSTY WINDS AND COASTAL FLOODING CONCERNS AROUND CHRISTMAS
  EVE
* BLUSTERY BUT AIRMASS WILL BE DRYING OUT ON CHRISTMAS DAY

OVERVIEW...

THE MODELS AND ENSEMBLES OFFER A REASONABLY SIMILAR AND PREDICTABLE
LARGER SCALE MID TO UPPER LEVEL PATTERN EVOLUTION FOR MUCH OF THE
UPCOMING WEEK. THIS ACTIVE FLOW REGIME DEVELOPS SEVERAL MID-UPPER
LEVEL TROUGH AND ASSOCIATED/UNSETTLING LEAD SURFACE LOW/FRONTAL
SYSTEMS AND PCPN SWATHS PROGRESS STEADILY ACROSS THE LOWER 48. THE
FIRST AMPLIFIED/DEEP LEAD SYSTEM WORKS ACROSS THE ERN/NERN US INTO
ERN CANADA CHRISTMAS EVE INTO CHRISTMAS ALLOWING FOR A MOIST/WARMED
AIRMASS IN ADVANCE OF FRONTAL APPROACH WITH HEAVIEST LEAD QPF
POTENTIAL OVER NEW ENGLAND. BIGGEST QUESTION IS THE EVOLUTION OF THE
SECONDARY LOW PRESSURE SYSTEM. 00Z GUIDANCE HAS BACKED OFF ON THE
STRENGTH OF THE LOW AND IS HAVING ISSUES ON HOW TO HANDLE ITS
EVOLUTION. THE EC AND GFS HAVE SLOWED DOWN THE SYSTEM SLIGHTLY WITH
THE EC HAVING MORE OF A NEGATIVE TROUGH VS THE GFS. BELIEVE THE
UKMET IS A GOOD COMPROMISE AT IS WAS THE FIRST DETERMINISTIC
GUIDANCE ON TAMPERING DOWN THE FIRST MAIN LOW...WHILE THE CMC IS OUT
TO LUNCH. REGARDLESS THIS IS A VERY ANOMALOUS SYSTEM THAT IS ABOUT 4
STANDARD DEVIATIONS AWAY.

A SECONDARY SYSTEM DEEPENS ACROSS THE FOUR CORNERS ON FRIDAY AND
WITH THE STUBBORN TROUGH OVER THE CENTRAL U.S...IT WILL PUSH A
SYSTEM TOWARDS SOUTHERN NEW ENGLAND BY SUNDAY. THIS SYSTEM MAY
SUPPORT A MODEST SWATH OF OVERRUNNING SNOW OVER SOUTHERN NEW
ENGLAND.

DETAILS...

MONDAY INTO TUESDAY...MODERATE CONFIDENCE.

A WEAK WAVE OF LOW PRESSURE DEVELOPS ALONG THE SOUTHEAST COAST
MONDAY...AND WILL BE ON A DEVELOPING WARM FRONTAL BOUNDARY. THIS LOW
REMAINS WEAK AS THE WARM FRONT MOVES SLOWLY NORTH MONDAY NIGHT INTO
TUESDAY. APPEARS THAT THERE IS DECENT WARM ADVECTION AHEAD OF THIS
WAVE. SEVERAL HI-RES GUIDANCE MODELS SHOW THAT THERE IS THE
POTENTIAL FOR COLD AIR DAMMING ACROSS THE INTERIOR INTO TUESDAY.
BIGGEST QUESTION WILL BE IS THERE ENOUGH MOISTURE FOR PRECIP DURING
THIS TIME FRAME. DUE TO A STRENGTHENING LLJ PROVIDING A GOOD SOURCE OF
LIFT ANTICIPATE PRECIP TO DEVELOP AND OVERSPREAD ACROSS SOUTHERN NEW
ENGLAND. IF THIS PLAYS OUT WITH COLD AIR DAMMING AND WARM AIR
ADVECTION...THEN WE COULD SEE FREEZING RAIN/DRIZZLE ACROSS THE I-91
CORRIDOR LATE MONDAY INTO TUESDAY MORNING. DURING THE DAY ON
TUESDAY...GOOD AMOUNT OF WARM AIR WILL PUSH SURFACE TEMPS ABOVE
FREEZING BY THE LATE MORNING ALLOWING FOR ANY PRECIP TO BE MORE OF
THE LIQUID VARIETY AHEAD OF THE CHRISTMAS EVE STORM. HOWEVER
GUIDANCE IS ALWAYS TOO FAST IN SCOURING TEMPS OUT ESP ACROSS THE CT
VALLEY SO WE WILL NEED TO MONITOR THIS CLOSELY...ESP DUE TO LIGHT
WINDS AND THE HIGH IN EASTERN CANADA. A WINTER WX ADVISORY MAY BE
NEEDED FOR THE LIGHT ICING POTENTIAL.

WE COULD ALSO SEE SOME MINOR COASTAL FLOODING CONCERNS ON TUESDAY. SEE
BELOW FOR MORE DETAILS.

WEDNESDAY INTO THURSDAY...HIGH CONFIDENCE IN SYSTEM LOW CONFIDENCE
ON DETAILS.

ANOMALOUS SYSTEM WILL STRENGTHEN OVER THE GREAT LAKES TUESDAY INTO
WEDNESDAY. A SECONDARY SHORTWAVE WILL ROUND THE DEEP TROUGH AND
DEVELOP A SECONDARY LOW PRESSURE ALONG THE COLD FRONT. THIS
SECONDARY LOW WILL STRENGTHEN AND PASS WEST OF SOUTHERN NEW ENGLAND.
THIS SYSTEM WILL CONTINUE TO DEEPEN AS IT MOVES TOWARDS EASTERN
CANADA SWINGING A COLD FRONT ACROSS THE NORTHEAST.

STRONG SOUTHERLY JET OUT AHEAD OF THE FRONT WITH A GULF MOISTURE
CONNECTION WILL IMPACT SOUTHERN NEW ENGLAND ON CHRISTMAS EVE. THIS
STRONG JET WILL YIELD FOR PCPN IN THE LIQUID VARIETY.  PW ANOMALIES
ARE BETWEEN +4 TO +5 STANDARD DEVIATIONS ABOVE NORMAL WHICH IS QUITE
ANOMALOUS FOR THIS TIME OF YEAR. IN FACT CURRENT PWATS ARE PROGGED
ABOVE 1.6 INCHES WITH MODEL QPF OVER 2 INCHES...AT THE VERY LEAST
COULD SEE URBAN AND POOR DRAINAGE FLOODING. LATEST EC EVEN SHOWS
OVER 2.5 INCHES OF QPF...AND WITH THE TROPICAL CONNECTION AND STRONG
SOUTHERLY FLOW COULD SEE HIGHER AMOUNTS DUE TO TOPOGRAPHY
ENHANCEMENTS. RAINFALL RECORDS MAY FALL IF EVERYTHING FALLS INTO
PLACE.

AHEAD OF THE FRONT...SOUTHERN NEW ENGLAND WILL WARM SECTOR WED INTO
THUR MORNING ALLOWING FOR TEMPERATURES TO BE WELL ABOVE AVERAGE. IN
FACT WE MAY BE CLOSE AT BREAKING RECORD HIGH TEMPS IF TEMPS WARM TO
60F OR ABOVE ON CHRISTMAS EVE. SINCE WE WILL BE IN THE WARM
SECTOR...AND SHOWALTERS CLOSE TO ZERO...ISOLATED THUNDER IS STILL
POSSIBLE.

STRONG LOW LEVEL WINDS WILL ALSO BE A CONCERN ESPECIALLY WEDNESDAY
NIGHT. THE ECMWF SHOWS EAST-SOUTHEAST WINDS 30-40 KNOTS ON WEDNESDAY
INCREASING TO 60-75 KNOTS BY WEDNESDAY NIGHT. STRONG DOWNPOURS MAY
OVERCOME THE LOW LEVEL INVERSION AND BRING STRONG GUSTS OF AT LEAST
30-40 KNOTS ESPECIALLY ALONG THE SOUTH COAST. A WIND ADVISORY MAY BE
NEEDED IN SOME AREAS.

CHRISTMAS DAY...MODERATE CONFIDENCE.

AS THE COLD FRONT PASSES THROUGH EARLY CHRISTMAS DAY...THE WEST
WINDS WILL HELP DRY THE AIRMASS ALLOWING FOR PARTLY SUNNY SKIES.
STRONG CAA ON THURSDAY WILL ALLOW DESCENT MIXING. WINDS IN THE SFC-
850 MB LAYER WILL BE 30-40 KNOTS AND POSSIBLY A LITTLE
HIGHER...WHICH WOULD REQUIRE A WIND ADVISORY FOR MUCH OF THE AREA.

FRIDAY-SUNDAY...LOWER CONFIDENCE

WEAK HIGH PRESSURE BUILDS OVER THE AREA FRIDAY INTO SATURDAY. THE
NEXT SHORTWAVE APPROACHES LATE SATURDAY INTO SUNDAY AND SHOULD BRING
INCREASING CLOUDS FROM WEST TO EAST ALONG WITH A CHANCE OF RAIN OR
SNOW SHOWERS MAINLY IN THE AFTERNOON AND AT NIGHT.

&&

.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /TODAY AND TONIGHT/...

TODAY AND TONIGHT...MODERATE CONFIDENCE.  MAINLY MVFR CONDITIONS
SOUTH OF THE MA TURNPIKE WITH BORDERLINE VFR TO MARGINAL MVFR CIGS
NORTH OF THE PIKE THROUGH TONIGHT.  AN AREA OF SNOW SHOWERS WILL
EXPAND MAINLY ACROSS AREAS SOUTH OF THE PIKE THIS MORNING...BUT A
FEW SNOW SHOWERS WILL STILL AFFECT NORTHERN MA.  VSBYS/CIGS MAY
BRIEFLY DROP TO IFR LEVELS IN NORTHERN CT/RI/SE MA.  PTYPE WILL BE
RAIN SHOWERS ACROSS MOST OF PLYMOUTH COUNTY AND ONTO THE
CAPE/ISLANDS WITH SNOW SHOWERS NORTH AND WEST.  BULK OF PRECIP THIS
MORNING...BUT A FEW LINGERING RAIN/SNOW SHOWERS STILL POSSIBLE THIS
AFTERNOON AND EVENING.

KBOS TERMINAL...MODERATE CONFIDENCE.  A FEW SNOW SHOWERS POSSIBLE
THIS MORNING BUT BULK OF ACTIVITY SHOULD BE SOUTH OF THE TERMINAL.

KBDL TERMINAL...MODERATE CONFIDENCE.  PERIOD OF SNOW SHOWERS THIS
MORNING MAY DROP AN INCH OR TWO OF SNOW.  MVFR CONDITIONS DOMINATE
TODAY....BUT A BRIEF PERIOD OF IFR CONDITIONS ARE POSSIBLE THIS
MORNING IN SNOW SHOWERS.

OUTLOOK...MONDAY THROUGH THURSDAY...MODERATE CONFIDENCE.

MONDAY...MVFR CIGS CONTINUE IN RI/EASTERN MASS IN MARINE EAST FLOW.
VFR IN THE WEST.

TUESDAY...VFR WITH SCATTERED MVFR IN ANY RAIN/SNOW SHOWERS.

WEDNESDAY...CONDITIONS LOWERING TO IFR IN RAIN/HEAVY RAIN. ISOLATED
THUNDERSTORMS POSSIBLE ESPECIALLY WEDNESDAY NIGHT. EAST-SOUTHEAST
SURFACE WINDS MAY GUST TO 35-45 KNOTS. WINDS AT 2000 FEET AGL WILL
REACH 50-60 KNOTS WEDNESDAY AFTERNOON AND EARLY NIGHT CREATING LOW
LEVEL WIND SHEAR CONCERNS.

CHRISTMAS DAY...WEST WIND GUSTING 30-40 KNOTS. CONDITIONS IMPROVING
TO VFR AS THE WIND BRINGS IN COOLER DRIER AIR.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /TODAY AND TONIGHT/...HIGH CONFIDENCE.

HIGH PRESSURE ACROSS QUEBEC WILL RESULT IN NORTHEAST WINDS ACROSS
THE WATERS THAT WILL GUST TO BETWEEN 15 AND 20 KNOTS.  THIS WILL
RESULT IN 2 TO 4 FOOT SEAS.  HOWEVER...NO HEADLINES PLANNED AS
CONDITIONS SHOULD REMAIN BELOW SMALL CRAFT ADVISORY THRESHOLDS.

OUTLOOK...MONDAY THROUGH THURSDAY...MODERATE CONFIDENCE

MONDAY...EAST TO NORTHEAST WINDS GUSTING AROUND 15 KNOTS OR LESS.
SEAS WILL HOLD AROUND 3-4 FEET...MAY INCREASE TO 5FT IN NORTHEAST
FLOW AS GUIDANCE MAY BE UNDERDONE.

TUESDAY... INCREASING EAST WINDS WITH FREQUENT GUSTS 25 TO 30 KNOTS.
SEAS WILL BUILD TO 5-6 FEET ON THE EXPOSED WATERS.  A SMALL CRAFT
ADVISORY MAY BE NEEDED.

WEDNESDAY...RAIN WILL BE HEAVY AT TIMES PRODUCING POOR VISIBILITY.
INCREASING SOUTHEAST WINDS 20-25 SUSTAINED AND 40 KNOT GUSTS.  WINDS
SHOULD SHIFT TO SOUTH WEDNESDAY NIGHT AND SOUTHWEST TOWARD THURSDAY
MORNING. RAIN WILL TAPER OFF WITH THE WIND SHIFT TO SOUTHWEST. SEAS
WILL CONTINUE TO BUILD WITH 7-11 FEET HEIGHTS ON THE EXPOSED WATERS.
A GALE WARNING WILL BE NEEDED...WITH A LOW PROB OF A FEW STORM FORCE
GUSTS ACROSS THE EASTERN OUTER WATERS.

CHRISTMAS DAY... WEST SOUTHWEST WINDS WILL CONTINUE TO GUST 35-40
KNOTS...SO A CONTINUED GALE WARNING MAY BE NEEDED. SEAS OF 7-15 FEET
ARE POSSIBLE ON THE EXPOSED WATERS...AND 5 FEET IS POSSIBLE ON SOME
OF THE NEARSHORE WATERS.

&&

.TIDES/COASTAL FLOODING...
HIGH ASTRONOMICAL TIDES WILL OCCUR TUESDAY THROUGH THURSDAY. BREAKING
IT DOWN...ON TUESDAY HIGH TIDE AT BOSTON WILL BE 11.6 FT. THERE WILL
BE ONSHORE FLOW DURING THIS HIGH TIDE ALLOWING FOR MINOR SPLASHOVER.
IF WIND GUSTS INCREASE THEN COULD POSSIBLE SEE MINOR COASTAL
FLOODING.

ON WEDNESDAY...WINDS WILL SWITCH TO A MORE SOUTHEASTERLY FLOW DURING
THE DAY AND INCREASE QUICKLY FROM APPROACHING SYSTEM AND DECENT
PRESSURE FALLS. WEDNESDAY AFTERNOON HIGH TIDE IN BOSTON IS 11.7 FT
AND WITH ANY STRENGTH ON THE EASTERLY WIND FLOW WILL PUSH THE TIDE
OVER. RIGHT NOW BELIEVE MINOR COASTAL FLOODING IS POSSIBLE ALONG THE
EAST COASTLINE.

WEDNESDAY EVENING...THE WIND GOES IN A MORE SOUTHERLY DIRECTION AND
THE TIDE WILL BE INCREASE ACROSS THE SOUTH COAST. HIGH TIDE IN
PROVIDENCE WILL BE 5.2 FT. 925 MB LLJ STRENGTHENS TO 50-60 KTS WHICH
COULD PUSH A DECENT SURGE UP ALONG THE SOUTH COAST DURING THE TIME
OF HIGH TIDE. THINKING THAT MINOR COASTAL FLOODING COULD OCCUR BUT
CANNOT RULE OUT MODERATE ALONG THE SOUTH COAST...ESP IF LLJ
STRENGTHENS EVEN MORE.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...FRANK/DUNTEN
NEAR TERM...FRANK/DUNTEN/RLG
SHORT TERM...FRANK
LONG TERM...DUNTEN
AVIATION...FRANK/DUNTEN
MARINE...FRANK/DUNTEN
TIDES/COASTAL FLOODING...




000
FXUS61 KBOX 211452
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
952 AM EST SUN DEC 21 2014

.SYNOPSIS...
SCATTERED SNOW/RAIN SHOWERS CONTINUE THROUGH THIS AFTERNOON. WEAK
LOW PRESSURE WILL PASS SOUTH OF NEW ENGLAND BRINGING ANOTHER
PERIOD OF PRECIPITATION MONDAY NIGHT AND TUESDAY. A MUCH STRONGER
STORM PASSING WEST OF NEW ENGLAND WILL BRING HEAVY RAINFALL...
GUSTY WINDS AND COASTAL FLOODING CONCERNS TO THE REGION WEDNESDAY
AND WEDNESDAY NIGHT. DRY BUT VERY WINDY CONDITIONS FOLLOW FOR
CHRISTMAS DAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
10 AM UPDATE...SCATTERED SNOW SHOWERS CONTINUE ACROSS SOUTHERN NEW
ENGLAND THIS MORNING. MOST OF THESE ARE TOO LIGHT EVEN TO SHOW UP
ON RADAR BUT THEY ARE BEING REPORTED IN GROUND TRUTH REPORTS FROM
SOCIAL MEDIA AND THE PUBLIC.

PREVIOUS DISCUSSION...

THE RAIN/SNOW LINE RUNS ROUGHLY FROM NEWPORT...TO TAUNTON AND
JUST NORTH OF MARSHFIELD. OVERALL...DO NOT EXPECT MUCH CHANGE IN
THE RAIN/SNOW LINE THIS MORNING BASED ON THERMAL PROFILES AND
POSITIONING OF THE COASTAL FRONT.

MAIN UNCERTAINTY IS JUST HOW MUCH SNOW OCCURS THIS MORNING WITH THE
SHORTWAVE MOVING ACROSS CT.  GIVEN THE TRACK OF THE SHORTWAVE...BEST
FORCING WILL BE LOCATED SOUTH OF THE MA TURNPIKE AND ESPECIALLY
ACROSS NORTHERN CT/RI.  WE WILL FORECAST 1 TO 2 INCHES OF SNOW
ACROSS THIS REGION...BUT A FEW ISOLATED 3 INCH AMOUNTS CAN NOT BE
RULED OUT. MEANWHILE...AREAS NORTH OF THE MA TURNPIKE WILL BE
REMOVED FROM THE BEST FORCING...BUT STILL SEE SOME SCATTERED
SHOWERS.  ACCUMS IN THIS AREA LIKELY TO BE A DUSTING TO LESS THAN AN
INCH.

ALSO...SOME OF THE PRECIPITATION CURRENTLY ACROSS SOUTHEAST MA IS
BEING ENHANCED FROM THE COASTAL FRONT.  A LOT OF THIS PRECIP WILL
BE IN THE FORM OF RAIN SHOWERS ACROSS PLYMOUTH AND EVEN INTO
PORTIONS OF BRISTOL COUNTY...POINTS SOUTH AND EAST.  HOWEVER...AT
LEAST THE SLIGHTLY HIGHER TERRAIN OF SOUTHEAST MA SHOULD SEE SNOW
SHOWERS.  WILL HAVE TO KEEP A CLOSE EYE ON IF COASTAL FRONT SHIFTS
SLIGHTLY THIS MORNING.  IT COULD MEAN THE DIFFERENCE BETWEEN AN AREA
GETTING MAINLY RAIN SHOWERS OR PERHAPS AN INCH OR SO OF SNOW.
OVERALL...DO NOT EXPECT THE COASTAL FRONT TO MOVE TOO MUCH THIS
MORNING...BUT JUST A FEW MILES CAN MAKE DIFFERENCE FOR A
PARTICULARLY NEIGHBORHOOD.

BULK OF PRECIPITATION WILL BE THIS MORNING WITH THE SHORTWAVE.
HOWEVER...ENOUGH LOW LEVEL MOISTURE/WEAK LIFT WILL REMAIN THIS
AFTERNOON FOR AT LEAST THIS RISK OF SCATTERED PRECIPITATION AND WILL
MAINTAIN SOME POPS.  HIGH TEMPS MAINLY IN THE 30S.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...
TONIGHT...

A RATHER CLOUDY AND RAW NIGHT ACROSS SOUTHERN NEW ENGLAND.  WHILE
THERE IS NOT A SIGNIFICANT SHORTWAVE TO TRIGGER A LOT OF
PRECIPITATION...PLENTY OF LOW LEVEL MOISTURE/WEAK SHALLOW LIFT
REMAINS.  THIS MAY BE ENOUGH TO RESULT IN A FEW RAIN/SNOW SHOWER
FROM TIME TO TIME.  PTYPE...WOULD BE MAINLY SNOW SHOWERS EXCEPT TO
THE SOUTHEAST OF A NEWPORT...TO TAUNTON...TO JUST NORTH OF
MARSHFIELD LINE.  AGAIN...MUCH OF THE NIGHT WILL PROBABLY END UP
DRY...BUT JUST THE RISK FOR A FEW RAIN/SNOW SHOWERS.

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...
HIGHLIGHTS...

* WEAK SHORTWAVE ON MON NIGHT/TUESDAY COULD BRING WINTRY
  MIX/FREEZING RAIN TO THE INTERIOR
* ANOMALOUS SYSTEM ACROSS THE GREAT LAKES WILL BRING HEAVY
  RAIN...GUSTY WINDS AND COASTAL FLOODING CONCERNS AROUND CHRISTMAS
  EVE
* BLUSTERY BUT AIRMASS WILL BE DRYING OUT ON CHRISTMAS DAY

OVERVIEW...

THE MODELS AND ENSEMBLES OFFER A REASONABLY SIMILAR AND PREDICTABLE
LARGER SCALE MID TO UPPER LEVEL PATTERN EVOLUTION FOR MUCH OF THE
UPCOMING WEEK. THIS ACTIVE FLOW REGIME DEVELOPS SEVERAL MID-UPPER
LEVEL TROUGH AND ASSOCIATED/UNSETTLING LEAD SURFACE LOW/FRONTAL
SYSTEMS AND PCPN SWATHS PROGRESS STEADILY ACROSS THE LOWER 48. THE
FIRST AMPLIFIED/DEEP LEAD SYSTEM WORKS ACROSS THE ERN/NERN US INTO
ERN CANADA CHRISTMAS EVE INTO CHRISTMAS ALLOWING FOR A MOIST/WARMED
AIRMASS IN ADVANCE OF FRONTAL APPROACH WITH HEAVIEST LEAD QPF
POTENTIAL OVER NEW ENGLAND. BIGGEST QUESTION IS THE EVOLUTION OF THE
SECONDARY LOW PRESSURE SYSTEM. 00Z GUIDANCE HAS BACKED OFF ON THE
STRENGTH OF THE LOW AND IS HAVING ISSUES ON HOW TO HANDLE ITS
EVOLUTION. THE EC AND GFS HAVE SLOWED DOWN THE SYSTEM SLIGHTLY WITH
THE EC HAVING MORE OF A NEGATIVE TROUGH VS THE GFS. BELIEVE THE
UKMET IS A GOOD COMPROMISE AT IS WAS THE FIRST DETERMINISTIC
GUIDANCE ON TAMPERING DOWN THE FIRST MAIN LOW...WHILE THE CMC IS OUT
TO LUNCH. REGARDLESS THIS IS A VERY ANOMALOUS SYSTEM THAT IS ABOUT 4
STANDARD DEVIATIONS AWAY.

A SECONDARY SYSTEM DEEPENS ACROSS THE FOUR CORNERS ON FRIDAY AND
WITH THE STUBBORN TROUGH OVER THE CENTRAL U.S...IT WILL PUSH A
SYSTEM TOWARDS SOUTHERN NEW ENGLAND BY SUNDAY. THIS SYSTEM MAY
SUPPORT A MODEST SWATH OF OVERRUNNING SNOW OVER SOUTHERN NEW
ENGLAND.

DETAILS...

MONDAY INTO TUESDAY...MODERATE CONFIDENCE.

A WEAK WAVE OF LOW PRESSURE DEVELOPS ALONG THE SOUTHEAST COAST
MONDAY...AND WILL BE ON A DEVELOPING WARM FRONTAL BOUNDARY. THIS LOW
REMAINS WEAK AS THE WARM FRONT MOVES SLOWLY NORTH MONDAY NIGHT INTO
TUESDAY. APPEARS THAT THERE IS DECENT WARM ADVECTION AHEAD OF THIS
WAVE. SEVERAL HI-RES GUIDANCE MODELS SHOW THAT THERE IS THE
POTENTIAL FOR COLD AIR DAMMING ACROSS THE INTERIOR INTO TUESDAY.
BIGGEST QUESTION WILL BE IS THERE ENOUGH MOISTURE FOR PRECIP DURING
THIS TIME FRAME. DUE TO A STRENGTHENING LLJ PROVIDING A GOOD SOURCE OF
LIFT ANTICIPATE PRECIP TO DEVELOP AND OVERSPREAD ACROSS SOUTHERN NEW
ENGLAND. IF THIS PLAYS OUT WITH COLD AIR DAMMING AND WARM AIR
ADVECTION...THEN WE COULD SEE FREEZING RAIN/DRIZZLE ACROSS THE I-91
CORRIDOR LATE MONDAY INTO TUESDAY MORNING. DURING THE DAY ON
TUESDAY...GOOD AMOUNT OF WARM AIR WILL PUSH SURFACE TEMPS ABOVE
FREEZING BY THE LATE MORNING ALLOWING FOR ANY PRECIP TO BE MORE OF
THE LIQUID VARIETY AHEAD OF THE CHRISTMAS EVE STORM. HOWEVER
GUIDANCE IS ALWAYS TOO FAST IN SCOURING TEMPS OUT ESP ACROSS THE CT
VALLEY SO WE WILL NEED TO MONITOR THIS CLOSELY...ESP DUE TO LIGHT
WINDS AND THE HIGH IN EASTERN CANADA. A WINTER WX ADVISORY MAY BE
NEEDED FOR THE LIGHT ICING POTENTIAL.

WE COULD ALSO SEE SOME MINOR COASTAL FLOODING CONCERNS ON TUESDAY. SEE
BELOW FOR MORE DETAILS.

WEDNESDAY INTO THURSDAY...HIGH CONFIDENCE IN SYSTEM LOW CONFIDENCE
ON DETAILS.

ANOMALOUS SYSTEM WILL STRENGTHEN OVER THE GREAT LAKES TUESDAY INTO
WEDNESDAY. A SECONDARY SHORTWAVE WILL ROUND THE DEEP TROUGH AND
DEVELOP A SECONDARY LOW PRESSURE ALONG THE COLD FRONT. THIS
SECONDARY LOW WILL STRENGTHEN AND PASS WEST OF SOUTHERN NEW ENGLAND.
THIS SYSTEM WILL CONTINUE TO DEEPEN AS IT MOVES TOWARDS EASTERN
CANADA SWINGING A COLD FRONT ACROSS THE NORTHEAST.

STRONG SOUTHERLY JET OUT AHEAD OF THE FRONT WITH A GULF MOISTURE
CONNECTION WILL IMPACT SOUTHERN NEW ENGLAND ON CHRISTMAS EVE. THIS
STRONG JET WILL YIELD FOR PCPN IN THE LIQUID VARIETY.  PW ANOMALIES
ARE BETWEEN +4 TO +5 STANDARD DEVIATIONS ABOVE NORMAL WHICH IS QUITE
ANOMALOUS FOR THIS TIME OF YEAR. IN FACT CURRENT PWATS ARE PROGGED
ABOVE 1.6 INCHES WITH MODEL QPF OVER 2 INCHES...AT THE VERY LEAST
COULD SEE URBAN AND POOR DRAINAGE FLOODING. LATEST EC EVEN SHOWS
OVER 2.5 INCHES OF QPF...AND WITH THE TROPICAL CONNECTION AND STRONG
SOUTHERLY FLOW COULD SEE HIGHER AMOUNTS DUE TO TOPOGRAPHY
ENHANCEMENTS. RAINFALL RECORDS MAY FALL IF EVERYTHING FALLS INTO
PLACE.

AHEAD OF THE FRONT...SOUTHERN NEW ENGLAND WILL WARM SECTOR WED INTO
THUR MORNING ALLOWING FOR TEMPERATURES TO BE WELL ABOVE AVERAGE. IN
FACT WE MAY BE CLOSE AT BREAKING RECORD HIGH TEMPS IF TEMPS WARM TO
60F OR ABOVE ON CHRISTMAS EVE. SINCE WE WILL BE IN THE WARM
SECTOR...AND SHOWALTERS CLOSE TO ZERO...ISOLATED THUNDER IS STILL
POSSIBLE.

STRONG LOW LEVEL WINDS WILL ALSO BE A CONCERN ESPECIALLY WEDNESDAY
NIGHT. THE ECMWF SHOWS EAST-SOUTHEAST WINDS 30-40 KNOTS ON WEDNESDAY
INCREASING TO 60-75 KNOTS BY WEDNESDAY NIGHT. STRONG DOWNPOURS MAY
OVERCOME THE LOW LEVEL INVERSION AND BRING STRONG GUSTS OF AT LEAST
30-40 KNOTS ESPECIALLY ALONG THE SOUTH COAST. A WIND ADVISORY MAY BE
NEEDED IN SOME AREAS.

CHRISTMAS DAY...MODERATE CONFIDENCE.

AS THE COLD FRONT PASSES THROUGH EARLY CHRISTMAS DAY...THE WEST
WINDS WILL HELP DRY THE AIRMASS ALLOWING FOR PARTLY SUNNY SKIES.
STRONG CAA ON THURSDAY WILL ALLOW DESCENT MIXING. WINDS IN THE SFC-
850 MB LAYER WILL BE 30-40 KNOTS AND POSSIBLY A LITTLE
HIGHER...WHICH WOULD REQUIRE A WIND ADVISORY FOR MUCH OF THE AREA.

FRIDAY-SUNDAY...LOWER CONFIDENCE

WEAK HIGH PRESSURE BUILDS OVER THE AREA FRIDAY INTO SATURDAY. THE
NEXT SHORTWAVE APPROACHES LATE SATURDAY INTO SUNDAY AND SHOULD BRING
INCREASING CLOUDS FROM WEST TO EAST ALONG WITH A CHANCE OF RAIN OR
SNOW SHOWERS MAINLY IN THE AFTERNOON AND AT NIGHT.

&&

.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /TODAY AND TONIGHT/...

TODAY AND TONIGHT...MODERATE CONFIDENCE.  MAINLY MVFR CONDITIONS
SOUTH OF THE MA TURNPIKE WITH BORDERLINE VFR TO MARGINAL MVFR CIGS
NORTH OF THE PIKE THROUGH TONIGHT.  AN AREA OF SNOW SHOWERS WILL
EXPAND MAINLY ACROSS AREAS SOUTH OF THE PIKE THIS MORNING...BUT A
FEW SNOW SHOWERS WILL STILL AFFECT NORTHERN MA.  VSBYS/CIGS MAY
BRIEFLY DROP TO IFR LEVELS IN NORTHERN CT/RI/SE MA.  PTYPE WILL BE
RAIN SHOWERS ACROSS MOST OF PLYMOUTH COUNTY AND ONTO THE
CAPE/ISLANDS WITH SNOW SHOWERS NORTH AND WEST.  BULK OF PRECIP THIS
MORNING...BUT A FEW LINGERING RAIN/SNOW SHOWERS STILL POSSIBLE THIS
AFTERNOON AND EVENING.

KBOS TERMINAL...MODERATE CONFIDENCE.  A FEW SNOW SHOWERS POSSIBLE
THIS MORNING BUT BULK OF ACTIVITY SHOULD BE SOUTH OF THE TERMINAL.

KBDL TERMINAL...MODERATE CONFIDENCE.  PERIOD OF SNOW SHOWERS THIS
MORNING MAY DROP AN INCH OR TWO OF SNOW.  MVFR CONDITIONS DOMINATE
TODAY....BUT A BRIEF PERIOD OF IFR CONDITIONS ARE POSSIBLE THIS
MORNING IN SNOW SHOWERS.

OUTLOOK...MONDAY THROUGH THURSDAY...MODERATE CONFIDENCE.

MONDAY...MVFR CIGS CONTINUE IN RI/EASTERN MASS IN MARINE EAST FLOW.
VFR IN THE WEST.

TUESDAY...VFR WITH SCATTERED MVFR IN ANY RAIN/SNOW SHOWERS.

WEDNESDAY...CONDITIONS LOWERING TO IFR IN RAIN/HEAVY RAIN. ISOLATED
THUNDERSTORMS POSSIBLE ESPECIALLY WEDNESDAY NIGHT. EAST-SOUTHEAST
SURFACE WINDS MAY GUST TO 35-45 KNOTS. WINDS AT 2000 FEET AGL WILL
REACH 50-60 KNOTS WEDNESDAY AFTERNOON AND EARLY NIGHT CREATING LOW
LEVEL WIND SHEAR CONCERNS.

CHRISTMAS DAY...WEST WIND GUSTING 30-40 KNOTS. CONDITIONS IMPROVING
TO VFR AS THE WIND BRINGS IN COOLER DRIER AIR.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /TODAY AND TONIGHT/...HIGH CONFIDENCE.

HIGH PRESSURE ACROSS QUEBEC WILL RESULT IN NORTHEAST WINDS ACROSS
THE WATERS THAT WILL GUST TO BETWEEN 15 AND 20 KNOTS.  THIS WILL
RESULT IN 2 TO 4 FOOT SEAS.  HOWEVER...NO HEADLINES PLANNED AS
CONDITIONS SHOULD REMAIN BELOW SMALL CRAFT ADVISORY THRESHOLDS.

OUTLOOK...MONDAY THROUGH THURSDAY...MODERATE CONFIDENCE

MONDAY...EAST TO NORTHEAST WINDS GUSTING AROUND 15 KNOTS OR LESS.
SEAS WILL HOLD AROUND 3-4 FEET...MAY INCREASE TO 5FT IN NORTHEAST
FLOW AS GUIDANCE MAY BE UNDERDONE.

TUESDAY... INCREASING EAST WINDS WITH FREQUENT GUSTS 25 TO 30 KNOTS.
SEAS WILL BUILD TO 5-6 FEET ON THE EXPOSED WATERS.  A SMALL CRAFT
ADVISORY MAY BE NEEDED.

WEDNESDAY...RAIN WILL BE HEAVY AT TIMES PRODUCING POOR VISIBILITY.
INCREASING SOUTHEAST WINDS 20-25 SUSTAINED AND 40 KNOT GUSTS.  WINDS
SHOULD SHIFT TO SOUTH WEDNESDAY NIGHT AND SOUTHWEST TOWARD THURSDAY
MORNING. RAIN WILL TAPER OFF WITH THE WIND SHIFT TO SOUTHWEST. SEAS
WILL CONTINUE TO BUILD WITH 7-11 FEET HEIGHTS ON THE EXPOSED WATERS.
A GALE WARNING WILL BE NEEDED...WITH A LOW PROB OF A FEW STORM FORCE
GUSTS ACROSS THE EASTERN OUTER WATERS.

CHRISTMAS DAY... WEST SOUTHWEST WINDS WILL CONTINUE TO GUST 35-40
KNOTS...SO A CONTINUED GALE WARNING MAY BE NEEDED. SEAS OF 7-15 FEET
ARE POSSIBLE ON THE EXPOSED WATERS...AND 5 FEET IS POSSIBLE ON SOME
OF THE NEARSHORE WATERS.

&&

.TIDES/COASTAL FLOODING...
HIGH ASTRONOMICAL TIDES WILL OCCUR TUESDAY THROUGH THURSDAY. BREAKING
IT DOWN...ON TUESDAY HIGH TIDE AT BOSTON WILL BE 11.6 FT. THERE WILL
BE ONSHORE FLOW DURING THIS HIGH TIDE ALLOWING FOR MINOR SPLASHOVER.
IF WIND GUSTS INCREASE THEN COULD POSSIBLE SEE MINOR COASTAL
FLOODING.

ON WEDNESDAY...WINDS WILL SWITCH TO A MORE SOUTHEASTERLY FLOW DURING
THE DAY AND INCREASE QUICKLY FROM APPROACHING SYSTEM AND DECENT
PRESSURE FALLS. WEDNESDAY AFTERNOON HIGH TIDE IN BOSTON IS 11.7 FT
AND WITH ANY STRENGTH ON THE EASTERLY WIND FLOW WILL PUSH THE TIDE
OVER. RIGHT NOW BELIEVE MINOR COASTAL FLOODING IS POSSIBLE ALONG THE
EAST COASTLINE.

WEDNESDAY EVENING...THE WIND GOES IN A MORE SOUTHERLY DIRECTION AND
THE TIDE WILL BE INCREASE ACROSS THE SOUTH COAST. HIGH TIDE IN
PROVIDENCE WILL BE 5.2 FT. 925 MB LLJ STRENGTHENS TO 50-60 KTS WHICH
COULD PUSH A DECENT SURGE UP ALONG THE SOUTH COAST DURING THE TIME
OF HIGH TIDE. THINKING THAT MINOR COASTAL FLOODING COULD OCCUR BUT
CANNOT RULE OUT MODERATE ALONG THE SOUTH COAST...ESP IF LLJ
STRENGTHENS EVEN MORE.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...FRANK/DUNTEN
NEAR TERM...FRANK/DUNTEN/RLG
SHORT TERM...FRANK
LONG TERM...DUNTEN
AVIATION...FRANK/DUNTEN
MARINE...FRANK/DUNTEN
TIDES/COASTAL FLOODING...




000
FXUS61 KBOX 211452
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
952 AM EST SUN DEC 21 2014

.SYNOPSIS...
SCATTERED SNOW/RAIN SHOWERS CONTINUE THROUGH THIS AFTERNOON. WEAK
LOW PRESSURE WILL PASS SOUTH OF NEW ENGLAND BRINGING ANOTHER
PERIOD OF PRECIPITATION MONDAY NIGHT AND TUESDAY. A MUCH STRONGER
STORM PASSING WEST OF NEW ENGLAND WILL BRING HEAVY RAINFALL...
GUSTY WINDS AND COASTAL FLOODING CONCERNS TO THE REGION WEDNESDAY
AND WEDNESDAY NIGHT. DRY BUT VERY WINDY CONDITIONS FOLLOW FOR
CHRISTMAS DAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
10 AM UPDATE...SCATTERED SNOW SHOWERS CONTINUE ACROSS SOUTHERN NEW
ENGLAND THIS MORNING. MOST OF THESE ARE TOO LIGHT EVEN TO SHOW UP
ON RADAR BUT THEY ARE BEING REPORTED IN GROUND TRUTH REPORTS FROM
SOCIAL MEDIA AND THE PUBLIC.

PREVIOUS DISCUSSION...

THE RAIN/SNOW LINE RUNS ROUGHLY FROM NEWPORT...TO TAUNTON AND
JUST NORTH OF MARSHFIELD. OVERALL...DO NOT EXPECT MUCH CHANGE IN
THE RAIN/SNOW LINE THIS MORNING BASED ON THERMAL PROFILES AND
POSITIONING OF THE COASTAL FRONT.

MAIN UNCERTAINTY IS JUST HOW MUCH SNOW OCCURS THIS MORNING WITH THE
SHORTWAVE MOVING ACROSS CT.  GIVEN THE TRACK OF THE SHORTWAVE...BEST
FORCING WILL BE LOCATED SOUTH OF THE MA TURNPIKE AND ESPECIALLY
ACROSS NORTHERN CT/RI.  WE WILL FORECAST 1 TO 2 INCHES OF SNOW
ACROSS THIS REGION...BUT A FEW ISOLATED 3 INCH AMOUNTS CAN NOT BE
RULED OUT. MEANWHILE...AREAS NORTH OF THE MA TURNPIKE WILL BE
REMOVED FROM THE BEST FORCING...BUT STILL SEE SOME SCATTERED
SHOWERS.  ACCUMS IN THIS AREA LIKELY TO BE A DUSTING TO LESS THAN AN
INCH.

ALSO...SOME OF THE PRECIPITATION CURRENTLY ACROSS SOUTHEAST MA IS
BEING ENHANCED FROM THE COASTAL FRONT.  A LOT OF THIS PRECIP WILL
BE IN THE FORM OF RAIN SHOWERS ACROSS PLYMOUTH AND EVEN INTO
PORTIONS OF BRISTOL COUNTY...POINTS SOUTH AND EAST.  HOWEVER...AT
LEAST THE SLIGHTLY HIGHER TERRAIN OF SOUTHEAST MA SHOULD SEE SNOW
SHOWERS.  WILL HAVE TO KEEP A CLOSE EYE ON IF COASTAL FRONT SHIFTS
SLIGHTLY THIS MORNING.  IT COULD MEAN THE DIFFERENCE BETWEEN AN AREA
GETTING MAINLY RAIN SHOWERS OR PERHAPS AN INCH OR SO OF SNOW.
OVERALL...DO NOT EXPECT THE COASTAL FRONT TO MOVE TOO MUCH THIS
MORNING...BUT JUST A FEW MILES CAN MAKE DIFFERENCE FOR A
PARTICULARLY NEIGHBORHOOD.

BULK OF PRECIPITATION WILL BE THIS MORNING WITH THE SHORTWAVE.
HOWEVER...ENOUGH LOW LEVEL MOISTURE/WEAK LIFT WILL REMAIN THIS
AFTERNOON FOR AT LEAST THIS RISK OF SCATTERED PRECIPITATION AND WILL
MAINTAIN SOME POPS.  HIGH TEMPS MAINLY IN THE 30S.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...
TONIGHT...

A RATHER CLOUDY AND RAW NIGHT ACROSS SOUTHERN NEW ENGLAND.  WHILE
THERE IS NOT A SIGNIFICANT SHORTWAVE TO TRIGGER A LOT OF
PRECIPITATION...PLENTY OF LOW LEVEL MOISTURE/WEAK SHALLOW LIFT
REMAINS.  THIS MAY BE ENOUGH TO RESULT IN A FEW RAIN/SNOW SHOWER
FROM TIME TO TIME.  PTYPE...WOULD BE MAINLY SNOW SHOWERS EXCEPT TO
THE SOUTHEAST OF A NEWPORT...TO TAUNTON...TO JUST NORTH OF
MARSHFIELD LINE.  AGAIN...MUCH OF THE NIGHT WILL PROBABLY END UP
DRY...BUT JUST THE RISK FOR A FEW RAIN/SNOW SHOWERS.

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...
HIGHLIGHTS...

* WEAK SHORTWAVE ON MON NIGHT/TUESDAY COULD BRING WINTRY
  MIX/FREEZING RAIN TO THE INTERIOR
* ANOMALOUS SYSTEM ACROSS THE GREAT LAKES WILL BRING HEAVY
  RAIN...GUSTY WINDS AND COASTAL FLOODING CONCERNS AROUND CHRISTMAS
  EVE
* BLUSTERY BUT AIRMASS WILL BE DRYING OUT ON CHRISTMAS DAY

OVERVIEW...

THE MODELS AND ENSEMBLES OFFER A REASONABLY SIMILAR AND PREDICTABLE
LARGER SCALE MID TO UPPER LEVEL PATTERN EVOLUTION FOR MUCH OF THE
UPCOMING WEEK. THIS ACTIVE FLOW REGIME DEVELOPS SEVERAL MID-UPPER
LEVEL TROUGH AND ASSOCIATED/UNSETTLING LEAD SURFACE LOW/FRONTAL
SYSTEMS AND PCPN SWATHS PROGRESS STEADILY ACROSS THE LOWER 48. THE
FIRST AMPLIFIED/DEEP LEAD SYSTEM WORKS ACROSS THE ERN/NERN US INTO
ERN CANADA CHRISTMAS EVE INTO CHRISTMAS ALLOWING FOR A MOIST/WARMED
AIRMASS IN ADVANCE OF FRONTAL APPROACH WITH HEAVIEST LEAD QPF
POTENTIAL OVER NEW ENGLAND. BIGGEST QUESTION IS THE EVOLUTION OF THE
SECONDARY LOW PRESSURE SYSTEM. 00Z GUIDANCE HAS BACKED OFF ON THE
STRENGTH OF THE LOW AND IS HAVING ISSUES ON HOW TO HANDLE ITS
EVOLUTION. THE EC AND GFS HAVE SLOWED DOWN THE SYSTEM SLIGHTLY WITH
THE EC HAVING MORE OF A NEGATIVE TROUGH VS THE GFS. BELIEVE THE
UKMET IS A GOOD COMPROMISE AT IS WAS THE FIRST DETERMINISTIC
GUIDANCE ON TAMPERING DOWN THE FIRST MAIN LOW...WHILE THE CMC IS OUT
TO LUNCH. REGARDLESS THIS IS A VERY ANOMALOUS SYSTEM THAT IS ABOUT 4
STANDARD DEVIATIONS AWAY.

A SECONDARY SYSTEM DEEPENS ACROSS THE FOUR CORNERS ON FRIDAY AND
WITH THE STUBBORN TROUGH OVER THE CENTRAL U.S...IT WILL PUSH A
SYSTEM TOWARDS SOUTHERN NEW ENGLAND BY SUNDAY. THIS SYSTEM MAY
SUPPORT A MODEST SWATH OF OVERRUNNING SNOW OVER SOUTHERN NEW
ENGLAND.

DETAILS...

MONDAY INTO TUESDAY...MODERATE CONFIDENCE.

A WEAK WAVE OF LOW PRESSURE DEVELOPS ALONG THE SOUTHEAST COAST
MONDAY...AND WILL BE ON A DEVELOPING WARM FRONTAL BOUNDARY. THIS LOW
REMAINS WEAK AS THE WARM FRONT MOVES SLOWLY NORTH MONDAY NIGHT INTO
TUESDAY. APPEARS THAT THERE IS DECENT WARM ADVECTION AHEAD OF THIS
WAVE. SEVERAL HI-RES GUIDANCE MODELS SHOW THAT THERE IS THE
POTENTIAL FOR COLD AIR DAMMING ACROSS THE INTERIOR INTO TUESDAY.
BIGGEST QUESTION WILL BE IS THERE ENOUGH MOISTURE FOR PRECIP DURING
THIS TIME FRAME. DUE TO A STRENGTHENING LLJ PROVIDING A GOOD SOURCE OF
LIFT ANTICIPATE PRECIP TO DEVELOP AND OVERSPREAD ACROSS SOUTHERN NEW
ENGLAND. IF THIS PLAYS OUT WITH COLD AIR DAMMING AND WARM AIR
ADVECTION...THEN WE COULD SEE FREEZING RAIN/DRIZZLE ACROSS THE I-91
CORRIDOR LATE MONDAY INTO TUESDAY MORNING. DURING THE DAY ON
TUESDAY...GOOD AMOUNT OF WARM AIR WILL PUSH SURFACE TEMPS ABOVE
FREEZING BY THE LATE MORNING ALLOWING FOR ANY PRECIP TO BE MORE OF
THE LIQUID VARIETY AHEAD OF THE CHRISTMAS EVE STORM. HOWEVER
GUIDANCE IS ALWAYS TOO FAST IN SCOURING TEMPS OUT ESP ACROSS THE CT
VALLEY SO WE WILL NEED TO MONITOR THIS CLOSELY...ESP DUE TO LIGHT
WINDS AND THE HIGH IN EASTERN CANADA. A WINTER WX ADVISORY MAY BE
NEEDED FOR THE LIGHT ICING POTENTIAL.

WE COULD ALSO SEE SOME MINOR COASTAL FLOODING CONCERNS ON TUESDAY. SEE
BELOW FOR MORE DETAILS.

WEDNESDAY INTO THURSDAY...HIGH CONFIDENCE IN SYSTEM LOW CONFIDENCE
ON DETAILS.

ANOMALOUS SYSTEM WILL STRENGTHEN OVER THE GREAT LAKES TUESDAY INTO
WEDNESDAY. A SECONDARY SHORTWAVE WILL ROUND THE DEEP TROUGH AND
DEVELOP A SECONDARY LOW PRESSURE ALONG THE COLD FRONT. THIS
SECONDARY LOW WILL STRENGTHEN AND PASS WEST OF SOUTHERN NEW ENGLAND.
THIS SYSTEM WILL CONTINUE TO DEEPEN AS IT MOVES TOWARDS EASTERN
CANADA SWINGING A COLD FRONT ACROSS THE NORTHEAST.

STRONG SOUTHERLY JET OUT AHEAD OF THE FRONT WITH A GULF MOISTURE
CONNECTION WILL IMPACT SOUTHERN NEW ENGLAND ON CHRISTMAS EVE. THIS
STRONG JET WILL YIELD FOR PCPN IN THE LIQUID VARIETY.  PW ANOMALIES
ARE BETWEEN +4 TO +5 STANDARD DEVIATIONS ABOVE NORMAL WHICH IS QUITE
ANOMALOUS FOR THIS TIME OF YEAR. IN FACT CURRENT PWATS ARE PROGGED
ABOVE 1.6 INCHES WITH MODEL QPF OVER 2 INCHES...AT THE VERY LEAST
COULD SEE URBAN AND POOR DRAINAGE FLOODING. LATEST EC EVEN SHOWS
OVER 2.5 INCHES OF QPF...AND WITH THE TROPICAL CONNECTION AND STRONG
SOUTHERLY FLOW COULD SEE HIGHER AMOUNTS DUE TO TOPOGRAPHY
ENHANCEMENTS. RAINFALL RECORDS MAY FALL IF EVERYTHING FALLS INTO
PLACE.

AHEAD OF THE FRONT...SOUTHERN NEW ENGLAND WILL WARM SECTOR WED INTO
THUR MORNING ALLOWING FOR TEMPERATURES TO BE WELL ABOVE AVERAGE. IN
FACT WE MAY BE CLOSE AT BREAKING RECORD HIGH TEMPS IF TEMPS WARM TO
60F OR ABOVE ON CHRISTMAS EVE. SINCE WE WILL BE IN THE WARM
SECTOR...AND SHOWALTERS CLOSE TO ZERO...ISOLATED THUNDER IS STILL
POSSIBLE.

STRONG LOW LEVEL WINDS WILL ALSO BE A CONCERN ESPECIALLY WEDNESDAY
NIGHT. THE ECMWF SHOWS EAST-SOUTHEAST WINDS 30-40 KNOTS ON WEDNESDAY
INCREASING TO 60-75 KNOTS BY WEDNESDAY NIGHT. STRONG DOWNPOURS MAY
OVERCOME THE LOW LEVEL INVERSION AND BRING STRONG GUSTS OF AT LEAST
30-40 KNOTS ESPECIALLY ALONG THE SOUTH COAST. A WIND ADVISORY MAY BE
NEEDED IN SOME AREAS.

CHRISTMAS DAY...MODERATE CONFIDENCE.

AS THE COLD FRONT PASSES THROUGH EARLY CHRISTMAS DAY...THE WEST
WINDS WILL HELP DRY THE AIRMASS ALLOWING FOR PARTLY SUNNY SKIES.
STRONG CAA ON THURSDAY WILL ALLOW DESCENT MIXING. WINDS IN THE SFC-
850 MB LAYER WILL BE 30-40 KNOTS AND POSSIBLY A LITTLE
HIGHER...WHICH WOULD REQUIRE A WIND ADVISORY FOR MUCH OF THE AREA.

FRIDAY-SUNDAY...LOWER CONFIDENCE

WEAK HIGH PRESSURE BUILDS OVER THE AREA FRIDAY INTO SATURDAY. THE
NEXT SHORTWAVE APPROACHES LATE SATURDAY INTO SUNDAY AND SHOULD BRING
INCREASING CLOUDS FROM WEST TO EAST ALONG WITH A CHANCE OF RAIN OR
SNOW SHOWERS MAINLY IN THE AFTERNOON AND AT NIGHT.

&&

.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /TODAY AND TONIGHT/...

TODAY AND TONIGHT...MODERATE CONFIDENCE.  MAINLY MVFR CONDITIONS
SOUTH OF THE MA TURNPIKE WITH BORDERLINE VFR TO MARGINAL MVFR CIGS
NORTH OF THE PIKE THROUGH TONIGHT.  AN AREA OF SNOW SHOWERS WILL
EXPAND MAINLY ACROSS AREAS SOUTH OF THE PIKE THIS MORNING...BUT A
FEW SNOW SHOWERS WILL STILL AFFECT NORTHERN MA.  VSBYS/CIGS MAY
BRIEFLY DROP TO IFR LEVELS IN NORTHERN CT/RI/SE MA.  PTYPE WILL BE
RAIN SHOWERS ACROSS MOST OF PLYMOUTH COUNTY AND ONTO THE
CAPE/ISLANDS WITH SNOW SHOWERS NORTH AND WEST.  BULK OF PRECIP THIS
MORNING...BUT A FEW LINGERING RAIN/SNOW SHOWERS STILL POSSIBLE THIS
AFTERNOON AND EVENING.

KBOS TERMINAL...MODERATE CONFIDENCE.  A FEW SNOW SHOWERS POSSIBLE
THIS MORNING BUT BULK OF ACTIVITY SHOULD BE SOUTH OF THE TERMINAL.

KBDL TERMINAL...MODERATE CONFIDENCE.  PERIOD OF SNOW SHOWERS THIS
MORNING MAY DROP AN INCH OR TWO OF SNOW.  MVFR CONDITIONS DOMINATE
TODAY....BUT A BRIEF PERIOD OF IFR CONDITIONS ARE POSSIBLE THIS
MORNING IN SNOW SHOWERS.

OUTLOOK...MONDAY THROUGH THURSDAY...MODERATE CONFIDENCE.

MONDAY...MVFR CIGS CONTINUE IN RI/EASTERN MASS IN MARINE EAST FLOW.
VFR IN THE WEST.

TUESDAY...VFR WITH SCATTERED MVFR IN ANY RAIN/SNOW SHOWERS.

WEDNESDAY...CONDITIONS LOWERING TO IFR IN RAIN/HEAVY RAIN. ISOLATED
THUNDERSTORMS POSSIBLE ESPECIALLY WEDNESDAY NIGHT. EAST-SOUTHEAST
SURFACE WINDS MAY GUST TO 35-45 KNOTS. WINDS AT 2000 FEET AGL WILL
REACH 50-60 KNOTS WEDNESDAY AFTERNOON AND EARLY NIGHT CREATING LOW
LEVEL WIND SHEAR CONCERNS.

CHRISTMAS DAY...WEST WIND GUSTING 30-40 KNOTS. CONDITIONS IMPROVING
TO VFR AS THE WIND BRINGS IN COOLER DRIER AIR.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /TODAY AND TONIGHT/...HIGH CONFIDENCE.

HIGH PRESSURE ACROSS QUEBEC WILL RESULT IN NORTHEAST WINDS ACROSS
THE WATERS THAT WILL GUST TO BETWEEN 15 AND 20 KNOTS.  THIS WILL
RESULT IN 2 TO 4 FOOT SEAS.  HOWEVER...NO HEADLINES PLANNED AS
CONDITIONS SHOULD REMAIN BELOW SMALL CRAFT ADVISORY THRESHOLDS.

OUTLOOK...MONDAY THROUGH THURSDAY...MODERATE CONFIDENCE

MONDAY...EAST TO NORTHEAST WINDS GUSTING AROUND 15 KNOTS OR LESS.
SEAS WILL HOLD AROUND 3-4 FEET...MAY INCREASE TO 5FT IN NORTHEAST
FLOW AS GUIDANCE MAY BE UNDERDONE.

TUESDAY... INCREASING EAST WINDS WITH FREQUENT GUSTS 25 TO 30 KNOTS.
SEAS WILL BUILD TO 5-6 FEET ON THE EXPOSED WATERS.  A SMALL CRAFT
ADVISORY MAY BE NEEDED.

WEDNESDAY...RAIN WILL BE HEAVY AT TIMES PRODUCING POOR VISIBILITY.
INCREASING SOUTHEAST WINDS 20-25 SUSTAINED AND 40 KNOT GUSTS.  WINDS
SHOULD SHIFT TO SOUTH WEDNESDAY NIGHT AND SOUTHWEST TOWARD THURSDAY
MORNING. RAIN WILL TAPER OFF WITH THE WIND SHIFT TO SOUTHWEST. SEAS
WILL CONTINUE TO BUILD WITH 7-11 FEET HEIGHTS ON THE EXPOSED WATERS.
A GALE WARNING WILL BE NEEDED...WITH A LOW PROB OF A FEW STORM FORCE
GUSTS ACROSS THE EASTERN OUTER WATERS.

CHRISTMAS DAY... WEST SOUTHWEST WINDS WILL CONTINUE TO GUST 35-40
KNOTS...SO A CONTINUED GALE WARNING MAY BE NEEDED. SEAS OF 7-15 FEET
ARE POSSIBLE ON THE EXPOSED WATERS...AND 5 FEET IS POSSIBLE ON SOME
OF THE NEARSHORE WATERS.

&&

.TIDES/COASTAL FLOODING...
HIGH ASTRONOMICAL TIDES WILL OCCUR TUESDAY THROUGH THURSDAY. BREAKING
IT DOWN...ON TUESDAY HIGH TIDE AT BOSTON WILL BE 11.6 FT. THERE WILL
BE ONSHORE FLOW DURING THIS HIGH TIDE ALLOWING FOR MINOR SPLASHOVER.
IF WIND GUSTS INCREASE THEN COULD POSSIBLE SEE MINOR COASTAL
FLOODING.

ON WEDNESDAY...WINDS WILL SWITCH TO A MORE SOUTHEASTERLY FLOW DURING
THE DAY AND INCREASE QUICKLY FROM APPROACHING SYSTEM AND DECENT
PRESSURE FALLS. WEDNESDAY AFTERNOON HIGH TIDE IN BOSTON IS 11.7 FT
AND WITH ANY STRENGTH ON THE EASTERLY WIND FLOW WILL PUSH THE TIDE
OVER. RIGHT NOW BELIEVE MINOR COASTAL FLOODING IS POSSIBLE ALONG THE
EAST COASTLINE.

WEDNESDAY EVENING...THE WIND GOES IN A MORE SOUTHERLY DIRECTION AND
THE TIDE WILL BE INCREASE ACROSS THE SOUTH COAST. HIGH TIDE IN
PROVIDENCE WILL BE 5.2 FT. 925 MB LLJ STRENGTHENS TO 50-60 KTS WHICH
COULD PUSH A DECENT SURGE UP ALONG THE SOUTH COAST DURING THE TIME
OF HIGH TIDE. THINKING THAT MINOR COASTAL FLOODING COULD OCCUR BUT
CANNOT RULE OUT MODERATE ALONG THE SOUTH COAST...ESP IF LLJ
STRENGTHENS EVEN MORE.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...FRANK/DUNTEN
NEAR TERM...FRANK/DUNTEN/RLG
SHORT TERM...FRANK
LONG TERM...DUNTEN
AVIATION...FRANK/DUNTEN
MARINE...FRANK/DUNTEN
TIDES/COASTAL FLOODING...




000
FXUS61 KBOX 211452
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
952 AM EST SUN DEC 21 2014

.SYNOPSIS...
SCATTERED SNOW/RAIN SHOWERS CONTINUE THROUGH THIS AFTERNOON. WEAK
LOW PRESSURE WILL PASS SOUTH OF NEW ENGLAND BRINGING ANOTHER
PERIOD OF PRECIPITATION MONDAY NIGHT AND TUESDAY. A MUCH STRONGER
STORM PASSING WEST OF NEW ENGLAND WILL BRING HEAVY RAINFALL...
GUSTY WINDS AND COASTAL FLOODING CONCERNS TO THE REGION WEDNESDAY
AND WEDNESDAY NIGHT. DRY BUT VERY WINDY CONDITIONS FOLLOW FOR
CHRISTMAS DAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
10 AM UPDATE...SCATTERED SNOW SHOWERS CONTINUE ACROSS SOUTHERN NEW
ENGLAND THIS MORNING. MOST OF THESE ARE TOO LIGHT EVEN TO SHOW UP
ON RADAR BUT THEY ARE BEING REPORTED IN GROUND TRUTH REPORTS FROM
SOCIAL MEDIA AND THE PUBLIC.

PREVIOUS DISCUSSION...

THE RAIN/SNOW LINE RUNS ROUGHLY FROM NEWPORT...TO TAUNTON AND
JUST NORTH OF MARSHFIELD. OVERALL...DO NOT EXPECT MUCH CHANGE IN
THE RAIN/SNOW LINE THIS MORNING BASED ON THERMAL PROFILES AND
POSITIONING OF THE COASTAL FRONT.

MAIN UNCERTAINTY IS JUST HOW MUCH SNOW OCCURS THIS MORNING WITH THE
SHORTWAVE MOVING ACROSS CT.  GIVEN THE TRACK OF THE SHORTWAVE...BEST
FORCING WILL BE LOCATED SOUTH OF THE MA TURNPIKE AND ESPECIALLY
ACROSS NORTHERN CT/RI.  WE WILL FORECAST 1 TO 2 INCHES OF SNOW
ACROSS THIS REGION...BUT A FEW ISOLATED 3 INCH AMOUNTS CAN NOT BE
RULED OUT. MEANWHILE...AREAS NORTH OF THE MA TURNPIKE WILL BE
REMOVED FROM THE BEST FORCING...BUT STILL SEE SOME SCATTERED
SHOWERS.  ACCUMS IN THIS AREA LIKELY TO BE A DUSTING TO LESS THAN AN
INCH.

ALSO...SOME OF THE PRECIPITATION CURRENTLY ACROSS SOUTHEAST MA IS
BEING ENHANCED FROM THE COASTAL FRONT.  A LOT OF THIS PRECIP WILL
BE IN THE FORM OF RAIN SHOWERS ACROSS PLYMOUTH AND EVEN INTO
PORTIONS OF BRISTOL COUNTY...POINTS SOUTH AND EAST.  HOWEVER...AT
LEAST THE SLIGHTLY HIGHER TERRAIN OF SOUTHEAST MA SHOULD SEE SNOW
SHOWERS.  WILL HAVE TO KEEP A CLOSE EYE ON IF COASTAL FRONT SHIFTS
SLIGHTLY THIS MORNING.  IT COULD MEAN THE DIFFERENCE BETWEEN AN AREA
GETTING MAINLY RAIN SHOWERS OR PERHAPS AN INCH OR SO OF SNOW.
OVERALL...DO NOT EXPECT THE COASTAL FRONT TO MOVE TOO MUCH THIS
MORNING...BUT JUST A FEW MILES CAN MAKE DIFFERENCE FOR A
PARTICULARLY NEIGHBORHOOD.

BULK OF PRECIPITATION WILL BE THIS MORNING WITH THE SHORTWAVE.
HOWEVER...ENOUGH LOW LEVEL MOISTURE/WEAK LIFT WILL REMAIN THIS
AFTERNOON FOR AT LEAST THIS RISK OF SCATTERED PRECIPITATION AND WILL
MAINTAIN SOME POPS.  HIGH TEMPS MAINLY IN THE 30S.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...
TONIGHT...

A RATHER CLOUDY AND RAW NIGHT ACROSS SOUTHERN NEW ENGLAND.  WHILE
THERE IS NOT A SIGNIFICANT SHORTWAVE TO TRIGGER A LOT OF
PRECIPITATION...PLENTY OF LOW LEVEL MOISTURE/WEAK SHALLOW LIFT
REMAINS.  THIS MAY BE ENOUGH TO RESULT IN A FEW RAIN/SNOW SHOWER
FROM TIME TO TIME.  PTYPE...WOULD BE MAINLY SNOW SHOWERS EXCEPT TO
THE SOUTHEAST OF A NEWPORT...TO TAUNTON...TO JUST NORTH OF
MARSHFIELD LINE.  AGAIN...MUCH OF THE NIGHT WILL PROBABLY END UP
DRY...BUT JUST THE RISK FOR A FEW RAIN/SNOW SHOWERS.

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...
HIGHLIGHTS...

* WEAK SHORTWAVE ON MON NIGHT/TUESDAY COULD BRING WINTRY
  MIX/FREEZING RAIN TO THE INTERIOR
* ANOMALOUS SYSTEM ACROSS THE GREAT LAKES WILL BRING HEAVY
  RAIN...GUSTY WINDS AND COASTAL FLOODING CONCERNS AROUND CHRISTMAS
  EVE
* BLUSTERY BUT AIRMASS WILL BE DRYING OUT ON CHRISTMAS DAY

OVERVIEW...

THE MODELS AND ENSEMBLES OFFER A REASONABLY SIMILAR AND PREDICTABLE
LARGER SCALE MID TO UPPER LEVEL PATTERN EVOLUTION FOR MUCH OF THE
UPCOMING WEEK. THIS ACTIVE FLOW REGIME DEVELOPS SEVERAL MID-UPPER
LEVEL TROUGH AND ASSOCIATED/UNSETTLING LEAD SURFACE LOW/FRONTAL
SYSTEMS AND PCPN SWATHS PROGRESS STEADILY ACROSS THE LOWER 48. THE
FIRST AMPLIFIED/DEEP LEAD SYSTEM WORKS ACROSS THE ERN/NERN US INTO
ERN CANADA CHRISTMAS EVE INTO CHRISTMAS ALLOWING FOR A MOIST/WARMED
AIRMASS IN ADVANCE OF FRONTAL APPROACH WITH HEAVIEST LEAD QPF
POTENTIAL OVER NEW ENGLAND. BIGGEST QUESTION IS THE EVOLUTION OF THE
SECONDARY LOW PRESSURE SYSTEM. 00Z GUIDANCE HAS BACKED OFF ON THE
STRENGTH OF THE LOW AND IS HAVING ISSUES ON HOW TO HANDLE ITS
EVOLUTION. THE EC AND GFS HAVE SLOWED DOWN THE SYSTEM SLIGHTLY WITH
THE EC HAVING MORE OF A NEGATIVE TROUGH VS THE GFS. BELIEVE THE
UKMET IS A GOOD COMPROMISE AT IS WAS THE FIRST DETERMINISTIC
GUIDANCE ON TAMPERING DOWN THE FIRST MAIN LOW...WHILE THE CMC IS OUT
TO LUNCH. REGARDLESS THIS IS A VERY ANOMALOUS SYSTEM THAT IS ABOUT 4
STANDARD DEVIATIONS AWAY.

A SECONDARY SYSTEM DEEPENS ACROSS THE FOUR CORNERS ON FRIDAY AND
WITH THE STUBBORN TROUGH OVER THE CENTRAL U.S...IT WILL PUSH A
SYSTEM TOWARDS SOUTHERN NEW ENGLAND BY SUNDAY. THIS SYSTEM MAY
SUPPORT A MODEST SWATH OF OVERRUNNING SNOW OVER SOUTHERN NEW
ENGLAND.

DETAILS...

MONDAY INTO TUESDAY...MODERATE CONFIDENCE.

A WEAK WAVE OF LOW PRESSURE DEVELOPS ALONG THE SOUTHEAST COAST
MONDAY...AND WILL BE ON A DEVELOPING WARM FRONTAL BOUNDARY. THIS LOW
REMAINS WEAK AS THE WARM FRONT MOVES SLOWLY NORTH MONDAY NIGHT INTO
TUESDAY. APPEARS THAT THERE IS DECENT WARM ADVECTION AHEAD OF THIS
WAVE. SEVERAL HI-RES GUIDANCE MODELS SHOW THAT THERE IS THE
POTENTIAL FOR COLD AIR DAMMING ACROSS THE INTERIOR INTO TUESDAY.
BIGGEST QUESTION WILL BE IS THERE ENOUGH MOISTURE FOR PRECIP DURING
THIS TIME FRAME. DUE TO A STRENGTHENING LLJ PROVIDING A GOOD SOURCE OF
LIFT ANTICIPATE PRECIP TO DEVELOP AND OVERSPREAD ACROSS SOUTHERN NEW
ENGLAND. IF THIS PLAYS OUT WITH COLD AIR DAMMING AND WARM AIR
ADVECTION...THEN WE COULD SEE FREEZING RAIN/DRIZZLE ACROSS THE I-91
CORRIDOR LATE MONDAY INTO TUESDAY MORNING. DURING THE DAY ON
TUESDAY...GOOD AMOUNT OF WARM AIR WILL PUSH SURFACE TEMPS ABOVE
FREEZING BY THE LATE MORNING ALLOWING FOR ANY PRECIP TO BE MORE OF
THE LIQUID VARIETY AHEAD OF THE CHRISTMAS EVE STORM. HOWEVER
GUIDANCE IS ALWAYS TOO FAST IN SCOURING TEMPS OUT ESP ACROSS THE CT
VALLEY SO WE WILL NEED TO MONITOR THIS CLOSELY...ESP DUE TO LIGHT
WINDS AND THE HIGH IN EASTERN CANADA. A WINTER WX ADVISORY MAY BE
NEEDED FOR THE LIGHT ICING POTENTIAL.

WE COULD ALSO SEE SOME MINOR COASTAL FLOODING CONCERNS ON TUESDAY. SEE
BELOW FOR MORE DETAILS.

WEDNESDAY INTO THURSDAY...HIGH CONFIDENCE IN SYSTEM LOW CONFIDENCE
ON DETAILS.

ANOMALOUS SYSTEM WILL STRENGTHEN OVER THE GREAT LAKES TUESDAY INTO
WEDNESDAY. A SECONDARY SHORTWAVE WILL ROUND THE DEEP TROUGH AND
DEVELOP A SECONDARY LOW PRESSURE ALONG THE COLD FRONT. THIS
SECONDARY LOW WILL STRENGTHEN AND PASS WEST OF SOUTHERN NEW ENGLAND.
THIS SYSTEM WILL CONTINUE TO DEEPEN AS IT MOVES TOWARDS EASTERN
CANADA SWINGING A COLD FRONT ACROSS THE NORTHEAST.

STRONG SOUTHERLY JET OUT AHEAD OF THE FRONT WITH A GULF MOISTURE
CONNECTION WILL IMPACT SOUTHERN NEW ENGLAND ON CHRISTMAS EVE. THIS
STRONG JET WILL YIELD FOR PCPN IN THE LIQUID VARIETY.  PW ANOMALIES
ARE BETWEEN +4 TO +5 STANDARD DEVIATIONS ABOVE NORMAL WHICH IS QUITE
ANOMALOUS FOR THIS TIME OF YEAR. IN FACT CURRENT PWATS ARE PROGGED
ABOVE 1.6 INCHES WITH MODEL QPF OVER 2 INCHES...AT THE VERY LEAST
COULD SEE URBAN AND POOR DRAINAGE FLOODING. LATEST EC EVEN SHOWS
OVER 2.5 INCHES OF QPF...AND WITH THE TROPICAL CONNECTION AND STRONG
SOUTHERLY FLOW COULD SEE HIGHER AMOUNTS DUE TO TOPOGRAPHY
ENHANCEMENTS. RAINFALL RECORDS MAY FALL IF EVERYTHING FALLS INTO
PLACE.

AHEAD OF THE FRONT...SOUTHERN NEW ENGLAND WILL WARM SECTOR WED INTO
THUR MORNING ALLOWING FOR TEMPERATURES TO BE WELL ABOVE AVERAGE. IN
FACT WE MAY BE CLOSE AT BREAKING RECORD HIGH TEMPS IF TEMPS WARM TO
60F OR ABOVE ON CHRISTMAS EVE. SINCE WE WILL BE IN THE WARM
SECTOR...AND SHOWALTERS CLOSE TO ZERO...ISOLATED THUNDER IS STILL
POSSIBLE.

STRONG LOW LEVEL WINDS WILL ALSO BE A CONCERN ESPECIALLY WEDNESDAY
NIGHT. THE ECMWF SHOWS EAST-SOUTHEAST WINDS 30-40 KNOTS ON WEDNESDAY
INCREASING TO 60-75 KNOTS BY WEDNESDAY NIGHT. STRONG DOWNPOURS MAY
OVERCOME THE LOW LEVEL INVERSION AND BRING STRONG GUSTS OF AT LEAST
30-40 KNOTS ESPECIALLY ALONG THE SOUTH COAST. A WIND ADVISORY MAY BE
NEEDED IN SOME AREAS.

CHRISTMAS DAY...MODERATE CONFIDENCE.

AS THE COLD FRONT PASSES THROUGH EARLY CHRISTMAS DAY...THE WEST
WINDS WILL HELP DRY THE AIRMASS ALLOWING FOR PARTLY SUNNY SKIES.
STRONG CAA ON THURSDAY WILL ALLOW DESCENT MIXING. WINDS IN THE SFC-
850 MB LAYER WILL BE 30-40 KNOTS AND POSSIBLY A LITTLE
HIGHER...WHICH WOULD REQUIRE A WIND ADVISORY FOR MUCH OF THE AREA.

FRIDAY-SUNDAY...LOWER CONFIDENCE

WEAK HIGH PRESSURE BUILDS OVER THE AREA FRIDAY INTO SATURDAY. THE
NEXT SHORTWAVE APPROACHES LATE SATURDAY INTO SUNDAY AND SHOULD BRING
INCREASING CLOUDS FROM WEST TO EAST ALONG WITH A CHANCE OF RAIN OR
SNOW SHOWERS MAINLY IN THE AFTERNOON AND AT NIGHT.

&&

.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /TODAY AND TONIGHT/...

TODAY AND TONIGHT...MODERATE CONFIDENCE.  MAINLY MVFR CONDITIONS
SOUTH OF THE MA TURNPIKE WITH BORDERLINE VFR TO MARGINAL MVFR CIGS
NORTH OF THE PIKE THROUGH TONIGHT.  AN AREA OF SNOW SHOWERS WILL
EXPAND MAINLY ACROSS AREAS SOUTH OF THE PIKE THIS MORNING...BUT A
FEW SNOW SHOWERS WILL STILL AFFECT NORTHERN MA.  VSBYS/CIGS MAY
BRIEFLY DROP TO IFR LEVELS IN NORTHERN CT/RI/SE MA.  PTYPE WILL BE
RAIN SHOWERS ACROSS MOST OF PLYMOUTH COUNTY AND ONTO THE
CAPE/ISLANDS WITH SNOW SHOWERS NORTH AND WEST.  BULK OF PRECIP THIS
MORNING...BUT A FEW LINGERING RAIN/SNOW SHOWERS STILL POSSIBLE THIS
AFTERNOON AND EVENING.

KBOS TERMINAL...MODERATE CONFIDENCE.  A FEW SNOW SHOWERS POSSIBLE
THIS MORNING BUT BULK OF ACTIVITY SHOULD BE SOUTH OF THE TERMINAL.

KBDL TERMINAL...MODERATE CONFIDENCE.  PERIOD OF SNOW SHOWERS THIS
MORNING MAY DROP AN INCH OR TWO OF SNOW.  MVFR CONDITIONS DOMINATE
TODAY....BUT A BRIEF PERIOD OF IFR CONDITIONS ARE POSSIBLE THIS
MORNING IN SNOW SHOWERS.

OUTLOOK...MONDAY THROUGH THURSDAY...MODERATE CONFIDENCE.

MONDAY...MVFR CIGS CONTINUE IN RI/EASTERN MASS IN MARINE EAST FLOW.
VFR IN THE WEST.

TUESDAY...VFR WITH SCATTERED MVFR IN ANY RAIN/SNOW SHOWERS.

WEDNESDAY...CONDITIONS LOWERING TO IFR IN RAIN/HEAVY RAIN. ISOLATED
THUNDERSTORMS POSSIBLE ESPECIALLY WEDNESDAY NIGHT. EAST-SOUTHEAST
SURFACE WINDS MAY GUST TO 35-45 KNOTS. WINDS AT 2000 FEET AGL WILL
REACH 50-60 KNOTS WEDNESDAY AFTERNOON AND EARLY NIGHT CREATING LOW
LEVEL WIND SHEAR CONCERNS.

CHRISTMAS DAY...WEST WIND GUSTING 30-40 KNOTS. CONDITIONS IMPROVING
TO VFR AS THE WIND BRINGS IN COOLER DRIER AIR.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /TODAY AND TONIGHT/...HIGH CONFIDENCE.

HIGH PRESSURE ACROSS QUEBEC WILL RESULT IN NORTHEAST WINDS ACROSS
THE WATERS THAT WILL GUST TO BETWEEN 15 AND 20 KNOTS.  THIS WILL
RESULT IN 2 TO 4 FOOT SEAS.  HOWEVER...NO HEADLINES PLANNED AS
CONDITIONS SHOULD REMAIN BELOW SMALL CRAFT ADVISORY THRESHOLDS.

OUTLOOK...MONDAY THROUGH THURSDAY...MODERATE CONFIDENCE

MONDAY...EAST TO NORTHEAST WINDS GUSTING AROUND 15 KNOTS OR LESS.
SEAS WILL HOLD AROUND 3-4 FEET...MAY INCREASE TO 5FT IN NORTHEAST
FLOW AS GUIDANCE MAY BE UNDERDONE.

TUESDAY... INCREASING EAST WINDS WITH FREQUENT GUSTS 25 TO 30 KNOTS.
SEAS WILL BUILD TO 5-6 FEET ON THE EXPOSED WATERS.  A SMALL CRAFT
ADVISORY MAY BE NEEDED.

WEDNESDAY...RAIN WILL BE HEAVY AT TIMES PRODUCING POOR VISIBILITY.
INCREASING SOUTHEAST WINDS 20-25 SUSTAINED AND 40 KNOT GUSTS.  WINDS
SHOULD SHIFT TO SOUTH WEDNESDAY NIGHT AND SOUTHWEST TOWARD THURSDAY
MORNING. RAIN WILL TAPER OFF WITH THE WIND SHIFT TO SOUTHWEST. SEAS
WILL CONTINUE TO BUILD WITH 7-11 FEET HEIGHTS ON THE EXPOSED WATERS.
A GALE WARNING WILL BE NEEDED...WITH A LOW PROB OF A FEW STORM FORCE
GUSTS ACROSS THE EASTERN OUTER WATERS.

CHRISTMAS DAY... WEST SOUTHWEST WINDS WILL CONTINUE TO GUST 35-40
KNOTS...SO A CONTINUED GALE WARNING MAY BE NEEDED. SEAS OF 7-15 FEET
ARE POSSIBLE ON THE EXPOSED WATERS...AND 5 FEET IS POSSIBLE ON SOME
OF THE NEARSHORE WATERS.

&&

.TIDES/COASTAL FLOODING...
HIGH ASTRONOMICAL TIDES WILL OCCUR TUESDAY THROUGH THURSDAY. BREAKING
IT DOWN...ON TUESDAY HIGH TIDE AT BOSTON WILL BE 11.6 FT. THERE WILL
BE ONSHORE FLOW DURING THIS HIGH TIDE ALLOWING FOR MINOR SPLASHOVER.
IF WIND GUSTS INCREASE THEN COULD POSSIBLE SEE MINOR COASTAL
FLOODING.

ON WEDNESDAY...WINDS WILL SWITCH TO A MORE SOUTHEASTERLY FLOW DURING
THE DAY AND INCREASE QUICKLY FROM APPROACHING SYSTEM AND DECENT
PRESSURE FALLS. WEDNESDAY AFTERNOON HIGH TIDE IN BOSTON IS 11.7 FT
AND WITH ANY STRENGTH ON THE EASTERLY WIND FLOW WILL PUSH THE TIDE
OVER. RIGHT NOW BELIEVE MINOR COASTAL FLOODING IS POSSIBLE ALONG THE
EAST COASTLINE.

WEDNESDAY EVENING...THE WIND GOES IN A MORE SOUTHERLY DIRECTION AND
THE TIDE WILL BE INCREASE ACROSS THE SOUTH COAST. HIGH TIDE IN
PROVIDENCE WILL BE 5.2 FT. 925 MB LLJ STRENGTHENS TO 50-60 KTS WHICH
COULD PUSH A DECENT SURGE UP ALONG THE SOUTH COAST DURING THE TIME
OF HIGH TIDE. THINKING THAT MINOR COASTAL FLOODING COULD OCCUR BUT
CANNOT RULE OUT MODERATE ALONG THE SOUTH COAST...ESP IF LLJ
STRENGTHENS EVEN MORE.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...FRANK/DUNTEN
NEAR TERM...FRANK/DUNTEN/RLG
SHORT TERM...FRANK
LONG TERM...DUNTEN
AVIATION...FRANK/DUNTEN
MARINE...FRANK/DUNTEN
TIDES/COASTAL FLOODING...




000
FXUS61 KGYX 211432
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
932 AM EST SUN DEC 21 2014

.SYNOPSIS...
HIGH PRESSURE BUILDS OVER NORTHERN MAINE SUNDAY...ALLOWING THE
FLOW TO TURN ONSHORE. A WEAK WEATHER DISTURBANCE MAY TRIGGER SOME
FLURRIES OR LIGHT SNOW OVER SOUTHERN REGIONS RIGHT THROUGH MONDAY.
A SIGNIFICANT LOW PRESSURE SYSTEM SYSTEM WILL GRADUALLY ORGANIZE
WEDNESDAY...BEFORE MOVING OVER THE GREAT LAKES. THIS COULD BRING
WINDY CONDITIONS AND THE POTENTIAL FOR HEAVY RAIN AROUND CHRISTMAS
EVE INTO EARLY CHRISTMAS MORNING.

&&

.NEAR TERM /THROUGH TONIGHT/...
UPDATE...
HAVE UPDATED GRIDS TO RAISE POPS FROM SLIGHT CHANCE/CHANCE TO
CATEGORICAL...AT LEAST FOR THIS MORNING. LOW LEVEL MOISTURE
CONTINUES TO DEPOSIT SNOW ACROSS SOUTHERN NH AND FAR WESTERN
MAINE. WILL FORECAST 1 TO 2 INCHES OF SNOW FOR TODAY AS SOME AREAS
WILL REMAIN NEAR A MILE VSBY IN SNOW. SOME HIGHER REFLECTIVITY
RETURNS IN THE ROCHESTER NH AREA AS WELL WILL PINWHEEL SLOWLY TO
THE NE. THIS IS IN ASSOCIATION WITH AN INVERTED TROUGH OVER
SOUTHERN NEW ENGLAND AS OF 14Z WITH AN UPPER LEVEL LOW SLOWLY
CROSSING THE FORECAST AREA TODAY AS WELL. NUMERICAL MODELS SHIFT
PRECIP SOUTH AND EAST THIS AFTERNOON...WHICH IS IN DISAGREEMENT
WITH THE CURRENT RADAR ANIMATIONS.

OTHERWISE...JUST MINOR MODIFICATIONS TO THE REST OF THE GRIDED
PACKAGE.

PREV DISC...
615 AM UPDATE...JUST MADE SOME MINOR UPDATES TO SKY
AND TEMPERATURES BASED ON CURRENT OBS AND TRENDS...AS STRATUS
REMAINS ENTRENCHED ACROSS THE REGION.

PREVIOUS DISCUSSION...
LOW STRATUS BLANKETS THE CWFA AS A SURFACE HIGH PRESSURE IN
SOUTHERN QUEBEC IS HELPING TO KEEP MOISTURE TRAPPED IN THE LOW
LEVELS. A WEAK SHORTWAVE THAT IS PASSING OVER THE SOUTHERN NEW
ENGLAND THIS MORNING AND THIS MAY HELP KICK OFF SOME LIGHT SNOW
ACROSS THE FAR SOUTHERN AREAS OF NEW HAMPSHIRE AND PARTS OF
SOUTHWEST MAINE...AS ON SHORE FLOW SUPPLIES THE LOW LEVEL MOISTURE
THE LIFT FROM THIS WEAK SHORT MAY BE JUST ENOUGH TO PRODUCE SNOW
SHOWERS HEAVY ENOUGH TO ACCUMULATE IN SOME AREAS. AS THIS WEAK
WAVE MOVES EAST OUR FLOW...ALTHOUGH VERY WEAK...WILL TURN TO
NORTHWESTERLY AND THIS MAY BE ENOUGH TO START CLEARING OUT SOME OF
THE LOW STRATUS SUNDAY NIGHT.

&&

.SHORT TERM /MONDAY/...
FLOW WILL SWITCH BACK TO ON SHORE BY NOON ON MONDAY AND THIS WILL
BRING LIGHT OCEAN EFFECT SNOW OR MAYBE EVEN SOME LIGHT RAIN OR
EVEN FREEZING DRIZZLE INTO THE INTERIOR AS TEMPERATURES WILL HOVER
CLOSE TO FREEZING AS YOU GET AWAY FROM THE COAST.

&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
MODELS CONTINUE TO TREND TOWARD UPSTREAM AND DOWNSTREAM
BLOCKING...WITH AN EVENTUAL RETURN TO A +PNA PATTERN AT
500MB...WHICH WOULD SIGNAL COOLING LATE IN THE PERIOD. HOWEVER
ALL THE ACTION WILL BE IN DAYS 3 TO 5 AS THE UPSTREAM DEVELOPS AND
SENDS WAVES INTO TROUGH OVER CENTRAL CONUS...AMPLIFYING THE 500
MB FLOW.

INITIALLY...WILL BE DEALING WITH SMALLER SCALE FEATURE AS
INVERTED TROUGH OVER THE GULF OF ME WORK ITS WAY ONSHORE MON NIGHT
AND WEAKENS. MAY BE ENOUGH DYNAMIC FORCING FOR ICE CRYSTALS
INITIALLY...SO RAIN OR SNOW SHOWERS MOVE ONSHORE AND INLAND DURING
THE EVENING...BUT COULD SEE IT TURN TO DZ/FZDZ AS WE WE JUST
TRANSPORT WATER DROPLETS ONSHORE. WE MAINTAIN AN ONSHORE FLOW INTO
TUESDAY...BUT IT LOOKS LIKE FORCING WILL BE LIMITED TO
UPSLOPE...SO THINKING MORE IN THE WAY OF SHSN/SHRA/VERY LIGHT SNOW
INLAND...WITH JUST CLOUDS ON THE COAST. SHOULD SEE TEMPS ON TUE
WARM INTO THE UPPER 30S TO MID 40S.

THE MAIN EVENT REMAINS THE IMPRESSIVE 500 MB TROUGH THAT DEVELOPS
OVER THE CENTRAL CONUS MID WEEK...NOT SO MUCH IN THAT IT IS VERY
DEEP...BUT MORE ITS AMPLITUDE AS IT EXTENDS FROM N OF THE GREAT
LAKES SWD INTO THE GULF OF MEX....AND THEN TILTS VERY NEG AND
LIFTS POLEWARD WED NIGHT AND THU. NOT SURE HOW MUCH AN EFFECT
CONVECTIVE SCALING ISSUES ARE HAVING ON THE MODELS...BUT IT MAY BE
HAVING SOME EFFECT ON THE FORECAST DETAILS...BUT PROB NOT THE
GENERALITIES OF THE FORECAST. HOWEVER...00Z EURO AND GFS BOTH SHOW
A WEAKER SFC LOW IN THE VCNITY OF THE GRT LAKES AND ST LAWRENCE
VLY /ALTHOUGH IT DOES INTENSIFY FURTHER N AND E THAN PREV MODEL
RUNS. STILL...AS THAT WAVE LIFTS NWD WILL SEE TRIPLE POINT DEVELOP
OVER THE MID ATLANTIC WED EVE...AND LIFT NNE INTO THE CWA BY THU
MORNING. THIS WILL CREATE A DEEP SOUTHERLY FLOW WHICH WILL CONNECT
WITH GULF MOISTURE...ALLOWING FOR SIGNIFICANT RAINFALL...FROM
LATE IN THE DAY WED...INTO EARLY THU MORNING. QPF LOOKS TO RUN
AROUND 2-3 INCHES IN MANY SPOTS...BUT S-SE UPSLOPE AREAS OF THE
FOOTHILLS AND MTNS COULD SEE AN INCH OR TWO MORE...SO THE THREAT
OF BOTH FLASH AND MAINSTEM FLOODING IS A CONCERN...ESPECIALLY
SINCE THIS WILL BE COMBINE WITH SIGNIFICANT SNOWMELT AS HIGHS
RISE WELL INTO THE 40S WED..AND WILL LKLY STAY THERE WED NIGHT
INTO THU.

THERE IS STILL THE POTENTIAL FOR SOME STRONG GUSTS...BUT GIVEN
WEAKER SYSTEM...THE WINDOW FOR OPPORTUNITY WILL BE LIMITED TO A
FE HOURS AHEAD OF THE TRIPLE POINT PASSAGE...WHICH LOOKS TO BE WED
EVE...AT LEAST FOR NOW. WITH ALL THAT SAID...WE ARE STILL DEALING
WITH DAYS 4 AND 5 OF THE FORECAST...WITH THE POTENTIAL FRO SOME
DEEP CONVECTION IN THE BASE OF THE TROUGH...SO FORECAST COULD
CHANGE...BUT BOTH EURO AND GFS PICKED UP THE SIGNALS OF THIS
SYSTEM EARLY...AND HAVE BEEN CONSISTENT ON THE WHOLE SO FAR.

CHRISTMAS DAY WILL SEE RAIN ENDING FROM SW TO NE DURING THE
MORNING...WITH SOME PARTIAL CLEARING POSSIBLE IN THE
AFTERNOON...AND TEMPS IN THE 40S AGAIN. COOLER AIR WILL MOVE IN
FROM THE SW THU NIGHT. FRI AND SAT LOOK MOSTLY DRY /OTHER THAN
POSSIBLE UPSLOPE SHSN ON FRI/. HIGHS WILL CONTINUE TO RUN A FEW
DEGREES ABV NORMAL.

&&

.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
SHORT TERM...MVFR TO IFR CEILINGS WILL REMAIN OVER THE REGION
THROUGH AT LEAST SUNDAY EVENING. CONDITIONS MAY IMPROVE A BIT
SUNDAY NIGHT AS THE ON SHORE FLOW DRIFTING MOISTURE INLAND WILL
GET SHUT OFF. CONDITIONS WILL NOT STAY UP LONG HOWEVER AS THE FLOW
WILL SWITCH BACK TO ON SHORE ON MONDAY BRINGING ANOTHER ROUND OF
MVFR TO IFR CEILINGS.

LONG TERM...POSSIBLE PERIODS OF MVFR TO IFR MONDAY NIGHT AS
INVERTED TROUGH MOVES INLAND. MVFR LIKELY TO HOLD TUESDAY INTO
TUESDAY NIGHT...LOWERING TO IFR LATE TUESDAY NIGHT INTO THURSDAY
MORNING IN RAIN...WITH INCREASING E-SE WINDS WEDNESDAY.

&&

.MARINE...
SHORT TERM...A FEW WIND GUSTS CONTINUE JUST BELOW 25 KTS THIS
AFTERNOON...WITH WAVES 4` OR LOWER...THEREFORE NO FLAGS IN THE
NEAR TERM. WINDS SHOULD CONTINUE TO SLOWLY DECREASE TONIGHT INTO
TOMORROW FROM THE NORTHEAST.

LONG TERM...HIGH PRESSURE WITH LIGHT AND FAIRLY CALM SEAS WILL
PERSIST THROUGH THE PERIOD AND NO FLAGS ARE EXPECTED.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.

&&

$$
JC



000
FXUS61 KGYX 211432
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
932 AM EST SUN DEC 21 2014

.SYNOPSIS...
HIGH PRESSURE BUILDS OVER NORTHERN MAINE SUNDAY...ALLOWING THE
FLOW TO TURN ONSHORE. A WEAK WEATHER DISTURBANCE MAY TRIGGER SOME
FLURRIES OR LIGHT SNOW OVER SOUTHERN REGIONS RIGHT THROUGH MONDAY.
A SIGNIFICANT LOW PRESSURE SYSTEM SYSTEM WILL GRADUALLY ORGANIZE
WEDNESDAY...BEFORE MOVING OVER THE GREAT LAKES. THIS COULD BRING
WINDY CONDITIONS AND THE POTENTIAL FOR HEAVY RAIN AROUND CHRISTMAS
EVE INTO EARLY CHRISTMAS MORNING.

&&

.NEAR TERM /THROUGH TONIGHT/...
UPDATE...
HAVE UPDATED GRIDS TO RAISE POPS FROM SLIGHT CHANCE/CHANCE TO
CATEGORICAL...AT LEAST FOR THIS MORNING. LOW LEVEL MOISTURE
CONTINUES TO DEPOSIT SNOW ACROSS SOUTHERN NH AND FAR WESTERN
MAINE. WILL FORECAST 1 TO 2 INCHES OF SNOW FOR TODAY AS SOME AREAS
WILL REMAIN NEAR A MILE VSBY IN SNOW. SOME HIGHER REFLECTIVITY
RETURNS IN THE ROCHESTER NH AREA AS WELL WILL PINWHEEL SLOWLY TO
THE NE. THIS IS IN ASSOCIATION WITH AN INVERTED TROUGH OVER
SOUTHERN NEW ENGLAND AS OF 14Z WITH AN UPPER LEVEL LOW SLOWLY
CROSSING THE FORECAST AREA TODAY AS WELL. NUMERICAL MODELS SHIFT
PRECIP SOUTH AND EAST THIS AFTERNOON...WHICH IS IN DISAGREEMENT
WITH THE CURRENT RADAR ANIMATIONS.

OTHERWISE...JUST MINOR MODIFICATIONS TO THE REST OF THE GRIDED
PACKAGE.

PREV DISC...
615 AM UPDATE...JUST MADE SOME MINOR UPDATES TO SKY
AND TEMPERATURES BASED ON CURRENT OBS AND TRENDS...AS STRATUS
REMAINS ENTRENCHED ACROSS THE REGION.

PREVIOUS DISCUSSION...
LOW STRATUS BLANKETS THE CWFA AS A SURFACE HIGH PRESSURE IN
SOUTHERN QUEBEC IS HELPING TO KEEP MOISTURE TRAPPED IN THE LOW
LEVELS. A WEAK SHORTWAVE THAT IS PASSING OVER THE SOUTHERN NEW
ENGLAND THIS MORNING AND THIS MAY HELP KICK OFF SOME LIGHT SNOW
ACROSS THE FAR SOUTHERN AREAS OF NEW HAMPSHIRE AND PARTS OF
SOUTHWEST MAINE...AS ON SHORE FLOW SUPPLIES THE LOW LEVEL MOISTURE
THE LIFT FROM THIS WEAK SHORT MAY BE JUST ENOUGH TO PRODUCE SNOW
SHOWERS HEAVY ENOUGH TO ACCUMULATE IN SOME AREAS. AS THIS WEAK
WAVE MOVES EAST OUR FLOW...ALTHOUGH VERY WEAK...WILL TURN TO
NORTHWESTERLY AND THIS MAY BE ENOUGH TO START CLEARING OUT SOME OF
THE LOW STRATUS SUNDAY NIGHT.

&&

.SHORT TERM /MONDAY/...
FLOW WILL SWITCH BACK TO ON SHORE BY NOON ON MONDAY AND THIS WILL
BRING LIGHT OCEAN EFFECT SNOW OR MAYBE EVEN SOME LIGHT RAIN OR
EVEN FREEZING DRIZZLE INTO THE INTERIOR AS TEMPERATURES WILL HOVER
CLOSE TO FREEZING AS YOU GET AWAY FROM THE COAST.

&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
MODELS CONTINUE TO TREND TOWARD UPSTREAM AND DOWNSTREAM
BLOCKING...WITH AN EVENTUAL RETURN TO A +PNA PATTERN AT
500MB...WHICH WOULD SIGNAL COOLING LATE IN THE PERIOD. HOWEVER
ALL THE ACTION WILL BE IN DAYS 3 TO 5 AS THE UPSTREAM DEVELOPS AND
SENDS WAVES INTO TROUGH OVER CENTRAL CONUS...AMPLIFYING THE 500
MB FLOW.

INITIALLY...WILL BE DEALING WITH SMALLER SCALE FEATURE AS
INVERTED TROUGH OVER THE GULF OF ME WORK ITS WAY ONSHORE MON NIGHT
AND WEAKENS. MAY BE ENOUGH DYNAMIC FORCING FOR ICE CRYSTALS
INITIALLY...SO RAIN OR SNOW SHOWERS MOVE ONSHORE AND INLAND DURING
THE EVENING...BUT COULD SEE IT TURN TO DZ/FZDZ AS WE WE JUST
TRANSPORT WATER DROPLETS ONSHORE. WE MAINTAIN AN ONSHORE FLOW INTO
TUESDAY...BUT IT LOOKS LIKE FORCING WILL BE LIMITED TO
UPSLOPE...SO THINKING MORE IN THE WAY OF SHSN/SHRA/VERY LIGHT SNOW
INLAND...WITH JUST CLOUDS ON THE COAST. SHOULD SEE TEMPS ON TUE
WARM INTO THE UPPER 30S TO MID 40S.

THE MAIN EVENT REMAINS THE IMPRESSIVE 500 MB TROUGH THAT DEVELOPS
OVER THE CENTRAL CONUS MID WEEK...NOT SO MUCH IN THAT IT IS VERY
DEEP...BUT MORE ITS AMPLITUDE AS IT EXTENDS FROM N OF THE GREAT
LAKES SWD INTO THE GULF OF MEX....AND THEN TILTS VERY NEG AND
LIFTS POLEWARD WED NIGHT AND THU. NOT SURE HOW MUCH AN EFFECT
CONVECTIVE SCALING ISSUES ARE HAVING ON THE MODELS...BUT IT MAY BE
HAVING SOME EFFECT ON THE FORECAST DETAILS...BUT PROB NOT THE
GENERALITIES OF THE FORECAST. HOWEVER...00Z EURO AND GFS BOTH SHOW
A WEAKER SFC LOW IN THE VCNITY OF THE GRT LAKES AND ST LAWRENCE
VLY /ALTHOUGH IT DOES INTENSIFY FURTHER N AND E THAN PREV MODEL
RUNS. STILL...AS THAT WAVE LIFTS NWD WILL SEE TRIPLE POINT DEVELOP
OVER THE MID ATLANTIC WED EVE...AND LIFT NNE INTO THE CWA BY THU
MORNING. THIS WILL CREATE A DEEP SOUTHERLY FLOW WHICH WILL CONNECT
WITH GULF MOISTURE...ALLOWING FOR SIGNIFICANT RAINFALL...FROM
LATE IN THE DAY WED...INTO EARLY THU MORNING. QPF LOOKS TO RUN
AROUND 2-3 INCHES IN MANY SPOTS...BUT S-SE UPSLOPE AREAS OF THE
FOOTHILLS AND MTNS COULD SEE AN INCH OR TWO MORE...SO THE THREAT
OF BOTH FLASH AND MAINSTEM FLOODING IS A CONCERN...ESPECIALLY
SINCE THIS WILL BE COMBINE WITH SIGNIFICANT SNOWMELT AS HIGHS
RISE WELL INTO THE 40S WED..AND WILL LKLY STAY THERE WED NIGHT
INTO THU.

THERE IS STILL THE POTENTIAL FOR SOME STRONG GUSTS...BUT GIVEN
WEAKER SYSTEM...THE WINDOW FOR OPPORTUNITY WILL BE LIMITED TO A
FE HOURS AHEAD OF THE TRIPLE POINT PASSAGE...WHICH LOOKS TO BE WED
EVE...AT LEAST FOR NOW. WITH ALL THAT SAID...WE ARE STILL DEALING
WITH DAYS 4 AND 5 OF THE FORECAST...WITH THE POTENTIAL FRO SOME
DEEP CONVECTION IN THE BASE OF THE TROUGH...SO FORECAST COULD
CHANGE...BUT BOTH EURO AND GFS PICKED UP THE SIGNALS OF THIS
SYSTEM EARLY...AND HAVE BEEN CONSISTENT ON THE WHOLE SO FAR.

CHRISTMAS DAY WILL SEE RAIN ENDING FROM SW TO NE DURING THE
MORNING...WITH SOME PARTIAL CLEARING POSSIBLE IN THE
AFTERNOON...AND TEMPS IN THE 40S AGAIN. COOLER AIR WILL MOVE IN
FROM THE SW THU NIGHT. FRI AND SAT LOOK MOSTLY DRY /OTHER THAN
POSSIBLE UPSLOPE SHSN ON FRI/. HIGHS WILL CONTINUE TO RUN A FEW
DEGREES ABV NORMAL.

&&

.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
SHORT TERM...MVFR TO IFR CEILINGS WILL REMAIN OVER THE REGION
THROUGH AT LEAST SUNDAY EVENING. CONDITIONS MAY IMPROVE A BIT
SUNDAY NIGHT AS THE ON SHORE FLOW DRIFTING MOISTURE INLAND WILL
GET SHUT OFF. CONDITIONS WILL NOT STAY UP LONG HOWEVER AS THE FLOW
WILL SWITCH BACK TO ON SHORE ON MONDAY BRINGING ANOTHER ROUND OF
MVFR TO IFR CEILINGS.

LONG TERM...POSSIBLE PERIODS OF MVFR TO IFR MONDAY NIGHT AS
INVERTED TROUGH MOVES INLAND. MVFR LIKELY TO HOLD TUESDAY INTO
TUESDAY NIGHT...LOWERING TO IFR LATE TUESDAY NIGHT INTO THURSDAY
MORNING IN RAIN...WITH INCREASING E-SE WINDS WEDNESDAY.

&&

.MARINE...
SHORT TERM...A FEW WIND GUSTS CONTINUE JUST BELOW 25 KTS THIS
AFTERNOON...WITH WAVES 4` OR LOWER...THEREFORE NO FLAGS IN THE
NEAR TERM. WINDS SHOULD CONTINUE TO SLOWLY DECREASE TONIGHT INTO
TOMORROW FROM THE NORTHEAST.

LONG TERM...HIGH PRESSURE WITH LIGHT AND FAIRLY CALM SEAS WILL
PERSIST THROUGH THE PERIOD AND NO FLAGS ARE EXPECTED.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.

&&

$$
JC



000
FXUS61 KGYX 211432
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
932 AM EST SUN DEC 21 2014

.SYNOPSIS...
HIGH PRESSURE BUILDS OVER NORTHERN MAINE SUNDAY...ALLOWING THE
FLOW TO TURN ONSHORE. A WEAK WEATHER DISTURBANCE MAY TRIGGER SOME
FLURRIES OR LIGHT SNOW OVER SOUTHERN REGIONS RIGHT THROUGH MONDAY.
A SIGNIFICANT LOW PRESSURE SYSTEM SYSTEM WILL GRADUALLY ORGANIZE
WEDNESDAY...BEFORE MOVING OVER THE GREAT LAKES. THIS COULD BRING
WINDY CONDITIONS AND THE POTENTIAL FOR HEAVY RAIN AROUND CHRISTMAS
EVE INTO EARLY CHRISTMAS MORNING.

&&

.NEAR TERM /THROUGH TONIGHT/...
UPDATE...
HAVE UPDATED GRIDS TO RAISE POPS FROM SLIGHT CHANCE/CHANCE TO
CATEGORICAL...AT LEAST FOR THIS MORNING. LOW LEVEL MOISTURE
CONTINUES TO DEPOSIT SNOW ACROSS SOUTHERN NH AND FAR WESTERN
MAINE. WILL FORECAST 1 TO 2 INCHES OF SNOW FOR TODAY AS SOME AREAS
WILL REMAIN NEAR A MILE VSBY IN SNOW. SOME HIGHER REFLECTIVITY
RETURNS IN THE ROCHESTER NH AREA AS WELL WILL PINWHEEL SLOWLY TO
THE NE. THIS IS IN ASSOCIATION WITH AN INVERTED TROUGH OVER
SOUTHERN NEW ENGLAND AS OF 14Z WITH AN UPPER LEVEL LOW SLOWLY
CROSSING THE FORECAST AREA TODAY AS WELL. NUMERICAL MODELS SHIFT
PRECIP SOUTH AND EAST THIS AFTERNOON...WHICH IS IN DISAGREEMENT
WITH THE CURRENT RADAR ANIMATIONS.

OTHERWISE...JUST MINOR MODIFICATIONS TO THE REST OF THE GRIDED
PACKAGE.

PREV DISC...
615 AM UPDATE...JUST MADE SOME MINOR UPDATES TO SKY
AND TEMPERATURES BASED ON CURRENT OBS AND TRENDS...AS STRATUS
REMAINS ENTRENCHED ACROSS THE REGION.

PREVIOUS DISCUSSION...
LOW STRATUS BLANKETS THE CWFA AS A SURFACE HIGH PRESSURE IN
SOUTHERN QUEBEC IS HELPING TO KEEP MOISTURE TRAPPED IN THE LOW
LEVELS. A WEAK SHORTWAVE THAT IS PASSING OVER THE SOUTHERN NEW
ENGLAND THIS MORNING AND THIS MAY HELP KICK OFF SOME LIGHT SNOW
ACROSS THE FAR SOUTHERN AREAS OF NEW HAMPSHIRE AND PARTS OF
SOUTHWEST MAINE...AS ON SHORE FLOW SUPPLIES THE LOW LEVEL MOISTURE
THE LIFT FROM THIS WEAK SHORT MAY BE JUST ENOUGH TO PRODUCE SNOW
SHOWERS HEAVY ENOUGH TO ACCUMULATE IN SOME AREAS. AS THIS WEAK
WAVE MOVES EAST OUR FLOW...ALTHOUGH VERY WEAK...WILL TURN TO
NORTHWESTERLY AND THIS MAY BE ENOUGH TO START CLEARING OUT SOME OF
THE LOW STRATUS SUNDAY NIGHT.

&&

.SHORT TERM /MONDAY/...
FLOW WILL SWITCH BACK TO ON SHORE BY NOON ON MONDAY AND THIS WILL
BRING LIGHT OCEAN EFFECT SNOW OR MAYBE EVEN SOME LIGHT RAIN OR
EVEN FREEZING DRIZZLE INTO THE INTERIOR AS TEMPERATURES WILL HOVER
CLOSE TO FREEZING AS YOU GET AWAY FROM THE COAST.

&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
MODELS CONTINUE TO TREND TOWARD UPSTREAM AND DOWNSTREAM
BLOCKING...WITH AN EVENTUAL RETURN TO A +PNA PATTERN AT
500MB...WHICH WOULD SIGNAL COOLING LATE IN THE PERIOD. HOWEVER
ALL THE ACTION WILL BE IN DAYS 3 TO 5 AS THE UPSTREAM DEVELOPS AND
SENDS WAVES INTO TROUGH OVER CENTRAL CONUS...AMPLIFYING THE 500
MB FLOW.

INITIALLY...WILL BE DEALING WITH SMALLER SCALE FEATURE AS
INVERTED TROUGH OVER THE GULF OF ME WORK ITS WAY ONSHORE MON NIGHT
AND WEAKENS. MAY BE ENOUGH DYNAMIC FORCING FOR ICE CRYSTALS
INITIALLY...SO RAIN OR SNOW SHOWERS MOVE ONSHORE AND INLAND DURING
THE EVENING...BUT COULD SEE IT TURN TO DZ/FZDZ AS WE WE JUST
TRANSPORT WATER DROPLETS ONSHORE. WE MAINTAIN AN ONSHORE FLOW INTO
TUESDAY...BUT IT LOOKS LIKE FORCING WILL BE LIMITED TO
UPSLOPE...SO THINKING MORE IN THE WAY OF SHSN/SHRA/VERY LIGHT SNOW
INLAND...WITH JUST CLOUDS ON THE COAST. SHOULD SEE TEMPS ON TUE
WARM INTO THE UPPER 30S TO MID 40S.

THE MAIN EVENT REMAINS THE IMPRESSIVE 500 MB TROUGH THAT DEVELOPS
OVER THE CENTRAL CONUS MID WEEK...NOT SO MUCH IN THAT IT IS VERY
DEEP...BUT MORE ITS AMPLITUDE AS IT EXTENDS FROM N OF THE GREAT
LAKES SWD INTO THE GULF OF MEX....AND THEN TILTS VERY NEG AND
LIFTS POLEWARD WED NIGHT AND THU. NOT SURE HOW MUCH AN EFFECT
CONVECTIVE SCALING ISSUES ARE HAVING ON THE MODELS...BUT IT MAY BE
HAVING SOME EFFECT ON THE FORECAST DETAILS...BUT PROB NOT THE
GENERALITIES OF THE FORECAST. HOWEVER...00Z EURO AND GFS BOTH SHOW
A WEAKER SFC LOW IN THE VCNITY OF THE GRT LAKES AND ST LAWRENCE
VLY /ALTHOUGH IT DOES INTENSIFY FURTHER N AND E THAN PREV MODEL
RUNS. STILL...AS THAT WAVE LIFTS NWD WILL SEE TRIPLE POINT DEVELOP
OVER THE MID ATLANTIC WED EVE...AND LIFT NNE INTO THE CWA BY THU
MORNING. THIS WILL CREATE A DEEP SOUTHERLY FLOW WHICH WILL CONNECT
WITH GULF MOISTURE...ALLOWING FOR SIGNIFICANT RAINFALL...FROM
LATE IN THE DAY WED...INTO EARLY THU MORNING. QPF LOOKS TO RUN
AROUND 2-3 INCHES IN MANY SPOTS...BUT S-SE UPSLOPE AREAS OF THE
FOOTHILLS AND MTNS COULD SEE AN INCH OR TWO MORE...SO THE THREAT
OF BOTH FLASH AND MAINSTEM FLOODING IS A CONCERN...ESPECIALLY
SINCE THIS WILL BE COMBINE WITH SIGNIFICANT SNOWMELT AS HIGHS
RISE WELL INTO THE 40S WED..AND WILL LKLY STAY THERE WED NIGHT
INTO THU.

THERE IS STILL THE POTENTIAL FOR SOME STRONG GUSTS...BUT GIVEN
WEAKER SYSTEM...THE WINDOW FOR OPPORTUNITY WILL BE LIMITED TO A
FE HOURS AHEAD OF THE TRIPLE POINT PASSAGE...WHICH LOOKS TO BE WED
EVE...AT LEAST FOR NOW. WITH ALL THAT SAID...WE ARE STILL DEALING
WITH DAYS 4 AND 5 OF THE FORECAST...WITH THE POTENTIAL FRO SOME
DEEP CONVECTION IN THE BASE OF THE TROUGH...SO FORECAST COULD
CHANGE...BUT BOTH EURO AND GFS PICKED UP THE SIGNALS OF THIS
SYSTEM EARLY...AND HAVE BEEN CONSISTENT ON THE WHOLE SO FAR.

CHRISTMAS DAY WILL SEE RAIN ENDING FROM SW TO NE DURING THE
MORNING...WITH SOME PARTIAL CLEARING POSSIBLE IN THE
AFTERNOON...AND TEMPS IN THE 40S AGAIN. COOLER AIR WILL MOVE IN
FROM THE SW THU NIGHT. FRI AND SAT LOOK MOSTLY DRY /OTHER THAN
POSSIBLE UPSLOPE SHSN ON FRI/. HIGHS WILL CONTINUE TO RUN A FEW
DEGREES ABV NORMAL.

&&

.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
SHORT TERM...MVFR TO IFR CEILINGS WILL REMAIN OVER THE REGION
THROUGH AT LEAST SUNDAY EVENING. CONDITIONS MAY IMPROVE A BIT
SUNDAY NIGHT AS THE ON SHORE FLOW DRIFTING MOISTURE INLAND WILL
GET SHUT OFF. CONDITIONS WILL NOT STAY UP LONG HOWEVER AS THE FLOW
WILL SWITCH BACK TO ON SHORE ON MONDAY BRINGING ANOTHER ROUND OF
MVFR TO IFR CEILINGS.

LONG TERM...POSSIBLE PERIODS OF MVFR TO IFR MONDAY NIGHT AS
INVERTED TROUGH MOVES INLAND. MVFR LIKELY TO HOLD TUESDAY INTO
TUESDAY NIGHT...LOWERING TO IFR LATE TUESDAY NIGHT INTO THURSDAY
MORNING IN RAIN...WITH INCREASING E-SE WINDS WEDNESDAY.

&&

.MARINE...
SHORT TERM...A FEW WIND GUSTS CONTINUE JUST BELOW 25 KTS THIS
AFTERNOON...WITH WAVES 4` OR LOWER...THEREFORE NO FLAGS IN THE
NEAR TERM. WINDS SHOULD CONTINUE TO SLOWLY DECREASE TONIGHT INTO
TOMORROW FROM THE NORTHEAST.

LONG TERM...HIGH PRESSURE WITH LIGHT AND FAIRLY CALM SEAS WILL
PERSIST THROUGH THE PERIOD AND NO FLAGS ARE EXPECTED.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.

&&

$$
JC



000
FXUS61 KGYX 211432
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
932 AM EST SUN DEC 21 2014

.SYNOPSIS...
HIGH PRESSURE BUILDS OVER NORTHERN MAINE SUNDAY...ALLOWING THE
FLOW TO TURN ONSHORE. A WEAK WEATHER DISTURBANCE MAY TRIGGER SOME
FLURRIES OR LIGHT SNOW OVER SOUTHERN REGIONS RIGHT THROUGH MONDAY.
A SIGNIFICANT LOW PRESSURE SYSTEM SYSTEM WILL GRADUALLY ORGANIZE
WEDNESDAY...BEFORE MOVING OVER THE GREAT LAKES. THIS COULD BRING
WINDY CONDITIONS AND THE POTENTIAL FOR HEAVY RAIN AROUND CHRISTMAS
EVE INTO EARLY CHRISTMAS MORNING.

&&

.NEAR TERM /THROUGH TONIGHT/...
UPDATE...
HAVE UPDATED GRIDS TO RAISE POPS FROM SLIGHT CHANCE/CHANCE TO
CATEGORICAL...AT LEAST FOR THIS MORNING. LOW LEVEL MOISTURE
CONTINUES TO DEPOSIT SNOW ACROSS SOUTHERN NH AND FAR WESTERN
MAINE. WILL FORECAST 1 TO 2 INCHES OF SNOW FOR TODAY AS SOME AREAS
WILL REMAIN NEAR A MILE VSBY IN SNOW. SOME HIGHER REFLECTIVITY
RETURNS IN THE ROCHESTER NH AREA AS WELL WILL PINWHEEL SLOWLY TO
THE NE. THIS IS IN ASSOCIATION WITH AN INVERTED TROUGH OVER
SOUTHERN NEW ENGLAND AS OF 14Z WITH AN UPPER LEVEL LOW SLOWLY
CROSSING THE FORECAST AREA TODAY AS WELL. NUMERICAL MODELS SHIFT
PRECIP SOUTH AND EAST THIS AFTERNOON...WHICH IS IN DISAGREEMENT
WITH THE CURRENT RADAR ANIMATIONS.

OTHERWISE...JUST MINOR MODIFICATIONS TO THE REST OF THE GRIDED
PACKAGE.

PREV DISC...
615 AM UPDATE...JUST MADE SOME MINOR UPDATES TO SKY
AND TEMPERATURES BASED ON CURRENT OBS AND TRENDS...AS STRATUS
REMAINS ENTRENCHED ACROSS THE REGION.

PREVIOUS DISCUSSION...
LOW STRATUS BLANKETS THE CWFA AS A SURFACE HIGH PRESSURE IN
SOUTHERN QUEBEC IS HELPING TO KEEP MOISTURE TRAPPED IN THE LOW
LEVELS. A WEAK SHORTWAVE THAT IS PASSING OVER THE SOUTHERN NEW
ENGLAND THIS MORNING AND THIS MAY HELP KICK OFF SOME LIGHT SNOW
ACROSS THE FAR SOUTHERN AREAS OF NEW HAMPSHIRE AND PARTS OF
SOUTHWEST MAINE...AS ON SHORE FLOW SUPPLIES THE LOW LEVEL MOISTURE
THE LIFT FROM THIS WEAK SHORT MAY BE JUST ENOUGH TO PRODUCE SNOW
SHOWERS HEAVY ENOUGH TO ACCUMULATE IN SOME AREAS. AS THIS WEAK
WAVE MOVES EAST OUR FLOW...ALTHOUGH VERY WEAK...WILL TURN TO
NORTHWESTERLY AND THIS MAY BE ENOUGH TO START CLEARING OUT SOME OF
THE LOW STRATUS SUNDAY NIGHT.

&&

.SHORT TERM /MONDAY/...
FLOW WILL SWITCH BACK TO ON SHORE BY NOON ON MONDAY AND THIS WILL
BRING LIGHT OCEAN EFFECT SNOW OR MAYBE EVEN SOME LIGHT RAIN OR
EVEN FREEZING DRIZZLE INTO THE INTERIOR AS TEMPERATURES WILL HOVER
CLOSE TO FREEZING AS YOU GET AWAY FROM THE COAST.

&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
MODELS CONTINUE TO TREND TOWARD UPSTREAM AND DOWNSTREAM
BLOCKING...WITH AN EVENTUAL RETURN TO A +PNA PATTERN AT
500MB...WHICH WOULD SIGNAL COOLING LATE IN THE PERIOD. HOWEVER
ALL THE ACTION WILL BE IN DAYS 3 TO 5 AS THE UPSTREAM DEVELOPS AND
SENDS WAVES INTO TROUGH OVER CENTRAL CONUS...AMPLIFYING THE 500
MB FLOW.

INITIALLY...WILL BE DEALING WITH SMALLER SCALE FEATURE AS
INVERTED TROUGH OVER THE GULF OF ME WORK ITS WAY ONSHORE MON NIGHT
AND WEAKENS. MAY BE ENOUGH DYNAMIC FORCING FOR ICE CRYSTALS
INITIALLY...SO RAIN OR SNOW SHOWERS MOVE ONSHORE AND INLAND DURING
THE EVENING...BUT COULD SEE IT TURN TO DZ/FZDZ AS WE WE JUST
TRANSPORT WATER DROPLETS ONSHORE. WE MAINTAIN AN ONSHORE FLOW INTO
TUESDAY...BUT IT LOOKS LIKE FORCING WILL BE LIMITED TO
UPSLOPE...SO THINKING MORE IN THE WAY OF SHSN/SHRA/VERY LIGHT SNOW
INLAND...WITH JUST CLOUDS ON THE COAST. SHOULD SEE TEMPS ON TUE
WARM INTO THE UPPER 30S TO MID 40S.

THE MAIN EVENT REMAINS THE IMPRESSIVE 500 MB TROUGH THAT DEVELOPS
OVER THE CENTRAL CONUS MID WEEK...NOT SO MUCH IN THAT IT IS VERY
DEEP...BUT MORE ITS AMPLITUDE AS IT EXTENDS FROM N OF THE GREAT
LAKES SWD INTO THE GULF OF MEX....AND THEN TILTS VERY NEG AND
LIFTS POLEWARD WED NIGHT AND THU. NOT SURE HOW MUCH AN EFFECT
CONVECTIVE SCALING ISSUES ARE HAVING ON THE MODELS...BUT IT MAY BE
HAVING SOME EFFECT ON THE FORECAST DETAILS...BUT PROB NOT THE
GENERALITIES OF THE FORECAST. HOWEVER...00Z EURO AND GFS BOTH SHOW
A WEAKER SFC LOW IN THE VCNITY OF THE GRT LAKES AND ST LAWRENCE
VLY /ALTHOUGH IT DOES INTENSIFY FURTHER N AND E THAN PREV MODEL
RUNS. STILL...AS THAT WAVE LIFTS NWD WILL SEE TRIPLE POINT DEVELOP
OVER THE MID ATLANTIC WED EVE...AND LIFT NNE INTO THE CWA BY THU
MORNING. THIS WILL CREATE A DEEP SOUTHERLY FLOW WHICH WILL CONNECT
WITH GULF MOISTURE...ALLOWING FOR SIGNIFICANT RAINFALL...FROM
LATE IN THE DAY WED...INTO EARLY THU MORNING. QPF LOOKS TO RUN
AROUND 2-3 INCHES IN MANY SPOTS...BUT S-SE UPSLOPE AREAS OF THE
FOOTHILLS AND MTNS COULD SEE AN INCH OR TWO MORE...SO THE THREAT
OF BOTH FLASH AND MAINSTEM FLOODING IS A CONCERN...ESPECIALLY
SINCE THIS WILL BE COMBINE WITH SIGNIFICANT SNOWMELT AS HIGHS
RISE WELL INTO THE 40S WED..AND WILL LKLY STAY THERE WED NIGHT
INTO THU.

THERE IS STILL THE POTENTIAL FOR SOME STRONG GUSTS...BUT GIVEN
WEAKER SYSTEM...THE WINDOW FOR OPPORTUNITY WILL BE LIMITED TO A
FE HOURS AHEAD OF THE TRIPLE POINT PASSAGE...WHICH LOOKS TO BE WED
EVE...AT LEAST FOR NOW. WITH ALL THAT SAID...WE ARE STILL DEALING
WITH DAYS 4 AND 5 OF THE FORECAST...WITH THE POTENTIAL FRO SOME
DEEP CONVECTION IN THE BASE OF THE TROUGH...SO FORECAST COULD
CHANGE...BUT BOTH EURO AND GFS PICKED UP THE SIGNALS OF THIS
SYSTEM EARLY...AND HAVE BEEN CONSISTENT ON THE WHOLE SO FAR.

CHRISTMAS DAY WILL SEE RAIN ENDING FROM SW TO NE DURING THE
MORNING...WITH SOME PARTIAL CLEARING POSSIBLE IN THE
AFTERNOON...AND TEMPS IN THE 40S AGAIN. COOLER AIR WILL MOVE IN
FROM THE SW THU NIGHT. FRI AND SAT LOOK MOSTLY DRY /OTHER THAN
POSSIBLE UPSLOPE SHSN ON FRI/. HIGHS WILL CONTINUE TO RUN A FEW
DEGREES ABV NORMAL.

&&

.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
SHORT TERM...MVFR TO IFR CEILINGS WILL REMAIN OVER THE REGION
THROUGH AT LEAST SUNDAY EVENING. CONDITIONS MAY IMPROVE A BIT
SUNDAY NIGHT AS THE ON SHORE FLOW DRIFTING MOISTURE INLAND WILL
GET SHUT OFF. CONDITIONS WILL NOT STAY UP LONG HOWEVER AS THE FLOW
WILL SWITCH BACK TO ON SHORE ON MONDAY BRINGING ANOTHER ROUND OF
MVFR TO IFR CEILINGS.

LONG TERM...POSSIBLE PERIODS OF MVFR TO IFR MONDAY NIGHT AS
INVERTED TROUGH MOVES INLAND. MVFR LIKELY TO HOLD TUESDAY INTO
TUESDAY NIGHT...LOWERING TO IFR LATE TUESDAY NIGHT INTO THURSDAY
MORNING IN RAIN...WITH INCREASING E-SE WINDS WEDNESDAY.

&&

.MARINE...
SHORT TERM...A FEW WIND GUSTS CONTINUE JUST BELOW 25 KTS THIS
AFTERNOON...WITH WAVES 4` OR LOWER...THEREFORE NO FLAGS IN THE
NEAR TERM. WINDS SHOULD CONTINUE TO SLOWLY DECREASE TONIGHT INTO
TOMORROW FROM THE NORTHEAST.

LONG TERM...HIGH PRESSURE WITH LIGHT AND FAIRLY CALM SEAS WILL
PERSIST THROUGH THE PERIOD AND NO FLAGS ARE EXPECTED.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.

&&

$$
JC



000
FXUS61 KGYX 211427
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
927 AM EST SUN DEC 21 2014

.SYNOPSIS...
HIGH PRESSURE BUILDS OVER NORTHERN MAINE SUNDAY...ALLOWING THE
FLOW TO TURN ONSHORE. A WEAK WEATHER DISTURBANCE MAY TRIGGER SOME
FLURRIES OR LIGHT SNOW OVER SOUTHERN REGIONS RIGHT THROUGH MONDAY.
A SIGNIFICANT LOW PRESSURE SYSTEM SYSTEM WILL GRADUALLY ORGANIZE
WEDNESDAY...BEFORE MOVING OVER THE GREAT LAKES. THIS COULD BRING
WINDY CONDITIONS AND THE POTENTIAL FOR HEAVY RAIN AROUND CHRISTMAS
EVE INTO EARLY CHRISTMAS MORNING.

&&

.NEAR TERM /THROUGH TONIGHT/...
UPDATE...
HAVE UPDATED GRIDS TO RAISE POPS FROM SLIGHT CHANCE/CHANCE TO
CATEGORICAL...AT LEAST FOR THIS MORNING. LOW LEVEL MOISTURE
CONTINUES TO DEPOSIT SNOW ACROSS SOUTHERN NH AND FAR WESTERN
MAINE. WILL FORECAST 1 TO 2 INCHES OF SNOW FOR TODAY AS SOME AREAS
WILL REMAIN NEAR A MILE VSBY IN SNOW. SOME HIGHER REFLECTIVITY
RETURNS IN THE ROCHESTER NH AREA AS WELL WILL PINWHEEL SLOWLY TO
THE NE.

OTHERWISE...JUST MINOR MODIFICATIONS TO THE REST OF THE GRIDED
PACKAGE.

PREV DISC...
615 AM UPDATE...JUST MADE SOME MINOR UPDATES TO SKY
AND TEMPERATURES BASED ON CURRENT OBS AND TRENDS...AS STRATUS
REMAINS ENTRENCHED ACROSS THE REGION.

PREVIOUS DISCUSSION...
LOW STRATUS BLANKETS THE CWFA AS A SURFACE HIGH PRESSURE IN
SOUTHERN QUEBEC IS HELPING TO KEEP MOISTURE TRAPPED IN THE LOW
LEVELS. A WEAK SHORTWAVE THAT IS PASSING OVER THE SOUTHERN NEW
ENGLAND THIS MORNING AND THIS MAY HELP KICK OFF SOME LIGHT SNOW
ACROSS THE FAR SOUTHERN AREAS OF NEW HAMPSHIRE AND PARTS OF
SOUTHWEST MAINE...AS ON SHORE FLOW SUPPLIES THE LOW LEVEL MOISTURE
THE LIFT FROM THIS WEAK SHORT MAY BE JUST ENOUGH TO PRODUCE SNOW
SHOWERS HEAVY ENOUGH TO ACCUMULATE IN SOME AREAS. AS THIS WEAK
WAVE MOVES EAST OUR FLOW...ALTHOUGH VERY WEAK...WILL TURN TO
NORTHWESTERLY AND THIS MAY BE ENOUGH TO START CLEARING OUT SOME OF
THE LOW STRATUS SUNDAY NIGHT.

&&

.SHORT TERM /MONDAY/...
FLOW WILL SWITCH BACK TO ON SHORE BY NOON ON MONDAY AND THIS WILL
BRING LIGHT OCEAN EFFECT SNOW OR MAYBE EVEN SOME LIGHT RAIN OR
EVEN FREEZING DRIZZLE INTO THE INTERIOR AS TEMPERATURES WILL HOVER
CLOSE TO FREEZING AS YOU GET AWAY FROM THE COAST.

&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
MODELS CONTINUE TO TREND TOWARD UPSTREAM AND DOWNSTREAM
BLOCKING...WITH AN EVENTUAL RETURN TO A +PNA PATTERN AT
500MB...WHICH WOULD SIGNAL COOLING LATE IN THE PERIOD. HOWEVER
ALL THE ACTION WILL BE IN DAYS 3 TO 5 AS THE UPSTREAM DEVELOPS AND
SENDS WAVES INTO TROUGH OVER CENTRAL CONUS...AMPLIFYING THE 500
MB FLOW.

INITIALLY...WILL BE DEALING WITH SMALLER SCALE FEATURE AS
INVERTED TROUGH OVER THE GULF OF ME WORK ITS WAY ONSHORE MON NIGHT
AND WEAKENS. MAY BE ENOUGH DYNAMIC FORCING FOR ICE CRYSTALS
INITIALLY...SO RAIN OR SNOW SHOWERS MOVE ONSHORE AND INLAND DURING
THE EVENING...BUT COULD SEE IT TURN TO DZ/FZDZ AS WE WE JUST
TRANSPORT WATER DROPLETS ONSHORE. WE MAINTAIN AN ONSHORE FLOW INTO
TUESDAY...BUT IT LOOKS LIKE FORCING WILL BE LIMITED TO
UPSLOPE...SO THINKING MORE IN THE WAY OF SHSN/SHRA/VERY LIGHT SNOW
INLAND...WITH JUST CLOUDS ON THE COAST. SHOULD SEE TEMPS ON TUE
WARM INTO THE UPPER 30S TO MID 40S.

THE MAIN EVENT REMAINS THE IMPRESSIVE 500 MB TROUGH THAT DEVELOPS
OVER THE CENTRAL CONUS MID WEEK...NOT SO MUCH IN THAT IT IS VERY
DEEP...BUT MORE ITS AMPLITUDE AS IT EXTENDS FROM N OF THE GREAT
LAKES SWD INTO THE GULF OF MEX....AND THEN TILTS VERY NEG AND
LIFTS POLEWARD WED NIGHT AND THU. NOT SURE HOW MUCH AN EFFECT
CONVECTIVE SCALING ISSUES ARE HAVING ON THE MODELS...BUT IT MAY BE
HAVING SOME EFFECT ON THE FORECAST DETAILS...BUT PROB NOT THE
GENERALITIES OF THE FORECAST. HOWEVER...00Z EURO AND GFS BOTH SHOW
A WEAKER SFC LOW IN THE VCNITY OF THE GRT LAKES AND ST LAWRENCE
VLY /ALTHOUGH IT DOES INTENSIFY FURTHER N AND E THAN PREV MODEL
RUNS. STILL...AS THAT WAVE LIFTS NWD WILL SEE TRIPLE POINT DEVELOP
OVER THE MID ATLANTIC WED EVE...AND LIFT NNE INTO THE CWA BY THU
MORNING. THIS WILL CREATE A DEEP SOUTHERLY FLOW WHICH WILL CONNECT
WITH GULF MOISTURE...ALLOWING FOR SIGNIFICANT RAINFALL...FROM
LATE IN THE DAY WED...INTO EARLY THU MORNING. QPF LOOKS TO RUN
AROUND 2-3 INCHES IN MANY SPOTS...BUT S-SE UPSLOPE AREAS OF THE
FOOTHILLS AND MTNS COULD SEE AN INCH OR TWO MORE...SO THE THREAT
OF BOTH FLASH AND MAINSTEM FLOODING IS A CONCERN...ESPECIALLY
SINCE THIS WILL BE COMBINE WITH SIGNIFICANT SNOWMELT AS HIGHS
RISE WELL INTO THE 40S WED..AND WILL LKLY STAY THERE WED NIGHT
INTO THU.

THERE IS STILL THE POTENTIAL FOR SOME STRONG GUSTS...BUT GIVEN
WEAKER SYSTEM...THE WINDOW FOR OPPORTUNITY WILL BE LIMITED TO A
FE HOURS AHEAD OF THE TRIPLE POINT PASSAGE...WHICH LOOKS TO BE WED
EVE...AT LEAST FOR NOW. WITH ALL THAT SAID...WE ARE STILL DEALING
WITH DAYS 4 AND 5 OF THE FORECAST...WITH THE POTENTIAL FRO SOME
DEEP CONVECTION IN THE BASE OF THE TROUGH...SO FORECAST COULD
CHANGE...BUT BOTH EURO AND GFS PICKED UP THE SIGNALS OF THIS
SYSTEM EARLY...AND HAVE BEEN CONSISTENT ON THE WHOLE SO FAR.

CHRISTMAS DAY WILL SEE RAIN ENDING FROM SW TO NE DURING THE
MORNING...WITH SOME PARTIAL CLEARING POSSIBLE IN THE
AFTERNOON...AND TEMPS IN THE 40S AGAIN. COOLER AIR WILL MOVE IN
FROM THE SW THU NIGHT. FRI AND SAT LOOK MOSTLY DRY /OTHER THAN
POSSIBLE UPSLOPE SHSN ON FRI/. HIGHS WILL CONTINUE TO RUN A FEW
DEGREES ABV NORMAL.

&&

.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
SHORT TERM...MVFR TO IFR CEILINGS WILL REMAIN OVER THE REGION
THROUGH AT LEAST SUNDAY EVENING. CONDITIONS MAY IMPROVE A BIT
SUNDAY NIGHT AS THE ON SHORE FLOW DRIFTING MOISTURE INLAND WILL
GET SHUT OFF. CONDITIONS WILL NOT STAY UP LONG HOWEVER AS THE FLOW
WILL SWITCH BACK TO ON SHORE ON MONDAY BRINGING ANOTHER ROUND OF
MVFR TO IFR CEILINGS.

LONG TERM...POSSIBLE PERIODS OF MVFR TO IFR MONDAY NIGHT AS
INVERTED TROUGH MOVES INLAND. MVFR LIKELY TO HOLD TUESDAY INTO
TUESDAY NIGHT...LOWERING TO IFR LATE TUESDAY NIGHT INTO THURSDAY
MORNING IN RAIN...WITH INCREASING E-SE WINDS WEDNESDAY.

&&

.MARINE...
SHORT TERM...A FEW WIND GUSTS CONTINUE JUST BELOW 25 KTS THIS
AFTERNOON...WITH WAVES 4` OR LOWER...THEREFORE NO FLAGS IN THE
NEAR TERM. WINDS SHOULD CONTINUE TO SLOWLY DECREASE TONIGHT INTO
TOMORROW FROM THE NORTHEAST.

LONG TERM...HIGH PRESSURE WITH LIGHT AND FAIRLY CALM SEAS WILL
PERSIST THROUGH THE PERIOD AND NO FLAGS ARE EXPECTED.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.

&&

$$



000
FXUS61 KGYX 211427
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
927 AM EST SUN DEC 21 2014

.SYNOPSIS...
HIGH PRESSURE BUILDS OVER NORTHERN MAINE SUNDAY...ALLOWING THE
FLOW TO TURN ONSHORE. A WEAK WEATHER DISTURBANCE MAY TRIGGER SOME
FLURRIES OR LIGHT SNOW OVER SOUTHERN REGIONS RIGHT THROUGH MONDAY.
A SIGNIFICANT LOW PRESSURE SYSTEM SYSTEM WILL GRADUALLY ORGANIZE
WEDNESDAY...BEFORE MOVING OVER THE GREAT LAKES. THIS COULD BRING
WINDY CONDITIONS AND THE POTENTIAL FOR HEAVY RAIN AROUND CHRISTMAS
EVE INTO EARLY CHRISTMAS MORNING.

&&

.NEAR TERM /THROUGH TONIGHT/...
UPDATE...
HAVE UPDATED GRIDS TO RAISE POPS FROM SLIGHT CHANCE/CHANCE TO
CATEGORICAL...AT LEAST FOR THIS MORNING. LOW LEVEL MOISTURE
CONTINUES TO DEPOSIT SNOW ACROSS SOUTHERN NH AND FAR WESTERN
MAINE. WILL FORECAST 1 TO 2 INCHES OF SNOW FOR TODAY AS SOME AREAS
WILL REMAIN NEAR A MILE VSBY IN SNOW. SOME HIGHER REFLECTIVITY
RETURNS IN THE ROCHESTER NH AREA AS WELL WILL PINWHEEL SLOWLY TO
THE NE.

OTHERWISE...JUST MINOR MODIFICATIONS TO THE REST OF THE GRIDED
PACKAGE.

PREV DISC...
615 AM UPDATE...JUST MADE SOME MINOR UPDATES TO SKY
AND TEMPERATURES BASED ON CURRENT OBS AND TRENDS...AS STRATUS
REMAINS ENTRENCHED ACROSS THE REGION.

PREVIOUS DISCUSSION...
LOW STRATUS BLANKETS THE CWFA AS A SURFACE HIGH PRESSURE IN
SOUTHERN QUEBEC IS HELPING TO KEEP MOISTURE TRAPPED IN THE LOW
LEVELS. A WEAK SHORTWAVE THAT IS PASSING OVER THE SOUTHERN NEW
ENGLAND THIS MORNING AND THIS MAY HELP KICK OFF SOME LIGHT SNOW
ACROSS THE FAR SOUTHERN AREAS OF NEW HAMPSHIRE AND PARTS OF
SOUTHWEST MAINE...AS ON SHORE FLOW SUPPLIES THE LOW LEVEL MOISTURE
THE LIFT FROM THIS WEAK SHORT MAY BE JUST ENOUGH TO PRODUCE SNOW
SHOWERS HEAVY ENOUGH TO ACCUMULATE IN SOME AREAS. AS THIS WEAK
WAVE MOVES EAST OUR FLOW...ALTHOUGH VERY WEAK...WILL TURN TO
NORTHWESTERLY AND THIS MAY BE ENOUGH TO START CLEARING OUT SOME OF
THE LOW STRATUS SUNDAY NIGHT.

&&

.SHORT TERM /MONDAY/...
FLOW WILL SWITCH BACK TO ON SHORE BY NOON ON MONDAY AND THIS WILL
BRING LIGHT OCEAN EFFECT SNOW OR MAYBE EVEN SOME LIGHT RAIN OR
EVEN FREEZING DRIZZLE INTO THE INTERIOR AS TEMPERATURES WILL HOVER
CLOSE TO FREEZING AS YOU GET AWAY FROM THE COAST.

&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
MODELS CONTINUE TO TREND TOWARD UPSTREAM AND DOWNSTREAM
BLOCKING...WITH AN EVENTUAL RETURN TO A +PNA PATTERN AT
500MB...WHICH WOULD SIGNAL COOLING LATE IN THE PERIOD. HOWEVER
ALL THE ACTION WILL BE IN DAYS 3 TO 5 AS THE UPSTREAM DEVELOPS AND
SENDS WAVES INTO TROUGH OVER CENTRAL CONUS...AMPLIFYING THE 500
MB FLOW.

INITIALLY...WILL BE DEALING WITH SMALLER SCALE FEATURE AS
INVERTED TROUGH OVER THE GULF OF ME WORK ITS WAY ONSHORE MON NIGHT
AND WEAKENS. MAY BE ENOUGH DYNAMIC FORCING FOR ICE CRYSTALS
INITIALLY...SO RAIN OR SNOW SHOWERS MOVE ONSHORE AND INLAND DURING
THE EVENING...BUT COULD SEE IT TURN TO DZ/FZDZ AS WE WE JUST
TRANSPORT WATER DROPLETS ONSHORE. WE MAINTAIN AN ONSHORE FLOW INTO
TUESDAY...BUT IT LOOKS LIKE FORCING WILL BE LIMITED TO
UPSLOPE...SO THINKING MORE IN THE WAY OF SHSN/SHRA/VERY LIGHT SNOW
INLAND...WITH JUST CLOUDS ON THE COAST. SHOULD SEE TEMPS ON TUE
WARM INTO THE UPPER 30S TO MID 40S.

THE MAIN EVENT REMAINS THE IMPRESSIVE 500 MB TROUGH THAT DEVELOPS
OVER THE CENTRAL CONUS MID WEEK...NOT SO MUCH IN THAT IT IS VERY
DEEP...BUT MORE ITS AMPLITUDE AS IT EXTENDS FROM N OF THE GREAT
LAKES SWD INTO THE GULF OF MEX....AND THEN TILTS VERY NEG AND
LIFTS POLEWARD WED NIGHT AND THU. NOT SURE HOW MUCH AN EFFECT
CONVECTIVE SCALING ISSUES ARE HAVING ON THE MODELS...BUT IT MAY BE
HAVING SOME EFFECT ON THE FORECAST DETAILS...BUT PROB NOT THE
GENERALITIES OF THE FORECAST. HOWEVER...00Z EURO AND GFS BOTH SHOW
A WEAKER SFC LOW IN THE VCNITY OF THE GRT LAKES AND ST LAWRENCE
VLY /ALTHOUGH IT DOES INTENSIFY FURTHER N AND E THAN PREV MODEL
RUNS. STILL...AS THAT WAVE LIFTS NWD WILL SEE TRIPLE POINT DEVELOP
OVER THE MID ATLANTIC WED EVE...AND LIFT NNE INTO THE CWA BY THU
MORNING. THIS WILL CREATE A DEEP SOUTHERLY FLOW WHICH WILL CONNECT
WITH GULF MOISTURE...ALLOWING FOR SIGNIFICANT RAINFALL...FROM
LATE IN THE DAY WED...INTO EARLY THU MORNING. QPF LOOKS TO RUN
AROUND 2-3 INCHES IN MANY SPOTS...BUT S-SE UPSLOPE AREAS OF THE
FOOTHILLS AND MTNS COULD SEE AN INCH OR TWO MORE...SO THE THREAT
OF BOTH FLASH AND MAINSTEM FLOODING IS A CONCERN...ESPECIALLY
SINCE THIS WILL BE COMBINE WITH SIGNIFICANT SNOWMELT AS HIGHS
RISE WELL INTO THE 40S WED..AND WILL LKLY STAY THERE WED NIGHT
INTO THU.

THERE IS STILL THE POTENTIAL FOR SOME STRONG GUSTS...BUT GIVEN
WEAKER SYSTEM...THE WINDOW FOR OPPORTUNITY WILL BE LIMITED TO A
FE HOURS AHEAD OF THE TRIPLE POINT PASSAGE...WHICH LOOKS TO BE WED
EVE...AT LEAST FOR NOW. WITH ALL THAT SAID...WE ARE STILL DEALING
WITH DAYS 4 AND 5 OF THE FORECAST...WITH THE POTENTIAL FRO SOME
DEEP CONVECTION IN THE BASE OF THE TROUGH...SO FORECAST COULD
CHANGE...BUT BOTH EURO AND GFS PICKED UP THE SIGNALS OF THIS
SYSTEM EARLY...AND HAVE BEEN CONSISTENT ON THE WHOLE SO FAR.

CHRISTMAS DAY WILL SEE RAIN ENDING FROM SW TO NE DURING THE
MORNING...WITH SOME PARTIAL CLEARING POSSIBLE IN THE
AFTERNOON...AND TEMPS IN THE 40S AGAIN. COOLER AIR WILL MOVE IN
FROM THE SW THU NIGHT. FRI AND SAT LOOK MOSTLY DRY /OTHER THAN
POSSIBLE UPSLOPE SHSN ON FRI/. HIGHS WILL CONTINUE TO RUN A FEW
DEGREES ABV NORMAL.

&&

.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
SHORT TERM...MVFR TO IFR CEILINGS WILL REMAIN OVER THE REGION
THROUGH AT LEAST SUNDAY EVENING. CONDITIONS MAY IMPROVE A BIT
SUNDAY NIGHT AS THE ON SHORE FLOW DRIFTING MOISTURE INLAND WILL
GET SHUT OFF. CONDITIONS WILL NOT STAY UP LONG HOWEVER AS THE FLOW
WILL SWITCH BACK TO ON SHORE ON MONDAY BRINGING ANOTHER ROUND OF
MVFR TO IFR CEILINGS.

LONG TERM...POSSIBLE PERIODS OF MVFR TO IFR MONDAY NIGHT AS
INVERTED TROUGH MOVES INLAND. MVFR LIKELY TO HOLD TUESDAY INTO
TUESDAY NIGHT...LOWERING TO IFR LATE TUESDAY NIGHT INTO THURSDAY
MORNING IN RAIN...WITH INCREASING E-SE WINDS WEDNESDAY.

&&

.MARINE...
SHORT TERM...A FEW WIND GUSTS CONTINUE JUST BELOW 25 KTS THIS
AFTERNOON...WITH WAVES 4` OR LOWER...THEREFORE NO FLAGS IN THE
NEAR TERM. WINDS SHOULD CONTINUE TO SLOWLY DECREASE TONIGHT INTO
TOMORROW FROM THE NORTHEAST.

LONG TERM...HIGH PRESSURE WITH LIGHT AND FAIRLY CALM SEAS WILL
PERSIST THROUGH THE PERIOD AND NO FLAGS ARE EXPECTED.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.

&&

$$




000
FXUS61 KBOX 211154
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
654 AM EST SUN DEC 21 2014

.SYNOPSIS...
AN AREA OF SNOW SHOWERS WILL AFFECT AREAS MAINLY SOUTH OF THE MA
TURNPIKE THIS MORNING...EXCEPT IT WILL BE MILD ENOUGH FOR RAIN
SHOWERS ACROSS THE FAR SOUTHEAST NEW ENGLAND COAST. WEAK LOW
PRESSURE WILL PASS SOUTH OF NEW ENGLAND BRINGING ANOTHER PERIOD OF
PRECIPITATION MONDAY NIGHT AND TUESDAY. A MUCH STRONGER STORM
PASSING WEST OF NEW ENGLAND WILL BRING HEAVY RAINFALL...GUSTY
WINDS AND COASTAL FLOODING CONCERNS TO THE REGION WEDNESDAY AND
WEDNESDAY NIGHT. DRY BUT VERY WINDY CONDITIONS FOLLOW FOR
CHRISTMAS DAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...

700 PM UPDATE...

VERY LITTLE CHANGES TO THE FORECAST AS OVERALL TREND IS ON TRACK
FOR THIS MORNING. RADAR ECHOES LOOK A LITTLE DECEIVING AS SNOW HAS
SPREAD ACROSS A GOOD PORTION OF SOUTHERN NEW ENGLAND PER OBS.
ANTICIPATE MORE WIDE SPREAD BUT LIGHT SNOW OVER THE NEXT HOUR OR
TWO OUTSIDE OF THE COASTAL FRONT...WHICH IS DRAPED OVER GHG-TAN-
UUU.

PREVIOUS DISCUSSION...

APPROACHING SHORTWAVE HAS ALLOWED AN AREA LIGHT SNOW SHOWERS TO
EXPAND SOUTH OF THE MA TURNPIKE VERY EARLY THIS MORNING...BUT A FEW
SNOW SHOWERS DID EXTEND INTO NORTHERN MA.  RADAR IMAGERY ACTUALLY
OVER SHOOTING SOME OF THE ACTIVITY ACROSS NORTHERN CT...BASED ON
OBSERVATIONS.  THE RAIN/SNOW LINE RUNS ROUGHLY FROM NEWPORT...TO
TAUNTON AND JUST NORTH OF MARSHFIELD.  OVERALL...DO NOT EXPECT MUCH
CHANGE IN THE RAIN/SNOW LINE THIS MORNING BASED ON THERMAL PROFILES
AND POSITIONING OF THE COASTAL FRONT.

MAIN UNCERTAINTY IS JUST HOW MUCH SNOW OCCURS THIS MORNING WITH THE
SHORTWAVE MOVING ACROSS CT.  GIVEN THE TRACK OF THE SHORTWAVE...BEST
FORCING WILL BE LOCATED SOUTH OF THE MA TURNPIKE AND ESPECIALLY
ACROSS NORTHERN CT/RI.  WE WILL FORECAST 1 TO 2 INCHES OF SNOW
ACROSS THIS REGION...BUT A FEW ISOLATED 3 INCH AMOUNTS CAN NOT BE
RULED OUT. MEANWHILE...AREAS NORTH OF THE MA TURNPIKE WILL BE
REMOVED FROM THE BEST FORCING...BUT STILL SEE SOME SCATTERED
SHOWERS.  ACCUMS IN THIS AREA LIKELY TO BE A DUSTING TO LESS THAN AN
INCH.

ALSO...SOME OF THE PRECIPITATION CURRENTLY ACROSS SOUTHEAST MA IS
BEING ENHANCED FROM THE COASTAL FRONT.  A LOT OF THIS PRECIP WILL
BE IN THE FORM OF RAIN SHOWERS ACROSS PLYMOUTH AND EVEN INTO
PORTIONS OF BRISTOL COUNTY...POINTS SOUTH AND EAST.  HOWEVER...AT
LEAST THE SLIGHTLY HIGHER TERRAIN OF SOUTHEAST MA SHOULD SEE SNOW
SHOWERS.  WILL HAVE TO KEEP A CLOSE EYE ON IF COASTAL FRONT SHIFTS
SLIGHTLY THIS MORNING.  IT COULD MEAN THE DIFFERENCE BETWEEN AN AREA
GETTING MAINLY RAIN SHOWERS OR PERHAPS AN INCH OR SO OF SNOW.
OVERALL...DO NOT EXPECT THE COASTAL FRONT TO MOVE TOO MUCH THIS
MORNING...BUT JUST A FEW MILES CAN MAKE DIFFERENCE FOR A
PARTICULARLY NEIGHBORHOOD.

BULK OF PRECIPITATION WILL BE THIS MORNING WITH THE SHORTWAVE.
HOWEVER...ENOUGH LOW LEVEL MOISTURE/WEAK LIFT WILL REMAIN THIS
AFTERNOON FOR AT LEAST THIS RISK OF SCATTERED PRECIPITATION AND WILL
MAINTAIN SOME POPS.  HIGH TEMPS MAINLY IN THE 30S.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...
TONIGHT...

A RATHER CLOUDY AND RAW NIGHT ACROSS SOUTHERN NEW ENGLAND.  WHILE
THERE IS NOT A SIGNIFICANT SHORTWAVE TO TRIGGER A LOT OF
PRECIPITATION...PLENTY OF LOW LEVEL MOISTURE/WEAK SHALLOW LIFT
REMAINS.  THIS MAY BE ENOUGH TO RESULT IN A FEW RAIN/SNOW SHOWER
FROM TIME TO TIME.  PTYPE...WOULD BE MAINLY SNOW SHOWERS EXCEPT TO
THE SOUTHEAST OF A NEWPORT...TO TAUNTON...TO JUST NORTH OF
MARSHFIELD LINE.  AGAIN...MUCH OF THE NIGHT WILL PROBABLY END UP
DRY...BUT JUST THE RISK FOR A FEW RAIN/SNOW SHOWERS.

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...
HIGHLIGHTS...

* WEAK SHORTWAVE ON MON NIGHT/TUESDAY COULD BRING WINTRY
  MIX/FREEZING RAIN TO THE INTERIOR
* ANOMALOUS SYSTEM ACROSS THE GREAT LAKES WILL BRING HEAVY
  RAIN...GUSTY WINDS AND COASTAL FLOODING CONCERNS AROUND CHRISTMAS
  EVE
* BLUSTERY BUT AIRMASS WILL BE DRYING OUT ON CHRISTMAS DAY

OVERVIEW...

THE MODELS AND ENSEMBLES OFFER A REASONABLY SIMILAR AND PREDICTABLE
LARGER SCALE MID TO UPPER LEVEL PATTERN EVOLUTION FOR MUCH OF THE
UPCOMING WEEK. THIS ACTIVE FLOW REGIME DEVELOPS SEVERAL MID-UPPER
LEVEL TROUGH AND ASSOCIATED/UNSETTLING LEAD SURFACE LOW/FRONTAL
SYSTEMS AND PCPN SWATHS PROGRESS STEADILY ACROSS THE LOWER 48. THE
FIRST AMPLIFIED/DEEP LEAD SYSTEM WORKS ACROSS THE ERN/NERN US INTO
ERN CANADA CHRISTMAS EVE INTO CHRISTMAS ALLOWING FOR A MOIST/WARMED
AIRMASS IN ADVANCE OF FRONTAL APPROACH WITH HEAVIEST LEAD QPF
POTENTIAL OVER NEW ENGLAND. BIGGEST QUESTION IS THE EVOLUTION OF THE
SECONDARY LOW PRESSURE SYSTEM. 00Z GUIDANCE HAS BACKED OFF ON THE
STRENGTH OF THE LOW AND IS HAVING ISSUES ON HOW TO HANDLE ITS
EVOLUTION. THE EC AND GFS HAVE SLOWED DOWN THE SYSTEM SLIGHTLY WITH
THE EC HAVING MORE OF A NEGATIVE TROUGH VS THE GFS. BELIEVE THE
UKMET IS A GOOD COMPROMISE AT IS WAS THE FIRST DETERMINISTIC
GUIDANCE ON TAMPERING DOWN THE FIRST MAIN LOW...WHILE THE CMC IS OUT
TO LUNCH. REGARDLESS THIS IS A VERY ANOMALOUS SYSTEM THAT IS ABOUT 4
STANDARD DEVIATIONS AWAY.

A SECONDARY SYSTEM DEEPENS ACROSS THE FOUR CORNERS ON FRIDAY AND
WITH THE STUBBORN TROUGH OVER THE CENTRAL U.S...IT WILL PUSH A
SYSTEM TOWARDS SOUTHERN NEW ENGLAND BY SUNDAY. THIS SYSTEM MAY
SUPPORT A MODEST SWATH OF OVERRUNNING SNOW OVER SOUTHERN NEW
ENGLAND.

DETAILS...

MONDAY INTO TUESDAY...MODERATE CONFIDENCE.

A WEAK WAVE OF LOW PRESSURE DEVELOPS ALONG THE SOUTHEAST COAST
MONDAY...AND WILL BE ON A DEVELOPING WARM FRONTAL BOUNDARY. THIS LOW
REMAINS WEAK AS THE WARM FRONT MOVES SLOWLY NORTH MONDAY NIGHT INTO
TUESDAY. APPEARS THAT THERE IS DECENT WARM ADVECTION AHEAD OF THIS
WAVE. SEVERAL HI-RES GUIDANCE MODELS SHOW THAT THERE IS THE
POTENTIAL FOR COLD AIR DAMMING ACROSS THE INTERIOR INTO TUESDAY.
BIGGEST QUESTION WILL BE IS THERE ENOUGH MOISTURE FOR PRECIP DURING
THIS TIME FRAME. DUE TO A STRENGTHENING LLJ PROVIDING A GOOD SOURCE OF
LIFT ANTICIPATE PRECIP TO DEVELOP AND OVERSPREAD ACROSS SOUTHERN NEW
ENGLAND. IF THIS PLAYS OUT WITH COLD AIR DAMMING AND WARM AIR
ADVECTION...THEN WE COULD SEE FREEZING RAIN/DRIZZLE ACROSS THE I-91
CORRIDOR LATE MONDAY INTO TUESDAY MORNING. DURING THE DAY ON
TUESDAY...GOOD AMOUNT OF WARM AIR WILL PUSH SURFACE TEMPS ABOVE
FREEZING BY THE LATE MORNING ALLOWING FOR ANY PRECIP TO BE MORE OF
THE LIQUID VARIETY AHEAD OF THE CHRISTMAS EVE STORM. HOWEVER
GUIDANCE IS ALWAYS TOO FAST IN SCOURING TEMPS OUT ESP ACROSS THE CT
VALLEY SO WE WILL NEED TO MONITOR THIS CLOSELY...ESP DUE TO LIGHT
WINDS AND THE HIGH IN EASTERN CANADA. A WINTER WX ADVISORY MAY BE
NEEDED FOR THE LIGHT ICING POTENTIAL.

WE COULD ALSO SEE SOME MINOR COASTAL FLOODING CONCERNS ON TUESDAY. SEE
BELOW FOR MORE DETAILS.

WEDNESDAY INTO THURSDAY...HIGH CONFIDENCE IN SYSTEM LOW CONFIDENCE
ON DETAILS.

ANOMALOUS SYSTEM WILL STRENGTHEN OVER THE GREAT LAKES TUESDAY INTO
WEDNESDAY. A SECONDARY SHORTWAVE WILL ROUND THE DEEP TROUGH AND
DEVELOP A SECONDARY LOW PRESSURE ALONG THE COLD FRONT. THIS
SECONDARY LOW WILL STRENGTHEN AND PASS WEST OF SOUTHERN NEW ENGLAND.
THIS SYSTEM WILL CONTINUE TO DEEPEN AS IT MOVES TOWARDS EASTERN
CANADA SWINGING A COLD FRONT ACROSS THE NORTHEAST.

STRONG SOUTHERLY JET OUT AHEAD OF THE FRONT WITH A GULF MOISTURE
CONNECTION WILL IMPACT SOUTHERN NEW ENGLAND ON CHRISTMAS EVE. THIS
STRONG JET WILL YIELD FOR PCPN IN THE LIQUID VARIETY.  PW ANOMALIES
ARE BETWEEN +4 TO +5 STANDARD DEVIATIONS ABOVE NORMAL WHICH IS QUITE
ANOMALOUS FOR THIS TIME OF YEAR. IN FACT CURRENT PWATS ARE PROGGED
ABOVE 1.6 INCHES WITH MODEL QPF OVER 2 INCHES...AT THE VERY LEAST
COULD SEE URBAN AND POOR DRAINAGE FLOODING. LATEST EC EVEN SHOWS
OVER 2.5 INCHES OF QPF...AND WITH THE TROPICAL CONNECTION AND STRONG
SOUTHERLY FLOW COULD SEE HIGHER AMOUNTS DUE TO TOPOGRAPHY
ENHANCEMENTS. RAINFALL RECORDS MAY FALL IF EVERYTHING FALLS INTO
PLACE.

AHEAD OF THE FRONT...SOUTHERN NEW ENGLAND WILL WARM SECTOR WED INTO
THUR MORNING ALLOWING FOR TEMPERATURES TO BE WELL ABOVE AVERAGE. IN
FACT WE MAY BE CLOSE AT BREAKING RECORD HIGH TEMPS IF TEMPS WARM TO
60F OR ABOVE ON CHRISTMAS EVE. SINCE WE WILL BE IN THE WARM
SECTOR...AND SHOWALTERS CLOSE TO ZERO...ISOLATED THUNDER IS STILL
POSSIBLE.

STRONG LOW LEVEL WINDS WILL ALSO BE A CONCERN ESPECIALLY WEDNESDAY
NIGHT. THE ECMWF SHOWS EAST-SOUTHEAST WINDS 30-40 KNOTS ON WEDNESDAY
INCREASING TO 60-75 KNOTS BY WEDNESDAY NIGHT. STRONG DOWNPOURS MAY
OVERCOME THE LOW LEVEL INVERSION AND BRING STRONG GUSTS OF AT LEAST
30-40 KNOTS ESPECIALLY ALONG THE SOUTH COAST. A WIND ADVISORY MAY BE
NEEDED IN SOME AREAS.

CHRISTMAS DAY...MODERATE CONFIDENCE.

AS THE COLD FRONT PASSES THROUGH EARLY CHRISTMAS DAY...THE WEST
WINDS WILL HELP DRY THE AIRMASS ALLOWING FOR PARTLY SUNNY SKIES.
STRONG CAA ON THURSDAY WILL ALLOW DESCENT MIXING. WINDS IN THE SFC-
850 MB LAYER WILL BE 30-40 KNOTS AND POSSIBLY A LITTLE
HIGHER...WHICH WOULD REQUIRE A WIND ADVISORY FOR MUCH OF THE AREA.

FRIDAY-SUNDAY...LOWER CONFIDENCE

WEAK HIGH PRESSURE BUILDS OVER THE AREA FRIDAY INTO SATURDAY. THE
NEXT SHORTWAVE APPROACHES LATE SATURDAY INTO SUNDAY AND SHOULD BRING
INCREASING CLOUDS FROM WEST TO EAST ALONG WITH A CHANCE OF RAIN OR
SNOW SHOWERS MAINLY IN THE AFTERNOON AND AT NIGHT.

&&

.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /TODAY AND TONIGHT/...

TODAY AND TONIGHT...MODERATE CONFIDENCE.  MAINLY MVFR CONDITIONS
SOUTH OF THE MA TURNPIKE WITH BORDERLINE VFR TO MARGINAL MVFR CIGS
NORTH OF THE PIKE THROUGH TONIGHT.  AN AREA OF SNOW SHOWERS WILL
EXPAND MAINLY ACROSS AREAS SOUTH OF THE PIKE THIS MORNING...BUT A
FEW SNOW SHOWERS WILL STILL AFFECT NORTHERN MA.  VSBYS/CIGS MAY
BRIEFLY DROP TO IFR LEVELS IN NORTHERN CT/RI/SE MA.  PTYPE WILL BE
RAIN SHOWERS ACROSS MOST OF PLYMOUTH COUNTY AND ONTO THE
CAPE/ISLANDS WITH SNOW SHOWERS NORTH AND WEST.  BULK OF PRECIP THIS
MORNING...BUT A FEW LINGERING RAIN/SNOW SHOWERS STILL POSSIBLE THIS
AFTERNOON AND EVENING.

KBOS TERMINAL...MODERATE CONFIDENCE.  A FEW SNOW SHOWERS POSSIBLE
THIS MORNING BUT BULK OF ACTIVITY SHOULD BE SOUTH OF THE TERMINAL.

KBDL TERMINAL...MODERATE CONFIDENCE.  PERIOD OF SNOW SHOWERS THIS
MORNING MAY DROP AN INCH OR TWO OF SNOW.  MVFR CONDITIONS DOMINATE
TODAY....BUT A BRIEF PERIOD OF IFR CONDITIONS ARE POSSIBLE THIS
MORNING IN SNOW SHOWERS.

OUTLOOK...MONDAY THROUGH THURSDAY...MODERATE CONFIDENCE.

MONDAY...MVFR CIGS CONTINUE IN RI/EASTERN MASS IN MARINE EAST FLOW.
VFR IN THE WEST.

TUESDAY...VFR WITH SCATTERED MVFR IN ANY RAIN/SNOW SHOWERS.

WEDNESDAY...CONDITIONS LOWERING TO IFR IN RAIN/HEAVY RAIN. ISOLATED
THUNDERSTORMS POSSIBLE ESPECIALLY WEDNESDAY NIGHT. EAST-SOUTHEAST
SURFACE WINDS MAY GUST TO 35-45 KNOTS. WINDS AT 2000 FEET AGL WILL
REACH 50-60 KNOTS WEDNESDAY AFTERNOON AND EARLY NIGHT CREATING LOW
LEVEL WIND SHEAR CONCERNS.

CHRISTMAS DAY...WEST WIND GUSTING 30-40 KNOTS. CONDITIONS IMPROVING
TO VFR AS THE WIND BRINGS IN COOLER DRIER AIR.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /TODAY AND TONIGHT/...HIGH CONFIDENCE.

HIGH PRESSURE ACROSS QUEBEC WILL RESULT IN NORTHEAST WINDS ACROSS
THE WATERS THAT WILL GUST TO BETWEEN 15 AND 20 KNOTS.  THIS WILL
RESULT IN 2 TO 4 FOOT SEAS.  HOWEVER...NO HEADLINES PLANNED AS
CONDITIONS SHOULD REMAIN BELOW SMALL CRAFT ADVISORY THRESHOLDS.

OUTLOOK...MONDAY THROUGH THURSDAY...MODERATE CONFIDENCE

MONDAY...EAST TO NORTHEAST WINDS GUSTING AROUND 15 KNOTS OR LESS.
SEAS WILL HOLD AROUND 3-4 FEET...MAY INCREASE TO 5FT IN NORTHEAST
FLOW AS GUIDANCE MAY BE UNDERDONE.

TUESDAY... INCREASING EAST WINDS WITH FREQUENT GUSTS 25 TO 30 KNOTS.
SEAS WILL BUILD TO 5-6 FEET ON THE EXPOSED WATERS.  A SMALL CRAFT
ADVISORY MAY BE NEEDED.

WEDNESDAY...RAIN WILL BE HEAVY AT TIMES PRODUCING POOR VISIBILITY.
INCREASING SOUTHEAST WINDS 20-25 SUSTAINED AND 40 KNOT GUSTS.  WINDS
SHOULD SHIFT TO SOUTH WEDNESDAY NIGHT AND SOUTHWEST TOWARD THURSDAY
MORNING. RAIN WILL TAPER OFF WITH THE WIND SHIFT TO SOUTHWEST. SEAS
WILL CONTINUE TO BUILD WITH 7-11 FEET HEIGHTS ON THE EXPOSED WATERS.
A GALE WARNING WILL BE NEEDED...WITH A LOW PROB OF A FEW STORM FORCE
GUSTS ACROSS THE EASTERN OUTER WATERS.

CHRISTMAS DAY... WEST SOUTHWEST WINDS WILL CONTINUE TO GUST 35-40
KNOTS...SO A CONTINUED GALE WARNING MAY BE NEEDED. SEAS OF 7-15 FEET
ARE POSSIBLE ON THE EXPOSED WATERS...AND 5 FEET IS POSSIBLE ON SOME
OF THE NEARSHORE WATERS.

&&

.TIDES/COASTAL FLOODING...
HIGH ASTRONOMICAL TIDES WILL OCCUR TUESDAY THROUGH THURSDAY. BREAKING
IT DOWN...ON TUESDAY HIGH TIDE AT BOSTON WILL BE 11.6 FT. THERE WILL
BE ONSHORE FLOW DURING THIS HIGH TIDE ALLOWING FOR MINOR SPLASHOVER.
IF WIND GUSTS INCREASE THEN COULD POSSIBLE SEE MINOR COASTAL
FLOODING.

ON WEDNESDAY...WINDS WILL SWITCH TO A MORE SOUTHEASTERLY FLOW DURING
THE DAY AND INCREASE QUICKLY FROM APPROACHING SYSTEM AND DECENT
PRESSURE FALLS. WEDNESDAY AFTERNOON HIGH TIDE IN BOSTON IS 11.7 FT
AND WITH ANY STRENGTH ON THE EASTERLY WIND FLOW WILL PUSH THE TIDE
OVER. RIGHT NOW BELIEVE MINOR COASTAL FLOODING IS POSSIBLE ALONG THE
EAST COASTLINE.

WEDNESDAY EVENING...THE WIND GOES IN A MORE SOUTHERLY DIRECTION AND
THE TIDE WILL BE INCREASE ACROSS THE SOUTH COAST. HIGH TIDE IN
PROVIDENCE WILL BE 5.2 FT. 925 MB LLJ STRENGTHENS TO 50-60 KTS WHICH
COULD PUSH A DECENT SURGE UP ALONG THE SOUTH COAST DURING THE TIME
OF HIGH TIDE. THINKING THAT MINOR COASTAL FLOODING COULD OCCUR BUT
CANNOT RULE OUT MODERATE ALONG THE SOUTH COAST...ESP IF LLJ
STRENGTHENS EVEN MORE.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...FRANK/DUNTEN
NEAR TERM...FRANK/DUNTEN
SHORT TERM...FRANK
LONG TERM...DUNTEN
AVIATION...FRANK/DUNTEN
MARINE...FRANK/DUNTEN
TIDES/COASTAL FLOODING...STAFF




000
FXUS61 KBOX 211154
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
654 AM EST SUN DEC 21 2014

.SYNOPSIS...
AN AREA OF SNOW SHOWERS WILL AFFECT AREAS MAINLY SOUTH OF THE MA
TURNPIKE THIS MORNING...EXCEPT IT WILL BE MILD ENOUGH FOR RAIN
SHOWERS ACROSS THE FAR SOUTHEAST NEW ENGLAND COAST. WEAK LOW
PRESSURE WILL PASS SOUTH OF NEW ENGLAND BRINGING ANOTHER PERIOD OF
PRECIPITATION MONDAY NIGHT AND TUESDAY. A MUCH STRONGER STORM
PASSING WEST OF NEW ENGLAND WILL BRING HEAVY RAINFALL...GUSTY
WINDS AND COASTAL FLOODING CONCERNS TO THE REGION WEDNESDAY AND
WEDNESDAY NIGHT. DRY BUT VERY WINDY CONDITIONS FOLLOW FOR
CHRISTMAS DAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...

700 PM UPDATE...

VERY LITTLE CHANGES TO THE FORECAST AS OVERALL TREND IS ON TRACK
FOR THIS MORNING. RADAR ECHOES LOOK A LITTLE DECEIVING AS SNOW HAS
SPREAD ACROSS A GOOD PORTION OF SOUTHERN NEW ENGLAND PER OBS.
ANTICIPATE MORE WIDE SPREAD BUT LIGHT SNOW OVER THE NEXT HOUR OR
TWO OUTSIDE OF THE COASTAL FRONT...WHICH IS DRAPED OVER GHG-TAN-
UUU.

PREVIOUS DISCUSSION...

APPROACHING SHORTWAVE HAS ALLOWED AN AREA LIGHT SNOW SHOWERS TO
EXPAND SOUTH OF THE MA TURNPIKE VERY EARLY THIS MORNING...BUT A FEW
SNOW SHOWERS DID EXTEND INTO NORTHERN MA.  RADAR IMAGERY ACTUALLY
OVER SHOOTING SOME OF THE ACTIVITY ACROSS NORTHERN CT...BASED ON
OBSERVATIONS.  THE RAIN/SNOW LINE RUNS ROUGHLY FROM NEWPORT...TO
TAUNTON AND JUST NORTH OF MARSHFIELD.  OVERALL...DO NOT EXPECT MUCH
CHANGE IN THE RAIN/SNOW LINE THIS MORNING BASED ON THERMAL PROFILES
AND POSITIONING OF THE COASTAL FRONT.

MAIN UNCERTAINTY IS JUST HOW MUCH SNOW OCCURS THIS MORNING WITH THE
SHORTWAVE MOVING ACROSS CT.  GIVEN THE TRACK OF THE SHORTWAVE...BEST
FORCING WILL BE LOCATED SOUTH OF THE MA TURNPIKE AND ESPECIALLY
ACROSS NORTHERN CT/RI.  WE WILL FORECAST 1 TO 2 INCHES OF SNOW
ACROSS THIS REGION...BUT A FEW ISOLATED 3 INCH AMOUNTS CAN NOT BE
RULED OUT. MEANWHILE...AREAS NORTH OF THE MA TURNPIKE WILL BE
REMOVED FROM THE BEST FORCING...BUT STILL SEE SOME SCATTERED
SHOWERS.  ACCUMS IN THIS AREA LIKELY TO BE A DUSTING TO LESS THAN AN
INCH.

ALSO...SOME OF THE PRECIPITATION CURRENTLY ACROSS SOUTHEAST MA IS
BEING ENHANCED FROM THE COASTAL FRONT.  A LOT OF THIS PRECIP WILL
BE IN THE FORM OF RAIN SHOWERS ACROSS PLYMOUTH AND EVEN INTO
PORTIONS OF BRISTOL COUNTY...POINTS SOUTH AND EAST.  HOWEVER...AT
LEAST THE SLIGHTLY HIGHER TERRAIN OF SOUTHEAST MA SHOULD SEE SNOW
SHOWERS.  WILL HAVE TO KEEP A CLOSE EYE ON IF COASTAL FRONT SHIFTS
SLIGHTLY THIS MORNING.  IT COULD MEAN THE DIFFERENCE BETWEEN AN AREA
GETTING MAINLY RAIN SHOWERS OR PERHAPS AN INCH OR SO OF SNOW.
OVERALL...DO NOT EXPECT THE COASTAL FRONT TO MOVE TOO MUCH THIS
MORNING...BUT JUST A FEW MILES CAN MAKE DIFFERENCE FOR A
PARTICULARLY NEIGHBORHOOD.

BULK OF PRECIPITATION WILL BE THIS MORNING WITH THE SHORTWAVE.
HOWEVER...ENOUGH LOW LEVEL MOISTURE/WEAK LIFT WILL REMAIN THIS
AFTERNOON FOR AT LEAST THIS RISK OF SCATTERED PRECIPITATION AND WILL
MAINTAIN SOME POPS.  HIGH TEMPS MAINLY IN THE 30S.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...
TONIGHT...

A RATHER CLOUDY AND RAW NIGHT ACROSS SOUTHERN NEW ENGLAND.  WHILE
THERE IS NOT A SIGNIFICANT SHORTWAVE TO TRIGGER A LOT OF
PRECIPITATION...PLENTY OF LOW LEVEL MOISTURE/WEAK SHALLOW LIFT
REMAINS.  THIS MAY BE ENOUGH TO RESULT IN A FEW RAIN/SNOW SHOWER
FROM TIME TO TIME.  PTYPE...WOULD BE MAINLY SNOW SHOWERS EXCEPT TO
THE SOUTHEAST OF A NEWPORT...TO TAUNTON...TO JUST NORTH OF
MARSHFIELD LINE.  AGAIN...MUCH OF THE NIGHT WILL PROBABLY END UP
DRY...BUT JUST THE RISK FOR A FEW RAIN/SNOW SHOWERS.

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...
HIGHLIGHTS...

* WEAK SHORTWAVE ON MON NIGHT/TUESDAY COULD BRING WINTRY
  MIX/FREEZING RAIN TO THE INTERIOR
* ANOMALOUS SYSTEM ACROSS THE GREAT LAKES WILL BRING HEAVY
  RAIN...GUSTY WINDS AND COASTAL FLOODING CONCERNS AROUND CHRISTMAS
  EVE
* BLUSTERY BUT AIRMASS WILL BE DRYING OUT ON CHRISTMAS DAY

OVERVIEW...

THE MODELS AND ENSEMBLES OFFER A REASONABLY SIMILAR AND PREDICTABLE
LARGER SCALE MID TO UPPER LEVEL PATTERN EVOLUTION FOR MUCH OF THE
UPCOMING WEEK. THIS ACTIVE FLOW REGIME DEVELOPS SEVERAL MID-UPPER
LEVEL TROUGH AND ASSOCIATED/UNSETTLING LEAD SURFACE LOW/FRONTAL
SYSTEMS AND PCPN SWATHS PROGRESS STEADILY ACROSS THE LOWER 48. THE
FIRST AMPLIFIED/DEEP LEAD SYSTEM WORKS ACROSS THE ERN/NERN US INTO
ERN CANADA CHRISTMAS EVE INTO CHRISTMAS ALLOWING FOR A MOIST/WARMED
AIRMASS IN ADVANCE OF FRONTAL APPROACH WITH HEAVIEST LEAD QPF
POTENTIAL OVER NEW ENGLAND. BIGGEST QUESTION IS THE EVOLUTION OF THE
SECONDARY LOW PRESSURE SYSTEM. 00Z GUIDANCE HAS BACKED OFF ON THE
STRENGTH OF THE LOW AND IS HAVING ISSUES ON HOW TO HANDLE ITS
EVOLUTION. THE EC AND GFS HAVE SLOWED DOWN THE SYSTEM SLIGHTLY WITH
THE EC HAVING MORE OF A NEGATIVE TROUGH VS THE GFS. BELIEVE THE
UKMET IS A GOOD COMPROMISE AT IS WAS THE FIRST DETERMINISTIC
GUIDANCE ON TAMPERING DOWN THE FIRST MAIN LOW...WHILE THE CMC IS OUT
TO LUNCH. REGARDLESS THIS IS A VERY ANOMALOUS SYSTEM THAT IS ABOUT 4
STANDARD DEVIATIONS AWAY.

A SECONDARY SYSTEM DEEPENS ACROSS THE FOUR CORNERS ON FRIDAY AND
WITH THE STUBBORN TROUGH OVER THE CENTRAL U.S...IT WILL PUSH A
SYSTEM TOWARDS SOUTHERN NEW ENGLAND BY SUNDAY. THIS SYSTEM MAY
SUPPORT A MODEST SWATH OF OVERRUNNING SNOW OVER SOUTHERN NEW
ENGLAND.

DETAILS...

MONDAY INTO TUESDAY...MODERATE CONFIDENCE.

A WEAK WAVE OF LOW PRESSURE DEVELOPS ALONG THE SOUTHEAST COAST
MONDAY...AND WILL BE ON A DEVELOPING WARM FRONTAL BOUNDARY. THIS LOW
REMAINS WEAK AS THE WARM FRONT MOVES SLOWLY NORTH MONDAY NIGHT INTO
TUESDAY. APPEARS THAT THERE IS DECENT WARM ADVECTION AHEAD OF THIS
WAVE. SEVERAL HI-RES GUIDANCE MODELS SHOW THAT THERE IS THE
POTENTIAL FOR COLD AIR DAMMING ACROSS THE INTERIOR INTO TUESDAY.
BIGGEST QUESTION WILL BE IS THERE ENOUGH MOISTURE FOR PRECIP DURING
THIS TIME FRAME. DUE TO A STRENGTHENING LLJ PROVIDING A GOOD SOURCE OF
LIFT ANTICIPATE PRECIP TO DEVELOP AND OVERSPREAD ACROSS SOUTHERN NEW
ENGLAND. IF THIS PLAYS OUT WITH COLD AIR DAMMING AND WARM AIR
ADVECTION...THEN WE COULD SEE FREEZING RAIN/DRIZZLE ACROSS THE I-91
CORRIDOR LATE MONDAY INTO TUESDAY MORNING. DURING THE DAY ON
TUESDAY...GOOD AMOUNT OF WARM AIR WILL PUSH SURFACE TEMPS ABOVE
FREEZING BY THE LATE MORNING ALLOWING FOR ANY PRECIP TO BE MORE OF
THE LIQUID VARIETY AHEAD OF THE CHRISTMAS EVE STORM. HOWEVER
GUIDANCE IS ALWAYS TOO FAST IN SCOURING TEMPS OUT ESP ACROSS THE CT
VALLEY SO WE WILL NEED TO MONITOR THIS CLOSELY...ESP DUE TO LIGHT
WINDS AND THE HIGH IN EASTERN CANADA. A WINTER WX ADVISORY MAY BE
NEEDED FOR THE LIGHT ICING POTENTIAL.

WE COULD ALSO SEE SOME MINOR COASTAL FLOODING CONCERNS ON TUESDAY. SEE
BELOW FOR MORE DETAILS.

WEDNESDAY INTO THURSDAY...HIGH CONFIDENCE IN SYSTEM LOW CONFIDENCE
ON DETAILS.

ANOMALOUS SYSTEM WILL STRENGTHEN OVER THE GREAT LAKES TUESDAY INTO
WEDNESDAY. A SECONDARY SHORTWAVE WILL ROUND THE DEEP TROUGH AND
DEVELOP A SECONDARY LOW PRESSURE ALONG THE COLD FRONT. THIS
SECONDARY LOW WILL STRENGTHEN AND PASS WEST OF SOUTHERN NEW ENGLAND.
THIS SYSTEM WILL CONTINUE TO DEEPEN AS IT MOVES TOWARDS EASTERN
CANADA SWINGING A COLD FRONT ACROSS THE NORTHEAST.

STRONG SOUTHERLY JET OUT AHEAD OF THE FRONT WITH A GULF MOISTURE
CONNECTION WILL IMPACT SOUTHERN NEW ENGLAND ON CHRISTMAS EVE. THIS
STRONG JET WILL YIELD FOR PCPN IN THE LIQUID VARIETY.  PW ANOMALIES
ARE BETWEEN +4 TO +5 STANDARD DEVIATIONS ABOVE NORMAL WHICH IS QUITE
ANOMALOUS FOR THIS TIME OF YEAR. IN FACT CURRENT PWATS ARE PROGGED
ABOVE 1.6 INCHES WITH MODEL QPF OVER 2 INCHES...AT THE VERY LEAST
COULD SEE URBAN AND POOR DRAINAGE FLOODING. LATEST EC EVEN SHOWS
OVER 2.5 INCHES OF QPF...AND WITH THE TROPICAL CONNECTION AND STRONG
SOUTHERLY FLOW COULD SEE HIGHER AMOUNTS DUE TO TOPOGRAPHY
ENHANCEMENTS. RAINFALL RECORDS MAY FALL IF EVERYTHING FALLS INTO
PLACE.

AHEAD OF THE FRONT...SOUTHERN NEW ENGLAND WILL WARM SECTOR WED INTO
THUR MORNING ALLOWING FOR TEMPERATURES TO BE WELL ABOVE AVERAGE. IN
FACT WE MAY BE CLOSE AT BREAKING RECORD HIGH TEMPS IF TEMPS WARM TO
60F OR ABOVE ON CHRISTMAS EVE. SINCE WE WILL BE IN THE WARM
SECTOR...AND SHOWALTERS CLOSE TO ZERO...ISOLATED THUNDER IS STILL
POSSIBLE.

STRONG LOW LEVEL WINDS WILL ALSO BE A CONCERN ESPECIALLY WEDNESDAY
NIGHT. THE ECMWF SHOWS EAST-SOUTHEAST WINDS 30-40 KNOTS ON WEDNESDAY
INCREASING TO 60-75 KNOTS BY WEDNESDAY NIGHT. STRONG DOWNPOURS MAY
OVERCOME THE LOW LEVEL INVERSION AND BRING STRONG GUSTS OF AT LEAST
30-40 KNOTS ESPECIALLY ALONG THE SOUTH COAST. A WIND ADVISORY MAY BE
NEEDED IN SOME AREAS.

CHRISTMAS DAY...MODERATE CONFIDENCE.

AS THE COLD FRONT PASSES THROUGH EARLY CHRISTMAS DAY...THE WEST
WINDS WILL HELP DRY THE AIRMASS ALLOWING FOR PARTLY SUNNY SKIES.
STRONG CAA ON THURSDAY WILL ALLOW DESCENT MIXING. WINDS IN THE SFC-
850 MB LAYER WILL BE 30-40 KNOTS AND POSSIBLY A LITTLE
HIGHER...WHICH WOULD REQUIRE A WIND ADVISORY FOR MUCH OF THE AREA.

FRIDAY-SUNDAY...LOWER CONFIDENCE

WEAK HIGH PRESSURE BUILDS OVER THE AREA FRIDAY INTO SATURDAY. THE
NEXT SHORTWAVE APPROACHES LATE SATURDAY INTO SUNDAY AND SHOULD BRING
INCREASING CLOUDS FROM WEST TO EAST ALONG WITH A CHANCE OF RAIN OR
SNOW SHOWERS MAINLY IN THE AFTERNOON AND AT NIGHT.

&&

.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /TODAY AND TONIGHT/...

TODAY AND TONIGHT...MODERATE CONFIDENCE.  MAINLY MVFR CONDITIONS
SOUTH OF THE MA TURNPIKE WITH BORDERLINE VFR TO MARGINAL MVFR CIGS
NORTH OF THE PIKE THROUGH TONIGHT.  AN AREA OF SNOW SHOWERS WILL
EXPAND MAINLY ACROSS AREAS SOUTH OF THE PIKE THIS MORNING...BUT A
FEW SNOW SHOWERS WILL STILL AFFECT NORTHERN MA.  VSBYS/CIGS MAY
BRIEFLY DROP TO IFR LEVELS IN NORTHERN CT/RI/SE MA.  PTYPE WILL BE
RAIN SHOWERS ACROSS MOST OF PLYMOUTH COUNTY AND ONTO THE
CAPE/ISLANDS WITH SNOW SHOWERS NORTH AND WEST.  BULK OF PRECIP THIS
MORNING...BUT A FEW LINGERING RAIN/SNOW SHOWERS STILL POSSIBLE THIS
AFTERNOON AND EVENING.

KBOS TERMINAL...MODERATE CONFIDENCE.  A FEW SNOW SHOWERS POSSIBLE
THIS MORNING BUT BULK OF ACTIVITY SHOULD BE SOUTH OF THE TERMINAL.

KBDL TERMINAL...MODERATE CONFIDENCE.  PERIOD OF SNOW SHOWERS THIS
MORNING MAY DROP AN INCH OR TWO OF SNOW.  MVFR CONDITIONS DOMINATE
TODAY....BUT A BRIEF PERIOD OF IFR CONDITIONS ARE POSSIBLE THIS
MORNING IN SNOW SHOWERS.

OUTLOOK...MONDAY THROUGH THURSDAY...MODERATE CONFIDENCE.

MONDAY...MVFR CIGS CONTINUE IN RI/EASTERN MASS IN MARINE EAST FLOW.
VFR IN THE WEST.

TUESDAY...VFR WITH SCATTERED MVFR IN ANY RAIN/SNOW SHOWERS.

WEDNESDAY...CONDITIONS LOWERING TO IFR IN RAIN/HEAVY RAIN. ISOLATED
THUNDERSTORMS POSSIBLE ESPECIALLY WEDNESDAY NIGHT. EAST-SOUTHEAST
SURFACE WINDS MAY GUST TO 35-45 KNOTS. WINDS AT 2000 FEET AGL WILL
REACH 50-60 KNOTS WEDNESDAY AFTERNOON AND EARLY NIGHT CREATING LOW
LEVEL WIND SHEAR CONCERNS.

CHRISTMAS DAY...WEST WIND GUSTING 30-40 KNOTS. CONDITIONS IMPROVING
TO VFR AS THE WIND BRINGS IN COOLER DRIER AIR.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /TODAY AND TONIGHT/...HIGH CONFIDENCE.

HIGH PRESSURE ACROSS QUEBEC WILL RESULT IN NORTHEAST WINDS ACROSS
THE WATERS THAT WILL GUST TO BETWEEN 15 AND 20 KNOTS.  THIS WILL
RESULT IN 2 TO 4 FOOT SEAS.  HOWEVER...NO HEADLINES PLANNED AS
CONDITIONS SHOULD REMAIN BELOW SMALL CRAFT ADVISORY THRESHOLDS.

OUTLOOK...MONDAY THROUGH THURSDAY...MODERATE CONFIDENCE

MONDAY...EAST TO NORTHEAST WINDS GUSTING AROUND 15 KNOTS OR LESS.
SEAS WILL HOLD AROUND 3-4 FEET...MAY INCREASE TO 5FT IN NORTHEAST
FLOW AS GUIDANCE MAY BE UNDERDONE.

TUESDAY... INCREASING EAST WINDS WITH FREQUENT GUSTS 25 TO 30 KNOTS.
SEAS WILL BUILD TO 5-6 FEET ON THE EXPOSED WATERS.  A SMALL CRAFT
ADVISORY MAY BE NEEDED.

WEDNESDAY...RAIN WILL BE HEAVY AT TIMES PRODUCING POOR VISIBILITY.
INCREASING SOUTHEAST WINDS 20-25 SUSTAINED AND 40 KNOT GUSTS.  WINDS
SHOULD SHIFT TO SOUTH WEDNESDAY NIGHT AND SOUTHWEST TOWARD THURSDAY
MORNING. RAIN WILL TAPER OFF WITH THE WIND SHIFT TO SOUTHWEST. SEAS
WILL CONTINUE TO BUILD WITH 7-11 FEET HEIGHTS ON THE EXPOSED WATERS.
A GALE WARNING WILL BE NEEDED...WITH A LOW PROB OF A FEW STORM FORCE
GUSTS ACROSS THE EASTERN OUTER WATERS.

CHRISTMAS DAY... WEST SOUTHWEST WINDS WILL CONTINUE TO GUST 35-40
KNOTS...SO A CONTINUED GALE WARNING MAY BE NEEDED. SEAS OF 7-15 FEET
ARE POSSIBLE ON THE EXPOSED WATERS...AND 5 FEET IS POSSIBLE ON SOME
OF THE NEARSHORE WATERS.

&&

.TIDES/COASTAL FLOODING...
HIGH ASTRONOMICAL TIDES WILL OCCUR TUESDAY THROUGH THURSDAY. BREAKING
IT DOWN...ON TUESDAY HIGH TIDE AT BOSTON WILL BE 11.6 FT. THERE WILL
BE ONSHORE FLOW DURING THIS HIGH TIDE ALLOWING FOR MINOR SPLASHOVER.
IF WIND GUSTS INCREASE THEN COULD POSSIBLE SEE MINOR COASTAL
FLOODING.

ON WEDNESDAY...WINDS WILL SWITCH TO A MORE SOUTHEASTERLY FLOW DURING
THE DAY AND INCREASE QUICKLY FROM APPROACHING SYSTEM AND DECENT
PRESSURE FALLS. WEDNESDAY AFTERNOON HIGH TIDE IN BOSTON IS 11.7 FT
AND WITH ANY STRENGTH ON THE EASTERLY WIND FLOW WILL PUSH THE TIDE
OVER. RIGHT NOW BELIEVE MINOR COASTAL FLOODING IS POSSIBLE ALONG THE
EAST COASTLINE.

WEDNESDAY EVENING...THE WIND GOES IN A MORE SOUTHERLY DIRECTION AND
THE TIDE WILL BE INCREASE ACROSS THE SOUTH COAST. HIGH TIDE IN
PROVIDENCE WILL BE 5.2 FT. 925 MB LLJ STRENGTHENS TO 50-60 KTS WHICH
COULD PUSH A DECENT SURGE UP ALONG THE SOUTH COAST DURING THE TIME
OF HIGH TIDE. THINKING THAT MINOR COASTAL FLOODING COULD OCCUR BUT
CANNOT RULE OUT MODERATE ALONG THE SOUTH COAST...ESP IF LLJ
STRENGTHENS EVEN MORE.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...FRANK/DUNTEN
NEAR TERM...FRANK/DUNTEN
SHORT TERM...FRANK
LONG TERM...DUNTEN
AVIATION...FRANK/DUNTEN
MARINE...FRANK/DUNTEN
TIDES/COASTAL FLOODING...STAFF




000
FXUS61 KBOX 211154
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
654 AM EST SUN DEC 21 2014

.SYNOPSIS...
AN AREA OF SNOW SHOWERS WILL AFFECT AREAS MAINLY SOUTH OF THE MA
TURNPIKE THIS MORNING...EXCEPT IT WILL BE MILD ENOUGH FOR RAIN
SHOWERS ACROSS THE FAR SOUTHEAST NEW ENGLAND COAST. WEAK LOW
PRESSURE WILL PASS SOUTH OF NEW ENGLAND BRINGING ANOTHER PERIOD OF
PRECIPITATION MONDAY NIGHT AND TUESDAY. A MUCH STRONGER STORM
PASSING WEST OF NEW ENGLAND WILL BRING HEAVY RAINFALL...GUSTY
WINDS AND COASTAL FLOODING CONCERNS TO THE REGION WEDNESDAY AND
WEDNESDAY NIGHT. DRY BUT VERY WINDY CONDITIONS FOLLOW FOR
CHRISTMAS DAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...

700 PM UPDATE...

VERY LITTLE CHANGES TO THE FORECAST AS OVERALL TREND IS ON TRACK
FOR THIS MORNING. RADAR ECHOES LOOK A LITTLE DECEIVING AS SNOW HAS
SPREAD ACROSS A GOOD PORTION OF SOUTHERN NEW ENGLAND PER OBS.
ANTICIPATE MORE WIDE SPREAD BUT LIGHT SNOW OVER THE NEXT HOUR OR
TWO OUTSIDE OF THE COASTAL FRONT...WHICH IS DRAPED OVER GHG-TAN-
UUU.

PREVIOUS DISCUSSION...

APPROACHING SHORTWAVE HAS ALLOWED AN AREA LIGHT SNOW SHOWERS TO
EXPAND SOUTH OF THE MA TURNPIKE VERY EARLY THIS MORNING...BUT A FEW
SNOW SHOWERS DID EXTEND INTO NORTHERN MA.  RADAR IMAGERY ACTUALLY
OVER SHOOTING SOME OF THE ACTIVITY ACROSS NORTHERN CT...BASED ON
OBSERVATIONS.  THE RAIN/SNOW LINE RUNS ROUGHLY FROM NEWPORT...TO
TAUNTON AND JUST NORTH OF MARSHFIELD.  OVERALL...DO NOT EXPECT MUCH
CHANGE IN THE RAIN/SNOW LINE THIS MORNING BASED ON THERMAL PROFILES
AND POSITIONING OF THE COASTAL FRONT.

MAIN UNCERTAINTY IS JUST HOW MUCH SNOW OCCURS THIS MORNING WITH THE
SHORTWAVE MOVING ACROSS CT.  GIVEN THE TRACK OF THE SHORTWAVE...BEST
FORCING WILL BE LOCATED SOUTH OF THE MA TURNPIKE AND ESPECIALLY
ACROSS NORTHERN CT/RI.  WE WILL FORECAST 1 TO 2 INCHES OF SNOW
ACROSS THIS REGION...BUT A FEW ISOLATED 3 INCH AMOUNTS CAN NOT BE
RULED OUT. MEANWHILE...AREAS NORTH OF THE MA TURNPIKE WILL BE
REMOVED FROM THE BEST FORCING...BUT STILL SEE SOME SCATTERED
SHOWERS.  ACCUMS IN THIS AREA LIKELY TO BE A DUSTING TO LESS THAN AN
INCH.

ALSO...SOME OF THE PRECIPITATION CURRENTLY ACROSS SOUTHEAST MA IS
BEING ENHANCED FROM THE COASTAL FRONT.  A LOT OF THIS PRECIP WILL
BE IN THE FORM OF RAIN SHOWERS ACROSS PLYMOUTH AND EVEN INTO
PORTIONS OF BRISTOL COUNTY...POINTS SOUTH AND EAST.  HOWEVER...AT
LEAST THE SLIGHTLY HIGHER TERRAIN OF SOUTHEAST MA SHOULD SEE SNOW
SHOWERS.  WILL HAVE TO KEEP A CLOSE EYE ON IF COASTAL FRONT SHIFTS
SLIGHTLY THIS MORNING.  IT COULD MEAN THE DIFFERENCE BETWEEN AN AREA
GETTING MAINLY RAIN SHOWERS OR PERHAPS AN INCH OR SO OF SNOW.
OVERALL...DO NOT EXPECT THE COASTAL FRONT TO MOVE TOO MUCH THIS
MORNING...BUT JUST A FEW MILES CAN MAKE DIFFERENCE FOR A
PARTICULARLY NEIGHBORHOOD.

BULK OF PRECIPITATION WILL BE THIS MORNING WITH THE SHORTWAVE.
HOWEVER...ENOUGH LOW LEVEL MOISTURE/WEAK LIFT WILL REMAIN THIS
AFTERNOON FOR AT LEAST THIS RISK OF SCATTERED PRECIPITATION AND WILL
MAINTAIN SOME POPS.  HIGH TEMPS MAINLY IN THE 30S.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...
TONIGHT...

A RATHER CLOUDY AND RAW NIGHT ACROSS SOUTHERN NEW ENGLAND.  WHILE
THERE IS NOT A SIGNIFICANT SHORTWAVE TO TRIGGER A LOT OF
PRECIPITATION...PLENTY OF LOW LEVEL MOISTURE/WEAK SHALLOW LIFT
REMAINS.  THIS MAY BE ENOUGH TO RESULT IN A FEW RAIN/SNOW SHOWER
FROM TIME TO TIME.  PTYPE...WOULD BE MAINLY SNOW SHOWERS EXCEPT TO
THE SOUTHEAST OF A NEWPORT...TO TAUNTON...TO JUST NORTH OF
MARSHFIELD LINE.  AGAIN...MUCH OF THE NIGHT WILL PROBABLY END UP
DRY...BUT JUST THE RISK FOR A FEW RAIN/SNOW SHOWERS.

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...
HIGHLIGHTS...

* WEAK SHORTWAVE ON MON NIGHT/TUESDAY COULD BRING WINTRY
  MIX/FREEZING RAIN TO THE INTERIOR
* ANOMALOUS SYSTEM ACROSS THE GREAT LAKES WILL BRING HEAVY
  RAIN...GUSTY WINDS AND COASTAL FLOODING CONCERNS AROUND CHRISTMAS
  EVE
* BLUSTERY BUT AIRMASS WILL BE DRYING OUT ON CHRISTMAS DAY

OVERVIEW...

THE MODELS AND ENSEMBLES OFFER A REASONABLY SIMILAR AND PREDICTABLE
LARGER SCALE MID TO UPPER LEVEL PATTERN EVOLUTION FOR MUCH OF THE
UPCOMING WEEK. THIS ACTIVE FLOW REGIME DEVELOPS SEVERAL MID-UPPER
LEVEL TROUGH AND ASSOCIATED/UNSETTLING LEAD SURFACE LOW/FRONTAL
SYSTEMS AND PCPN SWATHS PROGRESS STEADILY ACROSS THE LOWER 48. THE
FIRST AMPLIFIED/DEEP LEAD SYSTEM WORKS ACROSS THE ERN/NERN US INTO
ERN CANADA CHRISTMAS EVE INTO CHRISTMAS ALLOWING FOR A MOIST/WARMED
AIRMASS IN ADVANCE OF FRONTAL APPROACH WITH HEAVIEST LEAD QPF
POTENTIAL OVER NEW ENGLAND. BIGGEST QUESTION IS THE EVOLUTION OF THE
SECONDARY LOW PRESSURE SYSTEM. 00Z GUIDANCE HAS BACKED OFF ON THE
STRENGTH OF THE LOW AND IS HAVING ISSUES ON HOW TO HANDLE ITS
EVOLUTION. THE EC AND GFS HAVE SLOWED DOWN THE SYSTEM SLIGHTLY WITH
THE EC HAVING MORE OF A NEGATIVE TROUGH VS THE GFS. BELIEVE THE
UKMET IS A GOOD COMPROMISE AT IS WAS THE FIRST DETERMINISTIC
GUIDANCE ON TAMPERING DOWN THE FIRST MAIN LOW...WHILE THE CMC IS OUT
TO LUNCH. REGARDLESS THIS IS A VERY ANOMALOUS SYSTEM THAT IS ABOUT 4
STANDARD DEVIATIONS AWAY.

A SECONDARY SYSTEM DEEPENS ACROSS THE FOUR CORNERS ON FRIDAY AND
WITH THE STUBBORN TROUGH OVER THE CENTRAL U.S...IT WILL PUSH A
SYSTEM TOWARDS SOUTHERN NEW ENGLAND BY SUNDAY. THIS SYSTEM MAY
SUPPORT A MODEST SWATH OF OVERRUNNING SNOW OVER SOUTHERN NEW
ENGLAND.

DETAILS...

MONDAY INTO TUESDAY...MODERATE CONFIDENCE.

A WEAK WAVE OF LOW PRESSURE DEVELOPS ALONG THE SOUTHEAST COAST
MONDAY...AND WILL BE ON A DEVELOPING WARM FRONTAL BOUNDARY. THIS LOW
REMAINS WEAK AS THE WARM FRONT MOVES SLOWLY NORTH MONDAY NIGHT INTO
TUESDAY. APPEARS THAT THERE IS DECENT WARM ADVECTION AHEAD OF THIS
WAVE. SEVERAL HI-RES GUIDANCE MODELS SHOW THAT THERE IS THE
POTENTIAL FOR COLD AIR DAMMING ACROSS THE INTERIOR INTO TUESDAY.
BIGGEST QUESTION WILL BE IS THERE ENOUGH MOISTURE FOR PRECIP DURING
THIS TIME FRAME. DUE TO A STRENGTHENING LLJ PROVIDING A GOOD SOURCE OF
LIFT ANTICIPATE PRECIP TO DEVELOP AND OVERSPREAD ACROSS SOUTHERN NEW
ENGLAND. IF THIS PLAYS OUT WITH COLD AIR DAMMING AND WARM AIR
ADVECTION...THEN WE COULD SEE FREEZING RAIN/DRIZZLE ACROSS THE I-91
CORRIDOR LATE MONDAY INTO TUESDAY MORNING. DURING THE DAY ON
TUESDAY...GOOD AMOUNT OF WARM AIR WILL PUSH SURFACE TEMPS ABOVE
FREEZING BY THE LATE MORNING ALLOWING FOR ANY PRECIP TO BE MORE OF
THE LIQUID VARIETY AHEAD OF THE CHRISTMAS EVE STORM. HOWEVER
GUIDANCE IS ALWAYS TOO FAST IN SCOURING TEMPS OUT ESP ACROSS THE CT
VALLEY SO WE WILL NEED TO MONITOR THIS CLOSELY...ESP DUE TO LIGHT
WINDS AND THE HIGH IN EASTERN CANADA. A WINTER WX ADVISORY MAY BE
NEEDED FOR THE LIGHT ICING POTENTIAL.

WE COULD ALSO SEE SOME MINOR COASTAL FLOODING CONCERNS ON TUESDAY. SEE
BELOW FOR MORE DETAILS.

WEDNESDAY INTO THURSDAY...HIGH CONFIDENCE IN SYSTEM LOW CONFIDENCE
ON DETAILS.

ANOMALOUS SYSTEM WILL STRENGTHEN OVER THE GREAT LAKES TUESDAY INTO
WEDNESDAY. A SECONDARY SHORTWAVE WILL ROUND THE DEEP TROUGH AND
DEVELOP A SECONDARY LOW PRESSURE ALONG THE COLD FRONT. THIS
SECONDARY LOW WILL STRENGTHEN AND PASS WEST OF SOUTHERN NEW ENGLAND.
THIS SYSTEM WILL CONTINUE TO DEEPEN AS IT MOVES TOWARDS EASTERN
CANADA SWINGING A COLD FRONT ACROSS THE NORTHEAST.

STRONG SOUTHERLY JET OUT AHEAD OF THE FRONT WITH A GULF MOISTURE
CONNECTION WILL IMPACT SOUTHERN NEW ENGLAND ON CHRISTMAS EVE. THIS
STRONG JET WILL YIELD FOR PCPN IN THE LIQUID VARIETY.  PW ANOMALIES
ARE BETWEEN +4 TO +5 STANDARD DEVIATIONS ABOVE NORMAL WHICH IS QUITE
ANOMALOUS FOR THIS TIME OF YEAR. IN FACT CURRENT PWATS ARE PROGGED
ABOVE 1.6 INCHES WITH MODEL QPF OVER 2 INCHES...AT THE VERY LEAST
COULD SEE URBAN AND POOR DRAINAGE FLOODING. LATEST EC EVEN SHOWS
OVER 2.5 INCHES OF QPF...AND WITH THE TROPICAL CONNECTION AND STRONG
SOUTHERLY FLOW COULD SEE HIGHER AMOUNTS DUE TO TOPOGRAPHY
ENHANCEMENTS. RAINFALL RECORDS MAY FALL IF EVERYTHING FALLS INTO
PLACE.

AHEAD OF THE FRONT...SOUTHERN NEW ENGLAND WILL WARM SECTOR WED INTO
THUR MORNING ALLOWING FOR TEMPERATURES TO BE WELL ABOVE AVERAGE. IN
FACT WE MAY BE CLOSE AT BREAKING RECORD HIGH TEMPS IF TEMPS WARM TO
60F OR ABOVE ON CHRISTMAS EVE. SINCE WE WILL BE IN THE WARM
SECTOR...AND SHOWALTERS CLOSE TO ZERO...ISOLATED THUNDER IS STILL
POSSIBLE.

STRONG LOW LEVEL WINDS WILL ALSO BE A CONCERN ESPECIALLY WEDNESDAY
NIGHT. THE ECMWF SHOWS EAST-SOUTHEAST WINDS 30-40 KNOTS ON WEDNESDAY
INCREASING TO 60-75 KNOTS BY WEDNESDAY NIGHT. STRONG DOWNPOURS MAY
OVERCOME THE LOW LEVEL INVERSION AND BRING STRONG GUSTS OF AT LEAST
30-40 KNOTS ESPECIALLY ALONG THE SOUTH COAST. A WIND ADVISORY MAY BE
NEEDED IN SOME AREAS.

CHRISTMAS DAY...MODERATE CONFIDENCE.

AS THE COLD FRONT PASSES THROUGH EARLY CHRISTMAS DAY...THE WEST
WINDS WILL HELP DRY THE AIRMASS ALLOWING FOR PARTLY SUNNY SKIES.
STRONG CAA ON THURSDAY WILL ALLOW DESCENT MIXING. WINDS IN THE SFC-
850 MB LAYER WILL BE 30-40 KNOTS AND POSSIBLY A LITTLE
HIGHER...WHICH WOULD REQUIRE A WIND ADVISORY FOR MUCH OF THE AREA.

FRIDAY-SUNDAY...LOWER CONFIDENCE

WEAK HIGH PRESSURE BUILDS OVER THE AREA FRIDAY INTO SATURDAY. THE
NEXT SHORTWAVE APPROACHES LATE SATURDAY INTO SUNDAY AND SHOULD BRING
INCREASING CLOUDS FROM WEST TO EAST ALONG WITH A CHANCE OF RAIN OR
SNOW SHOWERS MAINLY IN THE AFTERNOON AND AT NIGHT.

&&

.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /TODAY AND TONIGHT/...

TODAY AND TONIGHT...MODERATE CONFIDENCE.  MAINLY MVFR CONDITIONS
SOUTH OF THE MA TURNPIKE WITH BORDERLINE VFR TO MARGINAL MVFR CIGS
NORTH OF THE PIKE THROUGH TONIGHT.  AN AREA OF SNOW SHOWERS WILL
EXPAND MAINLY ACROSS AREAS SOUTH OF THE PIKE THIS MORNING...BUT A
FEW SNOW SHOWERS WILL STILL AFFECT NORTHERN MA.  VSBYS/CIGS MAY
BRIEFLY DROP TO IFR LEVELS IN NORTHERN CT/RI/SE MA.  PTYPE WILL BE
RAIN SHOWERS ACROSS MOST OF PLYMOUTH COUNTY AND ONTO THE
CAPE/ISLANDS WITH SNOW SHOWERS NORTH AND WEST.  BULK OF PRECIP THIS
MORNING...BUT A FEW LINGERING RAIN/SNOW SHOWERS STILL POSSIBLE THIS
AFTERNOON AND EVENING.

KBOS TERMINAL...MODERATE CONFIDENCE.  A FEW SNOW SHOWERS POSSIBLE
THIS MORNING BUT BULK OF ACTIVITY SHOULD BE SOUTH OF THE TERMINAL.

KBDL TERMINAL...MODERATE CONFIDENCE.  PERIOD OF SNOW SHOWERS THIS
MORNING MAY DROP AN INCH OR TWO OF SNOW.  MVFR CONDITIONS DOMINATE
TODAY....BUT A BRIEF PERIOD OF IFR CONDITIONS ARE POSSIBLE THIS
MORNING IN SNOW SHOWERS.

OUTLOOK...MONDAY THROUGH THURSDAY...MODERATE CONFIDENCE.

MONDAY...MVFR CIGS CONTINUE IN RI/EASTERN MASS IN MARINE EAST FLOW.
VFR IN THE WEST.

TUESDAY...VFR WITH SCATTERED MVFR IN ANY RAIN/SNOW SHOWERS.

WEDNESDAY...CONDITIONS LOWERING TO IFR IN RAIN/HEAVY RAIN. ISOLATED
THUNDERSTORMS POSSIBLE ESPECIALLY WEDNESDAY NIGHT. EAST-SOUTHEAST
SURFACE WINDS MAY GUST TO 35-45 KNOTS. WINDS AT 2000 FEET AGL WILL
REACH 50-60 KNOTS WEDNESDAY AFTERNOON AND EARLY NIGHT CREATING LOW
LEVEL WIND SHEAR CONCERNS.

CHRISTMAS DAY...WEST WIND GUSTING 30-40 KNOTS. CONDITIONS IMPROVING
TO VFR AS THE WIND BRINGS IN COOLER DRIER AIR.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /TODAY AND TONIGHT/...HIGH CONFIDENCE.

HIGH PRESSURE ACROSS QUEBEC WILL RESULT IN NORTHEAST WINDS ACROSS
THE WATERS THAT WILL GUST TO BETWEEN 15 AND 20 KNOTS.  THIS WILL
RESULT IN 2 TO 4 FOOT SEAS.  HOWEVER...NO HEADLINES PLANNED AS
CONDITIONS SHOULD REMAIN BELOW SMALL CRAFT ADVISORY THRESHOLDS.

OUTLOOK...MONDAY THROUGH THURSDAY...MODERATE CONFIDENCE

MONDAY...EAST TO NORTHEAST WINDS GUSTING AROUND 15 KNOTS OR LESS.
SEAS WILL HOLD AROUND 3-4 FEET...MAY INCREASE TO 5FT IN NORTHEAST
FLOW AS GUIDANCE MAY BE UNDERDONE.

TUESDAY... INCREASING EAST WINDS WITH FREQUENT GUSTS 25 TO 30 KNOTS.
SEAS WILL BUILD TO 5-6 FEET ON THE EXPOSED WATERS.  A SMALL CRAFT
ADVISORY MAY BE NEEDED.

WEDNESDAY...RAIN WILL BE HEAVY AT TIMES PRODUCING POOR VISIBILITY.
INCREASING SOUTHEAST WINDS 20-25 SUSTAINED AND 40 KNOT GUSTS.  WINDS
SHOULD SHIFT TO SOUTH WEDNESDAY NIGHT AND SOUTHWEST TOWARD THURSDAY
MORNING. RAIN WILL TAPER OFF WITH THE WIND SHIFT TO SOUTHWEST. SEAS
WILL CONTINUE TO BUILD WITH 7-11 FEET HEIGHTS ON THE EXPOSED WATERS.
A GALE WARNING WILL BE NEEDED...WITH A LOW PROB OF A FEW STORM FORCE
GUSTS ACROSS THE EASTERN OUTER WATERS.

CHRISTMAS DAY... WEST SOUTHWEST WINDS WILL CONTINUE TO GUST 35-40
KNOTS...SO A CONTINUED GALE WARNING MAY BE NEEDED. SEAS OF 7-15 FEET
ARE POSSIBLE ON THE EXPOSED WATERS...AND 5 FEET IS POSSIBLE ON SOME
OF THE NEARSHORE WATERS.

&&

.TIDES/COASTAL FLOODING...
HIGH ASTRONOMICAL TIDES WILL OCCUR TUESDAY THROUGH THURSDAY. BREAKING
IT DOWN...ON TUESDAY HIGH TIDE AT BOSTON WILL BE 11.6 FT. THERE WILL
BE ONSHORE FLOW DURING THIS HIGH TIDE ALLOWING FOR MINOR SPLASHOVER.
IF WIND GUSTS INCREASE THEN COULD POSSIBLE SEE MINOR COASTAL
FLOODING.

ON WEDNESDAY...WINDS WILL SWITCH TO A MORE SOUTHEASTERLY FLOW DURING
THE DAY AND INCREASE QUICKLY FROM APPROACHING SYSTEM AND DECENT
PRESSURE FALLS. WEDNESDAY AFTERNOON HIGH TIDE IN BOSTON IS 11.7 FT
AND WITH ANY STRENGTH ON THE EASTERLY WIND FLOW WILL PUSH THE TIDE
OVER. RIGHT NOW BELIEVE MINOR COASTAL FLOODING IS POSSIBLE ALONG THE
EAST COASTLINE.

WEDNESDAY EVENING...THE WIND GOES IN A MORE SOUTHERLY DIRECTION AND
THE TIDE WILL BE INCREASE ACROSS THE SOUTH COAST. HIGH TIDE IN
PROVIDENCE WILL BE 5.2 FT. 925 MB LLJ STRENGTHENS TO 50-60 KTS WHICH
COULD PUSH A DECENT SURGE UP ALONG THE SOUTH COAST DURING THE TIME
OF HIGH TIDE. THINKING THAT MINOR COASTAL FLOODING COULD OCCUR BUT
CANNOT RULE OUT MODERATE ALONG THE SOUTH COAST...ESP IF LLJ
STRENGTHENS EVEN MORE.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...FRANK/DUNTEN
NEAR TERM...FRANK/DUNTEN
SHORT TERM...FRANK
LONG TERM...DUNTEN
AVIATION...FRANK/DUNTEN
MARINE...FRANK/DUNTEN
TIDES/COASTAL FLOODING...STAFF



000
FXUS61 KBOX 211154
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
654 AM EST SUN DEC 21 2014

.SYNOPSIS...
AN AREA OF SNOW SHOWERS WILL AFFECT AREAS MAINLY SOUTH OF THE MA
TURNPIKE THIS MORNING...EXCEPT IT WILL BE MILD ENOUGH FOR RAIN
SHOWERS ACROSS THE FAR SOUTHEAST NEW ENGLAND COAST. WEAK LOW
PRESSURE WILL PASS SOUTH OF NEW ENGLAND BRINGING ANOTHER PERIOD OF
PRECIPITATION MONDAY NIGHT AND TUESDAY. A MUCH STRONGER STORM
PASSING WEST OF NEW ENGLAND WILL BRING HEAVY RAINFALL...GUSTY
WINDS AND COASTAL FLOODING CONCERNS TO THE REGION WEDNESDAY AND
WEDNESDAY NIGHT. DRY BUT VERY WINDY CONDITIONS FOLLOW FOR
CHRISTMAS DAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...

700 PM UPDATE...

VERY LITTLE CHANGES TO THE FORECAST AS OVERALL TREND IS ON TRACK
FOR THIS MORNING. RADAR ECHOES LOOK A LITTLE DECEIVING AS SNOW HAS
SPREAD ACROSS A GOOD PORTION OF SOUTHERN NEW ENGLAND PER OBS.
ANTICIPATE MORE WIDE SPREAD BUT LIGHT SNOW OVER THE NEXT HOUR OR
TWO OUTSIDE OF THE COASTAL FRONT...WHICH IS DRAPED OVER GHG-TAN-
UUU.

PREVIOUS DISCUSSION...

APPROACHING SHORTWAVE HAS ALLOWED AN AREA LIGHT SNOW SHOWERS TO
EXPAND SOUTH OF THE MA TURNPIKE VERY EARLY THIS MORNING...BUT A FEW
SNOW SHOWERS DID EXTEND INTO NORTHERN MA.  RADAR IMAGERY ACTUALLY
OVER SHOOTING SOME OF THE ACTIVITY ACROSS NORTHERN CT...BASED ON
OBSERVATIONS.  THE RAIN/SNOW LINE RUNS ROUGHLY FROM NEWPORT...TO
TAUNTON AND JUST NORTH OF MARSHFIELD.  OVERALL...DO NOT EXPECT MUCH
CHANGE IN THE RAIN/SNOW LINE THIS MORNING BASED ON THERMAL PROFILES
AND POSITIONING OF THE COASTAL FRONT.

MAIN UNCERTAINTY IS JUST HOW MUCH SNOW OCCURS THIS MORNING WITH THE
SHORTWAVE MOVING ACROSS CT.  GIVEN THE TRACK OF THE SHORTWAVE...BEST
FORCING WILL BE LOCATED SOUTH OF THE MA TURNPIKE AND ESPECIALLY
ACROSS NORTHERN CT/RI.  WE WILL FORECAST 1 TO 2 INCHES OF SNOW
ACROSS THIS REGION...BUT A FEW ISOLATED 3 INCH AMOUNTS CAN NOT BE
RULED OUT. MEANWHILE...AREAS NORTH OF THE MA TURNPIKE WILL BE
REMOVED FROM THE BEST FORCING...BUT STILL SEE SOME SCATTERED
SHOWERS.  ACCUMS IN THIS AREA LIKELY TO BE A DUSTING TO LESS THAN AN
INCH.

ALSO...SOME OF THE PRECIPITATION CURRENTLY ACROSS SOUTHEAST MA IS
BEING ENHANCED FROM THE COASTAL FRONT.  A LOT OF THIS PRECIP WILL
BE IN THE FORM OF RAIN SHOWERS ACROSS PLYMOUTH AND EVEN INTO
PORTIONS OF BRISTOL COUNTY...POINTS SOUTH AND EAST.  HOWEVER...AT
LEAST THE SLIGHTLY HIGHER TERRAIN OF SOUTHEAST MA SHOULD SEE SNOW
SHOWERS.  WILL HAVE TO KEEP A CLOSE EYE ON IF COASTAL FRONT SHIFTS
SLIGHTLY THIS MORNING.  IT COULD MEAN THE DIFFERENCE BETWEEN AN AREA
GETTING MAINLY RAIN SHOWERS OR PERHAPS AN INCH OR SO OF SNOW.
OVERALL...DO NOT EXPECT THE COASTAL FRONT TO MOVE TOO MUCH THIS
MORNING...BUT JUST A FEW MILES CAN MAKE DIFFERENCE FOR A
PARTICULARLY NEIGHBORHOOD.

BULK OF PRECIPITATION WILL BE THIS MORNING WITH THE SHORTWAVE.
HOWEVER...ENOUGH LOW LEVEL MOISTURE/WEAK LIFT WILL REMAIN THIS
AFTERNOON FOR AT LEAST THIS RISK OF SCATTERED PRECIPITATION AND WILL
MAINTAIN SOME POPS.  HIGH TEMPS MAINLY IN THE 30S.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...
TONIGHT...

A RATHER CLOUDY AND RAW NIGHT ACROSS SOUTHERN NEW ENGLAND.  WHILE
THERE IS NOT A SIGNIFICANT SHORTWAVE TO TRIGGER A LOT OF
PRECIPITATION...PLENTY OF LOW LEVEL MOISTURE/WEAK SHALLOW LIFT
REMAINS.  THIS MAY BE ENOUGH TO RESULT IN A FEW RAIN/SNOW SHOWER
FROM TIME TO TIME.  PTYPE...WOULD BE MAINLY SNOW SHOWERS EXCEPT TO
THE SOUTHEAST OF A NEWPORT...TO TAUNTON...TO JUST NORTH OF
MARSHFIELD LINE.  AGAIN...MUCH OF THE NIGHT WILL PROBABLY END UP
DRY...BUT JUST THE RISK FOR A FEW RAIN/SNOW SHOWERS.

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...
HIGHLIGHTS...

* WEAK SHORTWAVE ON MON NIGHT/TUESDAY COULD BRING WINTRY
  MIX/FREEZING RAIN TO THE INTERIOR
* ANOMALOUS SYSTEM ACROSS THE GREAT LAKES WILL BRING HEAVY
  RAIN...GUSTY WINDS AND COASTAL FLOODING CONCERNS AROUND CHRISTMAS
  EVE
* BLUSTERY BUT AIRMASS WILL BE DRYING OUT ON CHRISTMAS DAY

OVERVIEW...

THE MODELS AND ENSEMBLES OFFER A REASONABLY SIMILAR AND PREDICTABLE
LARGER SCALE MID TO UPPER LEVEL PATTERN EVOLUTION FOR MUCH OF THE
UPCOMING WEEK. THIS ACTIVE FLOW REGIME DEVELOPS SEVERAL MID-UPPER
LEVEL TROUGH AND ASSOCIATED/UNSETTLING LEAD SURFACE LOW/FRONTAL
SYSTEMS AND PCPN SWATHS PROGRESS STEADILY ACROSS THE LOWER 48. THE
FIRST AMPLIFIED/DEEP LEAD SYSTEM WORKS ACROSS THE ERN/NERN US INTO
ERN CANADA CHRISTMAS EVE INTO CHRISTMAS ALLOWING FOR A MOIST/WARMED
AIRMASS IN ADVANCE OF FRONTAL APPROACH WITH HEAVIEST LEAD QPF
POTENTIAL OVER NEW ENGLAND. BIGGEST QUESTION IS THE EVOLUTION OF THE
SECONDARY LOW PRESSURE SYSTEM. 00Z GUIDANCE HAS BACKED OFF ON THE
STRENGTH OF THE LOW AND IS HAVING ISSUES ON HOW TO HANDLE ITS
EVOLUTION. THE EC AND GFS HAVE SLOWED DOWN THE SYSTEM SLIGHTLY WITH
THE EC HAVING MORE OF A NEGATIVE TROUGH VS THE GFS. BELIEVE THE
UKMET IS A GOOD COMPROMISE AT IS WAS THE FIRST DETERMINISTIC
GUIDANCE ON TAMPERING DOWN THE FIRST MAIN LOW...WHILE THE CMC IS OUT
TO LUNCH. REGARDLESS THIS IS A VERY ANOMALOUS SYSTEM THAT IS ABOUT 4
STANDARD DEVIATIONS AWAY.

A SECONDARY SYSTEM DEEPENS ACROSS THE FOUR CORNERS ON FRIDAY AND
WITH THE STUBBORN TROUGH OVER THE CENTRAL U.S...IT WILL PUSH A
SYSTEM TOWARDS SOUTHERN NEW ENGLAND BY SUNDAY. THIS SYSTEM MAY
SUPPORT A MODEST SWATH OF OVERRUNNING SNOW OVER SOUTHERN NEW
ENGLAND.

DETAILS...

MONDAY INTO TUESDAY...MODERATE CONFIDENCE.

A WEAK WAVE OF LOW PRESSURE DEVELOPS ALONG THE SOUTHEAST COAST
MONDAY...AND WILL BE ON A DEVELOPING WARM FRONTAL BOUNDARY. THIS LOW
REMAINS WEAK AS THE WARM FRONT MOVES SLOWLY NORTH MONDAY NIGHT INTO
TUESDAY. APPEARS THAT THERE IS DECENT WARM ADVECTION AHEAD OF THIS
WAVE. SEVERAL HI-RES GUIDANCE MODELS SHOW THAT THERE IS THE
POTENTIAL FOR COLD AIR DAMMING ACROSS THE INTERIOR INTO TUESDAY.
BIGGEST QUESTION WILL BE IS THERE ENOUGH MOISTURE FOR PRECIP DURING
THIS TIME FRAME. DUE TO A STRENGTHENING LLJ PROVIDING A GOOD SOURCE OF
LIFT ANTICIPATE PRECIP TO DEVELOP AND OVERSPREAD ACROSS SOUTHERN NEW
ENGLAND. IF THIS PLAYS OUT WITH COLD AIR DAMMING AND WARM AIR
ADVECTION...THEN WE COULD SEE FREEZING RAIN/DRIZZLE ACROSS THE I-91
CORRIDOR LATE MONDAY INTO TUESDAY MORNING. DURING THE DAY ON
TUESDAY...GOOD AMOUNT OF WARM AIR WILL PUSH SURFACE TEMPS ABOVE
FREEZING BY THE LATE MORNING ALLOWING FOR ANY PRECIP TO BE MORE OF
THE LIQUID VARIETY AHEAD OF THE CHRISTMAS EVE STORM. HOWEVER
GUIDANCE IS ALWAYS TOO FAST IN SCOURING TEMPS OUT ESP ACROSS THE CT
VALLEY SO WE WILL NEED TO MONITOR THIS CLOSELY...ESP DUE TO LIGHT
WINDS AND THE HIGH IN EASTERN CANADA. A WINTER WX ADVISORY MAY BE
NEEDED FOR THE LIGHT ICING POTENTIAL.

WE COULD ALSO SEE SOME MINOR COASTAL FLOODING CONCERNS ON TUESDAY. SEE
BELOW FOR MORE DETAILS.

WEDNESDAY INTO THURSDAY...HIGH CONFIDENCE IN SYSTEM LOW CONFIDENCE
ON DETAILS.

ANOMALOUS SYSTEM WILL STRENGTHEN OVER THE GREAT LAKES TUESDAY INTO
WEDNESDAY. A SECONDARY SHORTWAVE WILL ROUND THE DEEP TROUGH AND
DEVELOP A SECONDARY LOW PRESSURE ALONG THE COLD FRONT. THIS
SECONDARY LOW WILL STRENGTHEN AND PASS WEST OF SOUTHERN NEW ENGLAND.
THIS SYSTEM WILL CONTINUE TO DEEPEN AS IT MOVES TOWARDS EASTERN
CANADA SWINGING A COLD FRONT ACROSS THE NORTHEAST.

STRONG SOUTHERLY JET OUT AHEAD OF THE FRONT WITH A GULF MOISTURE
CONNECTION WILL IMPACT SOUTHERN NEW ENGLAND ON CHRISTMAS EVE. THIS
STRONG JET WILL YIELD FOR PCPN IN THE LIQUID VARIETY.  PW ANOMALIES
ARE BETWEEN +4 TO +5 STANDARD DEVIATIONS ABOVE NORMAL WHICH IS QUITE
ANOMALOUS FOR THIS TIME OF YEAR. IN FACT CURRENT PWATS ARE PROGGED
ABOVE 1.6 INCHES WITH MODEL QPF OVER 2 INCHES...AT THE VERY LEAST
COULD SEE URBAN AND POOR DRAINAGE FLOODING. LATEST EC EVEN SHOWS
OVER 2.5 INCHES OF QPF...AND WITH THE TROPICAL CONNECTION AND STRONG
SOUTHERLY FLOW COULD SEE HIGHER AMOUNTS DUE TO TOPOGRAPHY
ENHANCEMENTS. RAINFALL RECORDS MAY FALL IF EVERYTHING FALLS INTO
PLACE.

AHEAD OF THE FRONT...SOUTHERN NEW ENGLAND WILL WARM SECTOR WED INTO
THUR MORNING ALLOWING FOR TEMPERATURES TO BE WELL ABOVE AVERAGE. IN
FACT WE MAY BE CLOSE AT BREAKING RECORD HIGH TEMPS IF TEMPS WARM TO
60F OR ABOVE ON CHRISTMAS EVE. SINCE WE WILL BE IN THE WARM
SECTOR...AND SHOWALTERS CLOSE TO ZERO...ISOLATED THUNDER IS STILL
POSSIBLE.

STRONG LOW LEVEL WINDS WILL ALSO BE A CONCERN ESPECIALLY WEDNESDAY
NIGHT. THE ECMWF SHOWS EAST-SOUTHEAST WINDS 30-40 KNOTS ON WEDNESDAY
INCREASING TO 60-75 KNOTS BY WEDNESDAY NIGHT. STRONG DOWNPOURS MAY
OVERCOME THE LOW LEVEL INVERSION AND BRING STRONG GUSTS OF AT LEAST
30-40 KNOTS ESPECIALLY ALONG THE SOUTH COAST. A WIND ADVISORY MAY BE
NEEDED IN SOME AREAS.

CHRISTMAS DAY...MODERATE CONFIDENCE.

AS THE COLD FRONT PASSES THROUGH EARLY CHRISTMAS DAY...THE WEST
WINDS WILL HELP DRY THE AIRMASS ALLOWING FOR PARTLY SUNNY SKIES.
STRONG CAA ON THURSDAY WILL ALLOW DESCENT MIXING. WINDS IN THE SFC-
850 MB LAYER WILL BE 30-40 KNOTS AND POSSIBLY A LITTLE
HIGHER...WHICH WOULD REQUIRE A WIND ADVISORY FOR MUCH OF THE AREA.

FRIDAY-SUNDAY...LOWER CONFIDENCE

WEAK HIGH PRESSURE BUILDS OVER THE AREA FRIDAY INTO SATURDAY. THE
NEXT SHORTWAVE APPROACHES LATE SATURDAY INTO SUNDAY AND SHOULD BRING
INCREASING CLOUDS FROM WEST TO EAST ALONG WITH A CHANCE OF RAIN OR
SNOW SHOWERS MAINLY IN THE AFTERNOON AND AT NIGHT.

&&

.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /TODAY AND TONIGHT/...

TODAY AND TONIGHT...MODERATE CONFIDENCE.  MAINLY MVFR CONDITIONS
SOUTH OF THE MA TURNPIKE WITH BORDERLINE VFR TO MARGINAL MVFR CIGS
NORTH OF THE PIKE THROUGH TONIGHT.  AN AREA OF SNOW SHOWERS WILL
EXPAND MAINLY ACROSS AREAS SOUTH OF THE PIKE THIS MORNING...BUT A
FEW SNOW SHOWERS WILL STILL AFFECT NORTHERN MA.  VSBYS/CIGS MAY
BRIEFLY DROP TO IFR LEVELS IN NORTHERN CT/RI/SE MA.  PTYPE WILL BE
RAIN SHOWERS ACROSS MOST OF PLYMOUTH COUNTY AND ONTO THE
CAPE/ISLANDS WITH SNOW SHOWERS NORTH AND WEST.  BULK OF PRECIP THIS
MORNING...BUT A FEW LINGERING RAIN/SNOW SHOWERS STILL POSSIBLE THIS
AFTERNOON AND EVENING.

KBOS TERMINAL...MODERATE CONFIDENCE.  A FEW SNOW SHOWERS POSSIBLE
THIS MORNING BUT BULK OF ACTIVITY SHOULD BE SOUTH OF THE TERMINAL.

KBDL TERMINAL...MODERATE CONFIDENCE.  PERIOD OF SNOW SHOWERS THIS
MORNING MAY DROP AN INCH OR TWO OF SNOW.  MVFR CONDITIONS DOMINATE
TODAY....BUT A BRIEF PERIOD OF IFR CONDITIONS ARE POSSIBLE THIS
MORNING IN SNOW SHOWERS.

OUTLOOK...MONDAY THROUGH THURSDAY...MODERATE CONFIDENCE.

MONDAY...MVFR CIGS CONTINUE IN RI/EASTERN MASS IN MARINE EAST FLOW.
VFR IN THE WEST.

TUESDAY...VFR WITH SCATTERED MVFR IN ANY RAIN/SNOW SHOWERS.

WEDNESDAY...CONDITIONS LOWERING TO IFR IN RAIN/HEAVY RAIN. ISOLATED
THUNDERSTORMS POSSIBLE ESPECIALLY WEDNESDAY NIGHT. EAST-SOUTHEAST
SURFACE WINDS MAY GUST TO 35-45 KNOTS. WINDS AT 2000 FEET AGL WILL
REACH 50-60 KNOTS WEDNESDAY AFTERNOON AND EARLY NIGHT CREATING LOW
LEVEL WIND SHEAR CONCERNS.

CHRISTMAS DAY...WEST WIND GUSTING 30-40 KNOTS. CONDITIONS IMPROVING
TO VFR AS THE WIND BRINGS IN COOLER DRIER AIR.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /TODAY AND TONIGHT/...HIGH CONFIDENCE.

HIGH PRESSURE ACROSS QUEBEC WILL RESULT IN NORTHEAST WINDS ACROSS
THE WATERS THAT WILL GUST TO BETWEEN 15 AND 20 KNOTS.  THIS WILL
RESULT IN 2 TO 4 FOOT SEAS.  HOWEVER...NO HEADLINES PLANNED AS
CONDITIONS SHOULD REMAIN BELOW SMALL CRAFT ADVISORY THRESHOLDS.

OUTLOOK...MONDAY THROUGH THURSDAY...MODERATE CONFIDENCE

MONDAY...EAST TO NORTHEAST WINDS GUSTING AROUND 15 KNOTS OR LESS.
SEAS WILL HOLD AROUND 3-4 FEET...MAY INCREASE TO 5FT IN NORTHEAST
FLOW AS GUIDANCE MAY BE UNDERDONE.

TUESDAY... INCREASING EAST WINDS WITH FREQUENT GUSTS 25 TO 30 KNOTS.
SEAS WILL BUILD TO 5-6 FEET ON THE EXPOSED WATERS.  A SMALL CRAFT
ADVISORY MAY BE NEEDED.

WEDNESDAY...RAIN WILL BE HEAVY AT TIMES PRODUCING POOR VISIBILITY.
INCREASING SOUTHEAST WINDS 20-25 SUSTAINED AND 40 KNOT GUSTS.  WINDS
SHOULD SHIFT TO SOUTH WEDNESDAY NIGHT AND SOUTHWEST TOWARD THURSDAY
MORNING. RAIN WILL TAPER OFF WITH THE WIND SHIFT TO SOUTHWEST. SEAS
WILL CONTINUE TO BUILD WITH 7-11 FEET HEIGHTS ON THE EXPOSED WATERS.
A GALE WARNING WILL BE NEEDED...WITH A LOW PROB OF A FEW STORM FORCE
GUSTS ACROSS THE EASTERN OUTER WATERS.

CHRISTMAS DAY... WEST SOUTHWEST WINDS WILL CONTINUE TO GUST 35-40
KNOTS...SO A CONTINUED GALE WARNING MAY BE NEEDED. SEAS OF 7-15 FEET
ARE POSSIBLE ON THE EXPOSED WATERS...AND 5 FEET IS POSSIBLE ON SOME
OF THE NEARSHORE WATERS.

&&

.TIDES/COASTAL FLOODING...
HIGH ASTRONOMICAL TIDES WILL OCCUR TUESDAY THROUGH THURSDAY. BREAKING
IT DOWN...ON TUESDAY HIGH TIDE AT BOSTON WILL BE 11.6 FT. THERE WILL
BE ONSHORE FLOW DURING THIS HIGH TIDE ALLOWING FOR MINOR SPLASHOVER.
IF WIND GUSTS INCREASE THEN COULD POSSIBLE SEE MINOR COASTAL
FLOODING.

ON WEDNESDAY...WINDS WILL SWITCH TO A MORE SOUTHEASTERLY FLOW DURING
THE DAY AND INCREASE QUICKLY FROM APPROACHING SYSTEM AND DECENT
PRESSURE FALLS. WEDNESDAY AFTERNOON HIGH TIDE IN BOSTON IS 11.7 FT
AND WITH ANY STRENGTH ON THE EASTERLY WIND FLOW WILL PUSH THE TIDE
OVER. RIGHT NOW BELIEVE MINOR COASTAL FLOODING IS POSSIBLE ALONG THE
EAST COASTLINE.

WEDNESDAY EVENING...THE WIND GOES IN A MORE SOUTHERLY DIRECTION AND
THE TIDE WILL BE INCREASE ACROSS THE SOUTH COAST. HIGH TIDE IN
PROVIDENCE WILL BE 5.2 FT. 925 MB LLJ STRENGTHENS TO 50-60 KTS WHICH
COULD PUSH A DECENT SURGE UP ALONG THE SOUTH COAST DURING THE TIME
OF HIGH TIDE. THINKING THAT MINOR COASTAL FLOODING COULD OCCUR BUT
CANNOT RULE OUT MODERATE ALONG THE SOUTH COAST...ESP IF LLJ
STRENGTHENS EVEN MORE.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...FRANK/DUNTEN
NEAR TERM...FRANK/DUNTEN
SHORT TERM...FRANK
LONG TERM...DUNTEN
AVIATION...FRANK/DUNTEN
MARINE...FRANK/DUNTEN
TIDES/COASTAL FLOODING...STAFF



000
FXUS61 KGYX 211116
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
616 AM EST SUN DEC 21 2014

.SYNOPSIS...
HIGH PRESSURE BUILDS OVER NORTHERN MAINE SUNDAY...ALLOWING THE
FLOW TO TURN ONSHORE. A WEAK WEATHER DISTURBANCE MAY TRIGGER SOME
FLURRIES OR LIGHT SNOW OVER SOUTHERN REGIONS RIGHT THROUGH MONDAY.
A SIGNIFICANT LOW PRESSURE SYSTEM SYSTEM WILL GRADUALLY ORGANIZE
WEDNESDAY...BEFORE MOVING OVER THE GREAT LAKES. THIS COULD BRING
WINDY CONDITIONS AND THE POTENTIAL FOR HEAVY RAIN AROUND CHRISTMAS
EVE INTO EARLY CHRISTMAS MORNING.

&&

.NEAR TERM /THROUGH TONIGHT/...
615 AM UPDATE...JUST MADE SOME MINOR UPDATES TO SKY AND
TEMPERATURES BASED ON CURRENT OBS AND TRENDS...AS STRATUS REMAINS
ENTRENCHED ACROSS THE REGION.

PREVIOUS DISCUSSION...
LOW STRATUS BLANKETS THE CWFA AS A SURFACE HIGH PRESSURE IN
SOUTHERN QUEBEC IS HELPING TO KEEP MOISTURE TRAPPED IN THE LOW
LEVELS. A WEAK SHORTWAVE THAT IS PASSING OVER THE SOUTHERN NEW
ENGLAND THIS MORNING AND THIS MAY HELP KICK OFF SOME LIGHT SNOW
ACROSS THE FAR SOUTHERN AREAS OF NEW HAMPSHIRE AND PARTS OF
SOUTHWEST MAINE...AS ON SHORE FLOW SUPPLIES THE LOW LEVEL MOISTURE
THE LIFT FROM THIS WEAK SHORT MAY BE JUST ENOUGH TO PRODUCE SNOW
SHOWERS HEAVY ENOUGH TO ACCUMULATE IN SOME AREAS. AS THIS WEAK
WAVE MOVES EAST OUR FLOW...ALTHOUGH VERY WEAK...WILL TURN TO
NORTHWESTERLY AND THIS MAY BE ENOUGH TO START CLEARING OUT SOME OF
THE LOW STRATUS SUNDAY NIGHT.

&&

.SHORT TERM /MONDAY/...
FLOW WILL SWITCH BACK TO ON SHORE BY NOON ON MONDAY AND THIS WILL
BRING LIGHT OCEAN EFFECT SNOW OR MAYBE EVEN SOME LIGHT RAIN OR
EVEN FREEZING DRIZZLE INTO THE INTERIOR AS TEMPERATURES WILL HOVER
CLOSE TO FREEZING AS YOU GET AWAY FROM THE COAST.

&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
MODELS CONTINUE TO TREND TOWARD UPSTREAM AND DOWNSTREAM
BLOCKING...WITH AN EVENTUAL RETURN TO A +PNA PATTERN AT
500MB...WHICH WOULD SIGNAL COOLING LATE IN THE PERIOD. HOWEVER
ALL THE ACTION WILL BE IN DAYS 3 TO 5 AS THE UPSTREAM DEVELOPS AND
SENDS WAVES INTO TROUGH OVER CENTRAL CONUS...AMPLIFYING THE 500
MB FLOW.

INITIALLY...WILL BE DEALING WITH SMALLER SCALE FEATURE AS
INVERTED TROUGH OVER THE GULF OF ME WORK ITS WAY ONSHORE MON NIGHT
AND WEAKENS. MAY BE ENOUGH DYNAMIC FORCING FOR ICE CRYSTALS
INITIALLY...SO RAIN OR SNOW SHOWERS MOVE ONSHORE AND INLAND DURING
THE EVENING...BUT COULD SEE IT TURN TO DZ/FZDZ AS WE WE JUST
TRANSPORT WATER DROPLETS ONSHORE. WE MAINTAIN AN ONSHORE FLOW INTO
TUESDAY...BUT IT LOOKS LIKE FORCING WILL BE LIMITED TO
UPSLOPE...SO THINKING MORE IN THE WAY OF SHSN/SHRA/VERY LIGHT SNOW
INLAND...WITH JUST CLOUDS ON THE COAST. SHOULD SEE TEMPS ON TUE
WARM INTO THE UPPER 30S TO MID 40S.

THE MAIN EVENT REMAINS THE IMPRESSIVE 500 MB TROUGH THAT DEVELOPS
OVER THE CENTRAL CONUS MID WEEK...NOT SO MUCH IN THAT IT IS VERY
DEEP...BUT MORE ITS AMPLITUDE AS IT EXTENDS FROM N OF THE GREAT
LAKES SWD INTO THE GULF OF MEX....AND THEN TILTS VERY NEG AND
LIFTS POLEWARD WED NIGHT AND THU. NOT SURE HOW MUCH AN EFFECT
CONVECTIVE SCALING ISSUES ARE HAVING ON THE MODELS...BUT IT MAY BE
HAVING SOME EFFECT ON THE FORECAST DETAILS...BUT PROB NOT THE
GENERALITIES OF THE FORECAST. HOWEVER...00Z EURO AND GFS BOTH SHOW
A WEAKER SFC LOW IN THE VCNITY OF THE GRT LAKES AND ST LAWRENCE
VLY /ALTHOUGH IT DOES INTENSIFY FURTHER N AND E THAN PREV MODEL
RUNS. STILL...AS THAT WAVE LIFTS NWD WILL SEE TRIPLE POINT DEVELOP
OVER THE MID ATLANTIC WED EVE...AND LIFT NNE INTO THE CWA BY THU
MORNING. THIS WILL CREATE A DEEP SOUTHERLY FLOW WHICH WILL CONNECT
WITH GULF MOISTURE...ALLOWING FOR SIGNIFICANT RAINFALL...FROM
LATE IN THE DAY WED...INTO EARLY THU MORNING. QPF LOOKS TO RUN
AROUND 2-3 INCHES IN MANY SPOTS...BUT S-SE UPSLOPE AREAS OF THE
FOOTHILLS AND MTNS COULD SEE AN INCH OR TWO MORE...SO THE THREAT
OF BOTH FLASH AND MAINSTEM FLOODING IS A CONCERN...ESPECIALLY
SINCE THIS WILL BE COMBINE WITH SIGNIFICANT SNOWMELT AS HIGHS
RISE WELL INTO THE 40S WED..AND WILL LKLY STAY THERE WED NIGHT
INTO THU.

THERE IS STILL THE POTENTIAL FOR SOME STRONG GUSTS...BUT GIVEN
WEAKER SYSTEM...THE WINDOW FOR OPPORTUNITY WILL BE LIMITED TO A
FE HOURS AHEAD OF THE TRIPLE POINT PASSAGE...WHICH LOOKS TO BE WED
EVE...AT LEAST FOR NOW. WITH ALL THAT SAID...WE ARE STILL DEALING
WITH DAYS 4 AND 5 OF THE FORECAST...WITH THE POTENTIAL FRO SOME
DEEP CONVECTION IN THE BASE OF THE TROUGH...SO FORECAST COULD
CHANGE...BUT BOTH EURO AND GFS PICKED UP THE SIGNALS OF THIS
SYSTEM EARLY...AND HAVE BEEN CONSISTENT ON THE WHOLE SO FAR.

CHRISTMAS DAY WILL SEE RAIN ENDING FROM SW TO NE DURING THE
MORNING...WITH SOME PARTIAL CLEARING POSSIBLE IN THE
AFTERNOON...AND TEMPS IN THE 40S AGAIN. COOLER AIR WILL MOVE IN
FROM THE SW THU NIGHT. FRI AND SAT LOOK MOSTLY DRY /OTHER THAN
POSSIBLE UPSLOPE SHSN ON FRI/. HIGHS WILL CONTINUE TO RUN A FEW
DEGREES ABV NORMAL.

&&

.AVIATION /11Z SUNDAY THROUGH THURSDAY/...
SHORT TERM...MVFR TO IFR CEILINGS WILL REMAIN OVER THE REGION
THROUGH AT LEAST SUNDAY EVENING. CONDITIONS MAY IMPROVE A BIT
SUNDAY NIGHT AS THE ON SHORE FLOW DRIFTING MOISTURE INLAND WILL
GET SHUT OFF. CONDITIONS WILL NOT STAY UP LONG HOWEVER AS THE FLOW
WILL SWITCH BACK TO ON SHORE ON MONDAY BRINGING ANOTHER ROUND OF
MVFR TO IFR CEILINGS.

LONG TERM...POSSIBLE PERIODS OF MVFR TO IFR MONDAY NIGHT AS
INVERTED TROUGH MOVES INLAND. MVFR LIKELY TO HOLD TUESDAY INTO
TUESDAY NIGHT...LOWERING TO IFR LATE TUESDAY NIGHT INTO THURSDAY
MORNING IN RAIN...WITH INCREASING E-SE WINDS WEDNESDAY.

&&

.MARINE...
SHORT TERM...A FEW WIND GUSTS CONTINUE JUST BELOW 25 KTS THIS
AFTERNOON...WITH WAVES 4` OR LOWER...THEREFORE NO FLAGS IN THE
NEAR TERM. WINDS SHOULD CONTINUE TO SLOWLY DECREASE TONIGHT INTO
TOMORROW FROM THE NORTHEAST.

LONG TERM...HIGH PRESSURE WITH LIGHT AND FAIRLY CALM SEAS WILL
PERSIST THROUGH THE PERIOD AND NO FLAGS ARE EXPECTED.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.

&&

$$
KISTNER/CEMPA



000
FXUS61 KGYX 211116
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
616 AM EST SUN DEC 21 2014

.SYNOPSIS...
HIGH PRESSURE BUILDS OVER NORTHERN MAINE SUNDAY...ALLOWING THE
FLOW TO TURN ONSHORE. A WEAK WEATHER DISTURBANCE MAY TRIGGER SOME
FLURRIES OR LIGHT SNOW OVER SOUTHERN REGIONS RIGHT THROUGH MONDAY.
A SIGNIFICANT LOW PRESSURE SYSTEM SYSTEM WILL GRADUALLY ORGANIZE
WEDNESDAY...BEFORE MOVING OVER THE GREAT LAKES. THIS COULD BRING
WINDY CONDITIONS AND THE POTENTIAL FOR HEAVY RAIN AROUND CHRISTMAS
EVE INTO EARLY CHRISTMAS MORNING.

&&

.NEAR TERM /THROUGH TONIGHT/...
615 AM UPDATE...JUST MADE SOME MINOR UPDATES TO SKY AND
TEMPERATURES BASED ON CURRENT OBS AND TRENDS...AS STRATUS REMAINS
ENTRENCHED ACROSS THE REGION.

PREVIOUS DISCUSSION...
LOW STRATUS BLANKETS THE CWFA AS A SURFACE HIGH PRESSURE IN
SOUTHERN QUEBEC IS HELPING TO KEEP MOISTURE TRAPPED IN THE LOW
LEVELS. A WEAK SHORTWAVE THAT IS PASSING OVER THE SOUTHERN NEW
ENGLAND THIS MORNING AND THIS MAY HELP KICK OFF SOME LIGHT SNOW
ACROSS THE FAR SOUTHERN AREAS OF NEW HAMPSHIRE AND PARTS OF
SOUTHWEST MAINE...AS ON SHORE FLOW SUPPLIES THE LOW LEVEL MOISTURE
THE LIFT FROM THIS WEAK SHORT MAY BE JUST ENOUGH TO PRODUCE SNOW
SHOWERS HEAVY ENOUGH TO ACCUMULATE IN SOME AREAS. AS THIS WEAK
WAVE MOVES EAST OUR FLOW...ALTHOUGH VERY WEAK...WILL TURN TO
NORTHWESTERLY AND THIS MAY BE ENOUGH TO START CLEARING OUT SOME OF
THE LOW STRATUS SUNDAY NIGHT.

&&

.SHORT TERM /MONDAY/...
FLOW WILL SWITCH BACK TO ON SHORE BY NOON ON MONDAY AND THIS WILL
BRING LIGHT OCEAN EFFECT SNOW OR MAYBE EVEN SOME LIGHT RAIN OR
EVEN FREEZING DRIZZLE INTO THE INTERIOR AS TEMPERATURES WILL HOVER
CLOSE TO FREEZING AS YOU GET AWAY FROM THE COAST.

&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
MODELS CONTINUE TO TREND TOWARD UPSTREAM AND DOWNSTREAM
BLOCKING...WITH AN EVENTUAL RETURN TO A +PNA PATTERN AT
500MB...WHICH WOULD SIGNAL COOLING LATE IN THE PERIOD. HOWEVER
ALL THE ACTION WILL BE IN DAYS 3 TO 5 AS THE UPSTREAM DEVELOPS AND
SENDS WAVES INTO TROUGH OVER CENTRAL CONUS...AMPLIFYING THE 500
MB FLOW.

INITIALLY...WILL BE DEALING WITH SMALLER SCALE FEATURE AS
INVERTED TROUGH OVER THE GULF OF ME WORK ITS WAY ONSHORE MON NIGHT
AND WEAKENS. MAY BE ENOUGH DYNAMIC FORCING FOR ICE CRYSTALS
INITIALLY...SO RAIN OR SNOW SHOWERS MOVE ONSHORE AND INLAND DURING
THE EVENING...BUT COULD SEE IT TURN TO DZ/FZDZ AS WE WE JUST
TRANSPORT WATER DROPLETS ONSHORE. WE MAINTAIN AN ONSHORE FLOW INTO
TUESDAY...BUT IT LOOKS LIKE FORCING WILL BE LIMITED TO
UPSLOPE...SO THINKING MORE IN THE WAY OF SHSN/SHRA/VERY LIGHT SNOW
INLAND...WITH JUST CLOUDS ON THE COAST. SHOULD SEE TEMPS ON TUE
WARM INTO THE UPPER 30S TO MID 40S.

THE MAIN EVENT REMAINS THE IMPRESSIVE 500 MB TROUGH THAT DEVELOPS
OVER THE CENTRAL CONUS MID WEEK...NOT SO MUCH IN THAT IT IS VERY
DEEP...BUT MORE ITS AMPLITUDE AS IT EXTENDS FROM N OF THE GREAT
LAKES SWD INTO THE GULF OF MEX....AND THEN TILTS VERY NEG AND
LIFTS POLEWARD WED NIGHT AND THU. NOT SURE HOW MUCH AN EFFECT
CONVECTIVE SCALING ISSUES ARE HAVING ON THE MODELS...BUT IT MAY BE
HAVING SOME EFFECT ON THE FORECAST DETAILS...BUT PROB NOT THE
GENERALITIES OF THE FORECAST. HOWEVER...00Z EURO AND GFS BOTH SHOW
A WEAKER SFC LOW IN THE VCNITY OF THE GRT LAKES AND ST LAWRENCE
VLY /ALTHOUGH IT DOES INTENSIFY FURTHER N AND E THAN PREV MODEL
RUNS. STILL...AS THAT WAVE LIFTS NWD WILL SEE TRIPLE POINT DEVELOP
OVER THE MID ATLANTIC WED EVE...AND LIFT NNE INTO THE CWA BY THU
MORNING. THIS WILL CREATE A DEEP SOUTHERLY FLOW WHICH WILL CONNECT
WITH GULF MOISTURE...ALLOWING FOR SIGNIFICANT RAINFALL...FROM
LATE IN THE DAY WED...INTO EARLY THU MORNING. QPF LOOKS TO RUN
AROUND 2-3 INCHES IN MANY SPOTS...BUT S-SE UPSLOPE AREAS OF THE
FOOTHILLS AND MTNS COULD SEE AN INCH OR TWO MORE...SO THE THREAT
OF BOTH FLASH AND MAINSTEM FLOODING IS A CONCERN...ESPECIALLY
SINCE THIS WILL BE COMBINE WITH SIGNIFICANT SNOWMELT AS HIGHS
RISE WELL INTO THE 40S WED..AND WILL LKLY STAY THERE WED NIGHT
INTO THU.

THERE IS STILL THE POTENTIAL FOR SOME STRONG GUSTS...BUT GIVEN
WEAKER SYSTEM...THE WINDOW FOR OPPORTUNITY WILL BE LIMITED TO A
FE HOURS AHEAD OF THE TRIPLE POINT PASSAGE...WHICH LOOKS TO BE WED
EVE...AT LEAST FOR NOW. WITH ALL THAT SAID...WE ARE STILL DEALING
WITH DAYS 4 AND 5 OF THE FORECAST...WITH THE POTENTIAL FRO SOME
DEEP CONVECTION IN THE BASE OF THE TROUGH...SO FORECAST COULD
CHANGE...BUT BOTH EURO AND GFS PICKED UP THE SIGNALS OF THIS
SYSTEM EARLY...AND HAVE BEEN CONSISTENT ON THE WHOLE SO FAR.

CHRISTMAS DAY WILL SEE RAIN ENDING FROM SW TO NE DURING THE
MORNING...WITH SOME PARTIAL CLEARING POSSIBLE IN THE
AFTERNOON...AND TEMPS IN THE 40S AGAIN. COOLER AIR WILL MOVE IN
FROM THE SW THU NIGHT. FRI AND SAT LOOK MOSTLY DRY /OTHER THAN
POSSIBLE UPSLOPE SHSN ON FRI/. HIGHS WILL CONTINUE TO RUN A FEW
DEGREES ABV NORMAL.

&&

.AVIATION /11Z SUNDAY THROUGH THURSDAY/...
SHORT TERM...MVFR TO IFR CEILINGS WILL REMAIN OVER THE REGION
THROUGH AT LEAST SUNDAY EVENING. CONDITIONS MAY IMPROVE A BIT
SUNDAY NIGHT AS THE ON SHORE FLOW DRIFTING MOISTURE INLAND WILL
GET SHUT OFF. CONDITIONS WILL NOT STAY UP LONG HOWEVER AS THE FLOW
WILL SWITCH BACK TO ON SHORE ON MONDAY BRINGING ANOTHER ROUND OF
MVFR TO IFR CEILINGS.

LONG TERM...POSSIBLE PERIODS OF MVFR TO IFR MONDAY NIGHT AS
INVERTED TROUGH MOVES INLAND. MVFR LIKELY TO HOLD TUESDAY INTO
TUESDAY NIGHT...LOWERING TO IFR LATE TUESDAY NIGHT INTO THURSDAY
MORNING IN RAIN...WITH INCREASING E-SE WINDS WEDNESDAY.

&&

.MARINE...
SHORT TERM...A FEW WIND GUSTS CONTINUE JUST BELOW 25 KTS THIS
AFTERNOON...WITH WAVES 4` OR LOWER...THEREFORE NO FLAGS IN THE
NEAR TERM. WINDS SHOULD CONTINUE TO SLOWLY DECREASE TONIGHT INTO
TOMORROW FROM THE NORTHEAST.

LONG TERM...HIGH PRESSURE WITH LIGHT AND FAIRLY CALM SEAS WILL
PERSIST THROUGH THE PERIOD AND NO FLAGS ARE EXPECTED.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.

&&

$$
KISTNER/CEMPA




000
FXUS61 KBOX 210916
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
416 AM EST SUN DEC 21 2014

.SYNOPSIS...
AN AREA OF SNOW SHOWERS WILL AFFECT AREAS MAINLY SOUTH OF THE MA
TURNPIKE THIS MORNING...EXCEPT IT WILL BE MILD ENOUGH FOR RAIN
SHOWERS ACROSS THE FAR SOUTHEAST NEW ENGLAND COAST. WEAK LOW
PRESSURE WILL PASS SOUTH OF NEW ENGLAND BRINGING ANOTHER PERIOD OF
PRECIPITATION MONDAY NIGHT AND TUESDAY. A MUCH STRONGER STORM
PASSING WEST OF NEW ENGLAND WILL BRING HEAVY RAINFALL...GUSTY
WINDS AND COASTAL FLOODING CONCERNS TO THE REGION WEDNESDAY AND
WEDNESDAY NIGHT. DRY BUT VERY WINDY CONDITIONS FOLLOW FOR
CHRISTMAS DAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...

4 AM UPDATE...

APPROACHING SHORTWAVE HAS ALLOWED AN AREA LIGHT SNOW SHOWERS TO
EXPAND SOUTH OF THE MA TURNPIKE VERY EARLY THIS MORNING...BUT A FEW
SNOW SHOWERS DID EXTEND INTO NORTHERN MA.  RADAR IMAGERY ACTUALLY
OVER SHOOTING SOME OF THE ACTIVITY ACROSS NORTHERN CT...BASED ON
OBSERVATIONS.  THE RAIN/SNOW LINE RUNS ROUGHLY FROM NEWPORT...TO
TAUNTON AND JUST NORTH OF MARSHFIELD.  OVERALL...DO NOT EXPECT MUCH
CHANGE IN THE RAIN/SNOW LINE THIS MORNING BASED ON THERMAL PROFILES
AND POSITIONING OF THE COASTAL FRONT.

MAIN UNCERTAINTY IS JUST HOW MUCH SNOW OCCURS THIS MORNING WITH THE
SHORTWAVE MOVING ACROSS CT.  GIVEN THE TRACK OF THE SHORTWAVE...BEST
FORCING WILL BE LOCATED SOUTH OF THE MA TURNPIKE AND ESPECIALLY
ACROSS NORTHERN CT/RI.  WE WILL FORECAST 1 TO 2 INCHES OF SNOW
ACROSS THIS REGION...BUT A FEW ISOLATED 3 INCH AMOUNTS CAN NOT BE
RULED OUT. MEANWHILE...AREAS NORTH OF THE MA TURNPIKE WILL BE
REMOVED FROM THE BEST FORCING...BUT STILL SEE SOME SCATTERED
SHOWERS.  ACCUMS IN THIS AREA LIKELY TO BE A DUSTING TO LESS THAN AN
INCH.

ALSO...SOME OF THE PRECIPITATION CURRENTLY ACROSS SOUTHEAST MA IS
BEING ENHANCED FROM THE COASTAL FRONT.  A LOT OF THIS PRECIP WILL
BE IN THE FORM OF RAIN SHOWERS ACROSS PLYMOUTH AND EVEN INTO
PORTIONS OF BRISTOL COUNTY...POINTS SOUTH AND EAST.  HOWEVER...AT
LEAST THE SLIGHTLY HIGHER TERRAIN OF SOUTHEAST MA SHOULD SEE SNOW
SHOWERS.  WILL HAVE TO KEEP A CLOSE EYE ON IF COASTAL FRONT SHIFTS
SLIGHTLY THIS MORNING.  IT COULD MEAN THE DIFFERENCE BETWEEN AN AREA
GETTING MAINLY RAIN SHOWERS OR PERHAPS AN INCH OR SO OF SNOW.
OVERALL...DO NOT EXPECT THE COASTAL FRONT TO MOVE TOO MUCH THIS
MORNING...BUT JUST A FEW MILES CAN MAKE DIFFERENCE FOR A
PARTICULARLY NEIGHBORHOOD.

BULK OF PRECIPITATION WILL BE THIS MORNING WITH THE SHORTWAVE.
HOWEVER...ENOUGH LOW LEVEL MOISTURE/WEAK LIFT WILL REMAIN THIS
AFTERNOON FOR AT LEAST THIS RISK OF SCATTERED PRECIPITATION AND WILL
MAINTAIN SOME POPS.  HIGH TEMPS MAINLY IN THE 30S.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...

TONIGHT...

A RATHER CLOUDY AND RAW NIGHT ACROSS SOUTHERN NEW ENGLAND.  WHILE
THERE IS NOT A SIGNIFICANT SHORTWAVE TO TRIGGER A LOT OF
PRECIPITATION...PLENTY OF LOW LEVEL MOISTURE/WEAK SHALLOW LIFT
REMAINS.  THIS MAY BE ENOUGH TO RESULT IN A FEW RAIN/SNOW SHOWER
FROM TIME TO TIME.  PTYPE...WOULD BE MAINLY SNOW SHOWERS EXCEPT TO
THE SOUTHEAST OF A NEWPORT...TO TAUNTON...TO JUST NORTH OF
MARSHFIELD LINE.  AGAIN...MUCH OF THE NIGHT WILL PROBABLY END UP
DRY...BUT JUST THE RISK FOR A FEW RAIN/SNOW SHOWERS.

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...

HIGHLIGHTS...

* WEAK SHORTWAVE ON MON NIGHT/TUESDAY COULD BRING WINTRY
  MIX/FREEZING RAIN TO THE INTERIOR
* ANOMALOUS SYSTEM ACROSS THE GREAT LAKES WILL BRING HEAVY
  RAIN...GUSTY WINDS AND COASTAL FLOODING CONCERNS AROUND CHRISTMAS
  EVE
* BLUSTERY BUT AIRMASS WILL BE DRYING OUT ON CHRISTMAS DAY

OVERVIEW...

THE MODELS AND ENSEMBLES OFFER A REASONABLY SIMILAR AND PREDICTABLE
LARGER SCALE MID TO UPPER LEVEL PATTERN EVOLUTION FOR MUCH OF THE
UPCOMING WEEK. THIS ACTIVE FLOW REGIME DEVELOPS SEVERAL MID-UPPER
LEVEL TROUGH AND ASSOCIATED/UNSETTLING LEAD SURFACE LOW/FRONTAL
SYSTEMS AND PCPN SWATHS PROGRESS STEADILY ACROSS THE LOWER 48. THE
FIRST AMPLIFIED/DEEP LEAD SYSTEM WORKS ACROSS THE ERN/NERN US INTO
ERN CANADA CHRISTMAS EVE INTO CHRISTMAS ALLOWING FOR A MOIST/WARMED
AIRMASS IN ADVANCE OF FRONTAL APPROACH WITH HEAVIEST LEAD QPF
POTENTIAL OVER NEW ENGLAND. BIGGEST QUESTION IS THE EVOLUTION OF THE
SECONDARY LOW PRESSURE SYSTEM. 00Z GUIDANCE HAS BACKED OFF ON THE
STRENGTH OF THE LOW AND IS HAVING ISSUES ON HOW TO HANDLE ITS
EVOLUTION. THE EC AND GFS HAVE SLOWED DOWN THE SYSTEM SLIGHTLY WITH
THE EC HAVING MORE OF A NEGATIVE TROUGH VS THE GFS. BELIEVE THE
UKMET IS A GOOD COMPROMISE AT IS WAS THE FIRST DETERMINISTIC
GUIDANCE ON TAMPERING DOWN THE FIRST MAIN LOW...WHILE THE CMC IS OUT
TO LUNCH. REGARDLESS THIS IS A VERY ANOMALOUS SYSTEM THAT IS ABOUT 4
STANDARD DEVIATIONS AWAY.

A SECONDARY SYSTEM DEEPENS ACROSS THE FOUR CORNERS ON FRIDAY AND
WITH THE STUBBORN TROUGH OVER THE CENTRAL U.S...IT WILL PUSH A
SYSTEM TOWARDS SOUTHERN NEW ENGLAND BY SUNDAY. THIS SYSTEM MAY
SUPPORT A MODEST SWATH OF OVERRUNNING SNOW OVER SOUTHERN NEW
ENGLAND.

DETAILS...

MONDAY INTO TUESDAY...MODERATE CONFIDENCE.

A WEAK WAVE OF LOW PRESSURE DEVELOPS ALONG THE SOUTHEAST COAST
MONDAY...AND WILL BE ON A DEVELOPING WARM FRONTAL BOUNDARY. THIS LOW
REMAINS WEAK AS THE WARM FRONT MOVES SLOWLY NORTH MONDAY NIGHT INTO
TUESDAY. APPEARS THAT THERE IS DECENT WARM ADVECTION AHEAD OF THIS
WAVE. SEVERAL HI-RES GUIDANCE MODELS SHOW THAT THERE IS THE
POTENTIAL FOR COLD AIR DAMMING ACROSS THE INTERIOR INTO TUESDAY.
BIGGEST QUESTION WILL BE IS THERE ENOUGH MOISTURE FOR PRECIP DURING
THIS TIME FRAME. DUE TO A STRENGTHENING LLJ PROVIDING A GOOD SOURCE OF
LIFT ANTICIPATE PRECIP TO DEVELOP AND OVERSPREAD ACROSS SOUTHERN NEW
ENGLAND. IF THIS PLAYS OUT WITH COLD AIR DAMMING AND WARM AIR
ADVECTION...THEN WE COULD SEE FREEZING RAIN/DRIZZLE ACROSS THE I-91
CORRIDOR LATE MONDAY INTO TUESDAY MORNING. DURING THE DAY ON
TUESDAY...GOOD AMOUNT OF WARM AIR WILL PUSH SURFACE TEMPS ABOVE
FREEZING BY THE LATE MORNING ALLOWING FOR ANY PRECIP TO BE MORE OF
THE LIQUID VARIETY AHEAD OF THE CHRISTMAS EVE STORM. HOWEVER
GUIDANCE IS ALWAYS TOO FAST IN SCOURING TEMPS OUT ESP ACROSS THE CT
VALLEY SO WE WILL NEED TO MONITOR THIS CLOSELY...ESP DUE TO LIGHT
WINDS AND THE HIGH IN EASTERN CANADA. A WINTER WX ADVISORY MAY BE
NEEDED FOR THE LIGHT ICING POTENTIAL.

WE COULD ALSO SEE SOME MINOR COASTAL FLOODING CONCERNS ON TUESDAY. SEE
BELOW FOR MORE DETAILS.

WEDNESDAY INTO THURSDAY...HIGH CONFIDENCE IN SYSTEM LOW CONFIDENCE
ON DETAILS.

ANOMALOUS SYSTEM WILL STRENGTHEN OVER THE GREAT LAKES TUESDAY INTO
WEDNESDAY. A SECONDARY SHORTWAVE WILL ROUND THE DEEP TROUGH AND
DEVELOP A SECONDARY LOW PRESSURE ALONG THE COLD FRONT. THIS
SECONDARY LOW WILL STRENGTHEN AND PASS WEST OF SOUTHERN NEW ENGLAND.
THIS SYSTEM WILL CONTINUE TO DEEPEN AS IT MOVES TOWARDS EASTERN
CANADA SWINGING A COLD FRONT ACROSS THE NORTHEAST.

STRONG SOUTHERLY JET OUT AHEAD OF THE FRONT WITH A GULF MOISTURE
CONNECTION WILL IMPACT SOUTHERN NEW ENGLAND ON CHRISTMAS EVE. THIS
STRONG JET WILL YIELD FOR PCPN IN THE LIQUID VARIETY.  PW ANOMALIES
ARE BETWEEN +4 TO +5 STANDARD DEVIATIONS ABOVE NORMAL WHICH IS QUITE
ANOMALOUS FOR THIS TIME OF YEAR. IN FACT CURRENT PWATS ARE PROGGED
ABOVE 1.6 INCHES WITH MODEL QPF OVER 2 INCHES...AT THE VERY LEAST
COULD SEE URBAN AND POOR DRAINAGE FLOODING. LATEST EC EVEN SHOWS
OVER 2.5 INCHES OF QPF...AND WITH THE TROPICAL CONNECTION AND STRONG
SOUTHERLY FLOW COULD SEE HIGHER AMOUNTS DUE TO TOPOGRAPHY
ENHANCEMENTS. RAINFALL RECORDS MAY FALL IF EVERYTHING FALLS INTO
PLACE.

AHEAD OF THE FRONT...SOUTHERN NEW ENGLAND WILL WARM SECTOR WED INTO
THUR MORNING ALLOWING FOR TEMPERATURES TO BE WELL ABOVE AVERAGE. IN
FACT WE MAY BE CLOSE AT BREAKING RECORD HIGH TEMPS IF TEMPS WARM TO
60F OR ABOVE ON CHRISTMAS EVE. SINCE WE WILL BE IN THE WARM
SECTOR...AND SHOWALTERS CLOSE TO ZERO...ISOLATED THUNDER IS STILL
POSSIBLE.

STRONG LOW LEVEL WINDS WILL ALSO BE A CONCERN ESPECIALLY WEDNESDAY
NIGHT. THE ECMWF SHOWS EAST-SOUTHEAST WINDS 30-40 KNOTS ON WEDNESDAY
INCREASING TO 60-75 KNOTS BY WEDNESDAY NIGHT. STRONG DOWNPOURS MAY
OVERCOME THE LOW LEVEL INVERSION AND BRING STRONG GUSTS OF AT LEAST
30-40 KNOTS ESPECIALLY ALONG THE SOUTH COAST. A WIND ADVISORY MAY BE
NEEDED IN SOME AREAS.

CHRISTMAS DAY...MODERATE CONFIDENCE.

AS THE COLD FRONT PASSES THROUGH EARLY CHRISTMAS DAY...THE WEST
WINDS WILL HELP DRY THE AIRMASS ALLOWING FOR PARTLY SUNNY SKIES.
STRONG CAA ON THURSDAY WILL ALLOW DESCENT MIXING. WINDS IN THE SFC-
850 MB LAYER WILL BE 30-40 KNOTS AND POSSIBLY A LITTLE
HIGHER...WHICH WOULD REQUIRE A WIND ADVISORY FOR MUCH OF THE AREA.

FRIDAY-SUNDAY...LOWER CONFIDENCE

WEAK HIGH PRESSURE BUILDS OVER THE AREA FRIDAY INTO SATURDAY. THE
NEXT SHORTWAVE APPROACHES LATE SATURDAY INTO SUNDAY AND SHOULD BRING
INCREASING CLOUDS FROM WEST TO EAST ALONG WITH A CHANCE OF RAIN OR
SNOW SHOWERS MAINLY IN THE AFTERNOON AND AT NIGHT.

&&

.AVIATION /09Z SUNDAY THROUGH THURSDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /TODAY AND TONIGHT/...

TODAY AND TONIGHT...MODERATE CONFIDENCE.  MAINLY MVFR CONDITIONS
SOUTH OF THE MA TURNPIKE WITH BORDERLINE VFR TO MARGINAL MVFR CIGS
NORTH OF THE PIKE THROUGH TONIGHT.  AN AREA OF SNOW SHOWERS WILL
EXPAND MAINLY ACROSS AREAS SOUTH OF THE PIKE THIS MORNING...BUT A
FEW SNOW SHOWERS WILL STILL AFFECT NORTHERN MA.  VSBYS/CIGS MAY
BRIEFLY DROP TO IFR LEVELS IN NORTHERN CT/RI/SE MA.  PTYPE WILL BE
RAIN SHOWERS ACROSS MOST OF PLYMOUTH COUNTY AND ONTO THE
CAPE/ISLANDS WITH SNOW SHOWERS NORTH AND WEST.  BULK OF PRECIP THIS
MORNING...BUT A FEW LINGERING RAIN/SNOW SHOWERS STILL POSSIBLE THIS
AFTERNOON AND EVENING.

KBOS TERMINAL...MODERATE CONFIDENCE.  A FEW SNOW SHOWERS POSSIBLE
THIS MORNING BUT BULK OF ACTIVITY SHOULD BE SOUTH OF THE TERMINAL.

KBDL TERMINAL...MODERATE CONFIDENCE.  PERIOD OF SNOW SHOWERS THIS
MORNING MAY DROP AN INCH OR TWO OF SNOW.  MVFR CONDITIONS DOMINATE
TODAY....BUT A BRIEF PERIOD OF IFR CONDITIONS ARE POSSIBLE THIS
MORNING IN SNOW SHOWERS.

OUTLOOK...MONDAY THROUGH THURSDAY...MODERATE CONFIDENCE.

MONDAY...MVFR CIGS CONTINUE IN RI/EASTERN MASS IN MARINE EAST FLOW.
VFR IN THE WEST.

TUESDAY...VFR WITH SCATTERED MVFR IN ANY RAIN/SNOW SHOWERS.

WEDNESDAY...CONDITIONS LOWERING TO IFR IN RAIN/HEAVY RAIN. ISOLATED
THUNDERSTORMS POSSIBLE ESPECIALLY WEDNESDAY NIGHT. EAST-SOUTHEAST
SURFACE WINDS MAY GUST TO 35-45 KNOTS. WINDS AT 2000 FEET AGL WILL
REACH 50-60 KNOTS WEDNESDAY AFTERNOON AND EARLY NIGHT CREATING LOW
LEVEL WIND SHEAR CONCERNS.

CHRISTMAS DAY...WEST WIND GUSTING 30-40 KNOTS. CONDITIONS IMPROVING
TO VFR AS THE WIND BRINGS IN COOLER DRIER AIR.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /TODAY AND TONIGHT/...HIGH CONFIDENCE.

HIGH PRESSURE ACROSS QUEBEC WILL RESULT IN NORTHEAST WINDS ACROSS
THE WATERS THAT WILL GUST TO BETWEEN 15 AND 20 KNOTS.  THIS WILL
RESULT IN 2 TO 4 FOOT SEAS.  HOWEVER...NO HEADLINES PLANNED AS
CONDITIONS SHOULD REMAIN BELOW SMALL CRAFT ADVISORY THRESHOLDS.

OUTLOOK...MONDAY THROUGH THURSDAY...MODERATE CONFIDENCE

MONDAY...EAST TO NORTHEAST WINDS GUSTING AROUND 15 KNOTS OR LESS.
SEAS WILL HOLD AROUND 3-4 FEET...MAY INCREASE TO 5FT IN NORTHEAST
FLOW AS GUIDANCE MAY BE UNDERDONE.

TUESDAY... INCREASING EAST WINDS WITH FREQUENT GUSTS 25 TO 30 KNOTS.
SEAS WILL BUILD TO 5-6 FEET ON THE EXPOSED WATERS.  A SMALL CRAFT
ADVISORY MAY BE NEEDED.

WEDNESDAY...RAIN WILL BE HEAVY AT TIMES PRODUCING POOR VISIBILITY.
INCREASING SOUTHEAST WINDS 20-25 SUSTAINED AND 40 KNOT GUSTS.  WINDS
SHOULD SHIFT TO SOUTH WEDNESDAY NIGHT AND SOUTHWEST TOWARD THURSDAY
MORNING. RAIN WILL TAPER OFF WITH THE WIND SHIFT TO SOUTHWEST. SEAS
WILL CONTINUE TO BUILD WITH 7-11 FEET HEIGHTS ON THE EXPOSED WATERS.
A GALE WARNING WILL BE NEEDED...WITH A LOW PROB OF A FEW STORM FORCE
GUSTS ACROSS THE EASTERN OUTER WATERS.

CHRISTMAS DAY... WEST SOUTHWEST WINDS WILL CONTINUE TO GUST 35-40
KNOTS...SO A CONTINUED GALE WARNING MAY BE NEEDED. SEAS OF 7-15 FEET
ARE POSSIBLE ON THE EXPOSED WATERS...AND 5 FEET IS POSSIBLE ON SOME
OF THE NEARSHORE WATERS.

&&

.TIDES/COASTAL FLOODING...

HIGH ASTRONOMICAL TIDES WILL OCCUR TUESDAY THROUGH THURSDAY. BREAKING
IT DOWN...ON TUESDAY HIGH TIDE AT BOSTON WILL BE 11.6 FT. THERE WILL
BE ONSHORE FLOW DURING THIS HIGH TIDE ALLOWING FOR MINOR SPLASHOVER.
IF WIND GUSTS INCREASE THEN COULD POSSIBLE SEE MINOR COASTAL
FLOODING.

ON WEDNESDAY...WINDS WILL SWITCH TO A MORE SOUTHEASTERLY FLOW DURING
THE DAY AND INCREASE QUICKLY FROM APPROACHING SYSTEM AND DECENT
PRESSURE FALLS. WEDNESDAY AFTERNOON HIGH TIDE IN BOSTON IS 11.7 FT
AND WITH ANY STRENGTH ON THE EASTERLY WIND FLOW WILL PUSH THE TIDE
OVER. RIGHT NOW BELIEVE MINOR COASTAL FLOODING IS POSSIBLE ALONG THE
EAST COASTLINE.

WEDNESDAY EVENING...THE WIND GOES IN A MORE SOUTHERLY DIRECTION AND
THE TIDE WILL BE INCREASE ACROSS THE SOUTH COAST. HIGH TIDE IN
PROVIDENCE WILL BE 5.2 FT. 925 MB LLJ STRENGTHENS TO 50-60 KTS WHICH
COULD PUSH A DECENT SURGE UP ALONG THE SOUTH COAST DURING THE TIME
OF HIGH TIDE. THINKING THAT MINOR COASTAL FLOODING COULD OCCUR BUT
CANNOT RULE OUT MODERATE ALONG THE SOUTH COAST...ESP IF LLJ
STRENGTHENS EVEN MORE.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...FRANK/DUNTEN
NEAR TERM...FRANK
SHORT TERM...FRANK
LONG TERM...DUNTEN
AVIATION...FRANK/DUNTEN
MARINE...FRANK/DUNTEN
TIDES/COASTAL FLOODING...DUNTEN




000
FXUS61 KBOX 210916
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
416 AM EST SUN DEC 21 2014

.SYNOPSIS...
AN AREA OF SNOW SHOWERS WILL AFFECT AREAS MAINLY SOUTH OF THE MA
TURNPIKE THIS MORNING...EXCEPT IT WILL BE MILD ENOUGH FOR RAIN
SHOWERS ACROSS THE FAR SOUTHEAST NEW ENGLAND COAST. WEAK LOW
PRESSURE WILL PASS SOUTH OF NEW ENGLAND BRINGING ANOTHER PERIOD OF
PRECIPITATION MONDAY NIGHT AND TUESDAY. A MUCH STRONGER STORM
PASSING WEST OF NEW ENGLAND WILL BRING HEAVY RAINFALL...GUSTY
WINDS AND COASTAL FLOODING CONCERNS TO THE REGION WEDNESDAY AND
WEDNESDAY NIGHT. DRY BUT VERY WINDY CONDITIONS FOLLOW FOR
CHRISTMAS DAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...

4 AM UPDATE...

APPROACHING SHORTWAVE HAS ALLOWED AN AREA LIGHT SNOW SHOWERS TO
EXPAND SOUTH OF THE MA TURNPIKE VERY EARLY THIS MORNING...BUT A FEW
SNOW SHOWERS DID EXTEND INTO NORTHERN MA.  RADAR IMAGERY ACTUALLY
OVER SHOOTING SOME OF THE ACTIVITY ACROSS NORTHERN CT...BASED ON
OBSERVATIONS.  THE RAIN/SNOW LINE RUNS ROUGHLY FROM NEWPORT...TO
TAUNTON AND JUST NORTH OF MARSHFIELD.  OVERALL...DO NOT EXPECT MUCH
CHANGE IN THE RAIN/SNOW LINE THIS MORNING BASED ON THERMAL PROFILES
AND POSITIONING OF THE COASTAL FRONT.

MAIN UNCERTAINTY IS JUST HOW MUCH SNOW OCCURS THIS MORNING WITH THE
SHORTWAVE MOVING ACROSS CT.  GIVEN THE TRACK OF THE SHORTWAVE...BEST
FORCING WILL BE LOCATED SOUTH OF THE MA TURNPIKE AND ESPECIALLY
ACROSS NORTHERN CT/RI.  WE WILL FORECAST 1 TO 2 INCHES OF SNOW
ACROSS THIS REGION...BUT A FEW ISOLATED 3 INCH AMOUNTS CAN NOT BE
RULED OUT. MEANWHILE...AREAS NORTH OF THE MA TURNPIKE WILL BE
REMOVED FROM THE BEST FORCING...BUT STILL SEE SOME SCATTERED
SHOWERS.  ACCUMS IN THIS AREA LIKELY TO BE A DUSTING TO LESS THAN AN
INCH.

ALSO...SOME OF THE PRECIPITATION CURRENTLY ACROSS SOUTHEAST MA IS
BEING ENHANCED FROM THE COASTAL FRONT.  A LOT OF THIS PRECIP WILL
BE IN THE FORM OF RAIN SHOWERS ACROSS PLYMOUTH AND EVEN INTO
PORTIONS OF BRISTOL COUNTY...POINTS SOUTH AND EAST.  HOWEVER...AT
LEAST THE SLIGHTLY HIGHER TERRAIN OF SOUTHEAST MA SHOULD SEE SNOW
SHOWERS.  WILL HAVE TO KEEP A CLOSE EYE ON IF COASTAL FRONT SHIFTS
SLIGHTLY THIS MORNING.  IT COULD MEAN THE DIFFERENCE BETWEEN AN AREA
GETTING MAINLY RAIN SHOWERS OR PERHAPS AN INCH OR SO OF SNOW.
OVERALL...DO NOT EXPECT THE COASTAL FRONT TO MOVE TOO MUCH THIS
MORNING...BUT JUST A FEW MILES CAN MAKE DIFFERENCE FOR A
PARTICULARLY NEIGHBORHOOD.

BULK OF PRECIPITATION WILL BE THIS MORNING WITH THE SHORTWAVE.
HOWEVER...ENOUGH LOW LEVEL MOISTURE/WEAK LIFT WILL REMAIN THIS
AFTERNOON FOR AT LEAST THIS RISK OF SCATTERED PRECIPITATION AND WILL
MAINTAIN SOME POPS.  HIGH TEMPS MAINLY IN THE 30S.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...

TONIGHT...

A RATHER CLOUDY AND RAW NIGHT ACROSS SOUTHERN NEW ENGLAND.  WHILE
THERE IS NOT A SIGNIFICANT SHORTWAVE TO TRIGGER A LOT OF
PRECIPITATION...PLENTY OF LOW LEVEL MOISTURE/WEAK SHALLOW LIFT
REMAINS.  THIS MAY BE ENOUGH TO RESULT IN A FEW RAIN/SNOW SHOWER
FROM TIME TO TIME.  PTYPE...WOULD BE MAINLY SNOW SHOWERS EXCEPT TO
THE SOUTHEAST OF A NEWPORT...TO TAUNTON...TO JUST NORTH OF
MARSHFIELD LINE.  AGAIN...MUCH OF THE NIGHT WILL PROBABLY END UP
DRY...BUT JUST THE RISK FOR A FEW RAIN/SNOW SHOWERS.

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...

HIGHLIGHTS...

* WEAK SHORTWAVE ON MON NIGHT/TUESDAY COULD BRING WINTRY
  MIX/FREEZING RAIN TO THE INTERIOR
* ANOMALOUS SYSTEM ACROSS THE GREAT LAKES WILL BRING HEAVY
  RAIN...GUSTY WINDS AND COASTAL FLOODING CONCERNS AROUND CHRISTMAS
  EVE
* BLUSTERY BUT AIRMASS WILL BE DRYING OUT ON CHRISTMAS DAY

OVERVIEW...

THE MODELS AND ENSEMBLES OFFER A REASONABLY SIMILAR AND PREDICTABLE
LARGER SCALE MID TO UPPER LEVEL PATTERN EVOLUTION FOR MUCH OF THE
UPCOMING WEEK. THIS ACTIVE FLOW REGIME DEVELOPS SEVERAL MID-UPPER
LEVEL TROUGH AND ASSOCIATED/UNSETTLING LEAD SURFACE LOW/FRONTAL
SYSTEMS AND PCPN SWATHS PROGRESS STEADILY ACROSS THE LOWER 48. THE
FIRST AMPLIFIED/DEEP LEAD SYSTEM WORKS ACROSS THE ERN/NERN US INTO
ERN CANADA CHRISTMAS EVE INTO CHRISTMAS ALLOWING FOR A MOIST/WARMED
AIRMASS IN ADVANCE OF FRONTAL APPROACH WITH HEAVIEST LEAD QPF
POTENTIAL OVER NEW ENGLAND. BIGGEST QUESTION IS THE EVOLUTION OF THE
SECONDARY LOW PRESSURE SYSTEM. 00Z GUIDANCE HAS BACKED OFF ON THE
STRENGTH OF THE LOW AND IS HAVING ISSUES ON HOW TO HANDLE ITS
EVOLUTION. THE EC AND GFS HAVE SLOWED DOWN THE SYSTEM SLIGHTLY WITH
THE EC HAVING MORE OF A NEGATIVE TROUGH VS THE GFS. BELIEVE THE
UKMET IS A GOOD COMPROMISE AT IS WAS THE FIRST DETERMINISTIC
GUIDANCE ON TAMPERING DOWN THE FIRST MAIN LOW...WHILE THE CMC IS OUT
TO LUNCH. REGARDLESS THIS IS A VERY ANOMALOUS SYSTEM THAT IS ABOUT 4
STANDARD DEVIATIONS AWAY.

A SECONDARY SYSTEM DEEPENS ACROSS THE FOUR CORNERS ON FRIDAY AND
WITH THE STUBBORN TROUGH OVER THE CENTRAL U.S...IT WILL PUSH A
SYSTEM TOWARDS SOUTHERN NEW ENGLAND BY SUNDAY. THIS SYSTEM MAY
SUPPORT A MODEST SWATH OF OVERRUNNING SNOW OVER SOUTHERN NEW
ENGLAND.

DETAILS...

MONDAY INTO TUESDAY...MODERATE CONFIDENCE.

A WEAK WAVE OF LOW PRESSURE DEVELOPS ALONG THE SOUTHEAST COAST
MONDAY...AND WILL BE ON A DEVELOPING WARM FRONTAL BOUNDARY. THIS LOW
REMAINS WEAK AS THE WARM FRONT MOVES SLOWLY NORTH MONDAY NIGHT INTO
TUESDAY. APPEARS THAT THERE IS DECENT WARM ADVECTION AHEAD OF THIS
WAVE. SEVERAL HI-RES GUIDANCE MODELS SHOW THAT THERE IS THE
POTENTIAL FOR COLD AIR DAMMING ACROSS THE INTERIOR INTO TUESDAY.
BIGGEST QUESTION WILL BE IS THERE ENOUGH MOISTURE FOR PRECIP DURING
THIS TIME FRAME. DUE TO A STRENGTHENING LLJ PROVIDING A GOOD SOURCE OF
LIFT ANTICIPATE PRECIP TO DEVELOP AND OVERSPREAD ACROSS SOUTHERN NEW
ENGLAND. IF THIS PLAYS OUT WITH COLD AIR DAMMING AND WARM AIR
ADVECTION...THEN WE COULD SEE FREEZING RAIN/DRIZZLE ACROSS THE I-91
CORRIDOR LATE MONDAY INTO TUESDAY MORNING. DURING THE DAY ON
TUESDAY...GOOD AMOUNT OF WARM AIR WILL PUSH SURFACE TEMPS ABOVE
FREEZING BY THE LATE MORNING ALLOWING FOR ANY PRECIP TO BE MORE OF
THE LIQUID VARIETY AHEAD OF THE CHRISTMAS EVE STORM. HOWEVER
GUIDANCE IS ALWAYS TOO FAST IN SCOURING TEMPS OUT ESP ACROSS THE CT
VALLEY SO WE WILL NEED TO MONITOR THIS CLOSELY...ESP DUE TO LIGHT
WINDS AND THE HIGH IN EASTERN CANADA. A WINTER WX ADVISORY MAY BE
NEEDED FOR THE LIGHT ICING POTENTIAL.

WE COULD ALSO SEE SOME MINOR COASTAL FLOODING CONCERNS ON TUESDAY. SEE
BELOW FOR MORE DETAILS.

WEDNESDAY INTO THURSDAY...HIGH CONFIDENCE IN SYSTEM LOW CONFIDENCE
ON DETAILS.

ANOMALOUS SYSTEM WILL STRENGTHEN OVER THE GREAT LAKES TUESDAY INTO
WEDNESDAY. A SECONDARY SHORTWAVE WILL ROUND THE DEEP TROUGH AND
DEVELOP A SECONDARY LOW PRESSURE ALONG THE COLD FRONT. THIS
SECONDARY LOW WILL STRENGTHEN AND PASS WEST OF SOUTHERN NEW ENGLAND.
THIS SYSTEM WILL CONTINUE TO DEEPEN AS IT MOVES TOWARDS EASTERN
CANADA SWINGING A COLD FRONT ACROSS THE NORTHEAST.

STRONG SOUTHERLY JET OUT AHEAD OF THE FRONT WITH A GULF MOISTURE
CONNECTION WILL IMPACT SOUTHERN NEW ENGLAND ON CHRISTMAS EVE. THIS
STRONG JET WILL YIELD FOR PCPN IN THE LIQUID VARIETY.  PW ANOMALIES
ARE BETWEEN +4 TO +5 STANDARD DEVIATIONS ABOVE NORMAL WHICH IS QUITE
ANOMALOUS FOR THIS TIME OF YEAR. IN FACT CURRENT PWATS ARE PROGGED
ABOVE 1.6 INCHES WITH MODEL QPF OVER 2 INCHES...AT THE VERY LEAST
COULD SEE URBAN AND POOR DRAINAGE FLOODING. LATEST EC EVEN SHOWS
OVER 2.5 INCHES OF QPF...AND WITH THE TROPICAL CONNECTION AND STRONG
SOUTHERLY FLOW COULD SEE HIGHER AMOUNTS DUE TO TOPOGRAPHY
ENHANCEMENTS. RAINFALL RECORDS MAY FALL IF EVERYTHING FALLS INTO
PLACE.

AHEAD OF THE FRONT...SOUTHERN NEW ENGLAND WILL WARM SECTOR WED INTO
THUR MORNING ALLOWING FOR TEMPERATURES TO BE WELL ABOVE AVERAGE. IN
FACT WE MAY BE CLOSE AT BREAKING RECORD HIGH TEMPS IF TEMPS WARM TO
60F OR ABOVE ON CHRISTMAS EVE. SINCE WE WILL BE IN THE WARM
SECTOR...AND SHOWALTERS CLOSE TO ZERO...ISOLATED THUNDER IS STILL
POSSIBLE.

STRONG LOW LEVEL WINDS WILL ALSO BE A CONCERN ESPECIALLY WEDNESDAY
NIGHT. THE ECMWF SHOWS EAST-SOUTHEAST WINDS 30-40 KNOTS ON WEDNESDAY
INCREASING TO 60-75 KNOTS BY WEDNESDAY NIGHT. STRONG DOWNPOURS MAY
OVERCOME THE LOW LEVEL INVERSION AND BRING STRONG GUSTS OF AT LEAST
30-40 KNOTS ESPECIALLY ALONG THE SOUTH COAST. A WIND ADVISORY MAY BE
NEEDED IN SOME AREAS.

CHRISTMAS DAY...MODERATE CONFIDENCE.

AS THE COLD FRONT PASSES THROUGH EARLY CHRISTMAS DAY...THE WEST
WINDS WILL HELP DRY THE AIRMASS ALLOWING FOR PARTLY SUNNY SKIES.
STRONG CAA ON THURSDAY WILL ALLOW DESCENT MIXING. WINDS IN THE SFC-
850 MB LAYER WILL BE 30-40 KNOTS AND POSSIBLY A LITTLE
HIGHER...WHICH WOULD REQUIRE A WIND ADVISORY FOR MUCH OF THE AREA.

FRIDAY-SUNDAY...LOWER CONFIDENCE

WEAK HIGH PRESSURE BUILDS OVER THE AREA FRIDAY INTO SATURDAY. THE
NEXT SHORTWAVE APPROACHES LATE SATURDAY INTO SUNDAY AND SHOULD BRING
INCREASING CLOUDS FROM WEST TO EAST ALONG WITH A CHANCE OF RAIN OR
SNOW SHOWERS MAINLY IN THE AFTERNOON AND AT NIGHT.

&&

.AVIATION /09Z SUNDAY THROUGH THURSDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /TODAY AND TONIGHT/...

TODAY AND TONIGHT...MODERATE CONFIDENCE.  MAINLY MVFR CONDITIONS
SOUTH OF THE MA TURNPIKE WITH BORDERLINE VFR TO MARGINAL MVFR CIGS
NORTH OF THE PIKE THROUGH TONIGHT.  AN AREA OF SNOW SHOWERS WILL
EXPAND MAINLY ACROSS AREAS SOUTH OF THE PIKE THIS MORNING...BUT A
FEW SNOW SHOWERS WILL STILL AFFECT NORTHERN MA.  VSBYS/CIGS MAY
BRIEFLY DROP TO IFR LEVELS IN NORTHERN CT/RI/SE MA.  PTYPE WILL BE
RAIN SHOWERS ACROSS MOST OF PLYMOUTH COUNTY AND ONTO THE
CAPE/ISLANDS WITH SNOW SHOWERS NORTH AND WEST.  BULK OF PRECIP THIS
MORNING...BUT A FEW LINGERING RAIN/SNOW SHOWERS STILL POSSIBLE THIS
AFTERNOON AND EVENING.

KBOS TERMINAL...MODERATE CONFIDENCE.  A FEW SNOW SHOWERS POSSIBLE
THIS MORNING BUT BULK OF ACTIVITY SHOULD BE SOUTH OF THE TERMINAL.

KBDL TERMINAL...MODERATE CONFIDENCE.  PERIOD OF SNOW SHOWERS THIS
MORNING MAY DROP AN INCH OR TWO OF SNOW.  MVFR CONDITIONS DOMINATE
TODAY....BUT A BRIEF PERIOD OF IFR CONDITIONS ARE POSSIBLE THIS
MORNING IN SNOW SHOWERS.

OUTLOOK...MONDAY THROUGH THURSDAY...MODERATE CONFIDENCE.

MONDAY...MVFR CIGS CONTINUE IN RI/EASTERN MASS IN MARINE EAST FLOW.
VFR IN THE WEST.

TUESDAY...VFR WITH SCATTERED MVFR IN ANY RAIN/SNOW SHOWERS.

WEDNESDAY...CONDITIONS LOWERING TO IFR IN RAIN/HEAVY RAIN. ISOLATED
THUNDERSTORMS POSSIBLE ESPECIALLY WEDNESDAY NIGHT. EAST-SOUTHEAST
SURFACE WINDS MAY GUST TO 35-45 KNOTS. WINDS AT 2000 FEET AGL WILL
REACH 50-60 KNOTS WEDNESDAY AFTERNOON AND EARLY NIGHT CREATING LOW
LEVEL WIND SHEAR CONCERNS.

CHRISTMAS DAY...WEST WIND GUSTING 30-40 KNOTS. CONDITIONS IMPROVING
TO VFR AS THE WIND BRINGS IN COOLER DRIER AIR.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /TODAY AND TONIGHT/...HIGH CONFIDENCE.

HIGH PRESSURE ACROSS QUEBEC WILL RESULT IN NORTHEAST WINDS ACROSS
THE WATERS THAT WILL GUST TO BETWEEN 15 AND 20 KNOTS.  THIS WILL
RESULT IN 2 TO 4 FOOT SEAS.  HOWEVER...NO HEADLINES PLANNED AS
CONDITIONS SHOULD REMAIN BELOW SMALL CRAFT ADVISORY THRESHOLDS.

OUTLOOK...MONDAY THROUGH THURSDAY...MODERATE CONFIDENCE

MONDAY...EAST TO NORTHEAST WINDS GUSTING AROUND 15 KNOTS OR LESS.
SEAS WILL HOLD AROUND 3-4 FEET...MAY INCREASE TO 5FT IN NORTHEAST
FLOW AS GUIDANCE MAY BE UNDERDONE.

TUESDAY... INCREASING EAST WINDS WITH FREQUENT GUSTS 25 TO 30 KNOTS.
SEAS WILL BUILD TO 5-6 FEET ON THE EXPOSED WATERS.  A SMALL CRAFT
ADVISORY MAY BE NEEDED.

WEDNESDAY...RAIN WILL BE HEAVY AT TIMES PRODUCING POOR VISIBILITY.
INCREASING SOUTHEAST WINDS 20-25 SUSTAINED AND 40 KNOT GUSTS.  WINDS
SHOULD SHIFT TO SOUTH WEDNESDAY NIGHT AND SOUTHWEST TOWARD THURSDAY
MORNING. RAIN WILL TAPER OFF WITH THE WIND SHIFT TO SOUTHWEST. SEAS
WILL CONTINUE TO BUILD WITH 7-11 FEET HEIGHTS ON THE EXPOSED WATERS.
A GALE WARNING WILL BE NEEDED...WITH A LOW PROB OF A FEW STORM FORCE
GUSTS ACROSS THE EASTERN OUTER WATERS.

CHRISTMAS DAY... WEST SOUTHWEST WINDS WILL CONTINUE TO GUST 35-40
KNOTS...SO A CONTINUED GALE WARNING MAY BE NEEDED. SEAS OF 7-15 FEET
ARE POSSIBLE ON THE EXPOSED WATERS...AND 5 FEET IS POSSIBLE ON SOME
OF THE NEARSHORE WATERS.

&&

.TIDES/COASTAL FLOODING...

HIGH ASTRONOMICAL TIDES WILL OCCUR TUESDAY THROUGH THURSDAY. BREAKING
IT DOWN...ON TUESDAY HIGH TIDE AT BOSTON WILL BE 11.6 FT. THERE WILL
BE ONSHORE FLOW DURING THIS HIGH TIDE ALLOWING FOR MINOR SPLASHOVER.
IF WIND GUSTS INCREASE THEN COULD POSSIBLE SEE MINOR COASTAL
FLOODING.

ON WEDNESDAY...WINDS WILL SWITCH TO A MORE SOUTHEASTERLY FLOW DURING
THE DAY AND INCREASE QUICKLY FROM APPROACHING SYSTEM AND DECENT
PRESSURE FALLS. WEDNESDAY AFTERNOON HIGH TIDE IN BOSTON IS 11.7 FT
AND WITH ANY STRENGTH ON THE EASTERLY WIND FLOW WILL PUSH THE TIDE
OVER. RIGHT NOW BELIEVE MINOR COASTAL FLOODING IS POSSIBLE ALONG THE
EAST COASTLINE.

WEDNESDAY EVENING...THE WIND GOES IN A MORE SOUTHERLY DIRECTION AND
THE TIDE WILL BE INCREASE ACROSS THE SOUTH COAST. HIGH TIDE IN
PROVIDENCE WILL BE 5.2 FT. 925 MB LLJ STRENGTHENS TO 50-60 KTS WHICH
COULD PUSH A DECENT SURGE UP ALONG THE SOUTH COAST DURING THE TIME
OF HIGH TIDE. THINKING THAT MINOR COASTAL FLOODING COULD OCCUR BUT
CANNOT RULE OUT MODERATE ALONG THE SOUTH COAST...ESP IF LLJ
STRENGTHENS EVEN MORE.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...FRANK/DUNTEN
NEAR TERM...FRANK
SHORT TERM...FRANK
LONG TERM...DUNTEN
AVIATION...FRANK/DUNTEN
MARINE...FRANK/DUNTEN
TIDES/COASTAL FLOODING...DUNTEN




000
FXUS61 KBOX 210916
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
416 AM EST SUN DEC 21 2014

.SYNOPSIS...
AN AREA OF SNOW SHOWERS WILL AFFECT AREAS MAINLY SOUTH OF THE MA
TURNPIKE THIS MORNING...EXCEPT IT WILL BE MILD ENOUGH FOR RAIN
SHOWERS ACROSS THE FAR SOUTHEAST NEW ENGLAND COAST. WEAK LOW
PRESSURE WILL PASS SOUTH OF NEW ENGLAND BRINGING ANOTHER PERIOD OF
PRECIPITATION MONDAY NIGHT AND TUESDAY. A MUCH STRONGER STORM
PASSING WEST OF NEW ENGLAND WILL BRING HEAVY RAINFALL...GUSTY
WINDS AND COASTAL FLOODING CONCERNS TO THE REGION WEDNESDAY AND
WEDNESDAY NIGHT. DRY BUT VERY WINDY CONDITIONS FOLLOW FOR
CHRISTMAS DAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...

4 AM UPDATE...

APPROACHING SHORTWAVE HAS ALLOWED AN AREA LIGHT SNOW SHOWERS TO
EXPAND SOUTH OF THE MA TURNPIKE VERY EARLY THIS MORNING...BUT A FEW
SNOW SHOWERS DID EXTEND INTO NORTHERN MA.  RADAR IMAGERY ACTUALLY
OVER SHOOTING SOME OF THE ACTIVITY ACROSS NORTHERN CT...BASED ON
OBSERVATIONS.  THE RAIN/SNOW LINE RUNS ROUGHLY FROM NEWPORT...TO
TAUNTON AND JUST NORTH OF MARSHFIELD.  OVERALL...DO NOT EXPECT MUCH
CHANGE IN THE RAIN/SNOW LINE THIS MORNING BASED ON THERMAL PROFILES
AND POSITIONING OF THE COASTAL FRONT.

MAIN UNCERTAINTY IS JUST HOW MUCH SNOW OCCURS THIS MORNING WITH THE
SHORTWAVE MOVING ACROSS CT.  GIVEN THE TRACK OF THE SHORTWAVE...BEST
FORCING WILL BE LOCATED SOUTH OF THE MA TURNPIKE AND ESPECIALLY
ACROSS NORTHERN CT/RI.  WE WILL FORECAST 1 TO 2 INCHES OF SNOW
ACROSS THIS REGION...BUT A FEW ISOLATED 3 INCH AMOUNTS CAN NOT BE
RULED OUT. MEANWHILE...AREAS NORTH OF THE MA TURNPIKE WILL BE
REMOVED FROM THE BEST FORCING...BUT STILL SEE SOME SCATTERED
SHOWERS.  ACCUMS IN THIS AREA LIKELY TO BE A DUSTING TO LESS THAN AN
INCH.

ALSO...SOME OF THE PRECIPITATION CURRENTLY ACROSS SOUTHEAST MA IS
BEING ENHANCED FROM THE COASTAL FRONT.  A LOT OF THIS PRECIP WILL
BE IN THE FORM OF RAIN SHOWERS ACROSS PLYMOUTH AND EVEN INTO
PORTIONS OF BRISTOL COUNTY...POINTS SOUTH AND EAST.  HOWEVER...AT
LEAST THE SLIGHTLY HIGHER TERRAIN OF SOUTHEAST MA SHOULD SEE SNOW
SHOWERS.  WILL HAVE TO KEEP A CLOSE EYE ON IF COASTAL FRONT SHIFTS
SLIGHTLY THIS MORNING.  IT COULD MEAN THE DIFFERENCE BETWEEN AN AREA
GETTING MAINLY RAIN SHOWERS OR PERHAPS AN INCH OR SO OF SNOW.
OVERALL...DO NOT EXPECT THE COASTAL FRONT TO MOVE TOO MUCH THIS
MORNING...BUT JUST A FEW MILES CAN MAKE DIFFERENCE FOR A
PARTICULARLY NEIGHBORHOOD.

BULK OF PRECIPITATION WILL BE THIS MORNING WITH THE SHORTWAVE.
HOWEVER...ENOUGH LOW LEVEL MOISTURE/WEAK LIFT WILL REMAIN THIS
AFTERNOON FOR AT LEAST THIS RISK OF SCATTERED PRECIPITATION AND WILL
MAINTAIN SOME POPS.  HIGH TEMPS MAINLY IN THE 30S.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...

TONIGHT...

A RATHER CLOUDY AND RAW NIGHT ACROSS SOUTHERN NEW ENGLAND.  WHILE
THERE IS NOT A SIGNIFICANT SHORTWAVE TO TRIGGER A LOT OF
PRECIPITATION...PLENTY OF LOW LEVEL MOISTURE/WEAK SHALLOW LIFT
REMAINS.  THIS MAY BE ENOUGH TO RESULT IN A FEW RAIN/SNOW SHOWER
FROM TIME TO TIME.  PTYPE...WOULD BE MAINLY SNOW SHOWERS EXCEPT TO
THE SOUTHEAST OF A NEWPORT...TO TAUNTON...TO JUST NORTH OF
MARSHFIELD LINE.  AGAIN...MUCH OF THE NIGHT WILL PROBABLY END UP
DRY...BUT JUST THE RISK FOR A FEW RAIN/SNOW SHOWERS.

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...

HIGHLIGHTS...

* WEAK SHORTWAVE ON MON NIGHT/TUESDAY COULD BRING WINTRY
  MIX/FREEZING RAIN TO THE INTERIOR
* ANOMALOUS SYSTEM ACROSS THE GREAT LAKES WILL BRING HEAVY
  RAIN...GUSTY WINDS AND COASTAL FLOODING CONCERNS AROUND CHRISTMAS
  EVE
* BLUSTERY BUT AIRMASS WILL BE DRYING OUT ON CHRISTMAS DAY

OVERVIEW...

THE MODELS AND ENSEMBLES OFFER A REASONABLY SIMILAR AND PREDICTABLE
LARGER SCALE MID TO UPPER LEVEL PATTERN EVOLUTION FOR MUCH OF THE
UPCOMING WEEK. THIS ACTIVE FLOW REGIME DEVELOPS SEVERAL MID-UPPER
LEVEL TROUGH AND ASSOCIATED/UNSETTLING LEAD SURFACE LOW/FRONTAL
SYSTEMS AND PCPN SWATHS PROGRESS STEADILY ACROSS THE LOWER 48. THE
FIRST AMPLIFIED/DEEP LEAD SYSTEM WORKS ACROSS THE ERN/NERN US INTO
ERN CANADA CHRISTMAS EVE INTO CHRISTMAS ALLOWING FOR A MOIST/WARMED
AIRMASS IN ADVANCE OF FRONTAL APPROACH WITH HEAVIEST LEAD QPF
POTENTIAL OVER NEW ENGLAND. BIGGEST QUESTION IS THE EVOLUTION OF THE
SECONDARY LOW PRESSURE SYSTEM. 00Z GUIDANCE HAS BACKED OFF ON THE
STRENGTH OF THE LOW AND IS HAVING ISSUES ON HOW TO HANDLE ITS
EVOLUTION. THE EC AND GFS HAVE SLOWED DOWN THE SYSTEM SLIGHTLY WITH
THE EC HAVING MORE OF A NEGATIVE TROUGH VS THE GFS. BELIEVE THE
UKMET IS A GOOD COMPROMISE AT IS WAS THE FIRST DETERMINISTIC
GUIDANCE ON TAMPERING DOWN THE FIRST MAIN LOW...WHILE THE CMC IS OUT
TO LUNCH. REGARDLESS THIS IS A VERY ANOMALOUS SYSTEM THAT IS ABOUT 4
STANDARD DEVIATIONS AWAY.

A SECONDARY SYSTEM DEEPENS ACROSS THE FOUR CORNERS ON FRIDAY AND
WITH THE STUBBORN TROUGH OVER THE CENTRAL U.S...IT WILL PUSH A
SYSTEM TOWARDS SOUTHERN NEW ENGLAND BY SUNDAY. THIS SYSTEM MAY
SUPPORT A MODEST SWATH OF OVERRUNNING SNOW OVER SOUTHERN NEW
ENGLAND.

DETAILS...

MONDAY INTO TUESDAY...MODERATE CONFIDENCE.

A WEAK WAVE OF LOW PRESSURE DEVELOPS ALONG THE SOUTHEAST COAST
MONDAY...AND WILL BE ON A DEVELOPING WARM FRONTAL BOUNDARY. THIS LOW
REMAINS WEAK AS THE WARM FRONT MOVES SLOWLY NORTH MONDAY NIGHT INTO
TUESDAY. APPEARS THAT THERE IS DECENT WARM ADVECTION AHEAD OF THIS
WAVE. SEVERAL HI-RES GUIDANCE MODELS SHOW THAT THERE IS THE
POTENTIAL FOR COLD AIR DAMMING ACROSS THE INTERIOR INTO TUESDAY.
BIGGEST QUESTION WILL BE IS THERE ENOUGH MOISTURE FOR PRECIP DURING
THIS TIME FRAME. DUE TO A STRENGTHENING LLJ PROVIDING A GOOD SOURCE OF
LIFT ANTICIPATE PRECIP TO DEVELOP AND OVERSPREAD ACROSS SOUTHERN NEW
ENGLAND. IF THIS PLAYS OUT WITH COLD AIR DAMMING AND WARM AIR
ADVECTION...THEN WE COULD SEE FREEZING RAIN/DRIZZLE ACROSS THE I-91
CORRIDOR LATE MONDAY INTO TUESDAY MORNING. DURING THE DAY ON
TUESDAY...GOOD AMOUNT OF WARM AIR WILL PUSH SURFACE TEMPS ABOVE
FREEZING BY THE LATE MORNING ALLOWING FOR ANY PRECIP TO BE MORE OF
THE LIQUID VARIETY AHEAD OF THE CHRISTMAS EVE STORM. HOWEVER
GUIDANCE IS ALWAYS TOO FAST IN SCOURING TEMPS OUT ESP ACROSS THE CT
VALLEY SO WE WILL NEED TO MONITOR THIS CLOSELY...ESP DUE TO LIGHT
WINDS AND THE HIGH IN EASTERN CANADA. A WINTER WX ADVISORY MAY BE
NEEDED FOR THE LIGHT ICING POTENTIAL.

WE COULD ALSO SEE SOME MINOR COASTAL FLOODING CONCERNS ON TUESDAY. SEE
BELOW FOR MORE DETAILS.

WEDNESDAY INTO THURSDAY...HIGH CONFIDENCE IN SYSTEM LOW CONFIDENCE
ON DETAILS.

ANOMALOUS SYSTEM WILL STRENGTHEN OVER THE GREAT LAKES TUESDAY INTO
WEDNESDAY. A SECONDARY SHORTWAVE WILL ROUND THE DEEP TROUGH AND
DEVELOP A SECONDARY LOW PRESSURE ALONG THE COLD FRONT. THIS
SECONDARY LOW WILL STRENGTHEN AND PASS WEST OF SOUTHERN NEW ENGLAND.
THIS SYSTEM WILL CONTINUE TO DEEPEN AS IT MOVES TOWARDS EASTERN
CANADA SWINGING A COLD FRONT ACROSS THE NORTHEAST.

STRONG SOUTHERLY JET OUT AHEAD OF THE FRONT WITH A GULF MOISTURE
CONNECTION WILL IMPACT SOUTHERN NEW ENGLAND ON CHRISTMAS EVE. THIS
STRONG JET WILL YIELD FOR PCPN IN THE LIQUID VARIETY.  PW ANOMALIES
ARE BETWEEN +4 TO +5 STANDARD DEVIATIONS ABOVE NORMAL WHICH IS QUITE
ANOMALOUS FOR THIS TIME OF YEAR. IN FACT CURRENT PWATS ARE PROGGED
ABOVE 1.6 INCHES WITH MODEL QPF OVER 2 INCHES...AT THE VERY LEAST
COULD SEE URBAN AND POOR DRAINAGE FLOODING. LATEST EC EVEN SHOWS
OVER 2.5 INCHES OF QPF...AND WITH THE TROPICAL CONNECTION AND STRONG
SOUTHERLY FLOW COULD SEE HIGHER AMOUNTS DUE TO TOPOGRAPHY
ENHANCEMENTS. RAINFALL RECORDS MAY FALL IF EVERYTHING FALLS INTO
PLACE.

AHEAD OF THE FRONT...SOUTHERN NEW ENGLAND WILL WARM SECTOR WED INTO
THUR MORNING ALLOWING FOR TEMPERATURES TO BE WELL ABOVE AVERAGE. IN
FACT WE MAY BE CLOSE AT BREAKING RECORD HIGH TEMPS IF TEMPS WARM TO
60F OR ABOVE ON CHRISTMAS EVE. SINCE WE WILL BE IN THE WARM
SECTOR...AND SHOWALTERS CLOSE TO ZERO...ISOLATED THUNDER IS STILL
POSSIBLE.

STRONG LOW LEVEL WINDS WILL ALSO BE A CONCERN ESPECIALLY WEDNESDAY
NIGHT. THE ECMWF SHOWS EAST-SOUTHEAST WINDS 30-40 KNOTS ON WEDNESDAY
INCREASING TO 60-75 KNOTS BY WEDNESDAY NIGHT. STRONG DOWNPOURS MAY
OVERCOME THE LOW LEVEL INVERSION AND BRING STRONG GUSTS OF AT LEAST
30-40 KNOTS ESPECIALLY ALONG THE SOUTH COAST. A WIND ADVISORY MAY BE
NEEDED IN SOME AREAS.

CHRISTMAS DAY...MODERATE CONFIDENCE.

AS THE COLD FRONT PASSES THROUGH EARLY CHRISTMAS DAY...THE WEST
WINDS WILL HELP DRY THE AIRMASS ALLOWING FOR PARTLY SUNNY SKIES.
STRONG CAA ON THURSDAY WILL ALLOW DESCENT MIXING. WINDS IN THE SFC-
850 MB LAYER WILL BE 30-40 KNOTS AND POSSIBLY A LITTLE
HIGHER...WHICH WOULD REQUIRE A WIND ADVISORY FOR MUCH OF THE AREA.

FRIDAY-SUNDAY...LOWER CONFIDENCE

WEAK HIGH PRESSURE BUILDS OVER THE AREA FRIDAY INTO SATURDAY. THE
NEXT SHORTWAVE APPROACHES LATE SATURDAY INTO SUNDAY AND SHOULD BRING
INCREASING CLOUDS FROM WEST TO EAST ALONG WITH A CHANCE OF RAIN OR
SNOW SHOWERS MAINLY IN THE AFTERNOON AND AT NIGHT.

&&

.AVIATION /09Z SUNDAY THROUGH THURSDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /TODAY AND TONIGHT/...

TODAY AND TONIGHT...MODERATE CONFIDENCE.  MAINLY MVFR CONDITIONS
SOUTH OF THE MA TURNPIKE WITH BORDERLINE VFR TO MARGINAL MVFR CIGS
NORTH OF THE PIKE THROUGH TONIGHT.  AN AREA OF SNOW SHOWERS WILL
EXPAND MAINLY ACROSS AREAS SOUTH OF THE PIKE THIS MORNING...BUT A
FEW SNOW SHOWERS WILL STILL AFFECT NORTHERN MA.  VSBYS/CIGS MAY
BRIEFLY DROP TO IFR LEVELS IN NORTHERN CT/RI/SE MA.  PTYPE WILL BE
RAIN SHOWERS ACROSS MOST OF PLYMOUTH COUNTY AND ONTO THE
CAPE/ISLANDS WITH SNOW SHOWERS NORTH AND WEST.  BULK OF PRECIP THIS
MORNING...BUT A FEW LINGERING RAIN/SNOW SHOWERS STILL POSSIBLE THIS
AFTERNOON AND EVENING.

KBOS TERMINAL...MODERATE CONFIDENCE.  A FEW SNOW SHOWERS POSSIBLE
THIS MORNING BUT BULK OF ACTIVITY SHOULD BE SOUTH OF THE TERMINAL.

KBDL TERMINAL...MODERATE CONFIDENCE.  PERIOD OF SNOW SHOWERS THIS
MORNING MAY DROP AN INCH OR TWO OF SNOW.  MVFR CONDITIONS DOMINATE
TODAY....BUT A BRIEF PERIOD OF IFR CONDITIONS ARE POSSIBLE THIS
MORNING IN SNOW SHOWERS.

OUTLOOK...MONDAY THROUGH THURSDAY...MODERATE CONFIDENCE.

MONDAY...MVFR CIGS CONTINUE IN RI/EASTERN MASS IN MARINE EAST FLOW.
VFR IN THE WEST.

TUESDAY...VFR WITH SCATTERED MVFR IN ANY RAIN/SNOW SHOWERS.

WEDNESDAY...CONDITIONS LOWERING TO IFR IN RAIN/HEAVY RAIN. ISOLATED
THUNDERSTORMS POSSIBLE ESPECIALLY WEDNESDAY NIGHT. EAST-SOUTHEAST
SURFACE WINDS MAY GUST TO 35-45 KNOTS. WINDS AT 2000 FEET AGL WILL
REACH 50-60 KNOTS WEDNESDAY AFTERNOON AND EARLY NIGHT CREATING LOW
LEVEL WIND SHEAR CONCERNS.

CHRISTMAS DAY...WEST WIND GUSTING 30-40 KNOTS. CONDITIONS IMPROVING
TO VFR AS THE WIND BRINGS IN COOLER DRIER AIR.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /TODAY AND TONIGHT/...HIGH CONFIDENCE.

HIGH PRESSURE ACROSS QUEBEC WILL RESULT IN NORTHEAST WINDS ACROSS
THE WATERS THAT WILL GUST TO BETWEEN 15 AND 20 KNOTS.  THIS WILL
RESULT IN 2 TO 4 FOOT SEAS.  HOWEVER...NO HEADLINES PLANNED AS
CONDITIONS SHOULD REMAIN BELOW SMALL CRAFT ADVISORY THRESHOLDS.

OUTLOOK...MONDAY THROUGH THURSDAY...MODERATE CONFIDENCE

MONDAY...EAST TO NORTHEAST WINDS GUSTING AROUND 15 KNOTS OR LESS.
SEAS WILL HOLD AROUND 3-4 FEET...MAY INCREASE TO 5FT IN NORTHEAST
FLOW AS GUIDANCE MAY BE UNDERDONE.

TUESDAY... INCREASING EAST WINDS WITH FREQUENT GUSTS 25 TO 30 KNOTS.
SEAS WILL BUILD TO 5-6 FEET ON THE EXPOSED WATERS.  A SMALL CRAFT
ADVISORY MAY BE NEEDED.

WEDNESDAY...RAIN WILL BE HEAVY AT TIMES PRODUCING POOR VISIBILITY.
INCREASING SOUTHEAST WINDS 20-25 SUSTAINED AND 40 KNOT GUSTS.  WINDS
SHOULD SHIFT TO SOUTH WEDNESDAY NIGHT AND SOUTHWEST TOWARD THURSDAY
MORNING. RAIN WILL TAPER OFF WITH THE WIND SHIFT TO SOUTHWEST. SEAS
WILL CONTINUE TO BUILD WITH 7-11 FEET HEIGHTS ON THE EXPOSED WATERS.
A GALE WARNING WILL BE NEEDED...WITH A LOW PROB OF A FEW STORM FORCE
GUSTS ACROSS THE EASTERN OUTER WATERS.

CHRISTMAS DAY... WEST SOUTHWEST WINDS WILL CONTINUE TO GUST 35-40
KNOTS...SO A CONTINUED GALE WARNING MAY BE NEEDED. SEAS OF 7-15 FEET
ARE POSSIBLE ON THE EXPOSED WATERS...AND 5 FEET IS POSSIBLE ON SOME
OF THE NEARSHORE WATERS.

&&

.TIDES/COASTAL FLOODING...

HIGH ASTRONOMICAL TIDES WILL OCCUR TUESDAY THROUGH THURSDAY. BREAKING
IT DOWN...ON TUESDAY HIGH TIDE AT BOSTON WILL BE 11.6 FT. THERE WILL
BE ONSHORE FLOW DURING THIS HIGH TIDE ALLOWING FOR MINOR SPLASHOVER.
IF WIND GUSTS INCREASE THEN COULD POSSIBLE SEE MINOR COASTAL
FLOODING.

ON WEDNESDAY...WINDS WILL SWITCH TO A MORE SOUTHEASTERLY FLOW DURING
THE DAY AND INCREASE QUICKLY FROM APPROACHING SYSTEM AND DECENT
PRESSURE FALLS. WEDNESDAY AFTERNOON HIGH TIDE IN BOSTON IS 11.7 FT
AND WITH ANY STRENGTH ON THE EASTERLY WIND FLOW WILL PUSH THE TIDE
OVER. RIGHT NOW BELIEVE MINOR COASTAL FLOODING IS POSSIBLE ALONG THE
EAST COASTLINE.

WEDNESDAY EVENING...THE WIND GOES IN A MORE SOUTHERLY DIRECTION AND
THE TIDE WILL BE INCREASE ACROSS THE SOUTH COAST. HIGH TIDE IN
PROVIDENCE WILL BE 5.2 FT. 925 MB LLJ STRENGTHENS TO 50-60 KTS WHICH
COULD PUSH A DECENT SURGE UP ALONG THE SOUTH COAST DURING THE TIME
OF HIGH TIDE. THINKING THAT MINOR COASTAL FLOODING COULD OCCUR BUT
CANNOT RULE OUT MODERATE ALONG THE SOUTH COAST...ESP IF LLJ
STRENGTHENS EVEN MORE.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...FRANK/DUNTEN
NEAR TERM...FRANK
SHORT TERM...FRANK
LONG TERM...DUNTEN
AVIATION...FRANK/DUNTEN
MARINE...FRANK/DUNTEN
TIDES/COASTAL FLOODING...DUNTEN




000
FXUS61 KBOX 210916
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
416 AM EST SUN DEC 21 2014

.SYNOPSIS...
AN AREA OF SNOW SHOWERS WILL AFFECT AREAS MAINLY SOUTH OF THE MA
TURNPIKE THIS MORNING...EXCEPT IT WILL BE MILD ENOUGH FOR RAIN
SHOWERS ACROSS THE FAR SOUTHEAST NEW ENGLAND COAST. WEAK LOW
PRESSURE WILL PASS SOUTH OF NEW ENGLAND BRINGING ANOTHER PERIOD OF
PRECIPITATION MONDAY NIGHT AND TUESDAY. A MUCH STRONGER STORM
PASSING WEST OF NEW ENGLAND WILL BRING HEAVY RAINFALL...GUSTY
WINDS AND COASTAL FLOODING CONCERNS TO THE REGION WEDNESDAY AND
WEDNESDAY NIGHT. DRY BUT VERY WINDY CONDITIONS FOLLOW FOR
CHRISTMAS DAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...

4 AM UPDATE...

APPROACHING SHORTWAVE HAS ALLOWED AN AREA LIGHT SNOW SHOWERS TO
EXPAND SOUTH OF THE MA TURNPIKE VERY EARLY THIS MORNING...BUT A FEW
SNOW SHOWERS DID EXTEND INTO NORTHERN MA.  RADAR IMAGERY ACTUALLY
OVER SHOOTING SOME OF THE ACTIVITY ACROSS NORTHERN CT...BASED ON
OBSERVATIONS.  THE RAIN/SNOW LINE RUNS ROUGHLY FROM NEWPORT...TO
TAUNTON AND JUST NORTH OF MARSHFIELD.  OVERALL...DO NOT EXPECT MUCH
CHANGE IN THE RAIN/SNOW LINE THIS MORNING BASED ON THERMAL PROFILES
AND POSITIONING OF THE COASTAL FRONT.

MAIN UNCERTAINTY IS JUST HOW MUCH SNOW OCCURS THIS MORNING WITH THE
SHORTWAVE MOVING ACROSS CT.  GIVEN THE TRACK OF THE SHORTWAVE...BEST
FORCING WILL BE LOCATED SOUTH OF THE MA TURNPIKE AND ESPECIALLY
ACROSS NORTHERN CT/RI.  WE WILL FORECAST 1 TO 2 INCHES OF SNOW
ACROSS THIS REGION...BUT A FEW ISOLATED 3 INCH AMOUNTS CAN NOT BE
RULED OUT. MEANWHILE...AREAS NORTH OF THE MA TURNPIKE WILL BE
REMOVED FROM THE BEST FORCING...BUT STILL SEE SOME SCATTERED
SHOWERS.  ACCUMS IN THIS AREA LIKELY TO BE A DUSTING TO LESS THAN AN
INCH.

ALSO...SOME OF THE PRECIPITATION CURRENTLY ACROSS SOUTHEAST MA IS
BEING ENHANCED FROM THE COASTAL FRONT.  A LOT OF THIS PRECIP WILL
BE IN THE FORM OF RAIN SHOWERS ACROSS PLYMOUTH AND EVEN INTO
PORTIONS OF BRISTOL COUNTY...POINTS SOUTH AND EAST.  HOWEVER...AT
LEAST THE SLIGHTLY HIGHER TERRAIN OF SOUTHEAST MA SHOULD SEE SNOW
SHOWERS.  WILL HAVE TO KEEP A CLOSE EYE ON IF COASTAL FRONT SHIFTS
SLIGHTLY THIS MORNING.  IT COULD MEAN THE DIFFERENCE BETWEEN AN AREA
GETTING MAINLY RAIN SHOWERS OR PERHAPS AN INCH OR SO OF SNOW.
OVERALL...DO NOT EXPECT THE COASTAL FRONT TO MOVE TOO MUCH THIS
MORNING...BUT JUST A FEW MILES CAN MAKE DIFFERENCE FOR A
PARTICULARLY NEIGHBORHOOD.

BULK OF PRECIPITATION WILL BE THIS MORNING WITH THE SHORTWAVE.
HOWEVER...ENOUGH LOW LEVEL MOISTURE/WEAK LIFT WILL REMAIN THIS
AFTERNOON FOR AT LEAST THIS RISK OF SCATTERED PRECIPITATION AND WILL
MAINTAIN SOME POPS.  HIGH TEMPS MAINLY IN THE 30S.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...

TONIGHT...

A RATHER CLOUDY AND RAW NIGHT ACROSS SOUTHERN NEW ENGLAND.  WHILE
THERE IS NOT A SIGNIFICANT SHORTWAVE TO TRIGGER A LOT OF
PRECIPITATION...PLENTY OF LOW LEVEL MOISTURE/WEAK SHALLOW LIFT
REMAINS.  THIS MAY BE ENOUGH TO RESULT IN A FEW RAIN/SNOW SHOWER
FROM TIME TO TIME.  PTYPE...WOULD BE MAINLY SNOW SHOWERS EXCEPT TO
THE SOUTHEAST OF A NEWPORT...TO TAUNTON...TO JUST NORTH OF
MARSHFIELD LINE.  AGAIN...MUCH OF THE NIGHT WILL PROBABLY END UP
DRY...BUT JUST THE RISK FOR A FEW RAIN/SNOW SHOWERS.

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...

HIGHLIGHTS...

* WEAK SHORTWAVE ON MON NIGHT/TUESDAY COULD BRING WINTRY
  MIX/FREEZING RAIN TO THE INTERIOR
* ANOMALOUS SYSTEM ACROSS THE GREAT LAKES WILL BRING HEAVY
  RAIN...GUSTY WINDS AND COASTAL FLOODING CONCERNS AROUND CHRISTMAS
  EVE
* BLUSTERY BUT AIRMASS WILL BE DRYING OUT ON CHRISTMAS DAY

OVERVIEW...

THE MODELS AND ENSEMBLES OFFER A REASONABLY SIMILAR AND PREDICTABLE
LARGER SCALE MID TO UPPER LEVEL PATTERN EVOLUTION FOR MUCH OF THE
UPCOMING WEEK. THIS ACTIVE FLOW REGIME DEVELOPS SEVERAL MID-UPPER
LEVEL TROUGH AND ASSOCIATED/UNSETTLING LEAD SURFACE LOW/FRONTAL
SYSTEMS AND PCPN SWATHS PROGRESS STEADILY ACROSS THE LOWER 48. THE
FIRST AMPLIFIED/DEEP LEAD SYSTEM WORKS ACROSS THE ERN/NERN US INTO
ERN CANADA CHRISTMAS EVE INTO CHRISTMAS ALLOWING FOR A MOIST/WARMED
AIRMASS IN ADVANCE OF FRONTAL APPROACH WITH HEAVIEST LEAD QPF
POTENTIAL OVER NEW ENGLAND. BIGGEST QUESTION IS THE EVOLUTION OF THE
SECONDARY LOW PRESSURE SYSTEM. 00Z GUIDANCE HAS BACKED OFF ON THE
STRENGTH OF THE LOW AND IS HAVING ISSUES ON HOW TO HANDLE ITS
EVOLUTION. THE EC AND GFS HAVE SLOWED DOWN THE SYSTEM SLIGHTLY WITH
THE EC HAVING MORE OF A NEGATIVE TROUGH VS THE GFS. BELIEVE THE
UKMET IS A GOOD COMPROMISE AT IS WAS THE FIRST DETERMINISTIC
GUIDANCE ON TAMPERING DOWN THE FIRST MAIN LOW...WHILE THE CMC IS OUT
TO LUNCH. REGARDLESS THIS IS A VERY ANOMALOUS SYSTEM THAT IS ABOUT 4
STANDARD DEVIATIONS AWAY.

A SECONDARY SYSTEM DEEPENS ACROSS THE FOUR CORNERS ON FRIDAY AND
WITH THE STUBBORN TROUGH OVER THE CENTRAL U.S...IT WILL PUSH A
SYSTEM TOWARDS SOUTHERN NEW ENGLAND BY SUNDAY. THIS SYSTEM MAY
SUPPORT A MODEST SWATH OF OVERRUNNING SNOW OVER SOUTHERN NEW
ENGLAND.

DETAILS...

MONDAY INTO TUESDAY...MODERATE CONFIDENCE.

A WEAK WAVE OF LOW PRESSURE DEVELOPS ALONG THE SOUTHEAST COAST
MONDAY...AND WILL BE ON A DEVELOPING WARM FRONTAL BOUNDARY. THIS LOW
REMAINS WEAK AS THE WARM FRONT MOVES SLOWLY NORTH MONDAY NIGHT INTO
TUESDAY. APPEARS THAT THERE IS DECENT WARM ADVECTION AHEAD OF THIS
WAVE. SEVERAL HI-RES GUIDANCE MODELS SHOW THAT THERE IS THE
POTENTIAL FOR COLD AIR DAMMING ACROSS THE INTERIOR INTO TUESDAY.
BIGGEST QUESTION WILL BE IS THERE ENOUGH MOISTURE FOR PRECIP DURING
THIS TIME FRAME. DUE TO A STRENGTHENING LLJ PROVIDING A GOOD SOURCE OF
LIFT ANTICIPATE PRECIP TO DEVELOP AND OVERSPREAD ACROSS SOUTHERN NEW
ENGLAND. IF THIS PLAYS OUT WITH COLD AIR DAMMING AND WARM AIR
ADVECTION...THEN WE COULD SEE FREEZING RAIN/DRIZZLE ACROSS THE I-91
CORRIDOR LATE MONDAY INTO TUESDAY MORNING. DURING THE DAY ON
TUESDAY...GOOD AMOUNT OF WARM AIR WILL PUSH SURFACE TEMPS ABOVE
FREEZING BY THE LATE MORNING ALLOWING FOR ANY PRECIP TO BE MORE OF
THE LIQUID VARIETY AHEAD OF THE CHRISTMAS EVE STORM. HOWEVER
GUIDANCE IS ALWAYS TOO FAST IN SCOURING TEMPS OUT ESP ACROSS THE CT
VALLEY SO WE WILL NEED TO MONITOR THIS CLOSELY...ESP DUE TO LIGHT
WINDS AND THE HIGH IN EASTERN CANADA. A WINTER WX ADVISORY MAY BE
NEEDED FOR THE LIGHT ICING POTENTIAL.

WE COULD ALSO SEE SOME MINOR COASTAL FLOODING CONCERNS ON TUESDAY. SEE
BELOW FOR MORE DETAILS.

WEDNESDAY INTO THURSDAY...HIGH CONFIDENCE IN SYSTEM LOW CONFIDENCE
ON DETAILS.

ANOMALOUS SYSTEM WILL STRENGTHEN OVER THE GREAT LAKES TUESDAY INTO
WEDNESDAY. A SECONDARY SHORTWAVE WILL ROUND THE DEEP TROUGH AND
DEVELOP A SECONDARY LOW PRESSURE ALONG THE COLD FRONT. THIS
SECONDARY LOW WILL STRENGTHEN AND PASS WEST OF SOUTHERN NEW ENGLAND.
THIS SYSTEM WILL CONTINUE TO DEEPEN AS IT MOVES TOWARDS EASTERN
CANADA SWINGING A COLD FRONT ACROSS THE NORTHEAST.

STRONG SOUTHERLY JET OUT AHEAD OF THE FRONT WITH A GULF MOISTURE
CONNECTION WILL IMPACT SOUTHERN NEW ENGLAND ON CHRISTMAS EVE. THIS
STRONG JET WILL YIELD FOR PCPN IN THE LIQUID VARIETY.  PW ANOMALIES
ARE BETWEEN +4 TO +5 STANDARD DEVIATIONS ABOVE NORMAL WHICH IS QUITE
ANOMALOUS FOR THIS TIME OF YEAR. IN FACT CURRENT PWATS ARE PROGGED
ABOVE 1.6 INCHES WITH MODEL QPF OVER 2 INCHES...AT THE VERY LEAST
COULD SEE URBAN AND POOR DRAINAGE FLOODING. LATEST EC EVEN SHOWS
OVER 2.5 INCHES OF QPF...AND WITH THE TROPICAL CONNECTION AND STRONG
SOUTHERLY FLOW COULD SEE HIGHER AMOUNTS DUE TO TOPOGRAPHY
ENHANCEMENTS. RAINFALL RECORDS MAY FALL IF EVERYTHING FALLS INTO
PLACE.

AHEAD OF THE FRONT...SOUTHERN NEW ENGLAND WILL WARM SECTOR WED INTO
THUR MORNING ALLOWING FOR TEMPERATURES TO BE WELL ABOVE AVERAGE. IN
FACT WE MAY BE CLOSE AT BREAKING RECORD HIGH TEMPS IF TEMPS WARM TO
60F OR ABOVE ON CHRISTMAS EVE. SINCE WE WILL BE IN THE WARM
SECTOR...AND SHOWALTERS CLOSE TO ZERO...ISOLATED THUNDER IS STILL
POSSIBLE.

STRONG LOW LEVEL WINDS WILL ALSO BE A CONCERN ESPECIALLY WEDNESDAY
NIGHT. THE ECMWF SHOWS EAST-SOUTHEAST WINDS 30-40 KNOTS ON WEDNESDAY
INCREASING TO 60-75 KNOTS BY WEDNESDAY NIGHT. STRONG DOWNPOURS MAY
OVERCOME THE LOW LEVEL INVERSION AND BRING STRONG GUSTS OF AT LEAST
30-40 KNOTS ESPECIALLY ALONG THE SOUTH COAST. A WIND ADVISORY MAY BE
NEEDED IN SOME AREAS.

CHRISTMAS DAY...MODERATE CONFIDENCE.

AS THE COLD FRONT PASSES THROUGH EARLY CHRISTMAS DAY...THE WEST
WINDS WILL HELP DRY THE AIRMASS ALLOWING FOR PARTLY SUNNY SKIES.
STRONG CAA ON THURSDAY WILL ALLOW DESCENT MIXING. WINDS IN THE SFC-
850 MB LAYER WILL BE 30-40 KNOTS AND POSSIBLY A LITTLE
HIGHER...WHICH WOULD REQUIRE A WIND ADVISORY FOR MUCH OF THE AREA.

FRIDAY-SUNDAY...LOWER CONFIDENCE

WEAK HIGH PRESSURE BUILDS OVER THE AREA FRIDAY INTO SATURDAY. THE
NEXT SHORTWAVE APPROACHES LATE SATURDAY INTO SUNDAY AND SHOULD BRING
INCREASING CLOUDS FROM WEST TO EAST ALONG WITH A CHANCE OF RAIN OR
SNOW SHOWERS MAINLY IN THE AFTERNOON AND AT NIGHT.

&&

.AVIATION /09Z SUNDAY THROUGH THURSDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /TODAY AND TONIGHT/...

TODAY AND TONIGHT...MODERATE CONFIDENCE.  MAINLY MVFR CONDITIONS
SOUTH OF THE MA TURNPIKE WITH BORDERLINE VFR TO MARGINAL MVFR CIGS
NORTH OF THE PIKE THROUGH TONIGHT.  AN AREA OF SNOW SHOWERS WILL
EXPAND MAINLY ACROSS AREAS SOUTH OF THE PIKE THIS MORNING...BUT A
FEW SNOW SHOWERS WILL STILL AFFECT NORTHERN MA.  VSBYS/CIGS MAY
BRIEFLY DROP TO IFR LEVELS IN NORTHERN CT/RI/SE MA.  PTYPE WILL BE
RAIN SHOWERS ACROSS MOST OF PLYMOUTH COUNTY AND ONTO THE
CAPE/ISLANDS WITH SNOW SHOWERS NORTH AND WEST.  BULK OF PRECIP THIS
MORNING...BUT A FEW LINGERING RAIN/SNOW SHOWERS STILL POSSIBLE THIS
AFTERNOON AND EVENING.

KBOS TERMINAL...MODERATE CONFIDENCE.  A FEW SNOW SHOWERS POSSIBLE
THIS MORNING BUT BULK OF ACTIVITY SHOULD BE SOUTH OF THE TERMINAL.

KBDL TERMINAL...MODERATE CONFIDENCE.  PERIOD OF SNOW SHOWERS THIS
MORNING MAY DROP AN INCH OR TWO OF SNOW.  MVFR CONDITIONS DOMINATE
TODAY....BUT A BRIEF PERIOD OF IFR CONDITIONS ARE POSSIBLE THIS
MORNING IN SNOW SHOWERS.

OUTLOOK...MONDAY THROUGH THURSDAY...MODERATE CONFIDENCE.

MONDAY...MVFR CIGS CONTINUE IN RI/EASTERN MASS IN MARINE EAST FLOW.
VFR IN THE WEST.

TUESDAY...VFR WITH SCATTERED MVFR IN ANY RAIN/SNOW SHOWERS.

WEDNESDAY...CONDITIONS LOWERING TO IFR IN RAIN/HEAVY RAIN. ISOLATED
THUNDERSTORMS POSSIBLE ESPECIALLY WEDNESDAY NIGHT. EAST-SOUTHEAST
SURFACE WINDS MAY GUST TO 35-45 KNOTS. WINDS AT 2000 FEET AGL WILL
REACH 50-60 KNOTS WEDNESDAY AFTERNOON AND EARLY NIGHT CREATING LOW
LEVEL WIND SHEAR CONCERNS.

CHRISTMAS DAY...WEST WIND GUSTING 30-40 KNOTS. CONDITIONS IMPROVING
TO VFR AS THE WIND BRINGS IN COOLER DRIER AIR.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /TODAY AND TONIGHT/...HIGH CONFIDENCE.

HIGH PRESSURE ACROSS QUEBEC WILL RESULT IN NORTHEAST WINDS ACROSS
THE WATERS THAT WILL GUST TO BETWEEN 15 AND 20 KNOTS.  THIS WILL
RESULT IN 2 TO 4 FOOT SEAS.  HOWEVER...NO HEADLINES PLANNED AS
CONDITIONS SHOULD REMAIN BELOW SMALL CRAFT ADVISORY THRESHOLDS.

OUTLOOK...MONDAY THROUGH THURSDAY...MODERATE CONFIDENCE

MONDAY...EAST TO NORTHEAST WINDS GUSTING AROUND 15 KNOTS OR LESS.
SEAS WILL HOLD AROUND 3-4 FEET...MAY INCREASE TO 5FT IN NORTHEAST
FLOW AS GUIDANCE MAY BE UNDERDONE.

TUESDAY... INCREASING EAST WINDS WITH FREQUENT GUSTS 25 TO 30 KNOTS.
SEAS WILL BUILD TO 5-6 FEET ON THE EXPOSED WATERS.  A SMALL CRAFT
ADVISORY MAY BE NEEDED.

WEDNESDAY...RAIN WILL BE HEAVY AT TIMES PRODUCING POOR VISIBILITY.
INCREASING SOUTHEAST WINDS 20-25 SUSTAINED AND 40 KNOT GUSTS.  WINDS
SHOULD SHIFT TO SOUTH WEDNESDAY NIGHT AND SOUTHWEST TOWARD THURSDAY
MORNING. RAIN WILL TAPER OFF WITH THE WIND SHIFT TO SOUTHWEST. SEAS
WILL CONTINUE TO BUILD WITH 7-11 FEET HEIGHTS ON THE EXPOSED WATERS.
A GALE WARNING WILL BE NEEDED...WITH A LOW PROB OF A FEW STORM FORCE
GUSTS ACROSS THE EASTERN OUTER WATERS.

CHRISTMAS DAY... WEST SOUTHWEST WINDS WILL CONTINUE TO GUST 35-40
KNOTS...SO A CONTINUED GALE WARNING MAY BE NEEDED. SEAS OF 7-15 FEET
ARE POSSIBLE ON THE EXPOSED WATERS...AND 5 FEET IS POSSIBLE ON SOME
OF THE NEARSHORE WATERS.

&&

.TIDES/COASTAL FLOODING...

HIGH ASTRONOMICAL TIDES WILL OCCUR TUESDAY THROUGH THURSDAY. BREAKING
IT DOWN...ON TUESDAY HIGH TIDE AT BOSTON WILL BE 11.6 FT. THERE WILL
BE ONSHORE FLOW DURING THIS HIGH TIDE ALLOWING FOR MINOR SPLASHOVER.
IF WIND GUSTS INCREASE THEN COULD POSSIBLE SEE MINOR COASTAL
FLOODING.

ON WEDNESDAY...WINDS WILL SWITCH TO A MORE SOUTHEASTERLY FLOW DURING
THE DAY AND INCREASE QUICKLY FROM APPROACHING SYSTEM AND DECENT
PRESSURE FALLS. WEDNESDAY AFTERNOON HIGH TIDE IN BOSTON IS 11.7 FT
AND WITH ANY STRENGTH ON THE EASTERLY WIND FLOW WILL PUSH THE TIDE
OVER. RIGHT NOW BELIEVE MINOR COASTAL FLOODING IS POSSIBLE ALONG THE
EAST COASTLINE.

WEDNESDAY EVENING...THE WIND GOES IN A MORE SOUTHERLY DIRECTION AND
THE TIDE WILL BE INCREASE ACROSS THE SOUTH COAST. HIGH TIDE IN
PROVIDENCE WILL BE 5.2 FT. 925 MB LLJ STRENGTHENS TO 50-60 KTS WHICH
COULD PUSH A DECENT SURGE UP ALONG THE SOUTH COAST DURING THE TIME
OF HIGH TIDE. THINKING THAT MINOR COASTAL FLOODING COULD OCCUR BUT
CANNOT RULE OUT MODERATE ALONG THE SOUTH COAST...ESP IF LLJ
STRENGTHENS EVEN MORE.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...FRANK/DUNTEN
NEAR TERM...FRANK
SHORT TERM...FRANK
LONG TERM...DUNTEN
AVIATION...FRANK/DUNTEN
MARINE...FRANK/DUNTEN
TIDES/COASTAL FLOODING...DUNTEN




000
FXUS61 KGYX 210854
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
354 AM EST SUN DEC 21 2014

.SYNOPSIS...
HIGH PRESSURE BUILDS OVER NORTHERN MAINE SUNDAY...ALLOWING THE
FLOW TO TURN ONSHORE. A WEAK WEATHER DISTURBANCE MAY TRIGGER SOME
FLURRIES OR LIGHT SNOW OVER SOUTHERN REGIONS RIGHT THROUGH MONDAY.
A SIGNIFICANT LOW PRESSURE SYSTEM SYSTEM WILL GRADUALLY ORGANIZE
WEDNESDAY...BEFORE MOVING OVER THE GREAT LAKES. THIS COULD BRING
WINDY CONDITIONS AND THE POTENTIAL FOR HEAVY RAIN AROUND CHRISTMAS
EVE INTO EARLY CHRISTMAS MORNING.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LOW STRATUS BLANKETS THE CWFA AS A SURFACE HIGH PRESSURE IN
SOUTHERN QUEBEC IS HELPING TO KEEP MOISTURE TRAPPED IN THE LOW
LEVELS. A WEAK SHORTWAVE THAT IS PASSING OVER THE SOUTHERN NEW
ENGLAND THIS MORNING AND THIS MAY HELP KICK OFF SOME LIGHT SNOW
ACROSS THE FAR SOUTHERN AREAS OF NEW HAMPSHIRE AND PARTS OF
SOUTHWEST MAINE...AS ON SHORE FLOW SUPPLIES THE LOW LEVEL MOISTURE
THE LIFT FROM THIS WEAK SHORT MAY BE JUST ENOUGH TO PRODUCE SNOW
SHOWERS HEAVY ENOUGH TO ACCUMULATE IN SOME AREAS. AS THIS WEAK
WAVE MOVES EAST OUR FLOW...ALTHOUGH VERY WEAK...WILL TURN TO
NORTHWESTERLY AND THIS MAY BE ENOUGH TO START CLEARING OUT SOME OF
THE LOW STRATUS SUNDAY NIGHT.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/...
FLOW WILL SWITCH BACK TO ON SHORE BY NOON ON MONDAY AND THIS WILL
BRING LIGHT OCEAN EFFECT SNOW OR MAYBE EVEN SOME LIGHT RAIN OR
EVEN FREEZING DRIZZLE INTO THE INTERIOR AS TEMPERATURES WILL HOVER
CLOSE TO FREEZING AS YOU GET AWAY FROM THE COAST.

&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
MODELS CONTINUE TO TREND TOWARD UPSTREAM AND DOWNSTREAM
BLOCKING...WITH AN EVENTUAL RETURN TO A +PNA PATTERN AT
500MB...WHICH WOULD SIGNAL COOLING LATE IN THE PERIOD. HOWEVER
ALL THE ACTION WILL BE IN DAYS 3 TO 5 AS THE UPSTREAM DEVELOPS AND
SENDS WAVES INTO TROUGH OVER CENTRAL CONUS...AMPLIFYING THE 500
MB FLOW.

INITIALLY...WILL BE DEALING WITH SMALLER SCALE FEATURE AS
INVERTED TROUGH OVER THE GULF OF ME WORK ITS WAY ONSHORE MON NIGHT
AND WEAKENS. MAY BE ENOUGH DYNAMIC FORCING FOR ICE CRYSTALS
INITIALLY...SO RAIN OR SNOW SHOWERS MOVE ONSHORE AND INLAND DURING
THE EVENING...BUT COULD SEE IT TURN TO DZ/FZDZ AS WE WE JUST
TRANSPORT WATER DROPLETS ONSHORE. WE MAINTAIN AN ONSHORE FLOW INTO
TUESDAY...BUT IT LOOKS LIKE FORCING WILL BE LIMITED TO
UPSLOPE...SO THINKING MORE IN THE WAY OF SHSN/SHRA/VERY LIGHT SNOW
INLAND...WITH JUST CLOUDS ON THE COAST. SHOULD SEE TEMPS ON TUE
WARM INTO THE UPPER 30S TO MID 40S.

THE MAIN EVENT REMAINS THE IMPRESSIVE 500 MB TROUGH THAT DEVELOPS
OVER THE CENTRAL CONUS MID WEEK...NOT SO MUCH IN THAT IT IS VERY
DEEP...BUT MORE ITS AMPLITUDE AS IT EXTENDS FROM N OF THE GREAT
LAKES SWD INTO THE GULF OF MEX....AND THEN TILTS VERY NEG AND
LIFTS POLEWARD WED NIGHT AND THU. NOT SURE HOW MUCH AN EFFECT
CONVECTIVE SCALING ISSUES ARE HAVING ON THE MODELS...BUT IT MAY BE
HAVING SOME EFFECT ON THE FORECAST DETAILS...BUT PROB NOT THE
GENERALITIES OF THE FORECAST. HOWEVER...00Z EURO AND GFS BOTH SHOW
A WEAKER SFC LOW IN THE VCNITY OF THE GRT LAKES AND ST LAWRENCE
VLY /ALTHOUGH IT DOES INTENSIFY FURTHER N AND E THAN PREV MODEL
RUNS. STILL...AS THAT WAVE LIFTS NWD WILL SEE TRIPLE POINT DEVELOP
OVER THE MID ATLANTIC WED EVE...AND LIFT NNE INTO THE CWA BY THU
MORNING. THIS WILL CREATE A DEEP SOUTHERLY FLOW WHICH WILL CONNECT
WITH GULF MOISTURE...ALLOWING FOR SIGNIFICANT RAINFALL...FROM
LATE IN THE DAY WED...INTO EARLY THU MORNING. QPF LOOKS TO RUN
AROUND 2-3 INCHES IN MANY SPOTS...BUT S-SE UPSLOPE AREAS OF THE
FOOTHILLS AND MTNS COULD SEE AN INCH OR TWO MORE...SO THE THREAT
OF BOTH FLASH AND MAINSTEM FLOODING IS A CONCERN...ESPECIALLY
SINCE THIS WILL BE COMBINE WITH SIGNIFICANT SNOWMELT AS HIGHS
RISE WELL INTO THE 40S WED..AND WILL LKLY STAY THERE WED NIGHT
INTO THU.

THERE IS STILL THE POTENTIAL FOR SOME STRONG GUSTS...BUT GIVEN
WEAKER SYSTEM...THE WINDOW FOR OPPORTUNITY WILL BE LIMITED TO A
FE HOURS AHEAD OF THE TRIPLE POINT PASSAGE...WHICH LOOKS TO BE WED
EVE...AT LEAST FOR NOW. WITH ALL THAT SAID...WE ARE STILL DEALING
WITH DAYS 4 AND 5 OF THE FORECAST...WITH THE POTENTIAL FRO SOME
DEEP CONVECTION IN THE BASE OF THE TROUGH...SO FORECAST COULD
CHANGE...BUT BOTH EURO AND GFS PICKED UP THE SIGNALS OF THIS
SYSTEM EARLY...AND HAVE BEEN CONSISTENT ON THE WHOLE SO FAR.

CHRISTMAS DAY WILL SEE RAIN ENDING FROM SW TO NE DURING THE
MORNING...WITH SOME PARTIAL CLEARING POSSIBLE IN THE
AFTERNOON...AND TEMPS IN THE 40S AGAIN. COOLER AIR WILL MOVE IN
FROM THE SW THU NIGHT. FRI AND SAT LOOK MOSTLY DRY /OTHER THAN
POSSIBLE UPSLOPE SHSN ON FRI/. HIGHS WILL CONTINUE TO RUN A FEW
DEGREES ABV NORMAL.


&&

.AVIATION /08Z SUNDAY THROUGH THURSDAY/...
SHORT TERM...MVFR TO IFR CEILINGS WILL REMAIN OVER THE REGION
THROUGH AT LEAST SUNDAY EVENING. CONDITIONS MAY IMPROVE A BIT
SUNDAY NIGHT AS THE ON SHORE FLOW DRIFTING MOISTURE INLAND WILL
GET SHUT OFF. CONDITIONS WILL NOT STAY UP LONG HOWEVER AS THE FLOW
WILL SWITCH BACK TO ON SHORE ON MONDAY BRINGING ANOTHER ROUND OF
MVFR TO IFR CEILINGS.

LONG TERM...POSSIBLE PERIODS OF MVFR TO IFR MONDAY NIGHT AS
INVERTED TROUGH MOVES INLAND. MVFR LIKELY TO HOLD TUESDAY INTO
TUESDAY NIGHT...LOWERING TO IFR LATE TUESDAY NIGHT INTO THURSDAY
MORNING IN RAIN...WITH INCREASING E-SE WINDS WEDNESDAY.

&&

.MARINE...
SHORT TERM...A FEW WIND GUSTS CONTINUE JUST BELOW 25 KTS THIS
AFTERNOON...WITH WAVES 4` OR LOWER...THEREFORE NO FLAGS IN THE
NEAR TERM. WINDS SHOULD CONTINUE TO SLOWLY DECREASE TONIGHT INTO
TOMORROW FROM THE NORTHEAST.

LONG TERM...HIGH PRESSURE WITH LIGHT AND FAIRLY CALM SEAS WILL
PERSIST THROUGH THE PERIOD AND NO FLAGS ARE EXPECTED.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.

&&

$$
KISTNER/CEMPA



000
FXUS61 KGYX 210854
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
354 AM EST SUN DEC 21 2014

.SYNOPSIS...
HIGH PRESSURE BUILDS OVER NORTHERN MAINE SUNDAY...ALLOWING THE
FLOW TO TURN ONSHORE. A WEAK WEATHER DISTURBANCE MAY TRIGGER SOME
FLURRIES OR LIGHT SNOW OVER SOUTHERN REGIONS RIGHT THROUGH MONDAY.
A SIGNIFICANT LOW PRESSURE SYSTEM SYSTEM WILL GRADUALLY ORGANIZE
WEDNESDAY...BEFORE MOVING OVER THE GREAT LAKES. THIS COULD BRING
WINDY CONDITIONS AND THE POTENTIAL FOR HEAVY RAIN AROUND CHRISTMAS
EVE INTO EARLY CHRISTMAS MORNING.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LOW STRATUS BLANKETS THE CWFA AS A SURFACE HIGH PRESSURE IN
SOUTHERN QUEBEC IS HELPING TO KEEP MOISTURE TRAPPED IN THE LOW
LEVELS. A WEAK SHORTWAVE THAT IS PASSING OVER THE SOUTHERN NEW
ENGLAND THIS MORNING AND THIS MAY HELP KICK OFF SOME LIGHT SNOW
ACROSS THE FAR SOUTHERN AREAS OF NEW HAMPSHIRE AND PARTS OF
SOUTHWEST MAINE...AS ON SHORE FLOW SUPPLIES THE LOW LEVEL MOISTURE
THE LIFT FROM THIS WEAK SHORT MAY BE JUST ENOUGH TO PRODUCE SNOW
SHOWERS HEAVY ENOUGH TO ACCUMULATE IN SOME AREAS. AS THIS WEAK
WAVE MOVES EAST OUR FLOW...ALTHOUGH VERY WEAK...WILL TURN TO
NORTHWESTERLY AND THIS MAY BE ENOUGH TO START CLEARING OUT SOME OF
THE LOW STRATUS SUNDAY NIGHT.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/...
FLOW WILL SWITCH BACK TO ON SHORE BY NOON ON MONDAY AND THIS WILL
BRING LIGHT OCEAN EFFECT SNOW OR MAYBE EVEN SOME LIGHT RAIN OR
EVEN FREEZING DRIZZLE INTO THE INTERIOR AS TEMPERATURES WILL HOVER
CLOSE TO FREEZING AS YOU GET AWAY FROM THE COAST.

&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
MODELS CONTINUE TO TREND TOWARD UPSTREAM AND DOWNSTREAM
BLOCKING...WITH AN EVENTUAL RETURN TO A +PNA PATTERN AT
500MB...WHICH WOULD SIGNAL COOLING LATE IN THE PERIOD. HOWEVER
ALL THE ACTION WILL BE IN DAYS 3 TO 5 AS THE UPSTREAM DEVELOPS AND
SENDS WAVES INTO TROUGH OVER CENTRAL CONUS...AMPLIFYING THE 500
MB FLOW.

INITIALLY...WILL BE DEALING WITH SMALLER SCALE FEATURE AS
INVERTED TROUGH OVER THE GULF OF ME WORK ITS WAY ONSHORE MON NIGHT
AND WEAKENS. MAY BE ENOUGH DYNAMIC FORCING FOR ICE CRYSTALS
INITIALLY...SO RAIN OR SNOW SHOWERS MOVE ONSHORE AND INLAND DURING
THE EVENING...BUT COULD SEE IT TURN TO DZ/FZDZ AS WE WE JUST
TRANSPORT WATER DROPLETS ONSHORE. WE MAINTAIN AN ONSHORE FLOW INTO
TUESDAY...BUT IT LOOKS LIKE FORCING WILL BE LIMITED TO
UPSLOPE...SO THINKING MORE IN THE WAY OF SHSN/SHRA/VERY LIGHT SNOW
INLAND...WITH JUST CLOUDS ON THE COAST. SHOULD SEE TEMPS ON TUE
WARM INTO THE UPPER 30S TO MID 40S.

THE MAIN EVENT REMAINS THE IMPRESSIVE 500 MB TROUGH THAT DEVELOPS
OVER THE CENTRAL CONUS MID WEEK...NOT SO MUCH IN THAT IT IS VERY
DEEP...BUT MORE ITS AMPLITUDE AS IT EXTENDS FROM N OF THE GREAT
LAKES SWD INTO THE GULF OF MEX....AND THEN TILTS VERY NEG AND
LIFTS POLEWARD WED NIGHT AND THU. NOT SURE HOW MUCH AN EFFECT
CONVECTIVE SCALING ISSUES ARE HAVING ON THE MODELS...BUT IT MAY BE
HAVING SOME EFFECT ON THE FORECAST DETAILS...BUT PROB NOT THE
GENERALITIES OF THE FORECAST. HOWEVER...00Z EURO AND GFS BOTH SHOW
A WEAKER SFC LOW IN THE VCNITY OF THE GRT LAKES AND ST LAWRENCE
VLY /ALTHOUGH IT DOES INTENSIFY FURTHER N AND E THAN PREV MODEL
RUNS. STILL...AS THAT WAVE LIFTS NWD WILL SEE TRIPLE POINT DEVELOP
OVER THE MID ATLANTIC WED EVE...AND LIFT NNE INTO THE CWA BY THU
MORNING. THIS WILL CREATE A DEEP SOUTHERLY FLOW WHICH WILL CONNECT
WITH GULF MOISTURE...ALLOWING FOR SIGNIFICANT RAINFALL...FROM
LATE IN THE DAY WED...INTO EARLY THU MORNING. QPF LOOKS TO RUN
AROUND 2-3 INCHES IN MANY SPOTS...BUT S-SE UPSLOPE AREAS OF THE
FOOTHILLS AND MTNS COULD SEE AN INCH OR TWO MORE...SO THE THREAT
OF BOTH FLASH AND MAINSTEM FLOODING IS A CONCERN...ESPECIALLY
SINCE THIS WILL BE COMBINE WITH SIGNIFICANT SNOWMELT AS HIGHS
RISE WELL INTO THE 40S WED..AND WILL LKLY STAY THERE WED NIGHT
INTO THU.

THERE IS STILL THE POTENTIAL FOR SOME STRONG GUSTS...BUT GIVEN
WEAKER SYSTEM...THE WINDOW FOR OPPORTUNITY WILL BE LIMITED TO A
FE HOURS AHEAD OF THE TRIPLE POINT PASSAGE...WHICH LOOKS TO BE WED
EVE...AT LEAST FOR NOW. WITH ALL THAT SAID...WE ARE STILL DEALING
WITH DAYS 4 AND 5 OF THE FORECAST...WITH THE POTENTIAL FRO SOME
DEEP CONVECTION IN THE BASE OF THE TROUGH...SO FORECAST COULD
CHANGE...BUT BOTH EURO AND GFS PICKED UP THE SIGNALS OF THIS
SYSTEM EARLY...AND HAVE BEEN CONSISTENT ON THE WHOLE SO FAR.

CHRISTMAS DAY WILL SEE RAIN ENDING FROM SW TO NE DURING THE
MORNING...WITH SOME PARTIAL CLEARING POSSIBLE IN THE
AFTERNOON...AND TEMPS IN THE 40S AGAIN. COOLER AIR WILL MOVE IN
FROM THE SW THU NIGHT. FRI AND SAT LOOK MOSTLY DRY /OTHER THAN
POSSIBLE UPSLOPE SHSN ON FRI/. HIGHS WILL CONTINUE TO RUN A FEW
DEGREES ABV NORMAL.


&&

.AVIATION /08Z SUNDAY THROUGH THURSDAY/...
SHORT TERM...MVFR TO IFR CEILINGS WILL REMAIN OVER THE REGION
THROUGH AT LEAST SUNDAY EVENING. CONDITIONS MAY IMPROVE A BIT
SUNDAY NIGHT AS THE ON SHORE FLOW DRIFTING MOISTURE INLAND WILL
GET SHUT OFF. CONDITIONS WILL NOT STAY UP LONG HOWEVER AS THE FLOW
WILL SWITCH BACK TO ON SHORE ON MONDAY BRINGING ANOTHER ROUND OF
MVFR TO IFR CEILINGS.

LONG TERM...POSSIBLE PERIODS OF MVFR TO IFR MONDAY NIGHT AS
INVERTED TROUGH MOVES INLAND. MVFR LIKELY TO HOLD TUESDAY INTO
TUESDAY NIGHT...LOWERING TO IFR LATE TUESDAY NIGHT INTO THURSDAY
MORNING IN RAIN...WITH INCREASING E-SE WINDS WEDNESDAY.

&&

.MARINE...
SHORT TERM...A FEW WIND GUSTS CONTINUE JUST BELOW 25 KTS THIS
AFTERNOON...WITH WAVES 4` OR LOWER...THEREFORE NO FLAGS IN THE
NEAR TERM. WINDS SHOULD CONTINUE TO SLOWLY DECREASE TONIGHT INTO
TOMORROW FROM THE NORTHEAST.

LONG TERM...HIGH PRESSURE WITH LIGHT AND FAIRLY CALM SEAS WILL
PERSIST THROUGH THE PERIOD AND NO FLAGS ARE EXPECTED.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.

&&

$$
KISTNER/CEMPA




000
FXUS61 KBOX 210626
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
123 AM EST SUN DEC 21 2014

.SYNOPSIS...

SCATTERED SNOW/RAIN SHOWERS WILL AFFECT THE REGION THROUGH SUN.
WEAK LOW PRESSURE WILL PASS SOUTH OF NEW ENGLAND BRINGING ANOTHER
PERIOD OF PRECIPITATION MONDAY NIGHT AND TUESDAY. A MUCH STRONGER
STORM PASSING WEST OF NEW ENGLAND WILL BRING HEAVY
RAINFALL...GUSTY WINDS AND COASTAL FLOODING CONCERNS TO THE REGION
WEDNESDAY AND WEDNESDAY NIGHT. DRY BUT VERY WINDY CONDITIONS
FOLLOW FOR CHRISTMAS DAY.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...

120 AM UPDATE...

LIGHT SNOW SHOWERS CONTINUE TO FALL ACROSS INTERIOR SOUTHEAST MA AND
INTO RI VERY EARLY THIS MORNING.  COASTAL FRONT RUNS ROUGHLY FROM
NEAR NEW BEDFORD...TO TAUNTON AND NORTH OF MARSHFIELD THIS MORNING.
PTYPE MAINLY SNOW NORTHWEST OF THIS LINE AND RAIN SOUTHEAST OF THIS
LOCATION.

MEANWHILE...ACROSS THE REST OF THE REGION IT WAS DRY EARLY THIS
MORNING OTHER THAN A FLURRIES.  HOWEVER...APPROACHING SHORTWAVE WILL
MOVE ACROSS CT LATER THIS MORNING.  THIS WILL RESULT IN ENOUGH
FORCING FOR SCATTERED SNOW SHOWERS TO OVERSPREAD NORTHERN CT AND
INTO MUCH OF SOUTHERN MA.  SNOW ACCUMULATIONS THIS MORNING SHOULD
RANGE FROM A COATING TO 2 INCHES ACROSS THE REGION.  WE DID ISSUE A
SPECIAL WEATHER STATEMENT TO HIGHLIGHT THE CONCERN FOR SLIPPERY
TRAVEL.  BULK OF THE ACTION WILL BE SOUTH OF THE PIKE...WHERE BETTER
FORCING RESIDES.  HOWEVER...STILL COULD SEE A FEW SNOW SHOWERS WITH
ACCUMS GENERALLY A DUSTING TO LESS THAN AN INCH ACROSS NORTHERN MA.

PTYPE SHOULD REMAIN WARM ENOUGH FOR RAIN SHOWERS ACROSS MUCH OF
PLYMOUTH COUNTY AND ONTO THE CAPE/ISLANDS THIS MORNING...WITH MAINLY
SNOW SHOWERS NORTH AND WEST.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM MONDAY/...
RAIN/SNOW SHOWERS WILL CONTINUE INTO THE MORNING HOURS...THEN TAPER
OFF AS INVERTED TROUGH PULLS AWAY FROM SOUTHERN NEW ENGLAND AND HIGH
PRESSURE STARTS TO BUILD IN.  MOST LIKELY AREAS FOR CONTINUING
SHOWERS WILL BE ALONG THE IMMEDIATE EAST COAST OF MASSACHUSETTS.

AS THE DAY GOES ON...EXPECT A SLOW DRYING TREND AS HIGH PRESSURE
BUILDS INTO THE REGION.  CLOUDS WILL STICK AROUND WITH TEMPS
GENERALLY IN THE 30S.

&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
BIG PICTURE... SHORTWAVE ENTERING THE PACIFIC NORTHWEST CROSSES THE
ROCKIES OVER THE WEEKEND DRIVEN BY A 160-KNOT JET.  THIS DIGS A
SUBSTANTIAL TROUGH OVER THE PLAINS MONDAY-TUESDAY WHILE PACIFIC HIGH
PRESSURE BUILDS ALONG THE PACIFIC COAST. THIS IN TURN WILL ALLOW AN
UPPER RIDGE TO BUILD ALONG THE ATLANTIC COAST AND SLOWLY SHIFT EAST
OF THE COAST.  THE JET ENERGY WORKS ITS WAY AROUND THE BASE OF THE
PLAINS TROUGH AND MOVES UP THE APPALACHANS MIDWEEK.  THIS SUPPORTS A
TRANSITION OF THE TROUGH TO NEGATIVE TILT AND SLOWER MOVEMENT...WITH
WARM MOIST AIR FOR THE ATLANTIC COAST. THE TROUGH AXIS SWINGS OVER
NEW ENGLAND CHRISTMAS DAY FOLLOWED BY A WEAK RIDGE. ANOTHER
SHORTWAVE MOVES ASHORE FROM THE PACIFIC MIDWEEK AND MOVES ACROSS THE
PLAINS BY THE END OF THE WEEK AND APPROACHES THE NORTHEAST USA
SATURDAY.

THERE IS SOME SPREAD IN DETAILS AMONG THE LONG RANGE MODELS...BUT
ALL SHOW A SIMILAR SCENARIO BOTH FOR THE MIDWEEK SYSTEM AND THE END
OF WEEK SYSTEM.  WE USED A BLEND OF GFS/ECMWF.

THE DAILIES...

SUNDAY NIGHT-MONDAY... HIGH PRESSURE REMAINS NORTH OF THE REGION
BRINGING A MOIST EAST FLOW ACROSS SOUTHERN NEW ENGLAND. UPPER
PATTERN SHOWS WEAK RIDGING AS THE PLAINS TROUGH DIGS...BUT SURFACE
FIELDS SUGGEST A LINGERING INVERTED TROUGH ALONG OR JUST OFFSHORE.
THIS SHOULD MAINTAIN CONSIDERABLE CLOUDS. COULD BE SOME DRIZZLE OR
FLURRIES NEAR THE EAST COAST BUT SUPPORTING LARGE SCALE ASCENT IS
LACKING SO PCPN SHOULD BE LIMITED.

MONDAY NIGHT-TUESDAY... LOW PRESSURE FORMS ALONG A STALLED WARM
FRONT OFF THE MID ATLANTIC COAST. AS THE LOW DEVELOPS...IT BRINGS
AN INCREASED PRESSURE GRADIENT AGAINST HIGH PRESSURE MOVING
THROUGH THE MARITIMES. THE RESULT WILL BE A STRENGTHENING LOW
LEVEL EAST- SOUTHEAST JET. THIS WILL INCREASE THE MOIST INFLOW
OVER SOUTHERN NEW ENGLAND. ALSO...AS THE JET CONVERGES ON THE
INVERTED SURFACE TROUGH IT WILL GENERATE INCREASED LOW LEVEL LIFT
AND INCREASE THE CHANCE OF PCPN. WE WILL HAVE CLOUDS AND CHANCE
POPS. TEMPS IN NORTHWEST MASS WILL BE COLD ENOUGH SO THAT THERE
MAY BE A MIX OF PCPN TYPES DURING THE MORNING.

TUESDAY NIGHT-WEDNESDAY... PLAINS UPPER TROUGH DIGS DEEPER AND MOVES
EAST...PUSHING THE UPPER RIDGE TO OUR EAST. ALSO...THE STRONG UPPER
SOUTHWEST JET MOVES UP OVER THE EASTERN USA. THIS SETUP WILL TAKE
THE PRIMARY SURFACE LOW UP THROUGH THE WESTERN GREAT LAKES.
SECONDARY LOWS FORMING ON THE SYSTEM COLD FRONT WILL MOVE OUT OF THE
GULF OF MEXICO TOWARD THE GREAT LAKES. A SOUTHWEST LOW LEVEL JET
WILL MOVE UP THE ATLANTIC COAST ON WEDNESDAY AND OVER THE TOP OF THE
EAST-SOUTHEAST FLOW AT THE SURFACE. THE RESULT WILL BE PLENTY OF LOW
LEVEL LIFT THE GENERATE PCPN.

PRECIPITABLE WATER VALUES ARE FORECAST TO EXCEED 1.5 INCHES...WHICH
IS 3 STD DEVIATIONS ABOVE NORMAL FOR DECEMBER.  THIS MEANS A LOT OF
WATER AVAILABLE AS PCPN. TEMPERATURE PROFILES WILL BE ABOVE FREEZING
SO PTYPE SHOULD BE RAIN. MODEL QPF SHOWS POTENTIAL RAINFALL OF OVER
2 INCHES. THIS WOULD SUGGEST POTENTIAL URBAN/POOR DRAINAGE FLOODING
ISSUES WEDNESDAY.

STRONG LOW LEVEL WINDS WILL ALSO BE A CONCERN ESPECIALLY WEDNESDAY
NIGHT. THE ECMWF SHOWS EAST-SOUTHEAST WINDS 30-35 KNOTS ALONG HE
EAST MASS COAST AT 1000 MB. THEN WEDNESDAY NIGHT WINDS AT 925 MB
INCREASE TO 60-75 KNOTS AND MOVE ACROSS COASTAL RI AND SOUTHEAST
MASS. STRONG DOWNPOURS MAY OVERCOME THE LOW LEVEL INVERSION AND
BRING STRONG GUSTS OF AT LEAST 30-40 KNOTS ESPECIALLY ALONG THE
SOUTH COAST. A WIND ADVISORY MAY BE NEEDED IN SOME AREAS.

MAINTAINED A LIMITED MENTION OF THUNDER...AS CONVECTIVE PARAMETERS
ARE MARGINAL...SI VALUES WILL BE JUST ABOVE ZERO AND K INDEX WILL BE
IN THE LOW 30S WEDNESDAY NIGHT.

UPPER LOW WILL SWING THE SURFACE COLD FRONT THROUGH SOUTHERN NEW
ENGLAND WEDNESDAY NIGHT. WINDS WILL THEN SHIFT TO WEST AND PCPN
SHOULD COME TO AN END AROUND THE TIME THAT SANTA ARRIVES.

CHRISTMAS DAY... WEST WINDS WILL BRING A DRYING OF THE AIRMASS
DURING THE DAY. SO THE TREND SHOULD BE TO AT LEAST PARTIAL CLEARING.
SUFFICIENT COLD ADVECTION AT ALL LEVELS THURSDAY WILL ALLOW SOME
MIXING.  WINDS IN THE SFC-850 MB LAYER WILL BE 30-40 KNOTS AND
POSSIBLY A LITTLE HIGHER...WHICH WOULD REQUIRE A WIND ADVISORY FOR
MUCH OF THE AREA.

FRIDAY-SATURDAY... WEAK HIGH PRESSURE BUILDS OVER THE AREA FRIDAY
AND BRING A SUNNY DAY. THE NEXT PACIFIC SHORTWAVE APPROACHES
SATURDAY AND SHOULD BRING INCREASING CLOUDS FROM WEST TO EAST ALONG
WITH A CHANCE OF RAIN OR SNOW SHOWERS MAINLY IN THE AFTERNOON AND AT
NIGHT.

&&

.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /TODAY AND TONIGHT/...

TODAY AND TONIGHT...MODERATE CONFIDENCE.  MAINLY MVFR CONDITIONS
SOUTH OF THE MA TURNPIKE WITH BORDERLINE VFR TO MARGINAL MVFR CIGS
NORTH OF THE PIKE THROUGH TONIGHT.  AN AREA OF SNOW SHOWERS WILL
EXPAND MAINLY ACROSS AREAS SOUTH OF THE PIKE THIS MORNING...BUT A
FEW SNOW SHOWERS ARE POSSIBLE IN THE NORTHERN MA.  VSBYS MAY BRIEFLY
DROP TO IFR LEVELS IN NORTHERN CT/RI/SE MA.  PTYPE WILL BE RAIN
SHOWERS ACROSS MOST OF PLYMOUTH COUNTY AND ONTO THE CAPE/ISLANDS WITH
SNOW SHOWERS NORTH AND WEST.  BULK OF PRECIP THIS MORNING...BUT A
FEW LINGERING RAIN/SNOW SHOWERS STILL POSSIBLE THIS AFTERNOON AND
EVENING.

KBOS TERMINAL...MODERATE CONFIDENCE.  A FEW SNOW SHOWERS POSSIBLE
BUT BULK OF ACTIVITY SHOULD BE SOUTH OF THE TERMINAL.

KBDL TERMINAL...MODERATE CONFIDENCE.  PERIOD OF SNOW SHOWERS THIS
MORNING MAY DROP A COATING TO PERHAPS UP TO AN INCH OR TWO OF SNOW.
MVFR CONDITIONS DOMINATE TODAY....BUT A BRIEF PERIOD OF IFR
CONDITIONS ARE POSSIBLE THIS MORNING.

OUTLOOK...MONDAY THROUGH THURSDAY...MODERATE CONFIDENCE

MONDAY...MVFR CIGS CONTINUE IN RI/EASTERN MASS IN MARINE EAST FLOW.
VFR IN THE WEST.

TUESDAY...VFR WITH SCATTERED MVFR IN ANY RAIN/SNOW SHOWERS.

WEDNESDAY...CONDITIONS LOWERING TO IFR IN RAIN/HEAVY RAIN. ISOLATED
THUNDERSTORMS POSSIBLE ESPECIALLY WEDNESDAY NIGHT. EAST-SOUTHEAST
SURFACE WINDS MAY GUST TO 35 KNOTS ALONG THE EAST MASSACHUSETTS
COAST. WINDS AT 2000 FEET AGL WILL REACH 50-60 KNOTS WEDNESDAY
AFTERNOON AND EARLY NIGHT CREATING LOW LEVEL WIND SHEAR CONCERNS.

CHRISTMAS DAY...WEST WIND GUSTING 30-40 KNOTS. CONDITIONS IMPROVING
TO VFR AS THE WIND BRINGS IN COOLER DRIER AIR.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

HIGH CONFIDENCE. HIGH PRESSURE ACROSS QUEBEC WILL RESULT IN
PERSISTENT NORTHEAST WINDS ACROSS THE WATERS THROUGH THE WEEKEND.
WIND GUSTS UP TO 20 KNOTS WITH SEAS BETWEEN 2 AND 4 FEET ARE
EXPECTED FOR MOST WATERS...SO NO HEADLINES PLANNED.

THERE IS A LOW PROBABILITY THAT A BRIEF SURGE OF NORTHEAST WIND
GUSTS NEAR 25 KNOTS WITH MARGINAL 5 FOOT SEAS COULD AFFECT OUR
NORTHERN WATERS LATE TONIGHT INTO SUN MORNING...BUT NOT CONFIDENT
ENOUGH TO ISSUE ANY HEADLINES AT THIS POINT.

OUTLOOK...SUNDAY NIGHT THROUGH THURSDAY...MODERATE CONFIDENCE

SUNDAY NIGHT-MONDAY...EAST TO NORTHEAST WINDS GUSTING AROUND 15
KNOTS OR LESS.  SEAS WILL HOLD AROUND 3-4 FEET.

TUESDAY... INCREASING EAST WINDS WITH FREQUENT GUSTS 25 TO 30 KNOTS.
SEAS WILL BUILD TO 5-6 FEET ON THE EXPOSED WATERS.  A SMALL CRAFT
ADVISORY MAY BE NEEDED.

WEDNESDAY...RAIN WILL BE HEAVY AT TIMES PRODUCING POOR VISIBILITY.
INCREASING SOUTHEAST WINDS 20-25 SUSTAINED AND 40 KNOT GUSTS.  WINDS
SHOULD SHIFT TO SOUTH WEDNESDAY NIGHT AND SOUTHWEST TOWARD THURSDAY
MORNING. RAIN WILL TAPER OFF WITH THE WIND SHIFT TO SOUTHWEST. SEAS
WILL CONTINUE TO BUILD WITH 5-10 FEET HEIGHTS ON THE EXPOSED WATERS.
A GALE WARNING MAY BE NEEDED.

CHRISTMAS DAY... WEST SOUTHWEST WINDS WILL CONTINUE TO GUST 35-40
KNOTS...SO A GALE WARNING MAY CONTINUE TO BE NEEDED. SEAS OF 10-15
FEET ARE POSSIBLE ON THE EXPOSED WATERS...AND 5 FEET IS POSSIBLE ON
SOME OF THE NEARSHORE WATERS.

&&

.TIDES/COASTAL FLOODING...
HIGH ASTRONOMICAL TIDES WILL OCCUR
TUESDAY THROUGH THURSDAY. BREAKING IT DOWN...ON TUESDAY HIGH TIDE
AT BOSTON WILL BE 11.6 FT. THERE WILL BE EAST WINDS DURING THIS
HIGH TIDE ALLOWING FOR MINOR SPLASHOVER ALONG THE MASS COAST. IF
WIND GUSTS INCREASE THEN COULD POSSIBLE SEE MINOR COASTAL
FLOODING.

ON WEDNESDAY...WINDS WILL SWITCH TO A MORE SOUTHEASTERLY FLOW DURING
THE DAY AND INCREASE QUICKLY DUE TO THE APPROACHING SYSTEM.
WEDNESDAY AFTERNOON HIGH TIDE IN BOSTON IS 11.7 FT...AND AN
APPRECIABLE EAST OR SOUTHEAST WIND SHOULD PUSH LEVELS HIGHER THAN ON
TUESDAY.  THIS WOULD PROBABLY BE THE BEST CHANCE OF MINOR COASTAL
FLOODING ALONG THE EAST COAST.

THE WEDNESDAY EVENING HIGH TIDE WILL BE A LITTLE LOWER...BUT THE
WIND BECOMES SOUTH WITH 50-60 KNOTS AT 2000 FEET ABOVE THE SURFACE
AVAILABLE TO BE BROUGHT DOWN IN GUSTS. HIGH TIDE IN PROVIDENCE WILL
BE 5.2 FT. MINOR COASTAL FLOODING COULD OCCUR ALONG THE SOUTH
COASTS OF RI AND MASS...AND COULD BE CHANNELED IN NORTH-SOUTH AXIS
BAYS SUCH AS NARRAGANSETT BAY.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...WTB/RLG
NEAR TERM...FRANK
SHORT TERM...RLG
LONG TERM...WTB
AVIATION...FRANK/WTB
MARINE...WTB/RLG
TIDES/COASTAL FLOODING...STAFF



000
FXUS61 KBOX 210220
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
918 PM EST SAT DEC 20 2014

.SYNOPSIS...
SCATTERED SNOW/RAIN SHOWERS WILL AFFECT THE REGION THROUGH SUN.
WEAK LOW PRESSURE WILL PASS SOUTH OF NEW ENGLAND BRINGING ANOTHER
PERIOD OF PRECIPITATION MONDAY NIGHT AND TUESDAY. A MUCH STRONGER
STORM PASSING WEST OF NEW ENGLAND WILL BRING HEAVY
RAINFALL...GUSTY WINDS AND COASTAL FLOODING CONCERNS TO THE REGION
WEDNESDAY AND WEDNESDAY NIGHT. DRY BUT VERY WINDY CONDITIONS
FOLLOW FOR CHRISTMAS DAY.

&&

.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...

915 PM UPDATE...

A RATHER TRICKY FORECAST OVERNIGHT WITH INVERTED TROUGH/COASTAL
FRONT RESULTING IN SOME MESOSCALE PROCESSES.  MAIN BAND OF SNOW THAT
HAS DROPPED A NARROW BAND OF 1 TO 2 INCHES OF SNOW ACROSS PORTIONS
OF BOSTON/S SOUTH SHORE WAS GRADUALLY PRESSING SOUTHWEST THIS
EVENING.  THIS PARTLY IN RESPONSE TO A SUBTLE COASTAL FRONT THAT WAS
ALSO SHIFTING FURTHER WEST INTO PLYMOUTH AND EVEN FAR EASTERN
NORFOLK COUNTY.  MILDER AIR WAS ALSO CAUSING SOME OF THESE AREAS TO
MIX WITH OR CHANGE TO RAIN.

OVERALL...STILL THINK THAT A COATING TO AT MOST 2 INCHES WILL COVER
IT FOR MOST OF SOUTHERN NEW ENGLAND INTO SUNDAY.  WE DID OPT TO
SHIFT THE BEST RISK FOR THE 1 TO 2 INCHES A BIT FURTHER SOUTH AND
WEST BASED ON RADAR RETURNS AND LATEST GUIDANCE.  LOW RISK OF
ISOLATED 3 INCH AMOUNTS REMAINS POSSIBLE.

THE RAIN/SNOW LINE WILL LIKELY HANG OUT ACROSS FAR EASTERN
NORFOLK/PLYMOUTH AND PERHAPS FAR SOUTHEAST BRISTOL COUNTIES.  THE
MODELS MAY BE SLIGHTLY UNDER ESTIMATING THE WESTWARD PUSH OF THIS
LINE...SO SOMETHING TO WATCH BUT DO NOT THINK IT WILL GET MUCH
FURTHER WEST THAN THAT.

FINALLY...SCATTERED SNOW SHOWERS MAY ALSO DEVELOP INTO WESTERN
MA/NORTHERN CONNECTICUT OVERNIGHT INTO SUNDAY MORNING WITH A
APPROACHING SHORTWAVE.  MODEL GUIDANCE DIFFERS ON EXACTLY HOW THIS
WILL UNFOLD...BUT INCREASING EAST TO SOUTHEAST FLOW JUST OFF THE
GROUND SHOULD ALLOW FOR AT LEAST SOME ACTIVITY IN OUR WESTERN ZONES
BY DAYBREAK.

&&

.SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
RAIN/SNOW SHOWERS WILL CONTINUE INTO THE MORNING HOURS...THEN TAPER
OFF AS INVERTED TROUGH PULLS AWAY FROM SOUTHERN NEW ENGLAND AND HIGH
PRESSURE STARTS TO BUILD IN.  MOST LIKELY AREAS FOR CONTINUING
SHOWERS WILL BE ALONG THE IMMEDIATE EAST COAST OF MASSACHUSETTS.

AS THE DAY GOES ON...EXPECT A SLOW DRYING TREND AS HIGH PRESSURE
BUILDS INTO THE REGION.  CLOUDS WILL STICK AROUND WITH TEMPS
GENERALLY IN THE 30S.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
BIG PICTURE... SHORTWAVE ENTERING THE PACIFIC NORTHWEST CROSSES THE
ROCKIES OVER THE WEEKEND DRIVEN BY A 160-KNOT JET.  THIS DIGS A
SUBSTANTIAL TROUGH OVER THE PLAINS MONDAY-TUESDAY WHILE PACIFIC HIGH
PRESSURE BUILDS ALONG THE PACIFIC COAST. THIS IN TURN WILL ALLOW AN
UPPER RIDGE TO BUILD ALONG THE ATLANTIC COAST AND SLOWLY SHIFT EAST
OF THE COAST.  THE JET ENERGY WORKS ITS WAY AROUND THE BASE OF THE
PLAINS TROUGH AND MOVES UP THE APPALACHANS MIDWEEK.  THIS SUPPORTS A
TRANSITION OF THE TROUGH TO NEGATIVE TILT AND SLOWER MOVEMENT...WITH
WARM MOIST AIR FOR THE ATLANTIC COAST. THE TROUGH AXIS SWINGS OVER
NEW ENGLAND CHRISTMAS DAY FOLLOWED BY A WEAK RIDGE. ANOTHER
SHORTWAVE MOVES ASHORE FROM THE PACIFIC MIDWEEK AND MOVES ACROSS THE
PLAINS BY THE END OF THE WEEK AND APPROACHES THE NORTHEAST USA
SATURDAY.

THERE IS SOME SPREAD IN DETAILS AMONG THE LONG RANGE MODELS...BUT
ALL SHOW A SIMILAR SCENARIO BOTH FOR THE MIDWEEK SYSTEM AND THE END
OF WEEK SYSTEM.  WE USED A BLEND OF GFS/ECMWF.

THE DAILIES...

SUNDAY NIGHT-MONDAY... HIGH PRESSURE REMAINS NORTH OF THE REGION
BRINGING A MOIST EAST FLOW ACROSS SOUTHERN NEW ENGLAND. UPPER
PATTERN SHOWS WEAK RIDGING AS THE PLAINS TROUGH DIGS...BUT SURFACE
FIELDS SUGGEST A LINGERING INVERTED TROUGH ALONG OR JUST OFFSHORE.
THIS SHOULD MAINTAIN CONSIDERABLE CLOUDS. COULD BE SOME DRIZZLE OR
FLURRIES NEAR THE EAST COAST BUT SUPPORTING LARGE SCALE ASCENT IS
LACKING SO PCPN SHOULD BE LIMITED.

MONDAY NIGHT-TUESDAY... LOW PRESSURE FORMS ALONG A STALLED WARM
FRONT OFF THE MID ATLANTIC COAST. AS THE LOW DEVELOPS...IT BRINGS
AN INCREASED PRESSURE GRADIENT AGAINST HIGH PRESSURE MOVING
THROUGH THE MARITIMES. THE RESULT WILL BE A STRENGTHENING LOW
LEVEL EAST- SOUTHEAST JET. THIS WILL INCREASE THE MOIST INFLOW
OVER SOUTHERN NEW ENGLAND. ALSO...AS THE JET CONVERGES ON THE
INVERTED SURFACE TROUGH IT WILL GENERATE INCREASED LOW LEVEL LIFT
AND INCREASE THE CHANCE OF PCPN. WE WILL HAVE CLOUDS AND CHANCE
POPS. TEMPS IN NORTHWEST MASS WILL BE COLD ENOUGH SO THAT THERE
MAY BE A MIX OF PCPN TYPES DURING THE MORNING.

TUESDAY NIGHT-WEDNESDAY... PLAINS UPPER TROUGH DIGS DEEPER AND MOVES
EAST...PUSHING THE UPPER RIDGE TO OUR EAST. ALSO...THE STRONG UPPER
SOUTHWEST JET MOVES UP OVER THE EASTERN USA. THIS SETUP WILL TAKE
THE PRIMARY SURFACE LOW UP THROUGH THE WESTERN GREAT LAKES.
SECONDARY LOWS FORMING ON THE SYSTEM COLD FRONT WILL MOVE OUT OF THE
GULF OF MEXICO TOWARD THE GREAT LAKES. A SOUTHWEST LOW LEVEL JET
WILL MOVE UP THE ATLANTIC COAST ON WEDNESDAY AND OVER THE TOP OF THE
EAST-SOUTHEAST FLOW AT THE SURFACE. THE RESULT WILL BE PLENTY OF LOW
LEVEL LIFT THE GENERATE PCPN.

PRECIPITABLE WATER VALUES ARE FORECAST TO EXCEED 1.5 INCHES...WHICH
IS 3 STD DEVIATIONS ABOVE NORMAL FOR DECEMBER.  THIS MEANS A LOT OF
WATER AVAILABLE AS PCPN. TEMPERATURE PROFILES WILL BE ABOVE FREEZING
SO PTYPE SHOULD BE RAIN. MODEL QPF SHOWS POTENTIAL RAINFALL OF OVER
2 INCHES. THIS WOULD SUGGEST POTENTIAL URBAN/POOR DRAINAGE FLOODING
ISSUES WEDNESDAY.

STRONG LOW LEVEL WINDS WILL ALSO BE A CONCERN ESPECIALLY WEDNESDAY
NIGHT. THE ECMWF SHOWS EAST-SOUTHEAST WINDS 30-35 KNOTS ALONG HE
EAST MASS COAST AT 1000 MB. THEN WEDNESDAY NIGHT WINDS AT 925 MB
INCREASE TO 60-75 KNOTS AND MOVE ACROSS COASTAL RI AND SOUTHEAST
MASS. STRONG DOWNPOURS MAY OVERCOME THE LOW LEVEL INVERSION AND
BRING STRONG GUSTS OF AT LEAST 30-40 KNOTS ESPECIALLY ALONG THE
SOUTH COAST. A WIND ADVISORY MAY BE NEEDED IN SOME AREAS.

MAINTAINED A LIMITED MENTION OF THUNDER...AS CONVECTIVE PARAMETERS
ARE MARGINAL...SI VALUES WILL BE JUST ABOVE ZERO AND K INDEX WILL BE
IN THE LOW 30S WEDNESDAY NIGHT.

UPPER LOW WILL SWING THE SURFACE COLD FRONT THROUGH SOUTHERN NEW
ENGLAND WEDNESDAY NIGHT. WINDS WILL THEN SHIFT TO WEST AND PCPN
SHOULD COME TO AN END AROUND THE TIME THAT SANTA ARRIVES.

CHRISTMAS DAY... WEST WINDS WILL BRING A DRYING OF THE AIRMASS
DURING THE DAY. SO THE TREND SHOULD BE TO AT LEAST PARTIAL CLEARING.
SUFFICIENT COLD ADVECTION AT ALL LEVELS THURSDAY WILL ALLOW SOME
MIXING.  WINDS IN THE SFC-850 MB LAYER WILL BE 30-40 KNOTS AND
POSSIBLY A LITTLE HIGHER...WHICH WOULD REQUIRE A WIND ADVISORY FOR
MUCH OF THE AREA.

FRIDAY-SATURDAY... WEAK HIGH PRESSURE BUILDS OVER THE AREA FRIDAY
AND BRING A SUNNY DAY. THE NEXT PACIFIC SHORTWAVE APPROACHES
SATURDAY AND SHOULD BRING INCREASING CLOUDS FROM WEST TO EAST ALONG
WITH A CHANCE OF RAIN OR SNOW SHOWERS MAINLY IN THE AFTERNOON AND AT
NIGHT.

&&

.AVIATION /02Z SUNDAY THROUGH THURSDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH SUNDAY/...

TONIGHT AND SUNDAY...MVFR CIGS/VSBYS IN RAIN/SNOW SHOWERS MOVING
WEST OFF THE OCEAN INTO SOUTHEASTERN MASS. THESE WILL SPREAD
FARTHER WEST INTO RI/CENTRAL MASS/NORTHEAST CT. LOCAL IFR
CIGS/VSBYS POSSIBLE WITH THE STRONGEST SHOWERS.

WINDS ARE ENE ALONG THE IMMEDIATE SOUTHEAST MASS COAST WITH NORTH
TO NORTHWEST WINDS ELSEWHERE. THIS WINDSHIFT MAY NUDGE FARTHER
WEST WITH THE SHOWERS EARLY TONIGHT.

MVFR CIGS MAY REACH THE CT VALLEY LATE TONIGHT BUT LOW CONFIDENCE
ABOUT ANY SIGNIFICANT REDUCTION IN VSBY THERE.

MVFR CIGS WILL LINGER MOST AREA ON SUNDAY. ANY CIGS THAT RISE
ABOVE MVFR SHOULD ONLY REACH AROUND 4000 FEET.

KBOS TERMINAL...MODERATE CONFIDENCE IN TAF. FLURRIES AND SNOW
SHOWERS THROUGH 06Z WITH POTENTIAL FOR WINDSHIFT TO 040 DURING
THIS TIME.

KBDL TERMINAL...MODERATE CONFIDENCE IN TAF.

OUTLOOK...SUNDAY NIGHT THROUGH THURSDAY...MODERATE CONFIDENCE

SUNDAY NIGHT-MONDAY...MVFR CIGS CONTINUE IN RI/EASTERN MASS IN
MARINE EAST FLOW. VFR IN THE WEST.

TUESDAY...VFR WITH SCATTERED MVFR IN ANY RAIN/SNOW SHOWERS.

WEDNESDAY...CONDITIONS LOWERING TO IFR IN RAIN/HEAVY RAIN. ISOLATED
THUNDERSTORMS POSSIBLE ESPECIALLY WEDNESDAY NIGHT. EAST-SOUTHEST
SURFACE WINDS MAY GUST TO 35 KNOTS ALONG THE EAST MASSACHUSETTS
COAST. WINDS AT 2000 FEET AGL WILL REACH 50-60 KNOTS WEDNESDAY
AFTERNOON AND EARLY NIGHT CREATING LOW LEVEL WIND SHEAR CONCERNS.

CHRISTMAS DAY...WEST WIND GUSTING 30-40 KNOTS. CONDITIONS IMPROVING
TO VFR AS THE WIND BRINGS IN COOLER DRIER AIR.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

HIGH CONFIDENCE. HIGH PRESSURE ACROSS QUEBEC WILL RESULT IN
PERSISTENT NORTHEAST WINDS ACROSS THE WATERS THROUGH THE WEEKEND.
WIND GUSTS UP TO 20 KNOTS WITH SEAS BETWEEN 2 AND 4 FEET ARE
EXPECTED FOR MOST WATERS...SO NO HEADLINES PLANNED.

THERE IS A LOW PROBABILITY THAT A BRIEF SURGE OF NORTHEAST WIND
GUSTS NEAR 25 KNOTS WITH MARGINAL 5 FOOT SEAS COULD AFFECT OUR
NORTHERN WATERS LATE TONIGHT INTO SUN MORNING...BUT NOT CONFIDENT
ENOUGH TO ISSUE ANY HEADLINES AT THIS POINT.

OUTLOOK...SUNDAY NIGHT THROUGH THURSDAY...MODERATE CONFIDENCE

SUNDAY NIGHT-MONDAY...EAST TO NORTHEAST WINDS GUSTING AROUND 15
KNOTS OR LESS.  SEAS WILL HOLD AROUND 3-4 FEET.

TUESDAY... INCREASING EAST WINDS WITH FREQUENT GUSTS 25 TO 30 KNOTS.
SEAS WILL BUILD TO 5-6 FEET ON THE EXPOSED WATERS.  A SMALL CRAFT
ADVISORY MAY BE NEEDED.

WEDNESDAY...RAIN WILL BE HEAVY AT TIMES PRODUCING POOR VISIBILITY.
INCREASING SOUTHEAST WINDS 20-25 SUSTAINED AND 40 KNOT GUSTS.  WINDS
SHOULD SHIFT TO SOUTH WEDNESDAY NIGHT AND SOUTHWEST TOWARD THURSDAY
MORNING. RAIN WILL TAPER OFF WITH THE WIND SHIFT TO SOUTHWEST. SEAS
WILL CONTINUE TO BUILD WITH 5-10 FEET HEIGHTS ON THE EXPOSED WATERS.
A GALE WARNING MAY BE NEEDED.

CHRISTMAS DAY... WEST SOUTHWEST WINDS WILL CONTINUE TO GUST 35-40
KNOTS...SO A GALE WARNING MAY CONTINUE TO BE NEEDED. SEAS OF 10-15
FEET ARE POSSIBLE ON THE EXPOSED WATERS...AND 5 FEET IS POSSIBLE ON
SOME OF THE NEARSHORE WATERS.

&&

.TIDES/COASTAL FLOODING...
HIGH ASTRONOMICAL TIDES WILL OCCUR
TUESDAY THROUGH THURSDAY. BREAKING IT DOWN...ON TUESDAY HIGH TIDE
AT BOSTON WILL BE 11.6 FT. THERE WILL BE EAST WINDS DURING THIS
HIGH TIDE ALLOWING FOR MINOR SPLASHOVER ALONG THE MASS COAST. IF
WIND GUSTS INCREASE THEN COULD POSSIBLE SEE MINOR COASTAL
FLOODING.

ON WEDNESDAY...WINDS WILL SWITCH TO A MORE SOUTHEASTERLY FLOW DURING
THE DAY AND INCREASE QUICKLY DUE TO THE APPROACHING SYSTEM.
WEDNESDAY AFTERNOON HIGH TIDE IN BOSTON IS 11.7 FT...AND AN
APPRECIABLE EAST OR SOUTHEAST WIND SHOULD PUSH LEVELS HIGHER THAN ON
TUESDAY.  THIS WOULD PROBABLY BE THE BEST CHACNE OF MINOR COASTAL
FLOODING ALONG THE EAST COAST.

THE WEDNESDAY EVENING HIGH TIDE WILL BE A LITTLE LOWER...BUT THE
WIND BECOMES SOUTH WITH 50-60 KNOTS AT 2000 FEET ABOVE THE SURFACE
AVAILABLE TO BE BROUGHT DOWN IN GUSTS. HIGH TIDE IN PROVIDENCE WILL
BE 5.2 FT. MINOR COASTAL FLOODING COULD OCCUR ALONG THE SOUTH
COASTS OF RI AND MASS...AND COULD BE CHANNELED IN NORTH-SOUTH AXIS
BAYS SUCH AS NARRAGANSETT BAY.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...NONE.

&&

$$ SYNOPSIS...WTB/RLG
NEAR TERM...FRANK
SHORT TERM...RLG
LONG TERM...WTB
AVIATION...WTB/RLG
MARINE...WTB/RLG
TIDES/COASTAL FLOODING...STAFF



000
FXUS61 KGYX 210000
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
700 PM EST SAT DEC 20 2014

.SYNOPSIS...
HIGH PRESSURE BUILDS OVER NORTHERN MAINE SUNDAY...ALLOWING THE
FLOW TO TURN ONSHORE. A WEAK WEATHER DISTURBANCE MAY TRIGGER SOME
FLURRIES OR LIGHT SNOW OVER SOUTHERN REGIONS RIGHT THROUGH MONDAY.
A WEAK AREA OF LOW PRESSURE WILL MOVE UP THE COAST TUESDAY...WITH
A MORE SIGNIFICANT SYSTEM GRADUALLY ORGANIZING WEDNESDAY...BEFORE
MOVING OVER THE GREAT LAKES. THIS COULD BRING WINDY CONDITIONS AND
THE POTENTIAL FOR HEAVY RAIN AROUND CHRISTMAS EVE INTO EARLY
CHRISTMAS MORNING.

&&

.NEAR TERM /TONIGHT/...
7PM UPDATE...
HAVE UPDATED THE FORECAST TO BRING HOURLY TEMPERATURE TRENDS IN
LINE WITH LATEST OBSERVATIONS. HAVE ALSO MADE SOME MINOR
ADJUSTMENTS TO SKY COVER AND POP. TWO AREAS OF CLOUDS ARE
IMPACTING PARTS OF THE FORECAST AREA THIS EVENING AS SURFACE HIGH
PRESSURE SITS OVER NORTHERN NEW ENGLAND AND SOUTHERN QUEBEC. SOME
LOW CLOUDS HAVE MOVED SOUTHWEST ACROSS MUCH OF MAINE AND ARE NOW
IMPACTING AUGUSTA AND LEWISTON AND POINTS EAST. ANOTHER AREA OF
CLOUDS HAS PUSHED WESTWARD OFF THE WATER OVER SOUTHERN NEW ENGLAND
AND INTO THE SOUTHERN HALF OF NEW HAMPSHIRE. SOME LIGHT SNOW
SHOWERS ALSO ARE DRIFTING IN ON THE ONSHORE FLOW OVER
MASSACHUSETTS AND SOME OF THESE SNOW SHOWERS ARE EXPECTED TO MOVE
NORTH INTO SOUTHERN NEW HAMPSHIRE OVERNIGHT. THESE SNOW SHOWERS
ARE PRIMARILY BEING GENERATED FROM THE ONSHORE FLOW OFF THE OCEAN.
ONLY LIGHT ACCUMULATIONS ARE EXPECTED... UP TO ABOUT AN INCH.

ORIGINAL DISCUSSION...
STRATOCUMULUS CONTINUES TO POUR IN OFF THE GULF OF MAINE LATE
THIS AFTERNOON. SCATTERED SNOW SHOWERS WILL REMAIN OFFSHORE FOR A
FEW MORE HOURS PER LATEST RADAR TRENDS. HOWEVER...SOME
PRECIPITATION WILL BEGIN TO ENTER THE SEACOAST OF NH THIS
EVENING. 12Z MESOSCALE MODEL SUITE CONTINUES TO SHOW THESE SNOW
SHOWERS BECOMING PERSISTENT ENOUGH TO DROP A LIGHT COATING OF SNOW
IN THE MANCHESTER THROUGH PORTSMOUTH CORRIDOR.

WITH MAINLY CLEAR SKIES UP NORTH...EXPECT ANOTHER COLD NIGHT WITH
LOWS IN THE SINGLE NUMBERS. SOME AREAS IN THE NORTH WERE BELOW
ZERO THIS MORNING.

&&

.SHORT TERM /SUNDAY AND SUNDAY NIGHT/...
SNOW SHOWERS MAY BE PERSISTENT OVER SOUTHERN NEW HAMPSHIRE EARLY
SUNDAY DUE TO OCEAN EFFECT...WITH DRYING OCCURRING DURING THE
AFTERNOON. THE PASSAGE OF A WEAK UPPER LEVEL LOW OVER EASTERN
AREAS MAY BRING A SNOW SHOWER OR TWO TO THE MIDCOAST AREA OF
MAINE.

SOME CLEARING WILL OCCUR SUNDAY NIGHT AS THE WEAK SYSTEM SHIFTS TO
THE EAST. HOWEVER...A LOW LEVEL NORTHEAST FLOW WILL CONTINUE...WHICH
WILL ALLOW FOR THE POSSIBILITY OF A LIGHT SNOW SHOWER ALONG THE
COAST AND SOME LOW CLOUDINESS. THIS WILL KEEP MINIMUM TEMPERATURES
ALONG THE COAST IN THE MID TO UPPER 20S...WHILE THE MOUNTAINS DROP
OFF INTO THE LOWER TO MIDDLE TEENS.

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...
THE WEAK ONSHORE FLOW CONTINUES MONDAY INTO TUESDAY WITH LOW
LEVEL MOISTURE DEEPEST ALONG THE COAST. SOME PERIODS OF LIGHT SNOW
OR DRIZZLE OR EVEN SOME FREEZING DRIZZLE ARE POSSIBLE MONDAY AND
MONDAY NIGHT. ON TUESDAY THE WARMER ONSHORE FLOW DEEPENS AS THE
HIGH MOVES FURTHER OFFSHORE ALLOWING A SOUTHEAST FLOW TO
INCREASE...SO CANNOT RULE OUT SOME LIGHT INTERMITTENT
PRECIPITATION. THE MAIN EVENT WILL BE THE ONSET OF THE HEAVIER
PRECIPITATION LATE CHRISTMAS EVE AND ESPECIALLY CHRISTMAS DAY AND
NIGHT WHERE THE RAIN WILL BECOME HEAVY AT TIMES AS A STRONG WARM
ADVECTION PATTERN DEVELOPS BEING ACCOMPANIED BY A STRONG LOW/MID
LEVEL JET. THE MAIN UPPER LOW PASSES WELL TO OUR WEST AS IT MOVES
THROUGH THE GREAT LAKES. QPF TOTALS FOR LATE TUESDAY INTO THURSDAY
COULD BE IN THE 2-4 INCH RANGE. DUE TO VERY WARM AIR THIS WILL BE
IN THE FORM OF RAIN EVEN IN THE MOUNTAINS. SOME FLOODING PROBLEMS
MAY ARISE IN THE HEADWATERS BY WEDNESDAY NIGHT OR THURSDAY DUE TO
THE COMBINATION OF SNOWMELT AND THE HEAVY RAINS. ALL MODELS AGREE
ON MILD TEMPERATURES...USED A BLEND OF THE MODELS.

SYSTEM FINALLY WINDS DOWN BY THURSDAY AFTERNOON AS A DRY SLOT
MOVES ACROSS THE AREA.

ANOTHER SYSTEM WHICH WILL BE WEAKER APPROACHES FOR THE WEEKEND
WHICH ALSO LOOKS WARM AND WET.

&&

.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
SHORT TERM...IFR CLOUD DECK IS ADVANCING SOUTHWEST ACROSS MUCH OF
MAINE THIS EVENING. THIS WILL PRIMARILY IMPACT AUGUSTA AND
ROCKLAND BUT COULD IMPACT PORTLAND AS WELL. ANOTHER AREA OF
MVFR/VFR CLOUDS ARE IMPACTING SOUTHERN NEW HAMPSHIRE AND MAY LOWER
A BIT INTO THE MVFR TO IFR RANGE OVERNIGHT. SOME LIGHT SNOW
SHOWERS ARE ALSO POSSIBLE ACROSS SOUTHERN NEW HAMPSHIRE INCLUDING
AT PORTSMOUTH AND MANCHESTER OVERNIGHT INTO SUNDAY MORNING.

LONG TERM...POSSIBLE PERIODS OF MVFR TO IFR AT COASTAL TERMINALS
MONDAY AS INVERTED TROUGH DEVELOPS ACROSS THE GULF OF MAINE. MVFR
LIKELY TO HOLD TUESDAY INTO TUESDAY NIGHT...LOWERING TO IFR LATE
TUESDAY NIGHT INTO THURSDAY IN RAIN...WITH INCREASING E-SE WINDS
WEDNESDAY.

&&

.MARINE...
SHORT TERM...A FEW WIND GUSTS CONTINUE JUST BELOW 25 KTS THIS
AFTERNOON...WITH WAVES 4` OR LOWER...THEREFORE NO FLAGS IN THE
NEAR TERM. WINDS SHOULD CONTINUE TO SLOWLY DECREASE TONIGHT INTO
TOMORROW FROM THE NORTHEAST.

LONG TERM...STRONG LOW PRESSURE WILL MOVE WELL TO THE WEST AND
WILL CAUSE WINDS TO INCREASE TO GALES TUESDAY NIGHT THROUGH
WEDNESDAY WITH BORDERLINE STORM FORCE WINDS POSSIBLE WEDNESDAY
NIGHT. SEAS COULD BUILD IN EXCESS OF 15 FT OVER THE OUTER WATERS
BY WEDNESDAY NIGHT. GUIDANCE LOOKS LOW ON BOTH WINDS AND SEAS
WHICH IS TYPICAL FOR THESE TYPE OF EVENTS.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.

&&

$$

NEAR TERM UPDATE... KIMBLE



000
FXUS61 KGYX 210000
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
700 PM EST SAT DEC 20 2014

.SYNOPSIS...
HIGH PRESSURE BUILDS OVER NORTHERN MAINE SUNDAY...ALLOWING THE
FLOW TO TURN ONSHORE. A WEAK WEATHER DISTURBANCE MAY TRIGGER SOME
FLURRIES OR LIGHT SNOW OVER SOUTHERN REGIONS RIGHT THROUGH MONDAY.
A WEAK AREA OF LOW PRESSURE WILL MOVE UP THE COAST TUESDAY...WITH
A MORE SIGNIFICANT SYSTEM GRADUALLY ORGANIZING WEDNESDAY...BEFORE
MOVING OVER THE GREAT LAKES. THIS COULD BRING WINDY CONDITIONS AND
THE POTENTIAL FOR HEAVY RAIN AROUND CHRISTMAS EVE INTO EARLY
CHRISTMAS MORNING.

&&

.NEAR TERM /TONIGHT/...
7PM UPDATE...
HAVE UPDATED THE FORECAST TO BRING HOURLY TEMPERATURE TRENDS IN
LINE WITH LATEST OBSERVATIONS. HAVE ALSO MADE SOME MINOR
ADJUSTMENTS TO SKY COVER AND POP. TWO AREAS OF CLOUDS ARE
IMPACTING PARTS OF THE FORECAST AREA THIS EVENING AS SURFACE HIGH
PRESSURE SITS OVER NORTHERN NEW ENGLAND AND SOUTHERN QUEBEC. SOME
LOW CLOUDS HAVE MOVED SOUTHWEST ACROSS MUCH OF MAINE AND ARE NOW
IMPACTING AUGUSTA AND LEWISTON AND POINTS EAST. ANOTHER AREA OF
CLOUDS HAS PUSHED WESTWARD OFF THE WATER OVER SOUTHERN NEW ENGLAND
AND INTO THE SOUTHERN HALF OF NEW HAMPSHIRE. SOME LIGHT SNOW
SHOWERS ALSO ARE DRIFTING IN ON THE ONSHORE FLOW OVER
MASSACHUSETTS AND SOME OF THESE SNOW SHOWERS ARE EXPECTED TO MOVE
NORTH INTO SOUTHERN NEW HAMPSHIRE OVERNIGHT. THESE SNOW SHOWERS
ARE PRIMARILY BEING GENERATED FROM THE ONSHORE FLOW OFF THE OCEAN.
ONLY LIGHT ACCUMULATIONS ARE EXPECTED... UP TO ABOUT AN INCH.

ORIGINAL DISCUSSION...
STRATOCUMULUS CONTINUES TO POUR IN OFF THE GULF OF MAINE LATE
THIS AFTERNOON. SCATTERED SNOW SHOWERS WILL REMAIN OFFSHORE FOR A
FEW MORE HOURS PER LATEST RADAR TRENDS. HOWEVER...SOME
PRECIPITATION WILL BEGIN TO ENTER THE SEACOAST OF NH THIS
EVENING. 12Z MESOSCALE MODEL SUITE CONTINUES TO SHOW THESE SNOW
SHOWERS BECOMING PERSISTENT ENOUGH TO DROP A LIGHT COATING OF SNOW
IN THE MANCHESTER THROUGH PORTSMOUTH CORRIDOR.

WITH MAINLY CLEAR SKIES UP NORTH...EXPECT ANOTHER COLD NIGHT WITH
LOWS IN THE SINGLE NUMBERS. SOME AREAS IN THE NORTH WERE BELOW
ZERO THIS MORNING.

&&

.SHORT TERM /SUNDAY AND SUNDAY NIGHT/...
SNOW SHOWERS MAY BE PERSISTENT OVER SOUTHERN NEW HAMPSHIRE EARLY
SUNDAY DUE TO OCEAN EFFECT...WITH DRYING OCCURRING DURING THE
AFTERNOON. THE PASSAGE OF A WEAK UPPER LEVEL LOW OVER EASTERN
AREAS MAY BRING A SNOW SHOWER OR TWO TO THE MIDCOAST AREA OF
MAINE.

SOME CLEARING WILL OCCUR SUNDAY NIGHT AS THE WEAK SYSTEM SHIFTS TO
THE EAST. HOWEVER...A LOW LEVEL NORTHEAST FLOW WILL CONTINUE...WHICH
WILL ALLOW FOR THE POSSIBILITY OF A LIGHT SNOW SHOWER ALONG THE
COAST AND SOME LOW CLOUDINESS. THIS WILL KEEP MINIMUM TEMPERATURES
ALONG THE COAST IN THE MID TO UPPER 20S...WHILE THE MOUNTAINS DROP
OFF INTO THE LOWER TO MIDDLE TEENS.

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...
THE WEAK ONSHORE FLOW CONTINUES MONDAY INTO TUESDAY WITH LOW
LEVEL MOISTURE DEEPEST ALONG THE COAST. SOME PERIODS OF LIGHT SNOW
OR DRIZZLE OR EVEN SOME FREEZING DRIZZLE ARE POSSIBLE MONDAY AND
MONDAY NIGHT. ON TUESDAY THE WARMER ONSHORE FLOW DEEPENS AS THE
HIGH MOVES FURTHER OFFSHORE ALLOWING A SOUTHEAST FLOW TO
INCREASE...SO CANNOT RULE OUT SOME LIGHT INTERMITTENT
PRECIPITATION. THE MAIN EVENT WILL BE THE ONSET OF THE HEAVIER
PRECIPITATION LATE CHRISTMAS EVE AND ESPECIALLY CHRISTMAS DAY AND
NIGHT WHERE THE RAIN WILL BECOME HEAVY AT TIMES AS A STRONG WARM
ADVECTION PATTERN DEVELOPS BEING ACCOMPANIED BY A STRONG LOW/MID
LEVEL JET. THE MAIN UPPER LOW PASSES WELL TO OUR WEST AS IT MOVES
THROUGH THE GREAT LAKES. QPF TOTALS FOR LATE TUESDAY INTO THURSDAY
COULD BE IN THE 2-4 INCH RANGE. DUE TO VERY WARM AIR THIS WILL BE
IN THE FORM OF RAIN EVEN IN THE MOUNTAINS. SOME FLOODING PROBLEMS
MAY ARISE IN THE HEADWATERS BY WEDNESDAY NIGHT OR THURSDAY DUE TO
THE COMBINATION OF SNOWMELT AND THE HEAVY RAINS. ALL MODELS AGREE
ON MILD TEMPERATURES...USED A BLEND OF THE MODELS.

SYSTEM FINALLY WINDS DOWN BY THURSDAY AFTERNOON AS A DRY SLOT
MOVES ACROSS THE AREA.

ANOTHER SYSTEM WHICH WILL BE WEAKER APPROACHES FOR THE WEEKEND
WHICH ALSO LOOKS WARM AND WET.

&&

.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
SHORT TERM...IFR CLOUD DECK IS ADVANCING SOUTHWEST ACROSS MUCH OF
MAINE THIS EVENING. THIS WILL PRIMARILY IMPACT AUGUSTA AND
ROCKLAND BUT COULD IMPACT PORTLAND AS WELL. ANOTHER AREA OF
MVFR/VFR CLOUDS ARE IMPACTING SOUTHERN NEW HAMPSHIRE AND MAY LOWER
A BIT INTO THE MVFR TO IFR RANGE OVERNIGHT. SOME LIGHT SNOW
SHOWERS ARE ALSO POSSIBLE ACROSS SOUTHERN NEW HAMPSHIRE INCLUDING
AT PORTSMOUTH AND MANCHESTER OVERNIGHT INTO SUNDAY MORNING.

LONG TERM...POSSIBLE PERIODS OF MVFR TO IFR AT COASTAL TERMINALS
MONDAY AS INVERTED TROUGH DEVELOPS ACROSS THE GULF OF MAINE. MVFR
LIKELY TO HOLD TUESDAY INTO TUESDAY NIGHT...LOWERING TO IFR LATE
TUESDAY NIGHT INTO THURSDAY IN RAIN...WITH INCREASING E-SE WINDS
WEDNESDAY.

&&

.MARINE...
SHORT TERM...A FEW WIND GUSTS CONTINUE JUST BELOW 25 KTS THIS
AFTERNOON...WITH WAVES 4` OR LOWER...THEREFORE NO FLAGS IN THE
NEAR TERM. WINDS SHOULD CONTINUE TO SLOWLY DECREASE TONIGHT INTO
TOMORROW FROM THE NORTHEAST.

LONG TERM...STRONG LOW PRESSURE WILL MOVE WELL TO THE WEST AND
WILL CAUSE WINDS TO INCREASE TO GALES TUESDAY NIGHT THROUGH
WEDNESDAY WITH BORDERLINE STORM FORCE WINDS POSSIBLE WEDNESDAY
NIGHT. SEAS COULD BUILD IN EXCESS OF 15 FT OVER THE OUTER WATERS
BY WEDNESDAY NIGHT. GUIDANCE LOOKS LOW ON BOTH WINDS AND SEAS
WHICH IS TYPICAL FOR THESE TYPE OF EVENTS.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.

&&

$$

NEAR TERM UPDATE... KIMBLE




000
FXUS61 KBOX 202357
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
657 PM EST SAT DEC 20 2014

.SYNOPSIS...
SCATTERED SNOW/RAIN SHOWERS WILL AFFECT THE REGION THROUGH SUN.
WEAK LOW PRESSURE WILL PASS SOUTH OF NEW ENGLAND BRINGING ANOTHER
PERIOD OF PRECIPITATION MONDAY NIGHT AND TUESDAY. A MUCH STRONGER
STORM PASSING WEST OF NEW ENGLAND WILL BRING HEAVY
RAINFALL...GUSTY WINDS AND COASTAL FLOODING CONCERNS TO THE REGION
WEDNESDAY AND WEDNESDAY NIGHT. DRY BUT VERY WINDY CONDITIONS
FOLLOW FOR CHRISTMAS DAY.

&&

.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...

630 PM UPDATE...
COASTAL BOUNDARY ALONG EAST COASTAL MASS. WINDS ARE EAST-NORTHEAST
AT MARSHFIELD...HYANNIS AND PROVINCETOWN. WINDS ARE NORTH TO
NORTHWEST AT BOSTON...PLYMOUTH AIRPORT...OTIS ANG BASE. DEWPOINTS
ARE IN THE 30S EAST OF THE BOUNDARY AND 20S TO THE WEST. THE
CONVERGENCE ALONG THIS LINE AND MOIST INFLOW OFF THE OCEAN ARE
SERVING TO MAINTAIN RAIN/SNOW SHOWERS FROM SOUTH BOSTON TO THE
CAPE AND ISLANDS. THE WHOLE AREA IS MOVING WEST AND WILL MOVE
ACROSS THE REMAINDER OF SOUTHEAST MASS AND RI EARLY TONIGHT.

REPORT OF SNOW AT BEVERLY MASS EARLIER THIS EVENING. THERE WASN/T
MUCH TO SPEAK OF ON THE BOX RADAR...BUT TERMINAL DOPPLER A FEW
MILES FARTHER NORTH WAS ABLE TO SEE SOME LIGHT ECHOES AT THE TIME.
THESE HAVE SINCE DISSIPATED.

WE HAVE KEPT THE FORECAST MOSTLY INTACT FROM 4 PM. THE MOIST FLOW
WILL KEEP CLOUDS OVERHEAD. RAIN/SNOW SHOWERS SOUTH OF BOSTON WILL
SPREAD WEST OVERNIGHT. LINGERING CHANCE THAT ADDITIONAL SNOW
SHOWERS MOVE ASHORE THROUGH ESSEX COUNTY LATER IN THE NIGHT BUT
LOW CONFIDENCE ON THAT. ALSO LOW CONFIDENCE ON HOW MUCH REACHES
THE CT VALLEY.

PREVIOUS DISCUSSION...
AN INVERTED TROUGH WILL DEVELOP THIS EVENING IN RESPONSE TO A
SHORTWAVE MOVING ACROSS SOUTHERN NEW ENGLAND.  THIS WILL PROVIDE A
FOCUS FOR RAIN/SNOW SHOWERS ACROSS MUCH OF EASTERN MASSACHUSETTS
BEGINNING THIS AFTERNOON AND CONTINUING THROUGH TONIGHT.  WHILE SNOW
SHOWERS MAY REACH INTO WESTERN NEW ENGLAND TONIGHT...A COASTAL FRONT
WILL DEVELOP...AIDING IN FOCUSING SHOWERS ALONG THE EAST COAST OF
MASSACHUSETTS.

SNOW SHOWERS WILL BECOME MORE WIDESPREAD TONIGHT AS THE LOW LEVELS
MOISTEN UP A BIT MORE. LOOKS LIKE IT WILL LIKELY BE WARM ENOUGH
ACROSS THE CAPE AND SOUTHEASTERN PLYMOUTH COUNTY FOR SHOWERS TO BE
RAIN RATHER THAN SNOW.

OVERALL...EXPECTING 1-2 INCHES OF SNOW AT MOST ACROSS EASTERN
MASSACHUSETTS AND RHODE ISLAND.  THERE ARE SEVERAL POTENTIAL PLACES
WHERE LOCALIZED SLIGHTLY HIGHER AMOUNTS /POSSIBLY UP TO 2-4 INCHES/
ARE POSSIBLE.  LOOKING AT THE HIGH RES MODELS...EITHER ACROSS ESSEX
COUNTY AND CAPE ANN...EASTERN NORFOLK COUNTY INTO NORTHERN PLYMOUTH
COUNTY...OR BOTH. THEN THE HIGHER TERRAIN OF WORCESTER COUNTY AND
PROVIDENCE COUNTY MAY SEE SLIGHTLY HIGHER AMOUNTS GIVEN THE UPSLOPE
COMPONENT OF THE WINDS.

SOME OF THE HIGH RES MODELS HAVE A DECENT CLIP OF QPF INTO ESSEX
COUNTY...WHILE OTHERS HAVE NOTHING IN THE SAME AREA.  FOR NORFOLK
AND PLYMOUTH COUNTY...WE MAY SEE A BIT OF OCEAN ENHANCEMENT THAT
RAISES SNOW AMOUNTS IN THOSE AREAS.  DUE TO THE UNCERTAINTY AND THE
LOCALIZED NATURE OF THE POTENTIAL HIGHER AMOUNTS...AM OPTING NOT TO
ISSUE A WINTER WEATHER ADVISORY. INSTEAD...REISSUED THE SPECIAL
WEATHER STATEMENT FOR SNOW. ANYONE OUT AND ABOUT THIS EVENING IN
EASTERN MASSACHUSETTS WILL WANT TO USE CAUTION AS THERE MAY BE
SLIPPERY PATCHES.

&&

.SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
RAIN/SNOW SHOWERS WILL CONTINUE INTO THE MORNING HOURS...THEN TAPER
OFF AS INVERTED TROUGH PULLS AWAY FROM SOUTHERN NEW ENGLAND AND HIGH
PRESSURE STARTS TO BUILD IN.  MOST LIKELY AREAS FOR CONTINUING
SHOWERS WILL BE ALONG THE IMMEDIATE EAST COAST OF MASSACHUSETTS.

AS THE DAY GOES ON...EXPECT A SLOW DRYING TREND AS HIGH PRESSURE
BUILDS INTO THE REGION.  CLOUDS WILL STICK AROUND WITH TEMPS
GENERALLY IN THE 30S.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
BIG PICTURE... SHORTWAVE ENTERING THE PACIFIC NORTHWEST CROSSES THE
ROCKIES OVER THE WEEKEND DRIVEN BY A 160-KNOT JET.  THIS DIGS A
SUBSTANTIAL TROUGH OVER THE PLAINS MONDAY-TUESDAY WHILE PACIFIC HIGH
PRESSURE BUILDS ALONG THE PACIFIC COAST. THIS IN TURN WILL ALLOW AN
UPPER RIDGE TO BUILD ALONG THE ATLANTIC COAST AND SLOWLY SHIFT EAST
OF THE COAST.  THE JET ENERGY WORKS ITS WAY AROUND THE BASE OF THE
PLAINS TROUGH AND MOVES UP THE APPALACHANS MIDWEEK.  THIS SUPPORTS A
TRANSITION OF THE TROUGH TO NEGATIVE TILT AND SLOWER MOVEMENT...WITH
WARM MOIST AIR FOR THE ATLANTIC COAST. THE TROUGH AXIS SWINGS OVER
NEW ENGLAND CHRISTMAS DAY FOLLOWED BY A WEAK RIDGE. ANOTHER
SHORTWAVE MOVES ASHORE FROM THE PACIFIC MIDWEEK AND MOVES ACROSS THE
PLAINS BY THE END OF THE WEEK AND APPROACHES THE NORTHEAST USA
SATURDAY.

THERE IS SOME SPREAD IN DETAILS AMONG THE LONG RANGE MODELS...BUT
ALL SHOW A SIMILAR SCENARIO BOTH FOR THE MIDWEEK SYSTEM AND THE END
OF WEEK SYSTEM.  WE USED A BLEND OF GFS/ECMWF.

THE DAILIES...

SUNDAY NIGHT-MONDAY... HIGH PRESSURE REMAINS NORTH OF THE REGION
BRINGING A MOIST EAST FLOW ACROSS SOUTHERN NEW ENGLAND. UPPER
PATTERN SHOWS WEAK RIDGING AS THE PLAINS TROUGH DIGS...BUT SURFACE
FIELDS SUGGEST A LINGERING INVERTED TROUGH ALONG OR JUST OFFSHORE.
THIS SHOULD MAINTAIN CONSIDERABLE CLOUDS. COULD BE SOME DRIZZLE OR
FLURRIES NEAR THE EAST COAST BUT SUPPORTING LARGE SCALE ASCENT IS
LACKING SO PCPN SHOULD BE LIMITED.

MONDAY NIGHT-TUESDAY... LOW PRESSURE FORMS ALONG A STALLED WARM
FRONT OFF THE MID ATLANTIC COAST. AS THE LOW DEVELOPS...IT BRINGS
AN INCREASED PRESSURE GRADIENT AGAINST HIGH PRESSURE MOVING
THROUGH THE MARITIMES. THE RESULT WILL BE A STRENGTHENING LOW
LEVEL EAST- SOUTHEAST JET. THIS WILL INCREASE THE MOIST INFLOW
OVER SOUTHERN NEW ENGLAND. ALSO...AS THE JET CONVERGES ON THE
INVERTED SURFACE TROUGH IT WILL GENERATE INCREASED LOW LEVEL LIFT
AND INCREASE THE CHANCE OF PCPN. WE WILL HAVE CLOUDS AND CHANCE
POPS. TEMPS IN NORTHWEST MASS WILL BE COLD ENOUGH SO THAT THERE
MAY BE A MIX OF PCPN TYPES DURING THE MORNING.

TUESDAY NIGHT-WEDNESDAY... PLAINS UPPER TROUGH DIGS DEEPER AND MOVES
EAST...PUSHING THE UPPER RIDGE TO OUR EAST. ALSO...THE STRONG UPPER
SOUTHWEST JET MOVES UP OVER THE EASTERN USA. THIS SETUP WILL TAKE
THE PRIMARY SURFACE LOW UP THROUGH THE WESTERN GREAT LAKES.
SECONDARY LOWS FORMING ON THE SYSTEM COLD FRONT WILL MOVE OUT OF THE
GULF OF MEXICO TOWARD THE GREAT LAKES. A SOUTHWEST LOW LEVEL JET
WILL MOVE UP THE ATLANTIC COAST ON WEDNESDAY AND OVER THE TOP OF THE
EAST-SOUTHEAST FLOW AT THE SURFACE. THE RESULT WILL BE PLENTY OF LOW
LEVEL LIFT THE GENERATE PCPN.

PRECIPITABLE WATER VALUES ARE FORECAST TO EXCEED 1.5 INCHES...WHICH
IS 3 STD DEVIATIONS ABOVE NORMAL FOR DECEMBER.  THIS MEANS A LOT OF
WATER AVAILABLE AS PCPN. TEMPERATURE PROFILES WILL BE ABOVE FREEZING
SO PTYPE SHOULD BE RAIN. MODEL QPF SHOWS POTENTIAL RAINFALL OF OVER
2 INCHES. THIS WOULD SUGGEST POTENTIAL URBAN/POOR DRAINAGE FLOODING
ISSUES WEDNESDAY.

STRONG LOW LEVEL WINDS WILL ALSO BE A CONCERN ESPECIALLY WEDNESDAY
NIGHT. THE ECMWF SHOWS EAST-SOUTHEAST WINDS 30-35 KNOTS ALONG HE
EAST MASS COAST AT 1000 MB. THEN WEDNESDAY NIGHT WINDS AT 925 MB
INCREASE TO 60-75 KNOTS AND MOVE ACROSS COASTAL RI AND SOUTHEAST
MASS. STRONG DOWNPOURS MAY OVERCOME THE LOW LEVEL INVERSION AND
BRING STRONG GUSTS OF AT LEAST 30-40 KNOTS ESPECIALLY ALONG THE
SOUTH COAST. A WIND ADVISORY MAY BE NEEDED IN SOME AREAS.

MAINTAINED A LIMITED MENTION OF THUNDER...AS CONVECTIVE PARAMETERS
ARE MARGINAL...SI VALUES WILL BE JUST ABOVE ZERO AND K INDEX WILL BE
IN THE LOW 30S WEDNESDAY NIGHT.

UPPER LOW WILL SWING THE SURFACE COLD FRONT THROUGH SOUTHERN NEW
ENGLAND WEDNESDAY NIGHT. WINDS WILL THEN SHIFT TO WEST AND PCPN
SHOULD COME TO AN END AROUND THE TIME THAT SANTA ARRIVES.

CHRISTMAS DAY... WEST WINDS WILL BRING A DRYING OF THE AIRMASS
DURING THE DAY. SO THE TREND SHOULD BE TO AT LEAST PARTIAL CLEARING.
SUFFICIENT COLD ADVECTION AT ALL LEVELS THURSDAY WILL ALLOW SOME
MIXING.  WINDS IN THE SFC-850 MB LAYER WILL BE 30-40 KNOTS AND
POSSIBLY A LITTLE HIGHER...WHICH WOULD REQUIRE A WIND ADVISORY FOR
MUCH OF THE AREA.

FRIDAY-SATURDAY... WEAK HIGH PRESSURE BUILDS OVER THE AREA FRIDAY
AND BRING A SUNNY DAY. THE NEXT PACIFIC SHORTWAVE APPROACHES
SATURDAY AND SHOULD BRING INCREASING CLOUDS FROM WEST TO EAST ALONG
WITH A CHANCE OF RAIN OR SNOW SHOWERS MAINLY IN THE AFTERNOON AND AT
NIGHT.

&&

.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH SUNDAY/...

TONIGHT AND SUNDAY...MVFR CIGS/VSBYS IN RAIN/SNOW SHOWERS MOVING
WEST OFF THE OCEAN INTO SOUTHEASTERN MASS. THESE WILL SPREAD
FARTHER WEST INTO RI/CENTRAL MASS/NORTHEAST CT. LOCAL IFR
CIGS/VSBYS POSSIBLE WITH THE STRONGEST SHOWERS.

WINDS ARE ENE ALONG THE IMMEDIATE SOUTHEAST MASS COAST WITH NORTH
TO NORTHWEST WINDS ELSEWHERE. THIS WINDSHIFT MAY NUDGE FARTHER
WEST WITH THE SHOWERS EARLY TONIGHT.

MVFR CIGS MAY REACH THE CT VALLEY LATE TONIGHT BUT LOW CONFIDENCE
ABOUT ANY SIGNIFICANT REDUCTION IN VSBY THERE.

MVFR CIGS WILL LINGER MOST AREA ON SUNDAY. ANY CIGS THAT RISE
ABOVE MVFR SHOULD ONLY REACH AROUND 4000 FEET.

KBOS TERMINAL...MODERATE CONFIDENCE IN TAF. FLURRIES AND SNOW
SHOWERS THROUGH 06Z WITH POTENTIAL FOR WINDSHIFT TO 040 DURING
THIS TIME.

KBDL TERMINAL...MODERATE CONFIDENCE IN TAF.

OUTLOOK...SUNDAY NIGHT THROUGH THURSDAY...MODERATE CONFIDENCE

SUNDAY NIGHT-MONDAY...MVFR CIGS CONTINUE IN RI/EASTERN MASS IN
MARINE EAST FLOW. VFR IN THE WEST.

TUESDAY...VFR WITH SCATTERED MVFR IN ANY RAIN/SNOW SHOWERS.

WEDNESDAY...CONDITIONS LOWERING TO IFR IN RAIN/HEAVY RAIN. ISOLATED
THUNDERSTORMS POSSIBLE ESPECIALLY WEDNESDAY NIGHT. EAST-SOUTHEST
SURFACE WINDS MAY GUST TO 35 KNOTS ALONG THE EAST MASSACHUSETTS
COAST. WINDS AT 2000 FEET AGL WILL REACH 50-60 KNOTS WEDNESDAY
AFTERNOON AND EARLY NIGHT CREATING LOW LEVEL WIND SHEAR CONCERNS.

CHRISTMAS DAY...WEST WIND GUSTING 30-40 KNOTS. CONDITIONS IMPROVING
TO VFR AS THE WIND BRINGS IN COOLER DRIER AIR.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

HIGH CONFIDENCE. HIGH PRESSURE ACROSS QUEBEC WILL RESULT IN
PERSISTENT NORTHEAST WINDS ACROSS THE WATERS THROUGH THE WEEKEND.
WIND GUSTS UP TO 20 KNOTS WITH SEAS BETWEEN 2 AND 4 FEET ARE
EXPECTED FOR MOST WATERS...SO NO HEADLINES PLANNED.

THERE IS A LOW PROBABILITY THAT A BRIEF SURGE OF NORTHEAST WIND
GUSTS NEAR 25 KNOTS WITH MARGINAL 5 FOOT SEAS COULD AFFECT OUR
NORTHERN WATERS LATE TONIGHT INTO SUN MORNING...BUT NOT CONFIDENT
ENOUGH TO ISSUE ANY HEADLINES AT THIS POINT.

OUTLOOK...SUNDAY NIGHT THROUGH THURSDAY...MODERATE CONFIDENCE

SUNDAY NIGHT-MONDAY...EAST TO NORTHEAST WINDS GUSTING AROUND 15
KNOTS OR LESS.  SEAS WILL HOLD AROUND 3-4 FEET.

TUESDAY... INCREASING EAST WINDS WITH FREQUENT GUSTS 25 TO 30 KNOTS.
SEAS WILL BUILD TO 5-6 FEET ON THE EXPOSED WATERS.  A SMALL CRAFT
ADVISORY MAY BE NEEDED.

WEDNESDAY...RAIN WILL BE HEAVY AT TIMES PRODUCING POOR VISIBILITY.
INCREASING SOUTHEAST WINDS 20-25 SUSTAINED AND 40 KNOT GUSTS.  WINDS
SHOULD SHIFT TO SOUTH WEDNESDAY NIGHT AND SOUTHWEST TOWARD THURSDAY
MORNING. RAIN WILL TAPER OFF WITH THE WIND SHIFT TO SOUTHWEST. SEAS
WILL CONTINUE TO BUILD WITH 5-10 FEET HEIGHTS ON THE EXPOSED WATERS.
A GALE WARNING MAY BE NEEDED.

CHRISTMAS DAY... WEST SOUTHWEST WINDS WILL CONTINUE TO GUST 35-40
KNOTS...SO A GALE WARNING MAY CONTINUE TO BE NEEDED. SEAS OF 10-15
FEET ARE POSSIBLE ON THE EXPOSED WATERS...AND 5 FEET IS POSSIBLE ON
SOME OF THE NEARSHORE WATERS.

&&

.TIDES/COASTAL FLOODING...
HIGH ASTRONOMICAL TIDES WILL OCCUR
TUESDAY THROUGH THURSDAY. BREAKING IT DOWN...ON TUESDAY HIGH TIDE
AT BOSTON WILL BE 11.6 FT. THERE WILL BE EAST WINDS DURING THIS
HIGH TIDE ALLOWING FOR MINOR SPLASHOVER ALONG THE MASS COAST. IF
WIND GUSTS INCREASE THEN COULD POSSIBLE SEE MINOR COASTAL
FLOODING.

ON WEDNESDAY...WINDS WILL SWITCH TO A MORE SOUTHEASTERLY FLOW DURING
THE DAY AND INCREASE QUICKLY DUE TO THE APPROACHING SYSTEM.
WEDNESDAY AFTERNOON HIGH TIDE IN BOSTON IS 11.7 FT...AND AN
APPRECIABLE EAST OR SOUTHEAST WIND SHOULD PUSH LEVELS HIGHER THAN ON
TUESDAY.  THIS WOULD PROBABLY BE THE BEST CHACNE OF MINOR COASTAL
FLOODING ALONG THE EAST COAST.

THE WEDNESDAY EVENING HIGH TIDE WILL BE A LITTLE LOWER...BUT THE
WIND BECOMES SOUTH WITH 50-60 KNOTS AT 2000 FEET ABOVE THE SURFACE
AVAILABLE TO BE BROUGHT DOWN IN GUSTS. HIGH TIDE IN PROVIDENCE WILL
BE 5.2 FT. MINOR COASTAL FLOODING COULD OCCUR ALONG THE SOUTH
COASTS OF RI AND MASS...AND COULD BE CHANNELED IN NORTH-SOUTH AXIS
BAYS SUCH AS NARRAGANSETT BAY.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...WTB/RLG
NEAR TERM...WTB/RLG
SHORT TERM...RLG
LONG TERM...WTB
AVIATION...WTB/RLG
MARINE...WTB/RLG
TIDES/COASTAL FLOODING...



000
FXUS61 KBOX 202357
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
657 PM EST SAT DEC 20 2014

.SYNOPSIS...
SCATTERED SNOW/RAIN SHOWERS WILL AFFECT THE REGION THROUGH SUN.
WEAK LOW PRESSURE WILL PASS SOUTH OF NEW ENGLAND BRINGING ANOTHER
PERIOD OF PRECIPITATION MONDAY NIGHT AND TUESDAY. A MUCH STRONGER
STORM PASSING WEST OF NEW ENGLAND WILL BRING HEAVY
RAINFALL...GUSTY WINDS AND COASTAL FLOODING CONCERNS TO THE REGION
WEDNESDAY AND WEDNESDAY NIGHT. DRY BUT VERY WINDY CONDITIONS
FOLLOW FOR CHRISTMAS DAY.

&&

.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...

630 PM UPDATE...
COASTAL BOUNDARY ALONG EAST COASTAL MASS. WINDS ARE EAST-NORTHEAST
AT MARSHFIELD...HYANNIS AND PROVINCETOWN. WINDS ARE NORTH TO
NORTHWEST AT BOSTON...PLYMOUTH AIRPORT...OTIS ANG BASE. DEWPOINTS
ARE IN THE 30S EAST OF THE BOUNDARY AND 20S TO THE WEST. THE
CONVERGENCE ALONG THIS LINE AND MOIST INFLOW OFF THE OCEAN ARE
SERVING TO MAINTAIN RAIN/SNOW SHOWERS FROM SOUTH BOSTON TO THE
CAPE AND ISLANDS. THE WHOLE AREA IS MOVING WEST AND WILL MOVE
ACROSS THE REMAINDER OF SOUTHEAST MASS AND RI EARLY TONIGHT.

REPORT OF SNOW AT BEVERLY MASS EARLIER THIS EVENING. THERE WASN/T
MUCH TO SPEAK OF ON THE BOX RADAR...BUT TERMINAL DOPPLER A FEW
MILES FARTHER NORTH WAS ABLE TO SEE SOME LIGHT ECHOES AT THE TIME.
THESE HAVE SINCE DISSIPATED.

WE HAVE KEPT THE FORECAST MOSTLY INTACT FROM 4 PM. THE MOIST FLOW
WILL KEEP CLOUDS OVERHEAD. RAIN/SNOW SHOWERS SOUTH OF BOSTON WILL
SPREAD WEST OVERNIGHT. LINGERING CHANCE THAT ADDITIONAL SNOW
SHOWERS MOVE ASHORE THROUGH ESSEX COUNTY LATER IN THE NIGHT BUT
LOW CONFIDENCE ON THAT. ALSO LOW CONFIDENCE ON HOW MUCH REACHES
THE CT VALLEY.

PREVIOUS DISCUSSION...
AN INVERTED TROUGH WILL DEVELOP THIS EVENING IN RESPONSE TO A
SHORTWAVE MOVING ACROSS SOUTHERN NEW ENGLAND.  THIS WILL PROVIDE A
FOCUS FOR RAIN/SNOW SHOWERS ACROSS MUCH OF EASTERN MASSACHUSETTS
BEGINNING THIS AFTERNOON AND CONTINUING THROUGH TONIGHT.  WHILE SNOW
SHOWERS MAY REACH INTO WESTERN NEW ENGLAND TONIGHT...A COASTAL FRONT
WILL DEVELOP...AIDING IN FOCUSING SHOWERS ALONG THE EAST COAST OF
MASSACHUSETTS.

SNOW SHOWERS WILL BECOME MORE WIDESPREAD TONIGHT AS THE LOW LEVELS
MOISTEN UP A BIT MORE. LOOKS LIKE IT WILL LIKELY BE WARM ENOUGH
ACROSS THE CAPE AND SOUTHEASTERN PLYMOUTH COUNTY FOR SHOWERS TO BE
RAIN RATHER THAN SNOW.

OVERALL...EXPECTING 1-2 INCHES OF SNOW AT MOST ACROSS EASTERN
MASSACHUSETTS AND RHODE ISLAND.  THERE ARE SEVERAL POTENTIAL PLACES
WHERE LOCALIZED SLIGHTLY HIGHER AMOUNTS /POSSIBLY UP TO 2-4 INCHES/
ARE POSSIBLE.  LOOKING AT THE HIGH RES MODELS...EITHER ACROSS ESSEX
COUNTY AND CAPE ANN...EASTERN NORFOLK COUNTY INTO NORTHERN PLYMOUTH
COUNTY...OR BOTH. THEN THE HIGHER TERRAIN OF WORCESTER COUNTY AND
PROVIDENCE COUNTY MAY SEE SLIGHTLY HIGHER AMOUNTS GIVEN THE UPSLOPE
COMPONENT OF THE WINDS.

SOME OF THE HIGH RES MODELS HAVE A DECENT CLIP OF QPF INTO ESSEX
COUNTY...WHILE OTHERS HAVE NOTHING IN THE SAME AREA.  FOR NORFOLK
AND PLYMOUTH COUNTY...WE MAY SEE A BIT OF OCEAN ENHANCEMENT THAT
RAISES SNOW AMOUNTS IN THOSE AREAS.  DUE TO THE UNCERTAINTY AND THE
LOCALIZED NATURE OF THE POTENTIAL HIGHER AMOUNTS...AM OPTING NOT TO
ISSUE A WINTER WEATHER ADVISORY. INSTEAD...REISSUED THE SPECIAL
WEATHER STATEMENT FOR SNOW. ANYONE OUT AND ABOUT THIS EVENING IN
EASTERN MASSACHUSETTS WILL WANT TO USE CAUTION AS THERE MAY BE
SLIPPERY PATCHES.

&&

.SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
RAIN/SNOW SHOWERS WILL CONTINUE INTO THE MORNING HOURS...THEN TAPER
OFF AS INVERTED TROUGH PULLS AWAY FROM SOUTHERN NEW ENGLAND AND HIGH
PRESSURE STARTS TO BUILD IN.  MOST LIKELY AREAS FOR CONTINUING
SHOWERS WILL BE ALONG THE IMMEDIATE EAST COAST OF MASSACHUSETTS.

AS THE DAY GOES ON...EXPECT A SLOW DRYING TREND AS HIGH PRESSURE
BUILDS INTO THE REGION.  CLOUDS WILL STICK AROUND WITH TEMPS
GENERALLY IN THE 30S.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
BIG PICTURE... SHORTWAVE ENTERING THE PACIFIC NORTHWEST CROSSES THE
ROCKIES OVER THE WEEKEND DRIVEN BY A 160-KNOT JET.  THIS DIGS A
SUBSTANTIAL TROUGH OVER THE PLAINS MONDAY-TUESDAY WHILE PACIFIC HIGH
PRESSURE BUILDS ALONG THE PACIFIC COAST. THIS IN TURN WILL ALLOW AN
UPPER RIDGE TO BUILD ALONG THE ATLANTIC COAST AND SLOWLY SHIFT EAST
OF THE COAST.  THE JET ENERGY WORKS ITS WAY AROUND THE BASE OF THE
PLAINS TROUGH AND MOVES UP THE APPALACHANS MIDWEEK.  THIS SUPPORTS A
TRANSITION OF THE TROUGH TO NEGATIVE TILT AND SLOWER MOVEMENT...WITH
WARM MOIST AIR FOR THE ATLANTIC COAST. THE TROUGH AXIS SWINGS OVER
NEW ENGLAND CHRISTMAS DAY FOLLOWED BY A WEAK RIDGE. ANOTHER
SHORTWAVE MOVES ASHORE FROM THE PACIFIC MIDWEEK AND MOVES ACROSS THE
PLAINS BY THE END OF THE WEEK AND APPROACHES THE NORTHEAST USA
SATURDAY.

THERE IS SOME SPREAD IN DETAILS AMONG THE LONG RANGE MODELS...BUT
ALL SHOW A SIMILAR SCENARIO BOTH FOR THE MIDWEEK SYSTEM AND THE END
OF WEEK SYSTEM.  WE USED A BLEND OF GFS/ECMWF.

THE DAILIES...

SUNDAY NIGHT-MONDAY... HIGH PRESSURE REMAINS NORTH OF THE REGION
BRINGING A MOIST EAST FLOW ACROSS SOUTHERN NEW ENGLAND. UPPER
PATTERN SHOWS WEAK RIDGING AS THE PLAINS TROUGH DIGS...BUT SURFACE
FIELDS SUGGEST A LINGERING INVERTED TROUGH ALONG OR JUST OFFSHORE.
THIS SHOULD MAINTAIN CONSIDERABLE CLOUDS. COULD BE SOME DRIZZLE OR
FLURRIES NEAR THE EAST COAST BUT SUPPORTING LARGE SCALE ASCENT IS
LACKING SO PCPN SHOULD BE LIMITED.

MONDAY NIGHT-TUESDAY... LOW PRESSURE FORMS ALONG A STALLED WARM
FRONT OFF THE MID ATLANTIC COAST. AS THE LOW DEVELOPS...IT BRINGS
AN INCREASED PRESSURE GRADIENT AGAINST HIGH PRESSURE MOVING
THROUGH THE MARITIMES. THE RESULT WILL BE A STRENGTHENING LOW
LEVEL EAST- SOUTHEAST JET. THIS WILL INCREASE THE MOIST INFLOW
OVER SOUTHERN NEW ENGLAND. ALSO...AS THE JET CONVERGES ON THE
INVERTED SURFACE TROUGH IT WILL GENERATE INCREASED LOW LEVEL LIFT
AND INCREASE THE CHANCE OF PCPN. WE WILL HAVE CLOUDS AND CHANCE
POPS. TEMPS IN NORTHWEST MASS WILL BE COLD ENOUGH SO THAT THERE
MAY BE A MIX OF PCPN TYPES DURING THE MORNING.

TUESDAY NIGHT-WEDNESDAY... PLAINS UPPER TROUGH DIGS DEEPER AND MOVES
EAST...PUSHING THE UPPER RIDGE TO OUR EAST. ALSO...THE STRONG UPPER
SOUTHWEST JET MOVES UP OVER THE EASTERN USA. THIS SETUP WILL TAKE
THE PRIMARY SURFACE LOW UP THROUGH THE WESTERN GREAT LAKES.
SECONDARY LOWS FORMING ON THE SYSTEM COLD FRONT WILL MOVE OUT OF THE
GULF OF MEXICO TOWARD THE GREAT LAKES. A SOUTHWEST LOW LEVEL JET
WILL MOVE UP THE ATLANTIC COAST ON WEDNESDAY AND OVER THE TOP OF THE
EAST-SOUTHEAST FLOW AT THE SURFACE. THE RESULT WILL BE PLENTY OF LOW
LEVEL LIFT THE GENERATE PCPN.

PRECIPITABLE WATER VALUES ARE FORECAST TO EXCEED 1.5 INCHES...WHICH
IS 3 STD DEVIATIONS ABOVE NORMAL FOR DECEMBER.  THIS MEANS A LOT OF
WATER AVAILABLE AS PCPN. TEMPERATURE PROFILES WILL BE ABOVE FREEZING
SO PTYPE SHOULD BE RAIN. MODEL QPF SHOWS POTENTIAL RAINFALL OF OVER
2 INCHES. THIS WOULD SUGGEST POTENTIAL URBAN/POOR DRAINAGE FLOODING
ISSUES WEDNESDAY.

STRONG LOW LEVEL WINDS WILL ALSO BE A CONCERN ESPECIALLY WEDNESDAY
NIGHT. THE ECMWF SHOWS EAST-SOUTHEAST WINDS 30-35 KNOTS ALONG HE
EAST MASS COAST AT 1000 MB. THEN WEDNESDAY NIGHT WINDS AT 925 MB
INCREASE TO 60-75 KNOTS AND MOVE ACROSS COASTAL RI AND SOUTHEAST
MASS. STRONG DOWNPOURS MAY OVERCOME THE LOW LEVEL INVERSION AND
BRING STRONG GUSTS OF AT LEAST 30-40 KNOTS ESPECIALLY ALONG THE
SOUTH COAST. A WIND ADVISORY MAY BE NEEDED IN SOME AREAS.

MAINTAINED A LIMITED MENTION OF THUNDER...AS CONVECTIVE PARAMETERS
ARE MARGINAL...SI VALUES WILL BE JUST ABOVE ZERO AND K INDEX WILL BE
IN THE LOW 30S WEDNESDAY NIGHT.

UPPER LOW WILL SWING THE SURFACE COLD FRONT THROUGH SOUTHERN NEW
ENGLAND WEDNESDAY NIGHT. WINDS WILL THEN SHIFT TO WEST AND PCPN
SHOULD COME TO AN END AROUND THE TIME THAT SANTA ARRIVES.

CHRISTMAS DAY... WEST WINDS WILL BRING A DRYING OF THE AIRMASS
DURING THE DAY. SO THE TREND SHOULD BE TO AT LEAST PARTIAL CLEARING.
SUFFICIENT COLD ADVECTION AT ALL LEVELS THURSDAY WILL ALLOW SOME
MIXING.  WINDS IN THE SFC-850 MB LAYER WILL BE 30-40 KNOTS AND
POSSIBLY A LITTLE HIGHER...WHICH WOULD REQUIRE A WIND ADVISORY FOR
MUCH OF THE AREA.

FRIDAY-SATURDAY... WEAK HIGH PRESSURE BUILDS OVER THE AREA FRIDAY
AND BRING A SUNNY DAY. THE NEXT PACIFIC SHORTWAVE APPROACHES
SATURDAY AND SHOULD BRING INCREASING CLOUDS FROM WEST TO EAST ALONG
WITH A CHANCE OF RAIN OR SNOW SHOWERS MAINLY IN THE AFTERNOON AND AT
NIGHT.

&&

.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH SUNDAY/...

TONIGHT AND SUNDAY...MVFR CIGS/VSBYS IN RAIN/SNOW SHOWERS MOVING
WEST OFF THE OCEAN INTO SOUTHEASTERN MASS. THESE WILL SPREAD
FARTHER WEST INTO RI/CENTRAL MASS/NORTHEAST CT. LOCAL IFR
CIGS/VSBYS POSSIBLE WITH THE STRONGEST SHOWERS.

WINDS ARE ENE ALONG THE IMMEDIATE SOUTHEAST MASS COAST WITH NORTH
TO NORTHWEST WINDS ELSEWHERE. THIS WINDSHIFT MAY NUDGE FARTHER
WEST WITH THE SHOWERS EARLY TONIGHT.

MVFR CIGS MAY REACH THE CT VALLEY LATE TONIGHT BUT LOW CONFIDENCE
ABOUT ANY SIGNIFICANT REDUCTION IN VSBY THERE.

MVFR CIGS WILL LINGER MOST AREA ON SUNDAY. ANY CIGS THAT RISE
ABOVE MVFR SHOULD ONLY REACH AROUND 4000 FEET.

KBOS TERMINAL...MODERATE CONFIDENCE IN TAF. FLURRIES AND SNOW
SHOWERS THROUGH 06Z WITH POTENTIAL FOR WINDSHIFT TO 040 DURING
THIS TIME.

KBDL TERMINAL...MODERATE CONFIDENCE IN TAF.

OUTLOOK...SUNDAY NIGHT THROUGH THURSDAY...MODERATE CONFIDENCE

SUNDAY NIGHT-MONDAY...MVFR CIGS CONTINUE IN RI/EASTERN MASS IN
MARINE EAST FLOW. VFR IN THE WEST.

TUESDAY...VFR WITH SCATTERED MVFR IN ANY RAIN/SNOW SHOWERS.

WEDNESDAY...CONDITIONS LOWERING TO IFR IN RAIN/HEAVY RAIN. ISOLATED
THUNDERSTORMS POSSIBLE ESPECIALLY WEDNESDAY NIGHT. EAST-SOUTHEST
SURFACE WINDS MAY GUST TO 35 KNOTS ALONG THE EAST MASSACHUSETTS
COAST. WINDS AT 2000 FEET AGL WILL REACH 50-60 KNOTS WEDNESDAY
AFTERNOON AND EARLY NIGHT CREATING LOW LEVEL WIND SHEAR CONCERNS.

CHRISTMAS DAY...WEST WIND GUSTING 30-40 KNOTS. CONDITIONS IMPROVING
TO VFR AS THE WIND BRINGS IN COOLER DRIER AIR.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

HIGH CONFIDENCE. HIGH PRESSURE ACROSS QUEBEC WILL RESULT IN
PERSISTENT NORTHEAST WINDS ACROSS THE WATERS THROUGH THE WEEKEND.
WIND GUSTS UP TO 20 KNOTS WITH SEAS BETWEEN 2 AND 4 FEET ARE
EXPECTED FOR MOST WATERS...SO NO HEADLINES PLANNED.

THERE IS A LOW PROBABILITY THAT A BRIEF SURGE OF NORTHEAST WIND
GUSTS NEAR 25 KNOTS WITH MARGINAL 5 FOOT SEAS COULD AFFECT OUR
NORTHERN WATERS LATE TONIGHT INTO SUN MORNING...BUT NOT CONFIDENT
ENOUGH TO ISSUE ANY HEADLINES AT THIS POINT.

OUTLOOK...SUNDAY NIGHT THROUGH THURSDAY...MODERATE CONFIDENCE

SUNDAY NIGHT-MONDAY...EAST TO NORTHEAST WINDS GUSTING AROUND 15
KNOTS OR LESS.  SEAS WILL HOLD AROUND 3-4 FEET.

TUESDAY... INCREASING EAST WINDS WITH FREQUENT GUSTS 25 TO 30 KNOTS.
SEAS WILL BUILD TO 5-6 FEET ON THE EXPOSED WATERS.  A SMALL CRAFT
ADVISORY MAY BE NEEDED.

WEDNESDAY...RAIN WILL BE HEAVY AT TIMES PRODUCING POOR VISIBILITY.
INCREASING SOUTHEAST WINDS 20-25 SUSTAINED AND 40 KNOT GUSTS.  WINDS
SHOULD SHIFT TO SOUTH WEDNESDAY NIGHT AND SOUTHWEST TOWARD THURSDAY
MORNING. RAIN WILL TAPER OFF WITH THE WIND SHIFT TO SOUTHWEST. SEAS
WILL CONTINUE TO BUILD WITH 5-10 FEET HEIGHTS ON THE EXPOSED WATERS.
A GALE WARNING MAY BE NEEDED.

CHRISTMAS DAY... WEST SOUTHWEST WINDS WILL CONTINUE TO GUST 35-40
KNOTS...SO A GALE WARNING MAY CONTINUE TO BE NEEDED. SEAS OF 10-15
FEET ARE POSSIBLE ON THE EXPOSED WATERS...AND 5 FEET IS POSSIBLE ON
SOME OF THE NEARSHORE WATERS.

&&

.TIDES/COASTAL FLOODING...
HIGH ASTRONOMICAL TIDES WILL OCCUR
TUESDAY THROUGH THURSDAY. BREAKING IT DOWN...ON TUESDAY HIGH TIDE
AT BOSTON WILL BE 11.6 FT. THERE WILL BE EAST WINDS DURING THIS
HIGH TIDE ALLOWING FOR MINOR SPLASHOVER ALONG THE MASS COAST. IF
WIND GUSTS INCREASE THEN COULD POSSIBLE SEE MINOR COASTAL
FLOODING.

ON WEDNESDAY...WINDS WILL SWITCH TO A MORE SOUTHEASTERLY FLOW DURING
THE DAY AND INCREASE QUICKLY DUE TO THE APPROACHING SYSTEM.
WEDNESDAY AFTERNOON HIGH TIDE IN BOSTON IS 11.7 FT...AND AN
APPRECIABLE EAST OR SOUTHEAST WIND SHOULD PUSH LEVELS HIGHER THAN ON
TUESDAY.  THIS WOULD PROBABLY BE THE BEST CHACNE OF MINOR COASTAL
FLOODING ALONG THE EAST COAST.

THE WEDNESDAY EVENING HIGH TIDE WILL BE A LITTLE LOWER...BUT THE
WIND BECOMES SOUTH WITH 50-60 KNOTS AT 2000 FEET ABOVE THE SURFACE
AVAILABLE TO BE BROUGHT DOWN IN GUSTS. HIGH TIDE IN PROVIDENCE WILL
BE 5.2 FT. MINOR COASTAL FLOODING COULD OCCUR ALONG THE SOUTH
COASTS OF RI AND MASS...AND COULD BE CHANNELED IN NORTH-SOUTH AXIS
BAYS SUCH AS NARRAGANSETT BAY.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...WTB/RLG
NEAR TERM...WTB/RLG
SHORT TERM...RLG
LONG TERM...WTB
AVIATION...WTB/RLG
MARINE...WTB/RLG
TIDES/COASTAL FLOODING...




000
FXUS61 KBOX 202147
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
447 PM EST SAT DEC 20 2014

.SYNOPSIS...
SCATTERED SNOW/RAIN SHOWERS WILL GRADUALLY OVERSPREAD THE REGION
FROM EAST TO WEST THIS AFTERNOON THROUGH SUN. WEAK LOW PRESSURE
WILL PASS SOUTH OF NEW ENGLAND BRINGING ANOTHER PERIOD OF
PRECIPITATION MONDAY NIGHT AND TUESDAY. A MUCH STRONGER STORM
PASSING WEST OF NEW ENGLAND WILL BRING HEAVY RAINFALL...GUSTY
WINDS AND COASTAL FLOODING CONCERNS TO THE REGION WEDNESDAY
AND WEDNESDAY NIGHT. DRY BUT VERY WINDY CONDITIONS FOLLOW FOR
CHRISTMAS DAY.

&&

.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
AN INVERTED TROUGH WILL DEVELOP THIS EVENING IN RESPONSE TO A
SHORTWAVE MOVING ACROSS SOUTHERN NEW ENGLAND.  THIS WILL PROVIDE A
FOCUS FOR RAIN/SNOW SHOWERS ACROSS MUCH OF EASTERN MASSACHUSETTS
BEGINNING THIS AFTERNOON AND CONTINUING THROUGH TONIGHT.  WHILE SNOW
SHOWERS MAY REACH INTO WESTERN NEW ENGLAND TONIGHT...A COASTAL FRONT
WILL DEVELOP...AIDING IN FOCUSING SHOWERS ALONG THE EAST COAST OF
MASSACHUSETTS.

SNOW SHOWERS WILL BECOME MORE WIDESPREAD TONIGHT AS THE LOW LEVELS
MOISTEN UP A BIT MORE. LOOKS LIKE IT WILL LIKELY BE WARM ENOUGH
ACROSS THE CAPE AND SOUTHEASTERN PLYMOUTH COUNTY FOR SHOWERS TO BE
RAIN RATHER THAN SNOW.

OVERALL...EXPECTING 1-2 INCHES OF SNOW AT MOST ACROSS EASTERN
MASSACHUSETTS AND RHODE ISLAND.  THERE ARE SEVERAL POTENTIAL PLACES
WHERE LOCALIZED SLIGHTLY HIGHER AMOUNTS /POSSIBLY UP TO 2-4 INCHES/
ARE POSSIBLE.  LOOKING AT THE HIGH RES MODELS...EITHER ACROSS ESSEX
COUNTY AND CAPE ANN...EASTERN NORFOLK COUNTY INTO NORTHERN PLYMOUTH
COUNTY...OR BOTH. THEN THE HIGHER TERRAIN OF WORCESTER COUNTY AND
PROVIDENCE COUNTY MAY SEE SLIGHTLY HIGHER AMOUNTS GIVEN THE UPSLOPE
COMPONENT OF THE WINDS.

SOME OF THE HIGH RES MODELS HAVE A DECENT CLIP OF QPF INTO ESSEX
COUNTY...WHILE OTHERS HAVE NOTHING IN THE SAME AREA.  FOR NORFOLK
AND PLYMOUTH COUNTY...WE MAY SEE A BIT OF OCEAN ENHANCEMENT THAT
RAISES SNOW AMOUNTS IN THOSE AREAS.  DUE TO THE UNCERTAINTY AND THE
LOCALIZED NATURE OF THE POTENTIAL HIGHER AMOUNTS...AM OPTING NOT TO
ISSUE A WINTER WEATHER ADVISORY. INSTEAD...REISSUED THE SPECIAL
WEATHER STATEMENT FOR SNOW. ANYONE OUT AND ABOUT THIS EVENING IN
EASTERN MASSACHUSETTS WILL WANT TO USE CAUTION AS THERE MAY BE
SLIPPERY PATCHES.

&&

.SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
RAIN/SNOW SHOWERS WILL CONTINUE INTO THE MORNING HOURS...THEN TAPER
OFF AS INVERTED TROUGH PULLS AWAY FROM SOUTHERN NEW ENGLAND AND HIGH
PRESSURE STARTS TO BUILD IN.  MOST LIKELY AREAS FOR CONTINUING
SHOWERS WILL BE ALONG THE IMMEDIATE EAST COAST OF MASSACHUSETTS.

AS THE DAY GOES ON...EXPECT A SLOW DRYING TREND AS HIGH PRESSURE
BUILDS INTO THE REGION.  CLOUDS WILL STICK AROUND WITH TEMPS
GENERALLY IN THE 30S.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...

BIG PICTURE... SHORTWAVE ENTERING THE PACIFIC NORTHWEST CROSSES THE
ROCKIES OVER THE WEEKEND DRIVEN BY A 160-KNOT JET.  THIS DIGS A
SUBSTANTIAL TROUGH OVER THE PLAINS MONDAY-TUESDAY WHILE PACIFIC HIGH
PRESSURE BUILDS ALONG THE PACIFIC COAST. THIS IN TURN WILL ALLOW AN
UPPER RIDGE TO BUILD ALONG THE ATLANTIC COAST AND SLOWLY SHIFT EAST
OF THE COAST.  THE JET ENERGY WORKS ITS WAY AROUND THE BASE OF THE
PLAINS TROUGH AND MOVES UP THE APPALACHANS MIDWEEK.  THIS SUPPORTS A
TRANSITION OF THE TROUGH TO NEGATIVE TILT AND SLOWER MOVEMENT...WITH
WARM MOIST AIR FOR THE ATLANTIC COAST. THE TROUGH AXIS SWINGS OVER
NEW ENGLAND CHRISTMAS DAY FOLLOWED BY A WEAK RIDGE. ANOTHER
SHORTWAVE MOVES ASHORE FROM THE PACIFIC MIDWEEK AND MOVES ACROSS THE
PLAINS BY THE END OF THE WEEK AND APPROACHES THE NORTHEAST USA
SATURDAY.

THERE IS SOME SPREAD IN DETAILS AMONG THE LONG RANGE MODELS...BUT
ALL SHOW A SIMILAR SCENARIO BOTH FOR THE MIDWEEK SYSTEM AND THE END
OF WEEK SYSTEM.  WE USED A BLEND OF GFS/ECMWF.

THE DAILIES...

SUNDAY NIGHT-MONDAY... HIGH PRESSURE REMAINS NORTH OF THE REGION
BRINGING A MOIST EAST FLOW ACROSS SOUTHERN NEW ENGLAND. UPPER
PATTERN SHOWS WEAK RIDGING AS THE PLAINS TROUGH DIGS...BUT SURFACE
FIELDS SUGGEST A LINGERING INVERTED TROUGH ALONG OR JUST OFFSHORE.
THIS SHOULD MAINTAIN CONSIDERABLE CLOUDS. COULD BE SOME DRIZZLE OR
FLURRIES NEAR THE EAST COAST BUT SUPPORTING LARGE SCALE ASCENT IS
LACKING SO PCPN SHOULD BE LIMITED.

MONDAY NIGHT-TUESDAY... LOW PRESSURE FORMS ALONG A STALLED WARM
FRONT OFF THE MID ATLANTIC COAST. AS THE LOW DEVELOPS...IT BRINGS
AN INCREASED PRESSURE GRADIENT AGAINST HIGH PRESSURE MOVING
THROUGH THE MARITIMES. THE RESULT WILL BE A STRENGTHENING LOW
LEVEL EAST- SOUTHEAST JET. THIS WILL INCREASE THE MOIST INFLOW
OVER SOUTHERN NEW ENGLAND. ALSO...AS THE JET CONVERGES ON THE
INVERTED SURFACE TROUGH IT WILL GENERATE INCREASED LOW LEVEL LIFT
AND INCREASE THE CHANCE OF PCPN. WE WILL HAVE CLOUDS AND CHANCE
POPS. TEMPS IN NORTHWEST MASS WILL BE COLD ENOUGH SO THAT THERE
MAY BE A MIX OF PCPN TYPES DURING THE MORNING.

TUESDAY NIGHT-WEDNESDAY... PLAINS UPPER TROUGH DIGS DEEPER AND MOVES
EAST...PUSHING THE UPPER RIDGE TO OUR EAST. ALSO...THE STRONG UPPER
SOUTHWEST JET MOVES UP OVER THE EASTERN USA. THIS SETUP WILL TAKE
THE PRIMARY SURFACE LOW UP THROUGH THE WESTERN GREAT LAKES.
SECONDARY LOWS FORMING ON THE SYSTEM COLD FRONT WILL MOVE OUT OF THE
GULF OF MEXICO TOWARD THE GREAT LAKES. A SOUTHWEST LOW LEVEL JET
WILL MOVE UP THE ATLANTIC COAST ON WEDNESDAY AND OVER THE TOP OF THE
EAST-SOUTHEAST FLOW AT THE SURFACE. THE RESULT WILL BE PLENTY OF LOW
LEVEL LIFT THE GENERATE PCPN.

PRECIPITABLE WATER VALUES ARE FORECAST TO EXCEED 1.5 INCHES...WHICH
IS 3 STD DEVIATIONS ABOVE NORMAL FOR DECEMBER.  THIS MEANS A LOT OF
WATER AVAILABLE AS PCPN. TEMPERATURE PROFILES WILL BE ABOVE FREEZING
SO PTYPE SHOULD BE RAIN. MODEL QPF SHOWS POTENTIAL RAINFALL OF OVER
2 INCHES. THIS WOULD SUGGEST POTENTIAL URBAN/POOR DRAINAGE FLOODING
ISSUES WEDNESDAY.

STRONG LOW LEVEL WINDS WILL ALSO BE A CONCERN ESPECIALLY WEDNESDAY
NIGHT. THE ECMWF SHOWS EAST-SOUTHEAST WINDS 30-35 KNOTS ALONG HE
EAST MASS COAST AT 1000 MB. THEN WEDNESDAY NIGHT WINDS AT 925 MB
INCREASE TO 60-75 KNOTS AND MOVE ACROSS COASTAL RI AND SOUTHEAST
MASS. STRONG DOWNPOURS MAY OVERCOME THE LOW LEVEL INVERSION AND
BRING STRONG GUSTS OF AT LEAST 30-40 KNOTS ESPECIALLY ALONG THE
SOUTH COAST. A WIND ADVISORY MAY BE NEEDED IN SOME AREAS.

MAINTAINED A LIMITED MENTION OF THUNDER...AS CONVECTIVE PARAMETERS
ARE MARGINAL...SI VALUES WILL BE JUST ABOVE ZERO AND K INDEX WILL BE
IN THE LOW 30S WEDNESDAY NIGHT.

UPPER LOW WILL SWING THE SURFACE COLD FRONT THROUGH SOUTHERN NEW
ENGLAND WEDNESDAY NIGHT. WINDS WILL THEN SHIFT TO WEST AND PCPN
SHOULD COME TO AN END AROUND THE TIME THAT SANTA ARRIVES.

CHRISTMAS DAY... WEST WINDS WILL BRING A DRYING OF THE AIRMASS
DURING THE DAY. SO THE TREND SHOULD BE TO AT LEAST PARTIAL CLEARING.
SUFFICIENT COLD ADVECTION AT ALL LEVELS THURSDAY WILL ALLOW SOME
MIXING.  WINDS IN THE SFC-850 MB LAYER WILL BE 30-40 KNOTS AND
POSSIBLY A LITTLE HIGHER...WHICH WOULD REQUIRE A WIND ADVISORY FOR
MUCH OF THE AREA.

FRIDAY-SATURDAY... WEAK HIGH PRESSURE BUILDS OVER THE AREA FRIDAY
AND BRING A SUNNY DAY. THE NEXT PACIFIC SHORTWAVE APPROACHES
SATURDAY AND SHOULD BRING INCREASING CLOUDS FROM WEST TO EAST ALONG
WITH A CHANCE OF RAIN OR SNOW SHOWERS MAINLY IN THE AFTERNOON AND AT
NIGHT.

&&

.AVIATION /22Z SATURDAY THROUGH THURSDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH SUNDAY/...

THROUGH 00Z...MODERATE CONFIDENCE. MVFR CIGS WILL CONTINUE TO
OVERSPREAD EASTERN NEW ENGLAND AND EVENTUALLY OVERSPREAD THE INTERIOR
THIS AFTERNOON. SCATTERED SHOWERS ACROSS PORTIONS OF EASTERN
MASSACHUSETTS THIS AFTERNOON. MAINLY SNOW SHOWERS TO THE NORTH AND
WEST OF CAPE COD CANAL...RAIN SHOWERS SOUTH AND EAST. LOCALIZED
IFR CONDITIONS POSSIBLE JUST INLAND FROM THE SOUTHEAST NEW ENGLAND
COAST...WHERE SNOW IS FALLING.

TONIGHT AND SUNDAY...MODERATE CONFIDENCE.  MVFR CONDITIONS DOMINATE
IN LOWER CLOUDS AND SCATTERED SHOWERS. LOCALIZED IFR CONDITIONS
POSSIBLE WITH THE BEST CHANCE IN SNOW SHOWERS. PRECIPITATION
AFFECTS MAINLY EASTERN NEW ENGLAND BUT STILL SOME SCATTERED
ACTIVITY ACROSS WESTERN NEW ENGLAND. MAINLY SNOW SHOWERS TO THE
NORTH AND WEST OF CAPE COD CANAL...RAIN SHOWERS SOUTH AND EAST.

KBOS TERMINAL...MODERATE CONFIDENCE IN TAF. FLURRIES AND SNOW
SHOWERS MAY AFFECT THE TERMINAL BY 21Z.

KBDL TERMINAL...MODERATE CONFIDENCE IN TAF.

OUTLOOK...SUNDAY NIGHT THROUGH THURSDAY...MODERATE CONFIDENCE

SUNDAY NIGHT-MONDAY...MVFR CIGS CONTINUE IN RI/EASTERN MASS IN
MARINE EAST FLOW. VFR IN THE WEST.

TUESDAY...VFR WITH SCATTERED MVFR IN ANY RAIN/SNOW SHOWERS.

WEDNESDAY...CONDITIONS LOWERING TO IFR IN RAIN/HEAVY RAIN. ISOLATED
THUNDERSTORMS POSSIBLE ESPECIALLY WEDNESDAY NIGHT. EAST-SOUTHEST
SURFACE WINDS MAY GUST TO 35 KNOTS ALONG THE EAST MASSACHUSETTS
COAST. WINDS AT 2000 FEET AGL WILL REACH 50-60 KNOTS WEDNESDAY
AFTERNOON AND EARLY NIGHT CREATING LOW LEVEL WIND SHEAR CONCERNS.

CHRISTMAS DAY...WEST WIND GUSTING 30-40 KNOTS. CONDITIONS IMPROVING
TO VFR AS THE WIND BRINGS IN COOLER DRIER AIR.
&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

HIGH CONFIDENCE. HIGH PRESSURE ACROSS QUEBEC WILL RESULT IN
PERSISTENT NORTHEAST WINDS ACROSS THE WATERS THROUGH THE WEEKEND.
WIND GUSTS UP TO 20 KNOTS WITH SEAS BETWEEN 2 AND 4 FEET ARE
EXPECTED FOR MOST WATERS...SO NO HEADLINES PLANNED.

THERE IS A LOW PROBABILITY THAT A BRIEF SURGE OF NORTHEAST WIND
GUSTS NEAR 25 KNOTS WITH MARGINAL 5 FOOT SEAS COULD AFFECT OUR
NORTHERN WATERS LATE TONIGHT INTO SUN MORNING...BUT NOT CONFIDENT
ENOUGH TO ISSUE ANY HEADLINES AT THIS POINT.

OUTLOOK...SUNDAY NIGHT THROUGH THURSDAY...MODERATE CONFIDENCE

SUNDAY NIGHT-MONDAY...EAST TO NORTHEAST WINDS GUSTING AROUND 15
KNOTS OR LESS.  SEAS WILL HOLD AROUND 3-4 FEET.

TUESDAY... INCREASING EAST WINDS WITH FREQUENT GUSTS 25 TO 30 KNOTS.
SEAS WILL BUILD TO 5-6 FEET ON THE EXPOSED WATERS.  A SMALL CRAFT
ADVISORY MAY BE NEEDED.

WEDNESDAY...RAIN WILL BE HEAVY AT TIMES PRODUCING POOR VISIBILITY.
INCREASING SOUTHEAST WINDS 20-25 SUSTAINED AND 40 KNOT GUSTS.  WINDS
SHOULD SHIFT TO SOUTH WEDNESDAY NIGHT AND SOUTHWEST TOWARD THURSDAY
MORNING. RAIN WILL TAPER OFF WITH THE WIND SHIFT TO SOUTHWEST. SEAS
WILL CONTINUE TO BUILD WITH 5-10 FEET HEIGHTS ON THE EXPOSED WATERS.
A GALE WARNING MAY BE NEEDED.

CHRISTMAS DAY... WEST SOUTHWEST WINDS WILL CONTINUE TO GUST 35-40
KNOTS...SO A GALE WARNING MAY CONTINUE TO BE NEEDED. SEAS OF 10-15
FEET ARE POSSIBLE ON THE EXPOSED WATERS...AND 5 FEET IS POSSIBLE ON
SOME OF THE NEARSHORE WATERS.

&&

.TIDES/COASTAL FLOODING... HIGH ASTRONOMICAL TIDES WILL OCCUR
TUESDAY THROUGH THURSDAY. BREAKING IT DOWN...ON TUESDAY HIGH TIDE
AT BOSTON WILL BE 11.6 FT. THERE WILL BE EAST WINDS DURING THIS
HIGH TIDE ALLOWING FOR MINOR SPLASHOVER ALONG THE MASS COAST. IF
WIND GUSTS INCREASE THEN COULD POSSIBLE SEE MINOR COASTAL
FLOODING.

ON WEDNESDAY...WINDS WILL SWITCH TO A MORE SOUTHEASTERLY FLOW DURING
THE DAY AND INCREASE QUICKLY DUE TO THE APPROACHING SYSTEM.
WEDNESDAY AFTERNOON HIGH TIDE IN BOSTON IS 11.7 FT...AND AN
APPRECIABLE EAST OR SOUTHEAST WIND SHOULD PUSH LEVELS HIGHER THAN ON
TUESDAY.  THIS WOULD PROBABLY BE THE BEST CHACNE OF MINOR COASTAL
FLOODING ALONG THE EAST COAST.

THE WEDNESDAY EVENING HIGH TIDE WILL BE A LITTLE LOWER...BUT THE
WIND BECOMES SOUTH WITH 50-60 KNOTS AT 2000 FEET ABOVE THE SURFACE
AVAILABLE TO BE BROUGHT DOWN IN GUSTS. HIGH TIDE IN PROVIDENCE WILL
BE 5.2 FT. MINOR COASTAL FLOODING COULD OCCUR ALONG THE SOUTH
COASTS OF RI AND MASS...AND COULD BE CHANNELED IN NORTH-SOUTH AXIS
BAYS SUCH AS NARRAGANSETT BAY.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...WTB/RLG
NEAR TERM...RLG
SHORT TERM...RLG
LONG TERM...WTB
AVIATION...WTB/RLG
MARINE...WTB/RLG
TIDES/COASTAL FLOODING...




000
FXUS61 KBOX 202147
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
447 PM EST SAT DEC 20 2014

.SYNOPSIS...
SCATTERED SNOW/RAIN SHOWERS WILL GRADUALLY OVERSPREAD THE REGION
FROM EAST TO WEST THIS AFTERNOON THROUGH SUN. WEAK LOW PRESSURE
WILL PASS SOUTH OF NEW ENGLAND BRINGING ANOTHER PERIOD OF
PRECIPITATION MONDAY NIGHT AND TUESDAY. A MUCH STRONGER STORM
PASSING WEST OF NEW ENGLAND WILL BRING HEAVY RAINFALL...GUSTY
WINDS AND COASTAL FLOODING CONCERNS TO THE REGION WEDNESDAY
AND WEDNESDAY NIGHT. DRY BUT VERY WINDY CONDITIONS FOLLOW FOR
CHRISTMAS DAY.

&&

.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
AN INVERTED TROUGH WILL DEVELOP THIS EVENING IN RESPONSE TO A
SHORTWAVE MOVING ACROSS SOUTHERN NEW ENGLAND.  THIS WILL PROVIDE A
FOCUS FOR RAIN/SNOW SHOWERS ACROSS MUCH OF EASTERN MASSACHUSETTS
BEGINNING THIS AFTERNOON AND CONTINUING THROUGH TONIGHT.  WHILE SNOW
SHOWERS MAY REACH INTO WESTERN NEW ENGLAND TONIGHT...A COASTAL FRONT
WILL DEVELOP...AIDING IN FOCUSING SHOWERS ALONG THE EAST COAST OF
MASSACHUSETTS.

SNOW SHOWERS WILL BECOME MORE WIDESPREAD TONIGHT AS THE LOW LEVELS
MOISTEN UP A BIT MORE. LOOKS LIKE IT WILL LIKELY BE WARM ENOUGH
ACROSS THE CAPE AND SOUTHEASTERN PLYMOUTH COUNTY FOR SHOWERS TO BE
RAIN RATHER THAN SNOW.

OVERALL...EXPECTING 1-2 INCHES OF SNOW AT MOST ACROSS EASTERN
MASSACHUSETTS AND RHODE ISLAND.  THERE ARE SEVERAL POTENTIAL PLACES
WHERE LOCALIZED SLIGHTLY HIGHER AMOUNTS /POSSIBLY UP TO 2-4 INCHES/
ARE POSSIBLE.  LOOKING AT THE HIGH RES MODELS...EITHER ACROSS ESSEX
COUNTY AND CAPE ANN...EASTERN NORFOLK COUNTY INTO NORTHERN PLYMOUTH
COUNTY...OR BOTH. THEN THE HIGHER TERRAIN OF WORCESTER COUNTY AND
PROVIDENCE COUNTY MAY SEE SLIGHTLY HIGHER AMOUNTS GIVEN THE UPSLOPE
COMPONENT OF THE WINDS.

SOME OF THE HIGH RES MODELS HAVE A DECENT CLIP OF QPF INTO ESSEX
COUNTY...WHILE OTHERS HAVE NOTHING IN THE SAME AREA.  FOR NORFOLK
AND PLYMOUTH COUNTY...WE MAY SEE A BIT OF OCEAN ENHANCEMENT THAT
RAISES SNOW AMOUNTS IN THOSE AREAS.  DUE TO THE UNCERTAINTY AND THE
LOCALIZED NATURE OF THE POTENTIAL HIGHER AMOUNTS...AM OPTING NOT TO
ISSUE A WINTER WEATHER ADVISORY. INSTEAD...REISSUED THE SPECIAL
WEATHER STATEMENT FOR SNOW. ANYONE OUT AND ABOUT THIS EVENING IN
EASTERN MASSACHUSETTS WILL WANT TO USE CAUTION AS THERE MAY BE
SLIPPERY PATCHES.

&&

.SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
RAIN/SNOW SHOWERS WILL CONTINUE INTO THE MORNING HOURS...THEN TAPER
OFF AS INVERTED TROUGH PULLS AWAY FROM SOUTHERN NEW ENGLAND AND HIGH
PRESSURE STARTS TO BUILD IN.  MOST LIKELY AREAS FOR CONTINUING
SHOWERS WILL BE ALONG THE IMMEDIATE EAST COAST OF MASSACHUSETTS.

AS THE DAY GOES ON...EXPECT A SLOW DRYING TREND AS HIGH PRESSURE
BUILDS INTO THE REGION.  CLOUDS WILL STICK AROUND WITH TEMPS
GENERALLY IN THE 30S.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...

BIG PICTURE... SHORTWAVE ENTERING THE PACIFIC NORTHWEST CROSSES THE
ROCKIES OVER THE WEEKEND DRIVEN BY A 160-KNOT JET.  THIS DIGS A
SUBSTANTIAL TROUGH OVER THE PLAINS MONDAY-TUESDAY WHILE PACIFIC HIGH
PRESSURE BUILDS ALONG THE PACIFIC COAST. THIS IN TURN WILL ALLOW AN
UPPER RIDGE TO BUILD ALONG THE ATLANTIC COAST AND SLOWLY SHIFT EAST
OF THE COAST.  THE JET ENERGY WORKS ITS WAY AROUND THE BASE OF THE
PLAINS TROUGH AND MOVES UP THE APPALACHANS MIDWEEK.  THIS SUPPORTS A
TRANSITION OF THE TROUGH TO NEGATIVE TILT AND SLOWER MOVEMENT...WITH
WARM MOIST AIR FOR THE ATLANTIC COAST. THE TROUGH AXIS SWINGS OVER
NEW ENGLAND CHRISTMAS DAY FOLLOWED BY A WEAK RIDGE. ANOTHER
SHORTWAVE MOVES ASHORE FROM THE PACIFIC MIDWEEK AND MOVES ACROSS THE
PLAINS BY THE END OF THE WEEK AND APPROACHES THE NORTHEAST USA
SATURDAY.

THERE IS SOME SPREAD IN DETAILS AMONG THE LONG RANGE MODELS...BUT
ALL SHOW A SIMILAR SCENARIO BOTH FOR THE MIDWEEK SYSTEM AND THE END
OF WEEK SYSTEM.  WE USED A BLEND OF GFS/ECMWF.

THE DAILIES...

SUNDAY NIGHT-MONDAY... HIGH PRESSURE REMAINS NORTH OF THE REGION
BRINGING A MOIST EAST FLOW ACROSS SOUTHERN NEW ENGLAND. UPPER
PATTERN SHOWS WEAK RIDGING AS THE PLAINS TROUGH DIGS...BUT SURFACE
FIELDS SUGGEST A LINGERING INVERTED TROUGH ALONG OR JUST OFFSHORE.
THIS SHOULD MAINTAIN CONSIDERABLE CLOUDS. COULD BE SOME DRIZZLE OR
FLURRIES NEAR THE EAST COAST BUT SUPPORTING LARGE SCALE ASCENT IS
LACKING SO PCPN SHOULD BE LIMITED.

MONDAY NIGHT-TUESDAY... LOW PRESSURE FORMS ALONG A STALLED WARM
FRONT OFF THE MID ATLANTIC COAST. AS THE LOW DEVELOPS...IT BRINGS
AN INCREASED PRESSURE GRADIENT AGAINST HIGH PRESSURE MOVING
THROUGH THE MARITIMES. THE RESULT WILL BE A STRENGTHENING LOW
LEVEL EAST- SOUTHEAST JET. THIS WILL INCREASE THE MOIST INFLOW
OVER SOUTHERN NEW ENGLAND. ALSO...AS THE JET CONVERGES ON THE
INVERTED SURFACE TROUGH IT WILL GENERATE INCREASED LOW LEVEL LIFT
AND INCREASE THE CHANCE OF PCPN. WE WILL HAVE CLOUDS AND CHANCE
POPS. TEMPS IN NORTHWEST MASS WILL BE COLD ENOUGH SO THAT THERE
MAY BE A MIX OF PCPN TYPES DURING THE MORNING.

TUESDAY NIGHT-WEDNESDAY... PLAINS UPPER TROUGH DIGS DEEPER AND MOVES
EAST...PUSHING THE UPPER RIDGE TO OUR EAST. ALSO...THE STRONG UPPER
SOUTHWEST JET MOVES UP OVER THE EASTERN USA. THIS SETUP WILL TAKE
THE PRIMARY SURFACE LOW UP THROUGH THE WESTERN GREAT LAKES.
SECONDARY LOWS FORMING ON THE SYSTEM COLD FRONT WILL MOVE OUT OF THE
GULF OF MEXICO TOWARD THE GREAT LAKES. A SOUTHWEST LOW LEVEL JET
WILL MOVE UP THE ATLANTIC COAST ON WEDNESDAY AND OVER THE TOP OF THE
EAST-SOUTHEAST FLOW AT THE SURFACE. THE RESULT WILL BE PLENTY OF LOW
LEVEL LIFT THE GENERATE PCPN.

PRECIPITABLE WATER VALUES ARE FORECAST TO EXCEED 1.5 INCHES...WHICH
IS 3 STD DEVIATIONS ABOVE NORMAL FOR DECEMBER.  THIS MEANS A LOT OF
WATER AVAILABLE AS PCPN. TEMPERATURE PROFILES WILL BE ABOVE FREEZING
SO PTYPE SHOULD BE RAIN. MODEL QPF SHOWS POTENTIAL RAINFALL OF OVER
2 INCHES. THIS WOULD SUGGEST POTENTIAL URBAN/POOR DRAINAGE FLOODING
ISSUES WEDNESDAY.

STRONG LOW LEVEL WINDS WILL ALSO BE A CONCERN ESPECIALLY WEDNESDAY
NIGHT. THE ECMWF SHOWS EAST-SOUTHEAST WINDS 30-35 KNOTS ALONG HE
EAST MASS COAST AT 1000 MB. THEN WEDNESDAY NIGHT WINDS AT 925 MB
INCREASE TO 60-75 KNOTS AND MOVE ACROSS COASTAL RI AND SOUTHEAST
MASS. STRONG DOWNPOURS MAY OVERCOME THE LOW LEVEL INVERSION AND
BRING STRONG GUSTS OF AT LEAST 30-40 KNOTS ESPECIALLY ALONG THE
SOUTH COAST. A WIND ADVISORY MAY BE NEEDED IN SOME AREAS.

MAINTAINED A LIMITED MENTION OF THUNDER...AS CONVECTIVE PARAMETERS
ARE MARGINAL...SI VALUES WILL BE JUST ABOVE ZERO AND K INDEX WILL BE
IN THE LOW 30S WEDNESDAY NIGHT.

UPPER LOW WILL SWING THE SURFACE COLD FRONT THROUGH SOUTHERN NEW
ENGLAND WEDNESDAY NIGHT. WINDS WILL THEN SHIFT TO WEST AND PCPN
SHOULD COME TO AN END AROUND THE TIME THAT SANTA ARRIVES.

CHRISTMAS DAY... WEST WINDS WILL BRING A DRYING OF THE AIRMASS
DURING THE DAY. SO THE TREND SHOULD BE TO AT LEAST PARTIAL CLEARING.
SUFFICIENT COLD ADVECTION AT ALL LEVELS THURSDAY WILL ALLOW SOME
MIXING.  WINDS IN THE SFC-850 MB LAYER WILL BE 30-40 KNOTS AND
POSSIBLY A LITTLE HIGHER...WHICH WOULD REQUIRE A WIND ADVISORY FOR
MUCH OF THE AREA.

FRIDAY-SATURDAY... WEAK HIGH PRESSURE BUILDS OVER THE AREA FRIDAY
AND BRING A SUNNY DAY. THE NEXT PACIFIC SHORTWAVE APPROACHES
SATURDAY AND SHOULD BRING INCREASING CLOUDS FROM WEST TO EAST ALONG
WITH A CHANCE OF RAIN OR SNOW SHOWERS MAINLY IN THE AFTERNOON AND AT
NIGHT.

&&

.AVIATION /22Z SATURDAY THROUGH THURSDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH SUNDAY/...

THROUGH 00Z...MODERATE CONFIDENCE. MVFR CIGS WILL CONTINUE TO
OVERSPREAD EASTERN NEW ENGLAND AND EVENTUALLY OVERSPREAD THE INTERIOR
THIS AFTERNOON. SCATTERED SHOWERS ACROSS PORTIONS OF EASTERN
MASSACHUSETTS THIS AFTERNOON. MAINLY SNOW SHOWERS TO THE NORTH AND
WEST OF CAPE COD CANAL...RAIN SHOWERS SOUTH AND EAST. LOCALIZED
IFR CONDITIONS POSSIBLE JUST INLAND FROM THE SOUTHEAST NEW ENGLAND
COAST...WHERE SNOW IS FALLING.

TONIGHT AND SUNDAY...MODERATE CONFIDENCE.  MVFR CONDITIONS DOMINATE
IN LOWER CLOUDS AND SCATTERED SHOWERS. LOCALIZED IFR CONDITIONS
POSSIBLE WITH THE BEST CHANCE IN SNOW SHOWERS. PRECIPITATION
AFFECTS MAINLY EASTERN NEW ENGLAND BUT STILL SOME SCATTERED
ACTIVITY ACROSS WESTERN NEW ENGLAND. MAINLY SNOW SHOWERS TO THE
NORTH AND WEST OF CAPE COD CANAL...RAIN SHOWERS SOUTH AND EAST.

KBOS TERMINAL...MODERATE CONFIDENCE IN TAF. FLURRIES AND SNOW
SHOWERS MAY AFFECT THE TERMINAL BY 21Z.

KBDL TERMINAL...MODERATE CONFIDENCE IN TAF.

OUTLOOK...SUNDAY NIGHT THROUGH THURSDAY...MODERATE CONFIDENCE

SUNDAY NIGHT-MONDAY...MVFR CIGS CONTINUE IN RI/EASTERN MASS IN
MARINE EAST FLOW. VFR IN THE WEST.

TUESDAY...VFR WITH SCATTERED MVFR IN ANY RAIN/SNOW SHOWERS.

WEDNESDAY...CONDITIONS LOWERING TO IFR IN RAIN/HEAVY RAIN. ISOLATED
THUNDERSTORMS POSSIBLE ESPECIALLY WEDNESDAY NIGHT. EAST-SOUTHEST
SURFACE WINDS MAY GUST TO 35 KNOTS ALONG THE EAST MASSACHUSETTS
COAST. WINDS AT 2000 FEET AGL WILL REACH 50-60 KNOTS WEDNESDAY
AFTERNOON AND EARLY NIGHT CREATING LOW LEVEL WIND SHEAR CONCERNS.

CHRISTMAS DAY...WEST WIND GUSTING 30-40 KNOTS. CONDITIONS IMPROVING
TO VFR AS THE WIND BRINGS IN COOLER DRIER AIR.
&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

HIGH CONFIDENCE. HIGH PRESSURE ACROSS QUEBEC WILL RESULT IN
PERSISTENT NORTHEAST WINDS ACROSS THE WATERS THROUGH THE WEEKEND.
WIND GUSTS UP TO 20 KNOTS WITH SEAS BETWEEN 2 AND 4 FEET ARE
EXPECTED FOR MOST WATERS...SO NO HEADLINES PLANNED.

THERE IS A LOW PROBABILITY THAT A BRIEF SURGE OF NORTHEAST WIND
GUSTS NEAR 25 KNOTS WITH MARGINAL 5 FOOT SEAS COULD AFFECT OUR
NORTHERN WATERS LATE TONIGHT INTO SUN MORNING...BUT NOT CONFIDENT
ENOUGH TO ISSUE ANY HEADLINES AT THIS POINT.

OUTLOOK...SUNDAY NIGHT THROUGH THURSDAY...MODERATE CONFIDENCE

SUNDAY NIGHT-MONDAY...EAST TO NORTHEAST WINDS GUSTING AROUND 15
KNOTS OR LESS.  SEAS WILL HOLD AROUND 3-4 FEET.

TUESDAY... INCREASING EAST WINDS WITH FREQUENT GUSTS 25 TO 30 KNOTS.
SEAS WILL BUILD TO 5-6 FEET ON THE EXPOSED WATERS.  A SMALL CRAFT
ADVISORY MAY BE NEEDED.

WEDNESDAY...RAIN WILL BE HEAVY AT TIMES PRODUCING POOR VISIBILITY.
INCREASING SOUTHEAST WINDS 20-25 SUSTAINED AND 40 KNOT GUSTS.  WINDS
SHOULD SHIFT TO SOUTH WEDNESDAY NIGHT AND SOUTHWEST TOWARD THURSDAY
MORNING. RAIN WILL TAPER OFF WITH THE WIND SHIFT TO SOUTHWEST. SEAS
WILL CONTINUE TO BUILD WITH 5-10 FEET HEIGHTS ON THE EXPOSED WATERS.
A GALE WARNING MAY BE NEEDED.

CHRISTMAS DAY... WEST SOUTHWEST WINDS WILL CONTINUE TO GUST 35-40
KNOTS...SO A GALE WARNING MAY CONTINUE TO BE NEEDED. SEAS OF 10-15
FEET ARE POSSIBLE ON THE EXPOSED WATERS...AND 5 FEET IS POSSIBLE ON
SOME OF THE NEARSHORE WATERS.

&&

.TIDES/COASTAL FLOODING... HIGH ASTRONOMICAL TIDES WILL OCCUR
TUESDAY THROUGH THURSDAY. BREAKING IT DOWN...ON TUESDAY HIGH TIDE
AT BOSTON WILL BE 11.6 FT. THERE WILL BE EAST WINDS DURING THIS
HIGH TIDE ALLOWING FOR MINOR SPLASHOVER ALONG THE MASS COAST. IF
WIND GUSTS INCREASE THEN COULD POSSIBLE SEE MINOR COASTAL
FLOODING.

ON WEDNESDAY...WINDS WILL SWITCH TO A MORE SOUTHEASTERLY FLOW DURING
THE DAY AND INCREASE QUICKLY DUE TO THE APPROACHING SYSTEM.
WEDNESDAY AFTERNOON HIGH TIDE IN BOSTON IS 11.7 FT...AND AN
APPRECIABLE EAST OR SOUTHEAST WIND SHOULD PUSH LEVELS HIGHER THAN ON
TUESDAY.  THIS WOULD PROBABLY BE THE BEST CHACNE OF MINOR COASTAL
FLOODING ALONG THE EAST COAST.

THE WEDNESDAY EVENING HIGH TIDE WILL BE A LITTLE LOWER...BUT THE
WIND BECOMES SOUTH WITH 50-60 KNOTS AT 2000 FEET ABOVE THE SURFACE
AVAILABLE TO BE BROUGHT DOWN IN GUSTS. HIGH TIDE IN PROVIDENCE WILL
BE 5.2 FT. MINOR COASTAL FLOODING COULD OCCUR ALONG THE SOUTH
COASTS OF RI AND MASS...AND COULD BE CHANNELED IN NORTH-SOUTH AXIS
BAYS SUCH AS NARRAGANSETT BAY.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...WTB/RLG
NEAR TERM...RLG
SHORT TERM...RLG
LONG TERM...WTB
AVIATION...WTB/RLG
MARINE...WTB/RLG
TIDES/COASTAL FLOODING...




000
FXUS61 KBOX 202147
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
447 PM EST SAT DEC 20 2014

.SYNOPSIS...
SCATTERED SNOW/RAIN SHOWERS WILL GRADUALLY OVERSPREAD THE REGION
FROM EAST TO WEST THIS AFTERNOON THROUGH SUN. WEAK LOW PRESSURE
WILL PASS SOUTH OF NEW ENGLAND BRINGING ANOTHER PERIOD OF
PRECIPITATION MONDAY NIGHT AND TUESDAY. A MUCH STRONGER STORM
PASSING WEST OF NEW ENGLAND WILL BRING HEAVY RAINFALL...GUSTY
WINDS AND COASTAL FLOODING CONCERNS TO THE REGION WEDNESDAY
AND WEDNESDAY NIGHT. DRY BUT VERY WINDY CONDITIONS FOLLOW FOR
CHRISTMAS DAY.

&&

.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
AN INVERTED TROUGH WILL DEVELOP THIS EVENING IN RESPONSE TO A
SHORTWAVE MOVING ACROSS SOUTHERN NEW ENGLAND.  THIS WILL PROVIDE A
FOCUS FOR RAIN/SNOW SHOWERS ACROSS MUCH OF EASTERN MASSACHUSETTS
BEGINNING THIS AFTERNOON AND CONTINUING THROUGH TONIGHT.  WHILE SNOW
SHOWERS MAY REACH INTO WESTERN NEW ENGLAND TONIGHT...A COASTAL FRONT
WILL DEVELOP...AIDING IN FOCUSING SHOWERS ALONG THE EAST COAST OF
MASSACHUSETTS.

SNOW SHOWERS WILL BECOME MORE WIDESPREAD TONIGHT AS THE LOW LEVELS
MOISTEN UP A BIT MORE. LOOKS LIKE IT WILL LIKELY BE WARM ENOUGH
ACROSS THE CAPE AND SOUTHEASTERN PLYMOUTH COUNTY FOR SHOWERS TO BE
RAIN RATHER THAN SNOW.

OVERALL...EXPECTING 1-2 INCHES OF SNOW AT MOST ACROSS EASTERN
MASSACHUSETTS AND RHODE ISLAND.  THERE ARE SEVERAL POTENTIAL PLACES
WHERE LOCALIZED SLIGHTLY HIGHER AMOUNTS /POSSIBLY UP TO 2-4 INCHES/
ARE POSSIBLE.  LOOKING AT THE HIGH RES MODELS...EITHER ACROSS ESSEX
COUNTY AND CAPE ANN...EASTERN NORFOLK COUNTY INTO NORTHERN PLYMOUTH
COUNTY...OR BOTH. THEN THE HIGHER TERRAIN OF WORCESTER COUNTY AND
PROVIDENCE COUNTY MAY SEE SLIGHTLY HIGHER AMOUNTS GIVEN THE UPSLOPE
COMPONENT OF THE WINDS.

SOME OF THE HIGH RES MODELS HAVE A DECENT CLIP OF QPF INTO ESSEX
COUNTY...WHILE OTHERS HAVE NOTHING IN THE SAME AREA.  FOR NORFOLK
AND PLYMOUTH COUNTY...WE MAY SEE A BIT OF OCEAN ENHANCEMENT THAT
RAISES SNOW AMOUNTS IN THOSE AREAS.  DUE TO THE UNCERTAINTY AND THE
LOCALIZED NATURE OF THE POTENTIAL HIGHER AMOUNTS...AM OPTING NOT TO
ISSUE A WINTER WEATHER ADVISORY. INSTEAD...REISSUED THE SPECIAL
WEATHER STATEMENT FOR SNOW. ANYONE OUT AND ABOUT THIS EVENING IN
EASTERN MASSACHUSETTS WILL WANT TO USE CAUTION AS THERE MAY BE
SLIPPERY PATCHES.

&&

.SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
RAIN/SNOW SHOWERS WILL CONTINUE INTO THE MORNING HOURS...THEN TAPER
OFF AS INVERTED TROUGH PULLS AWAY FROM SOUTHERN NEW ENGLAND AND HIGH
PRESSURE STARTS TO BUILD IN.  MOST LIKELY AREAS FOR CONTINUING
SHOWERS WILL BE ALONG THE IMMEDIATE EAST COAST OF MASSACHUSETTS.

AS THE DAY GOES ON...EXPECT A SLOW DRYING TREND AS HIGH PRESSURE
BUILDS INTO THE REGION.  CLOUDS WILL STICK AROUND WITH TEMPS
GENERALLY IN THE 30S.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...

BIG PICTURE... SHORTWAVE ENTERING THE PACIFIC NORTHWEST CROSSES THE
ROCKIES OVER THE WEEKEND DRIVEN BY A 160-KNOT JET.  THIS DIGS A
SUBSTANTIAL TROUGH OVER THE PLAINS MONDAY-TUESDAY WHILE PACIFIC HIGH
PRESSURE BUILDS ALONG THE PACIFIC COAST. THIS IN TURN WILL ALLOW AN
UPPER RIDGE TO BUILD ALONG THE ATLANTIC COAST AND SLOWLY SHIFT EAST
OF THE COAST.  THE JET ENERGY WORKS ITS WAY AROUND THE BASE OF THE
PLAINS TROUGH AND MOVES UP THE APPALACHANS MIDWEEK.  THIS SUPPORTS A
TRANSITION OF THE TROUGH TO NEGATIVE TILT AND SLOWER MOVEMENT...WITH
WARM MOIST AIR FOR THE ATLANTIC COAST. THE TROUGH AXIS SWINGS OVER
NEW ENGLAND CHRISTMAS DAY FOLLOWED BY A WEAK RIDGE. ANOTHER
SHORTWAVE MOVES ASHORE FROM THE PACIFIC MIDWEEK AND MOVES ACROSS THE
PLAINS BY THE END OF THE WEEK AND APPROACHES THE NORTHEAST USA
SATURDAY.

THERE IS SOME SPREAD IN DETAILS AMONG THE LONG RANGE MODELS...BUT
ALL SHOW A SIMILAR SCENARIO BOTH FOR THE MIDWEEK SYSTEM AND THE END
OF WEEK SYSTEM.  WE USED A BLEND OF GFS/ECMWF.

THE DAILIES...

SUNDAY NIGHT-MONDAY... HIGH PRESSURE REMAINS NORTH OF THE REGION
BRINGING A MOIST EAST FLOW ACROSS SOUTHERN NEW ENGLAND. UPPER
PATTERN SHOWS WEAK RIDGING AS THE PLAINS TROUGH DIGS...BUT SURFACE
FIELDS SUGGEST A LINGERING INVERTED TROUGH ALONG OR JUST OFFSHORE.
THIS SHOULD MAINTAIN CONSIDERABLE CLOUDS. COULD BE SOME DRIZZLE OR
FLURRIES NEAR THE EAST COAST BUT SUPPORTING LARGE SCALE ASCENT IS
LACKING SO PCPN SHOULD BE LIMITED.

MONDAY NIGHT-TUESDAY... LOW PRESSURE FORMS ALONG A STALLED WARM
FRONT OFF THE MID ATLANTIC COAST. AS THE LOW DEVELOPS...IT BRINGS
AN INCREASED PRESSURE GRADIENT AGAINST HIGH PRESSURE MOVING
THROUGH THE MARITIMES. THE RESULT WILL BE A STRENGTHENING LOW
LEVEL EAST- SOUTHEAST JET. THIS WILL INCREASE THE MOIST INFLOW
OVER SOUTHERN NEW ENGLAND. ALSO...AS THE JET CONVERGES ON THE
INVERTED SURFACE TROUGH IT WILL GENERATE INCREASED LOW LEVEL LIFT
AND INCREASE THE CHANCE OF PCPN. WE WILL HAVE CLOUDS AND CHANCE
POPS. TEMPS IN NORTHWEST MASS WILL BE COLD ENOUGH SO THAT THERE
MAY BE A MIX OF PCPN TYPES DURING THE MORNING.

TUESDAY NIGHT-WEDNESDAY... PLAINS UPPER TROUGH DIGS DEEPER AND MOVES
EAST...PUSHING THE UPPER RIDGE TO OUR EAST. ALSO...THE STRONG UPPER
SOUTHWEST JET MOVES UP OVER THE EASTERN USA. THIS SETUP WILL TAKE
THE PRIMARY SURFACE LOW UP THROUGH THE WESTERN GREAT LAKES.
SECONDARY LOWS FORMING ON THE SYSTEM COLD FRONT WILL MOVE OUT OF THE
GULF OF MEXICO TOWARD THE GREAT LAKES. A SOUTHWEST LOW LEVEL JET
WILL MOVE UP THE ATLANTIC COAST ON WEDNESDAY AND OVER THE TOP OF THE
EAST-SOUTHEAST FLOW AT THE SURFACE. THE RESULT WILL BE PLENTY OF LOW
LEVEL LIFT THE GENERATE PCPN.

PRECIPITABLE WATER VALUES ARE FORECAST TO EXCEED 1.5 INCHES...WHICH
IS 3 STD DEVIATIONS ABOVE NORMAL FOR DECEMBER.  THIS MEANS A LOT OF
WATER AVAILABLE AS PCPN. TEMPERATURE PROFILES WILL BE ABOVE FREEZING
SO PTYPE SHOULD BE RAIN. MODEL QPF SHOWS POTENTIAL RAINFALL OF OVER
2 INCHES. THIS WOULD SUGGEST POTENTIAL URBAN/POOR DRAINAGE FLOODING
ISSUES WEDNESDAY.

STRONG LOW LEVEL WINDS WILL ALSO BE A CONCERN ESPECIALLY WEDNESDAY
NIGHT. THE ECMWF SHOWS EAST-SOUTHEAST WINDS 30-35 KNOTS ALONG HE
EAST MASS COAST AT 1000 MB. THEN WEDNESDAY NIGHT WINDS AT 925 MB
INCREASE TO 60-75 KNOTS AND MOVE ACROSS COASTAL RI AND SOUTHEAST
MASS. STRONG DOWNPOURS MAY OVERCOME THE LOW LEVEL INVERSION AND
BRING STRONG GUSTS OF AT LEAST 30-40 KNOTS ESPECIALLY ALONG THE
SOUTH COAST. A WIND ADVISORY MAY BE NEEDED IN SOME AREAS.

MAINTAINED A LIMITED MENTION OF THUNDER...AS CONVECTIVE PARAMETERS
ARE MARGINAL...SI VALUES WILL BE JUST ABOVE ZERO AND K INDEX WILL BE
IN THE LOW 30S WEDNESDAY NIGHT.

UPPER LOW WILL SWING THE SURFACE COLD FRONT THROUGH SOUTHERN NEW
ENGLAND WEDNESDAY NIGHT. WINDS WILL THEN SHIFT TO WEST AND PCPN
SHOULD COME TO AN END AROUND THE TIME THAT SANTA ARRIVES.

CHRISTMAS DAY... WEST WINDS WILL BRING A DRYING OF THE AIRMASS
DURING THE DAY. SO THE TREND SHOULD BE TO AT LEAST PARTIAL CLEARING.
SUFFICIENT COLD ADVECTION AT ALL LEVELS THURSDAY WILL ALLOW SOME
MIXING.  WINDS IN THE SFC-850 MB LAYER WILL BE 30-40 KNOTS AND
POSSIBLY A LITTLE HIGHER...WHICH WOULD REQUIRE A WIND ADVISORY FOR
MUCH OF THE AREA.

FRIDAY-SATURDAY... WEAK HIGH PRESSURE BUILDS OVER THE AREA FRIDAY
AND BRING A SUNNY DAY. THE NEXT PACIFIC SHORTWAVE APPROACHES
SATURDAY AND SHOULD BRING INCREASING CLOUDS FROM WEST TO EAST ALONG
WITH A CHANCE OF RAIN OR SNOW SHOWERS MAINLY IN THE AFTERNOON AND AT
NIGHT.

&&

.AVIATION /22Z SATURDAY THROUGH THURSDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH SUNDAY/...

THROUGH 00Z...MODERATE CONFIDENCE. MVFR CIGS WILL CONTINUE TO
OVERSPREAD EASTERN NEW ENGLAND AND EVENTUALLY OVERSPREAD THE INTERIOR
THIS AFTERNOON. SCATTERED SHOWERS ACROSS PORTIONS OF EASTERN
MASSACHUSETTS THIS AFTERNOON. MAINLY SNOW SHOWERS TO THE NORTH AND
WEST OF CAPE COD CANAL...RAIN SHOWERS SOUTH AND EAST. LOCALIZED
IFR CONDITIONS POSSIBLE JUST INLAND FROM THE SOUTHEAST NEW ENGLAND
COAST...WHERE SNOW IS FALLING.

TONIGHT AND SUNDAY...MODERATE CONFIDENCE.  MVFR CONDITIONS DOMINATE
IN LOWER CLOUDS AND SCATTERED SHOWERS. LOCALIZED IFR CONDITIONS
POSSIBLE WITH THE BEST CHANCE IN SNOW SHOWERS. PRECIPITATION
AFFECTS MAINLY EASTERN NEW ENGLAND BUT STILL SOME SCATTERED
ACTIVITY ACROSS WESTERN NEW ENGLAND. MAINLY SNOW SHOWERS TO THE
NORTH AND WEST OF CAPE COD CANAL...RAIN SHOWERS SOUTH AND EAST.

KBOS TERMINAL...MODERATE CONFIDENCE IN TAF. FLURRIES AND SNOW
SHOWERS MAY AFFECT THE TERMINAL BY 21Z.

KBDL TERMINAL...MODERATE CONFIDENCE IN TAF.

OUTLOOK...SUNDAY NIGHT THROUGH THURSDAY...MODERATE CONFIDENCE

SUNDAY NIGHT-MONDAY...MVFR CIGS CONTINUE IN RI/EASTERN MASS IN
MARINE EAST FLOW. VFR IN THE WEST.

TUESDAY...VFR WITH SCATTERED MVFR IN ANY RAIN/SNOW SHOWERS.

WEDNESDAY...CONDITIONS LOWERING TO IFR IN RAIN/HEAVY RAIN. ISOLATED
THUNDERSTORMS POSSIBLE ESPECIALLY WEDNESDAY NIGHT. EAST-SOUTHEST
SURFACE WINDS MAY GUST TO 35 KNOTS ALONG THE EAST MASSACHUSETTS
COAST. WINDS AT 2000 FEET AGL WILL REACH 50-60 KNOTS WEDNESDAY
AFTERNOON AND EARLY NIGHT CREATING LOW LEVEL WIND SHEAR CONCERNS.

CHRISTMAS DAY...WEST WIND GUSTING 30-40 KNOTS. CONDITIONS IMPROVING
TO VFR AS THE WIND BRINGS IN COOLER DRIER AIR.
&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

HIGH CONFIDENCE. HIGH PRESSURE ACROSS QUEBEC WILL RESULT IN
PERSISTENT NORTHEAST WINDS ACROSS THE WATERS THROUGH THE WEEKEND.
WIND GUSTS UP TO 20 KNOTS WITH SEAS BETWEEN 2 AND 4 FEET ARE
EXPECTED FOR MOST WATERS...SO NO HEADLINES PLANNED.

THERE IS A LOW PROBABILITY THAT A BRIEF SURGE OF NORTHEAST WIND
GUSTS NEAR 25 KNOTS WITH MARGINAL 5 FOOT SEAS COULD AFFECT OUR
NORTHERN WATERS LATE TONIGHT INTO SUN MORNING...BUT NOT CONFIDENT
ENOUGH TO ISSUE ANY HEADLINES AT THIS POINT.

OUTLOOK...SUNDAY NIGHT THROUGH THURSDAY...MODERATE CONFIDENCE

SUNDAY NIGHT-MONDAY...EAST TO NORTHEAST WINDS GUSTING AROUND 15
KNOTS OR LESS.  SEAS WILL HOLD AROUND 3-4 FEET.

TUESDAY... INCREASING EAST WINDS WITH FREQUENT GUSTS 25 TO 30 KNOTS.
SEAS WILL BUILD TO 5-6 FEET ON THE EXPOSED WATERS.  A SMALL CRAFT
ADVISORY MAY BE NEEDED.

WEDNESDAY...RAIN WILL BE HEAVY AT TIMES PRODUCING POOR VISIBILITY.
INCREASING SOUTHEAST WINDS 20-25 SUSTAINED AND 40 KNOT GUSTS.  WINDS
SHOULD SHIFT TO SOUTH WEDNESDAY NIGHT AND SOUTHWEST TOWARD THURSDAY
MORNING. RAIN WILL TAPER OFF WITH THE WIND SHIFT TO SOUTHWEST. SEAS
WILL CONTINUE TO BUILD WITH 5-10 FEET HEIGHTS ON THE EXPOSED WATERS.
A GALE WARNING MAY BE NEEDED.

CHRISTMAS DAY... WEST SOUTHWEST WINDS WILL CONTINUE TO GUST 35-40
KNOTS...SO A GALE WARNING MAY CONTINUE TO BE NEEDED. SEAS OF 10-15
FEET ARE POSSIBLE ON THE EXPOSED WATERS...AND 5 FEET IS POSSIBLE ON
SOME OF THE NEARSHORE WATERS.

&&

.TIDES/COASTAL FLOODING... HIGH ASTRONOMICAL TIDES WILL OCCUR
TUESDAY THROUGH THURSDAY. BREAKING IT DOWN...ON TUESDAY HIGH TIDE
AT BOSTON WILL BE 11.6 FT. THERE WILL BE EAST WINDS DURING THIS
HIGH TIDE ALLOWING FOR MINOR SPLASHOVER ALONG THE MASS COAST. IF
WIND GUSTS INCREASE THEN COULD POSSIBLE SEE MINOR COASTAL
FLOODING.

ON WEDNESDAY...WINDS WILL SWITCH TO A MORE SOUTHEASTERLY FLOW DURING
THE DAY AND INCREASE QUICKLY DUE TO THE APPROACHING SYSTEM.
WEDNESDAY AFTERNOON HIGH TIDE IN BOSTON IS 11.7 FT...AND AN
APPRECIABLE EAST OR SOUTHEAST WIND SHOULD PUSH LEVELS HIGHER THAN ON
TUESDAY.  THIS WOULD PROBABLY BE THE BEST CHACNE OF MINOR COASTAL
FLOODING ALONG THE EAST COAST.

THE WEDNESDAY EVENING HIGH TIDE WILL BE A LITTLE LOWER...BUT THE
WIND BECOMES SOUTH WITH 50-60 KNOTS AT 2000 FEET ABOVE THE SURFACE
AVAILABLE TO BE BROUGHT DOWN IN GUSTS. HIGH TIDE IN PROVIDENCE WILL
BE 5.2 FT. MINOR COASTAL FLOODING COULD OCCUR ALONG THE SOUTH
COASTS OF RI AND MASS...AND COULD BE CHANNELED IN NORTH-SOUTH AXIS
BAYS SUCH AS NARRAGANSETT BAY.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...WTB/RLG
NEAR TERM...RLG
SHORT TERM...RLG
LONG TERM...WTB
AVIATION...WTB/RLG
MARINE...WTB/RLG
TIDES/COASTAL FLOODING...




000
FXUS61 KBOX 202147
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
447 PM EST SAT DEC 20 2014

.SYNOPSIS...
SCATTERED SNOW/RAIN SHOWERS WILL GRADUALLY OVERSPREAD THE REGION
FROM EAST TO WEST THIS AFTERNOON THROUGH SUN. WEAK LOW PRESSURE
WILL PASS SOUTH OF NEW ENGLAND BRINGING ANOTHER PERIOD OF
PRECIPITATION MONDAY NIGHT AND TUESDAY. A MUCH STRONGER STORM
PASSING WEST OF NEW ENGLAND WILL BRING HEAVY RAINFALL...GUSTY
WINDS AND COASTAL FLOODING CONCERNS TO THE REGION WEDNESDAY
AND WEDNESDAY NIGHT. DRY BUT VERY WINDY CONDITIONS FOLLOW FOR
CHRISTMAS DAY.

&&

.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
AN INVERTED TROUGH WILL DEVELOP THIS EVENING IN RESPONSE TO A
SHORTWAVE MOVING ACROSS SOUTHERN NEW ENGLAND.  THIS WILL PROVIDE A
FOCUS FOR RAIN/SNOW SHOWERS ACROSS MUCH OF EASTERN MASSACHUSETTS
BEGINNING THIS AFTERNOON AND CONTINUING THROUGH TONIGHT.  WHILE SNOW
SHOWERS MAY REACH INTO WESTERN NEW ENGLAND TONIGHT...A COASTAL FRONT
WILL DEVELOP...AIDING IN FOCUSING SHOWERS ALONG THE EAST COAST OF
MASSACHUSETTS.

SNOW SHOWERS WILL BECOME MORE WIDESPREAD TONIGHT AS THE LOW LEVELS
MOISTEN UP A BIT MORE. LOOKS LIKE IT WILL LIKELY BE WARM ENOUGH
ACROSS THE CAPE AND SOUTHEASTERN PLYMOUTH COUNTY FOR SHOWERS TO BE
RAIN RATHER THAN SNOW.

OVERALL...EXPECTING 1-2 INCHES OF SNOW AT MOST ACROSS EASTERN
MASSACHUSETTS AND RHODE ISLAND.  THERE ARE SEVERAL POTENTIAL PLACES
WHERE LOCALIZED SLIGHTLY HIGHER AMOUNTS /POSSIBLY UP TO 2-4 INCHES/
ARE POSSIBLE.  LOOKING AT THE HIGH RES MODELS...EITHER ACROSS ESSEX
COUNTY AND CAPE ANN...EASTERN NORFOLK COUNTY INTO NORTHERN PLYMOUTH
COUNTY...OR BOTH. THEN THE HIGHER TERRAIN OF WORCESTER COUNTY AND
PROVIDENCE COUNTY MAY SEE SLIGHTLY HIGHER AMOUNTS GIVEN THE UPSLOPE
COMPONENT OF THE WINDS.

SOME OF THE HIGH RES MODELS HAVE A DECENT CLIP OF QPF INTO ESSEX
COUNTY...WHILE OTHERS HAVE NOTHING IN THE SAME AREA.  FOR NORFOLK
AND PLYMOUTH COUNTY...WE MAY SEE A BIT OF OCEAN ENHANCEMENT THAT
RAISES SNOW AMOUNTS IN THOSE AREAS.  DUE TO THE UNCERTAINTY AND THE
LOCALIZED NATURE OF THE POTENTIAL HIGHER AMOUNTS...AM OPTING NOT TO
ISSUE A WINTER WEATHER ADVISORY. INSTEAD...REISSUED THE SPECIAL
WEATHER STATEMENT FOR SNOW. ANYONE OUT AND ABOUT THIS EVENING IN
EASTERN MASSACHUSETTS WILL WANT TO USE CAUTION AS THERE MAY BE
SLIPPERY PATCHES.

&&

.SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
RAIN/SNOW SHOWERS WILL CONTINUE INTO THE MORNING HOURS...THEN TAPER
OFF AS INVERTED TROUGH PULLS AWAY FROM SOUTHERN NEW ENGLAND AND HIGH
PRESSURE STARTS TO BUILD IN.  MOST LIKELY AREAS FOR CONTINUING
SHOWERS WILL BE ALONG THE IMMEDIATE EAST COAST OF MASSACHUSETTS.

AS THE DAY GOES ON...EXPECT A SLOW DRYING TREND AS HIGH PRESSURE
BUILDS INTO THE REGION.  CLOUDS WILL STICK AROUND WITH TEMPS
GENERALLY IN THE 30S.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...

BIG PICTURE... SHORTWAVE ENTERING THE PACIFIC NORTHWEST CROSSES THE
ROCKIES OVER THE WEEKEND DRIVEN BY A 160-KNOT JET.  THIS DIGS A
SUBSTANTIAL TROUGH OVER THE PLAINS MONDAY-TUESDAY WHILE PACIFIC HIGH
PRESSURE BUILDS ALONG THE PACIFIC COAST. THIS IN TURN WILL ALLOW AN
UPPER RIDGE TO BUILD ALONG THE ATLANTIC COAST AND SLOWLY SHIFT EAST
OF THE COAST.  THE JET ENERGY WORKS ITS WAY AROUND THE BASE OF THE
PLAINS TROUGH AND MOVES UP THE APPALACHANS MIDWEEK.  THIS SUPPORTS A
TRANSITION OF THE TROUGH TO NEGATIVE TILT AND SLOWER MOVEMENT...WITH
WARM MOIST AIR FOR THE ATLANTIC COAST. THE TROUGH AXIS SWINGS OVER
NEW ENGLAND CHRISTMAS DAY FOLLOWED BY A WEAK RIDGE. ANOTHER
SHORTWAVE MOVES ASHORE FROM THE PACIFIC MIDWEEK AND MOVES ACROSS THE
PLAINS BY THE END OF THE WEEK AND APPROACHES THE NORTHEAST USA
SATURDAY.

THERE IS SOME SPREAD IN DETAILS AMONG THE LONG RANGE MODELS...BUT
ALL SHOW A SIMILAR SCENARIO BOTH FOR THE MIDWEEK SYSTEM AND THE END
OF WEEK SYSTEM.  WE USED A BLEND OF GFS/ECMWF.

THE DAILIES...

SUNDAY NIGHT-MONDAY... HIGH PRESSURE REMAINS NORTH OF THE REGION
BRINGING A MOIST EAST FLOW ACROSS SOUTHERN NEW ENGLAND. UPPER
PATTERN SHOWS WEAK RIDGING AS THE PLAINS TROUGH DIGS...BUT SURFACE
FIELDS SUGGEST A LINGERING INVERTED TROUGH ALONG OR JUST OFFSHORE.
THIS SHOULD MAINTAIN CONSIDERABLE CLOUDS. COULD BE SOME DRIZZLE OR
FLURRIES NEAR THE EAST COAST BUT SUPPORTING LARGE SCALE ASCENT IS
LACKING SO PCPN SHOULD BE LIMITED.

MONDAY NIGHT-TUESDAY... LOW PRESSURE FORMS ALONG A STALLED WARM
FRONT OFF THE MID ATLANTIC COAST. AS THE LOW DEVELOPS...IT BRINGS
AN INCREASED PRESSURE GRADIENT AGAINST HIGH PRESSURE MOVING
THROUGH THE MARITIMES. THE RESULT WILL BE A STRENGTHENING LOW
LEVEL EAST- SOUTHEAST JET. THIS WILL INCREASE THE MOIST INFLOW
OVER SOUTHERN NEW ENGLAND. ALSO...AS THE JET CONVERGES ON THE
INVERTED SURFACE TROUGH IT WILL GENERATE INCREASED LOW LEVEL LIFT
AND INCREASE THE CHANCE OF PCPN. WE WILL HAVE CLOUDS AND CHANCE
POPS. TEMPS IN NORTHWEST MASS WILL BE COLD ENOUGH SO THAT THERE
MAY BE A MIX OF PCPN TYPES DURING THE MORNING.

TUESDAY NIGHT-WEDNESDAY... PLAINS UPPER TROUGH DIGS DEEPER AND MOVES
EAST...PUSHING THE UPPER RIDGE TO OUR EAST. ALSO...THE STRONG UPPER
SOUTHWEST JET MOVES UP OVER THE EASTERN USA. THIS SETUP WILL TAKE
THE PRIMARY SURFACE LOW UP THROUGH THE WESTERN GREAT LAKES.
SECONDARY LOWS FORMING ON THE SYSTEM COLD FRONT WILL MOVE OUT OF THE
GULF OF MEXICO TOWARD THE GREAT LAKES. A SOUTHWEST LOW LEVEL JET
WILL MOVE UP THE ATLANTIC COAST ON WEDNESDAY AND OVER THE TOP OF THE
EAST-SOUTHEAST FLOW AT THE SURFACE. THE RESULT WILL BE PLENTY OF LOW
LEVEL LIFT THE GENERATE PCPN.

PRECIPITABLE WATER VALUES ARE FORECAST TO EXCEED 1.5 INCHES...WHICH
IS 3 STD DEVIATIONS ABOVE NORMAL FOR DECEMBER.  THIS MEANS A LOT OF
WATER AVAILABLE AS PCPN. TEMPERATURE PROFILES WILL BE ABOVE FREEZING
SO PTYPE SHOULD BE RAIN. MODEL QPF SHOWS POTENTIAL RAINFALL OF OVER
2 INCHES. THIS WOULD SUGGEST POTENTIAL URBAN/POOR DRAINAGE FLOODING
ISSUES WEDNESDAY.

STRONG LOW LEVEL WINDS WILL ALSO BE A CONCERN ESPECIALLY WEDNESDAY
NIGHT. THE ECMWF SHOWS EAST-SOUTHEAST WINDS 30-35 KNOTS ALONG HE
EAST MASS COAST AT 1000 MB. THEN WEDNESDAY NIGHT WINDS AT 925 MB
INCREASE TO 60-75 KNOTS AND MOVE ACROSS COASTAL RI AND SOUTHEAST
MASS. STRONG DOWNPOURS MAY OVERCOME THE LOW LEVEL INVERSION AND
BRING STRONG GUSTS OF AT LEAST 30-40 KNOTS ESPECIALLY ALONG THE
SOUTH COAST. A WIND ADVISORY MAY BE NEEDED IN SOME AREAS.

MAINTAINED A LIMITED MENTION OF THUNDER...AS CONVECTIVE PARAMETERS
ARE MARGINAL...SI VALUES WILL BE JUST ABOVE ZERO AND K INDEX WILL BE
IN THE LOW 30S WEDNESDAY NIGHT.

UPPER LOW WILL SWING THE SURFACE COLD FRONT THROUGH SOUTHERN NEW
ENGLAND WEDNESDAY NIGHT. WINDS WILL THEN SHIFT TO WEST AND PCPN
SHOULD COME TO AN END AROUND THE TIME THAT SANTA ARRIVES.

CHRISTMAS DAY... WEST WINDS WILL BRING A DRYING OF THE AIRMASS
DURING THE DAY. SO THE TREND SHOULD BE TO AT LEAST PARTIAL CLEARING.
SUFFICIENT COLD ADVECTION AT ALL LEVELS THURSDAY WILL ALLOW SOME
MIXING.  WINDS IN THE SFC-850 MB LAYER WILL BE 30-40 KNOTS AND
POSSIBLY A LITTLE HIGHER...WHICH WOULD REQUIRE A WIND ADVISORY FOR
MUCH OF THE AREA.

FRIDAY-SATURDAY... WEAK HIGH PRESSURE BUILDS OVER THE AREA FRIDAY
AND BRING A SUNNY DAY. THE NEXT PACIFIC SHORTWAVE APPROACHES
SATURDAY AND SHOULD BRING INCREASING CLOUDS FROM WEST TO EAST ALONG
WITH A CHANCE OF RAIN OR SNOW SHOWERS MAINLY IN THE AFTERNOON AND AT
NIGHT.

&&

.AVIATION /22Z SATURDAY THROUGH THURSDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH SUNDAY/...

THROUGH 00Z...MODERATE CONFIDENCE. MVFR CIGS WILL CONTINUE TO
OVERSPREAD EASTERN NEW ENGLAND AND EVENTUALLY OVERSPREAD THE INTERIOR
THIS AFTERNOON. SCATTERED SHOWERS ACROSS PORTIONS OF EASTERN
MASSACHUSETTS THIS AFTERNOON. MAINLY SNOW SHOWERS TO THE NORTH AND
WEST OF CAPE COD CANAL...RAIN SHOWERS SOUTH AND EAST. LOCALIZED
IFR CONDITIONS POSSIBLE JUST INLAND FROM THE SOUTHEAST NEW ENGLAND
COAST...WHERE SNOW IS FALLING.

TONIGHT AND SUNDAY...MODERATE CONFIDENCE.  MVFR CONDITIONS DOMINATE
IN LOWER CLOUDS AND SCATTERED SHOWERS. LOCALIZED IFR CONDITIONS
POSSIBLE WITH THE BEST CHANCE IN SNOW SHOWERS. PRECIPITATION
AFFECTS MAINLY EASTERN NEW ENGLAND BUT STILL SOME SCATTERED
ACTIVITY ACROSS WESTERN NEW ENGLAND. MAINLY SNOW SHOWERS TO THE
NORTH AND WEST OF CAPE COD CANAL...RAIN SHOWERS SOUTH AND EAST.

KBOS TERMINAL...MODERATE CONFIDENCE IN TAF. FLURRIES AND SNOW
SHOWERS MAY AFFECT THE TERMINAL BY 21Z.

KBDL TERMINAL...MODERATE CONFIDENCE IN TAF.

OUTLOOK...SUNDAY NIGHT THROUGH THURSDAY...MODERATE CONFIDENCE

SUNDAY NIGHT-MONDAY...MVFR CIGS CONTINUE IN RI/EASTERN MASS IN
MARINE EAST FLOW. VFR IN THE WEST.

TUESDAY...VFR WITH SCATTERED MVFR IN ANY RAIN/SNOW SHOWERS.

WEDNESDAY...CONDITIONS LOWERING TO IFR IN RAIN/HEAVY RAIN. ISOLATED
THUNDERSTORMS POSSIBLE ESPECIALLY WEDNESDAY NIGHT. EAST-SOUTHEST
SURFACE WINDS MAY GUST TO 35 KNOTS ALONG THE EAST MASSACHUSETTS
COAST. WINDS AT 2000 FEET AGL WILL REACH 50-60 KNOTS WEDNESDAY
AFTERNOON AND EARLY NIGHT CREATING LOW LEVEL WIND SHEAR CONCERNS.

CHRISTMAS DAY...WEST WIND GUSTING 30-40 KNOTS. CONDITIONS IMPROVING
TO VFR AS THE WIND BRINGS IN COOLER DRIER AIR.
&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

HIGH CONFIDENCE. HIGH PRESSURE ACROSS QUEBEC WILL RESULT IN
PERSISTENT NORTHEAST WINDS ACROSS THE WATERS THROUGH THE WEEKEND.
WIND GUSTS UP TO 20 KNOTS WITH SEAS BETWEEN 2 AND 4 FEET ARE
EXPECTED FOR MOST WATERS...SO NO HEADLINES PLANNED.

THERE IS A LOW PROBABILITY THAT A BRIEF SURGE OF NORTHEAST WIND
GUSTS NEAR 25 KNOTS WITH MARGINAL 5 FOOT SEAS COULD AFFECT OUR
NORTHERN WATERS LATE TONIGHT INTO SUN MORNING...BUT NOT CONFIDENT
ENOUGH TO ISSUE ANY HEADLINES AT THIS POINT.

OUTLOOK...SUNDAY NIGHT THROUGH THURSDAY...MODERATE CONFIDENCE

SUNDAY NIGHT-MONDAY...EAST TO NORTHEAST WINDS GUSTING AROUND 15
KNOTS OR LESS.  SEAS WILL HOLD AROUND 3-4 FEET.

TUESDAY... INCREASING EAST WINDS WITH FREQUENT GUSTS 25 TO 30 KNOTS.
SEAS WILL BUILD TO 5-6 FEET ON THE EXPOSED WATERS.  A SMALL CRAFT
ADVISORY MAY BE NEEDED.

WEDNESDAY...RAIN WILL BE HEAVY AT TIMES PRODUCING POOR VISIBILITY.
INCREASING SOUTHEAST WINDS 20-25 SUSTAINED AND 40 KNOT GUSTS.  WINDS
SHOULD SHIFT TO SOUTH WEDNESDAY NIGHT AND SOUTHWEST TOWARD THURSDAY
MORNING. RAIN WILL TAPER OFF WITH THE WIND SHIFT TO SOUTHWEST. SEAS
WILL CONTINUE TO BUILD WITH 5-10 FEET HEIGHTS ON THE EXPOSED WATERS.
A GALE WARNING MAY BE NEEDED.

CHRISTMAS DAY... WEST SOUTHWEST WINDS WILL CONTINUE TO GUST 35-40
KNOTS...SO A GALE WARNING MAY CONTINUE TO BE NEEDED. SEAS OF 10-15
FEET ARE POSSIBLE ON THE EXPOSED WATERS...AND 5 FEET IS POSSIBLE ON
SOME OF THE NEARSHORE WATERS.

&&

.TIDES/COASTAL FLOODING... HIGH ASTRONOMICAL TIDES WILL OCCUR
TUESDAY THROUGH THURSDAY. BREAKING IT DOWN...ON TUESDAY HIGH TIDE
AT BOSTON WILL BE 11.6 FT. THERE WILL BE EAST WINDS DURING THIS
HIGH TIDE ALLOWING FOR MINOR SPLASHOVER ALONG THE MASS COAST. IF
WIND GUSTS INCREASE THEN COULD POSSIBLE SEE MINOR COASTAL
FLOODING.

ON WEDNESDAY...WINDS WILL SWITCH TO A MORE SOUTHEASTERLY FLOW DURING
THE DAY AND INCREASE QUICKLY DUE TO THE APPROACHING SYSTEM.
WEDNESDAY AFTERNOON HIGH TIDE IN BOSTON IS 11.7 FT...AND AN
APPRECIABLE EAST OR SOUTHEAST WIND SHOULD PUSH LEVELS HIGHER THAN ON
TUESDAY.  THIS WOULD PROBABLY BE THE BEST CHACNE OF MINOR COASTAL
FLOODING ALONG THE EAST COAST.

THE WEDNESDAY EVENING HIGH TIDE WILL BE A LITTLE LOWER...BUT THE
WIND BECOMES SOUTH WITH 50-60 KNOTS AT 2000 FEET ABOVE THE SURFACE
AVAILABLE TO BE BROUGHT DOWN IN GUSTS. HIGH TIDE IN PROVIDENCE WILL
BE 5.2 FT. MINOR COASTAL FLOODING COULD OCCUR ALONG THE SOUTH
COASTS OF RI AND MASS...AND COULD BE CHANNELED IN NORTH-SOUTH AXIS
BAYS SUCH AS NARRAGANSETT BAY.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...WTB/RLG
NEAR TERM...RLG
SHORT TERM...RLG
LONG TERM...WTB
AVIATION...WTB/RLG
MARINE...WTB/RLG
TIDES/COASTAL FLOODING...




000
FXUS61 KGYX 202049
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
349 PM EST SAT DEC 20 2014

.SYNOPSIS...
HIGH PRESSURE BUILDS OVER NORTHERN MAINE SUNDAY...ALLOWING THE
FLOW TO TURN ONSHORE. A WEAK WEATHER DISTURBANCE MAY TRIGGER SOME
FLURRIES OR LIGHT SNOW OVER SOUTHERN REGIONS RIGHT THROUGH MONDAY.
A WEAK AREA OF LOW PRESSURE WILL MOVE UP THE COAST TUESDAY...WITH
A MORE SIGNIFICANT SYSTEM GRADUALLY ORGANIZING WEDNESDAY...BEFORE
MOVING OVER THE GREAT LAKES. THIS COULD BRING WINDY CONDITIONS AND
THE POTENTIAL FOR HEAVY RAIN AROUND CHRISTMAS EVE INTO EARLY
CHRISTMAS MORNING.


&&

.NEAR TERM /THROUGH TONIGHT/...
SC CONTINUES TO POUR IN OFF THE GULF OF MAINE LATE THIS AFTERNOON.
SCATTERED SNOW SHOWERS WILL REMAIN OFFSHORE FOR A FEW MORE HOURS
PER LATEST RADAR TRENDS. HOWEVER...SOME PRECIP WILL BEGIN TO ENTER
THE SEACOAST OF NH THIS EVENING. 12Z MESOSCALE MODEL SUITE
CONTINUES TO SHOW THESE SNOW SHOWERS BECOMING PERSISTENT ENOUGH TO
DROP A LIGHT COATING OF SNOW IN THE MHT THROUGH PSM CORRIDOR.

WITH MAINLY CLEAR SKIES UP NORTH...EXPECT ANOTHER COLD NIGHT WITH
LOWS IN THE SINGLE NUMBERS. SOME AREAS IN THE NORTH WERE BELOW
ZERO THIS MORNING.

&&

.SHORT TERM /SUNDAY AND SUNDAY NIGHT/...
SNOW SHOWERS MAY BE PERSISTENT OVER SRN NH EARLY SUNDAY DUE TO
OCEAN EFFECT...WITH DRYING OCCURRING DURING THE AFTERNOON. THE
PASSAGE OF A WEAK UPPER LEVEL LOW OVER EASTERN AREAS MAY BRING A
SNOW SHOWER OR TWO TO THE MIDCOAST AREA OF MAINE.

SOME CLEARING WILL OCCUR SUNDAY NIGHT AS THE WEAK SYSTEM SHIFTS TO
THE EAST. HOWEVER...A LOW LEVEL NORTHEAST FLOW WILL
CONTINUE...WHICH WILL ALLOW FOR THE POSSIBILITY OF A LIGHT SNOW
SHOWER ALONG THE COAST AND SOME LOW CLOUDINESS. THIS WILL KEEP MIN
TEMPS ALONG THE COAST IN THE MID TO UPPER 20S...WHILE THE
MOUNTAINS DROP OFF INTO THE LOWER TO MIDDLE TEENS.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
THE WEAK ONSHORE FLOW CONTINUES MONDAY INTO TUE WITH LOW LEVEL
MOISTURE DEEPEST ALONG THE COAST. SOME PERIODS OF LIGHT SNOW OR DRIZZLE
OR EVEN SOME FRZG DRIZZLE ARE POSSIBLE MON AND MON NIGHT. ON TUE
THE WARMER ONSHORE FLOW DEEPENS AS THE HIGH MOVES FURTHER
OFFSHORE ALLOWING A SELY FLOW TO INCREASE...SO CAN`T RULE OUT
SOME LIGHT IMTERMITTENT PCPN. THE MAIN EVENT WILL BE THE ONSET OF
THE HEAVIER PRECIPITATION LATE CHRISTMAS EVE AND ESPECIALLY
CHRISTMAS DAY AND NIGHT WHERE THE RAIN WILL BECOME HEAVY AT TIMES
AS A STRONG WAA PATTERN DEVELOPS BEING ACCOMPANIED BY A STRONG
LOW/MID LEVEL JET AS THE MAIN UPPER LOW PASSES WELL TO OUR W AS IT
MOVES THROUGH THE GREAT LAKES. QPF TOTALS FOR LATE TUE INTO THU
COULD BE IN THE 2-4 INCH RANGE AND DUE TO VERY WARM AIR THIS WILL
BE IN THE FORM OF RAIN EVEN IN THE MOUNTAINS. SOME FLOODING
PROBLEMS MAY ARISE IN THE HEADWATERS BY WED NIGHT OR THU DUE TO
THE COMBINATION OF SNOWMELT AND THE HEAVY RAINS. ALL MODELS AGREE
ON MILD TEMPS...USED A BLEND OF THE MODELS.

SYSTEM FINALLY WINDS DOWN BY THURSDAY AFTERNOON AS A DRY SLOT
MOVES ACROSS THE AREA.

ANOTHER SYSTEM WHICH WILL BE WEAKER APPROACHES FOR THE WEEKEND
WHICH ALSO LOOKS WARM AND WET.

&&

.AVIATION /19Z SATURDAY THROUGH THURSDAY/...
SHORT TERM...VFR CONDITIONS...WITH POSSIBLY MVFR CONDITIONS
BRIEFLY IN ANY SNOW SHOWERS OVER SOUTHERNMOST NH TONIGHT AND
SUNDAY.

LONG TERM...POSSIBLE PERIODS OF MVFR TO IFR AT COASTAL TERMINALS
MONDAY AS INVERTED TROUGH DEVELOPS ACROSS THE GULF OF ME. MVFR
LIKELY TO HOLD TUE INTO TUE NIGHT...LOWERING TO IFR LATE TUE
NIGHT INTO THU IN RAIN...WITH INCREASING E-SE WINDS WED.

&&

.MARINE...
SHORT TERM...A FEW WIND GUSTS CONTINUE JUST BELOW 25 KTS THIS
AFTERNOON...WITH WAVES 4` OR LOWER...THEREFORE NO FLAGS IN THE
NEAR TERM. WINDS SHOULD CONTINUE TO SLOWLY DECREASE TONIGHT INTO
TOMORROW FROM THE NORTHEAST.

LONG TERM...STRONG LOW PRES WILL MOVE WELL TO THE WEST AND WILL
CAUSE WINDS TO INCREASE TO GALES TUE NIGHT THROUGH WED WITH
BORDERLINE STORM FORCE WINDS POSSIBLE WED NIGHT. SEAS COULD BUILD
IN EXCESS OF 15 FT OVER THE OUTER WATERS BY WED NIGHT. GUIDANCE
LOOKS LOW ON BOTH WINDS AND SEAS WHICH IS TYPICAL FOR THESE TYPE
OF EVENTS.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.

&&

$$




000
FXUS61 KGYX 202049
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
349 PM EST SAT DEC 20 2014

.SYNOPSIS...
HIGH PRESSURE BUILDS OVER NORTHERN MAINE SUNDAY...ALLOWING THE
FLOW TO TURN ONSHORE. A WEAK WEATHER DISTURBANCE MAY TRIGGER SOME
FLURRIES OR LIGHT SNOW OVER SOUTHERN REGIONS RIGHT THROUGH MONDAY.
A WEAK AREA OF LOW PRESSURE WILL MOVE UP THE COAST TUESDAY...WITH
A MORE SIGNIFICANT SYSTEM GRADUALLY ORGANIZING WEDNESDAY...BEFORE
MOVING OVER THE GREAT LAKES. THIS COULD BRING WINDY CONDITIONS AND
THE POTENTIAL FOR HEAVY RAIN AROUND CHRISTMAS EVE INTO EARLY
CHRISTMAS MORNING.


&&

.NEAR TERM /THROUGH TONIGHT/...
SC CONTINUES TO POUR IN OFF THE GULF OF MAINE LATE THIS AFTERNOON.
SCATTERED SNOW SHOWERS WILL REMAIN OFFSHORE FOR A FEW MORE HOURS
PER LATEST RADAR TRENDS. HOWEVER...SOME PRECIP WILL BEGIN TO ENTER
THE SEACOAST OF NH THIS EVENING. 12Z MESOSCALE MODEL SUITE
CONTINUES TO SHOW THESE SNOW SHOWERS BECOMING PERSISTENT ENOUGH TO
DROP A LIGHT COATING OF SNOW IN THE MHT THROUGH PSM CORRIDOR.

WITH MAINLY CLEAR SKIES UP NORTH...EXPECT ANOTHER COLD NIGHT WITH
LOWS IN THE SINGLE NUMBERS. SOME AREAS IN THE NORTH WERE BELOW
ZERO THIS MORNING.

&&

.SHORT TERM /SUNDAY AND SUNDAY NIGHT/...
SNOW SHOWERS MAY BE PERSISTENT OVER SRN NH EARLY SUNDAY DUE TO
OCEAN EFFECT...WITH DRYING OCCURRING DURING THE AFTERNOON. THE
PASSAGE OF A WEAK UPPER LEVEL LOW OVER EASTERN AREAS MAY BRING A
SNOW SHOWER OR TWO TO THE MIDCOAST AREA OF MAINE.

SOME CLEARING WILL OCCUR SUNDAY NIGHT AS THE WEAK SYSTEM SHIFTS TO
THE EAST. HOWEVER...A LOW LEVEL NORTHEAST FLOW WILL
CONTINUE...WHICH WILL ALLOW FOR THE POSSIBILITY OF A LIGHT SNOW
SHOWER ALONG THE COAST AND SOME LOW CLOUDINESS. THIS WILL KEEP MIN
TEMPS ALONG THE COAST IN THE MID TO UPPER 20S...WHILE THE
MOUNTAINS DROP OFF INTO THE LOWER TO MIDDLE TEENS.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
THE WEAK ONSHORE FLOW CONTINUES MONDAY INTO TUE WITH LOW LEVEL
MOISTURE DEEPEST ALONG THE COAST. SOME PERIODS OF LIGHT SNOW OR DRIZZLE
OR EVEN SOME FRZG DRIZZLE ARE POSSIBLE MON AND MON NIGHT. ON TUE
THE WARMER ONSHORE FLOW DEEPENS AS THE HIGH MOVES FURTHER
OFFSHORE ALLOWING A SELY FLOW TO INCREASE...SO CAN`T RULE OUT
SOME LIGHT IMTERMITTENT PCPN. THE MAIN EVENT WILL BE THE ONSET OF
THE HEAVIER PRECIPITATION LATE CHRISTMAS EVE AND ESPECIALLY
CHRISTMAS DAY AND NIGHT WHERE THE RAIN WILL BECOME HEAVY AT TIMES
AS A STRONG WAA PATTERN DEVELOPS BEING ACCOMPANIED BY A STRONG
LOW/MID LEVEL JET AS THE MAIN UPPER LOW PASSES WELL TO OUR W AS IT
MOVES THROUGH THE GREAT LAKES. QPF TOTALS FOR LATE TUE INTO THU
COULD BE IN THE 2-4 INCH RANGE AND DUE TO VERY WARM AIR THIS WILL
BE IN THE FORM OF RAIN EVEN IN THE MOUNTAINS. SOME FLOODING
PROBLEMS MAY ARISE IN THE HEADWATERS BY WED NIGHT OR THU DUE TO
THE COMBINATION OF SNOWMELT AND THE HEAVY RAINS. ALL MODELS AGREE
ON MILD TEMPS...USED A BLEND OF THE MODELS.

SYSTEM FINALLY WINDS DOWN BY THURSDAY AFTERNOON AS A DRY SLOT
MOVES ACROSS THE AREA.

ANOTHER SYSTEM WHICH WILL BE WEAKER APPROACHES FOR THE WEEKEND
WHICH ALSO LOOKS WARM AND WET.

&&

.AVIATION /19Z SATURDAY THROUGH THURSDAY/...
SHORT TERM...VFR CONDITIONS...WITH POSSIBLY MVFR CONDITIONS
BRIEFLY IN ANY SNOW SHOWERS OVER SOUTHERNMOST NH TONIGHT AND
SUNDAY.

LONG TERM...POSSIBLE PERIODS OF MVFR TO IFR AT COASTAL TERMINALS
MONDAY AS INVERTED TROUGH DEVELOPS ACROSS THE GULF OF ME. MVFR
LIKELY TO HOLD TUE INTO TUE NIGHT...LOWERING TO IFR LATE TUE
NIGHT INTO THU IN RAIN...WITH INCREASING E-SE WINDS WED.

&&

.MARINE...
SHORT TERM...A FEW WIND GUSTS CONTINUE JUST BELOW 25 KTS THIS
AFTERNOON...WITH WAVES 4` OR LOWER...THEREFORE NO FLAGS IN THE
NEAR TERM. WINDS SHOULD CONTINUE TO SLOWLY DECREASE TONIGHT INTO
TOMORROW FROM THE NORTHEAST.

LONG TERM...STRONG LOW PRES WILL MOVE WELL TO THE WEST AND WILL
CAUSE WINDS TO INCREASE TO GALES TUE NIGHT THROUGH WED WITH
BORDERLINE STORM FORCE WINDS POSSIBLE WED NIGHT. SEAS COULD BUILD
IN EXCESS OF 15 FT OVER THE OUTER WATERS BY WED NIGHT. GUIDANCE
LOOKS LOW ON BOTH WINDS AND SEAS WHICH IS TYPICAL FOR THESE TYPE
OF EVENTS.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.

&&

$$




000
FXUS61 KGYX 202049
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
349 PM EST SAT DEC 20 2014

.SYNOPSIS...
HIGH PRESSURE BUILDS OVER NORTHERN MAINE SUNDAY...ALLOWING THE
FLOW TO TURN ONSHORE. A WEAK WEATHER DISTURBANCE MAY TRIGGER SOME
FLURRIES OR LIGHT SNOW OVER SOUTHERN REGIONS RIGHT THROUGH MONDAY.
A WEAK AREA OF LOW PRESSURE WILL MOVE UP THE COAST TUESDAY...WITH
A MORE SIGNIFICANT SYSTEM GRADUALLY ORGANIZING WEDNESDAY...BEFORE
MOVING OVER THE GREAT LAKES. THIS COULD BRING WINDY CONDITIONS AND
THE POTENTIAL FOR HEAVY RAIN AROUND CHRISTMAS EVE INTO EARLY
CHRISTMAS MORNING.


&&

.NEAR TERM /THROUGH TONIGHT/...
SC CONTINUES TO POUR IN OFF THE GULF OF MAINE LATE THIS AFTERNOON.
SCATTERED SNOW SHOWERS WILL REMAIN OFFSHORE FOR A FEW MORE HOURS
PER LATEST RADAR TRENDS. HOWEVER...SOME PRECIP WILL BEGIN TO ENTER
THE SEACOAST OF NH THIS EVENING. 12Z MESOSCALE MODEL SUITE
CONTINUES TO SHOW THESE SNOW SHOWERS BECOMING PERSISTENT ENOUGH TO
DROP A LIGHT COATING OF SNOW IN THE MHT THROUGH PSM CORRIDOR.

WITH MAINLY CLEAR SKIES UP NORTH...EXPECT ANOTHER COLD NIGHT WITH
LOWS IN THE SINGLE NUMBERS. SOME AREAS IN THE NORTH WERE BELOW
ZERO THIS MORNING.

&&

.SHORT TERM /SUNDAY AND SUNDAY NIGHT/...
SNOW SHOWERS MAY BE PERSISTENT OVER SRN NH EARLY SUNDAY DUE TO
OCEAN EFFECT...WITH DRYING OCCURRING DURING THE AFTERNOON. THE
PASSAGE OF A WEAK UPPER LEVEL LOW OVER EASTERN AREAS MAY BRING A
SNOW SHOWER OR TWO TO THE MIDCOAST AREA OF MAINE.

SOME CLEARING WILL OCCUR SUNDAY NIGHT AS THE WEAK SYSTEM SHIFTS TO
THE EAST. HOWEVER...A LOW LEVEL NORTHEAST FLOW WILL
CONTINUE...WHICH WILL ALLOW FOR THE POSSIBILITY OF A LIGHT SNOW
SHOWER ALONG THE COAST AND SOME LOW CLOUDINESS. THIS WILL KEEP MIN
TEMPS ALONG THE COAST IN THE MID TO UPPER 20S...WHILE THE
MOUNTAINS DROP OFF INTO THE LOWER TO MIDDLE TEENS.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
THE WEAK ONSHORE FLOW CONTINUES MONDAY INTO TUE WITH LOW LEVEL
MOISTURE DEEPEST ALONG THE COAST. SOME PERIODS OF LIGHT SNOW OR DRIZZLE
OR EVEN SOME FRZG DRIZZLE ARE POSSIBLE MON AND MON NIGHT. ON TUE
THE WARMER ONSHORE FLOW DEEPENS AS THE HIGH MOVES FURTHER
OFFSHORE ALLOWING A SELY FLOW TO INCREASE...SO CAN`T RULE OUT
SOME LIGHT IMTERMITTENT PCPN. THE MAIN EVENT WILL BE THE ONSET OF
THE HEAVIER PRECIPITATION LATE CHRISTMAS EVE AND ESPECIALLY
CHRISTMAS DAY AND NIGHT WHERE THE RAIN WILL BECOME HEAVY AT TIMES
AS A STRONG WAA PATTERN DEVELOPS BEING ACCOMPANIED BY A STRONG
LOW/MID LEVEL JET AS THE MAIN UPPER LOW PASSES WELL TO OUR W AS IT
MOVES THROUGH THE GREAT LAKES. QPF TOTALS FOR LATE TUE INTO THU
COULD BE IN THE 2-4 INCH RANGE AND DUE TO VERY WARM AIR THIS WILL
BE IN THE FORM OF RAIN EVEN IN THE MOUNTAINS. SOME FLOODING
PROBLEMS MAY ARISE IN THE HEADWATERS BY WED NIGHT OR THU DUE TO
THE COMBINATION OF SNOWMELT AND THE HEAVY RAINS. ALL MODELS AGREE
ON MILD TEMPS...USED A BLEND OF THE MODELS.

SYSTEM FINALLY WINDS DOWN BY THURSDAY AFTERNOON AS A DRY SLOT
MOVES ACROSS THE AREA.

ANOTHER SYSTEM WHICH WILL BE WEAKER APPROACHES FOR THE WEEKEND
WHICH ALSO LOOKS WARM AND WET.

&&

.AVIATION /19Z SATURDAY THROUGH THURSDAY/...
SHORT TERM...VFR CONDITIONS...WITH POSSIBLY MVFR CONDITIONS
BRIEFLY IN ANY SNOW SHOWERS OVER SOUTHERNMOST NH TONIGHT AND
SUNDAY.

LONG TERM...POSSIBLE PERIODS OF MVFR TO IFR AT COASTAL TERMINALS
MONDAY AS INVERTED TROUGH DEVELOPS ACROSS THE GULF OF ME. MVFR
LIKELY TO HOLD TUE INTO TUE NIGHT...LOWERING TO IFR LATE TUE
NIGHT INTO THU IN RAIN...WITH INCREASING E-SE WINDS WED.

&&

.MARINE...
SHORT TERM...A FEW WIND GUSTS CONTINUE JUST BELOW 25 KTS THIS
AFTERNOON...WITH WAVES 4` OR LOWER...THEREFORE NO FLAGS IN THE
NEAR TERM. WINDS SHOULD CONTINUE TO SLOWLY DECREASE TONIGHT INTO
TOMORROW FROM THE NORTHEAST.

LONG TERM...STRONG LOW PRES WILL MOVE WELL TO THE WEST AND WILL
CAUSE WINDS TO INCREASE TO GALES TUE NIGHT THROUGH WED WITH
BORDERLINE STORM FORCE WINDS POSSIBLE WED NIGHT. SEAS COULD BUILD
IN EXCESS OF 15 FT OVER THE OUTER WATERS BY WED NIGHT. GUIDANCE
LOOKS LOW ON BOTH WINDS AND SEAS WHICH IS TYPICAL FOR THESE TYPE
OF EVENTS.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.

&&

$$




000
FXUS61 KGYX 202049
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
349 PM EST SAT DEC 20 2014

.SYNOPSIS...
HIGH PRESSURE BUILDS OVER NORTHERN MAINE SUNDAY...ALLOWING THE
FLOW TO TURN ONSHORE. A WEAK WEATHER DISTURBANCE MAY TRIGGER SOME
FLURRIES OR LIGHT SNOW OVER SOUTHERN REGIONS RIGHT THROUGH MONDAY.
A WEAK AREA OF LOW PRESSURE WILL MOVE UP THE COAST TUESDAY...WITH
A MORE SIGNIFICANT SYSTEM GRADUALLY ORGANIZING WEDNESDAY...BEFORE
MOVING OVER THE GREAT LAKES. THIS COULD BRING WINDY CONDITIONS AND
THE POTENTIAL FOR HEAVY RAIN AROUND CHRISTMAS EVE INTO EARLY
CHRISTMAS MORNING.


&&

.NEAR TERM /THROUGH TONIGHT/...
SC CONTINUES TO POUR IN OFF THE GULF OF MAINE LATE THIS AFTERNOON.
SCATTERED SNOW SHOWERS WILL REMAIN OFFSHORE FOR A FEW MORE HOURS
PER LATEST RADAR TRENDS. HOWEVER...SOME PRECIP WILL BEGIN TO ENTER
THE SEACOAST OF NH THIS EVENING. 12Z MESOSCALE MODEL SUITE
CONTINUES TO SHOW THESE SNOW SHOWERS BECOMING PERSISTENT ENOUGH TO
DROP A LIGHT COATING OF SNOW IN THE MHT THROUGH PSM CORRIDOR.

WITH MAINLY CLEAR SKIES UP NORTH...EXPECT ANOTHER COLD NIGHT WITH
LOWS IN THE SINGLE NUMBERS. SOME AREAS IN THE NORTH WERE BELOW
ZERO THIS MORNING.

&&

.SHORT TERM /SUNDAY AND SUNDAY NIGHT/...
SNOW SHOWERS MAY BE PERSISTENT OVER SRN NH EARLY SUNDAY DUE TO
OCEAN EFFECT...WITH DRYING OCCURRING DURING THE AFTERNOON. THE
PASSAGE OF A WEAK UPPER LEVEL LOW OVER EASTERN AREAS MAY BRING A
SNOW SHOWER OR TWO TO THE MIDCOAST AREA OF MAINE.

SOME CLEARING WILL OCCUR SUNDAY NIGHT AS THE WEAK SYSTEM SHIFTS TO
THE EAST. HOWEVER...A LOW LEVEL NORTHEAST FLOW WILL
CONTINUE...WHICH WILL ALLOW FOR THE POSSIBILITY OF A LIGHT SNOW
SHOWER ALONG THE COAST AND SOME LOW CLOUDINESS. THIS WILL KEEP MIN
TEMPS ALONG THE COAST IN THE MID TO UPPER 20S...WHILE THE
MOUNTAINS DROP OFF INTO THE LOWER TO MIDDLE TEENS.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
THE WEAK ONSHORE FLOW CONTINUES MONDAY INTO TUE WITH LOW LEVEL
MOISTURE DEEPEST ALONG THE COAST. SOME PERIODS OF LIGHT SNOW OR DRIZZLE
OR EVEN SOME FRZG DRIZZLE ARE POSSIBLE MON AND MON NIGHT. ON TUE
THE WARMER ONSHORE FLOW DEEPENS AS THE HIGH MOVES FURTHER
OFFSHORE ALLOWING A SELY FLOW TO INCREASE...SO CAN`T RULE OUT
SOME LIGHT IMTERMITTENT PCPN. THE MAIN EVENT WILL BE THE ONSET OF
THE HEAVIER PRECIPITATION LATE CHRISTMAS EVE AND ESPECIALLY
CHRISTMAS DAY AND NIGHT WHERE THE RAIN WILL BECOME HEAVY AT TIMES
AS A STRONG WAA PATTERN DEVELOPS BEING ACCOMPANIED BY A STRONG
LOW/MID LEVEL JET AS THE MAIN UPPER LOW PASSES WELL TO OUR W AS IT
MOVES THROUGH THE GREAT LAKES. QPF TOTALS FOR LATE TUE INTO THU
COULD BE IN THE 2-4 INCH RANGE AND DUE TO VERY WARM AIR THIS WILL
BE IN THE FORM OF RAIN EVEN IN THE MOUNTAINS. SOME FLOODING
PROBLEMS MAY ARISE IN THE HEADWATERS BY WED NIGHT OR THU DUE TO
THE COMBINATION OF SNOWMELT AND THE HEAVY RAINS. ALL MODELS AGREE
ON MILD TEMPS...USED A BLEND OF THE MODELS.

SYSTEM FINALLY WINDS DOWN BY THURSDAY AFTERNOON AS A DRY SLOT
MOVES ACROSS THE AREA.

ANOTHER SYSTEM WHICH WILL BE WEAKER APPROACHES FOR THE WEEKEND
WHICH ALSO LOOKS WARM AND WET.

&&

.AVIATION /19Z SATURDAY THROUGH THURSDAY/...
SHORT TERM...VFR CONDITIONS...WITH POSSIBLY MVFR CONDITIONS
BRIEFLY IN ANY SNOW SHOWERS OVER SOUTHERNMOST NH TONIGHT AND
SUNDAY.

LONG TERM...POSSIBLE PERIODS OF MVFR TO IFR AT COASTAL TERMINALS
MONDAY AS INVERTED TROUGH DEVELOPS ACROSS THE GULF OF ME. MVFR
LIKELY TO HOLD TUE INTO TUE NIGHT...LOWERING TO IFR LATE TUE
NIGHT INTO THU IN RAIN...WITH INCREASING E-SE WINDS WED.

&&

.MARINE...
SHORT TERM...A FEW WIND GUSTS CONTINUE JUST BELOW 25 KTS THIS
AFTERNOON...WITH WAVES 4` OR LOWER...THEREFORE NO FLAGS IN THE
NEAR TERM. WINDS SHOULD CONTINUE TO SLOWLY DECREASE TONIGHT INTO
TOMORROW FROM THE NORTHEAST.

LONG TERM...STRONG LOW PRES WILL MOVE WELL TO THE WEST AND WILL
CAUSE WINDS TO INCREASE TO GALES TUE NIGHT THROUGH WED WITH
BORDERLINE STORM FORCE WINDS POSSIBLE WED NIGHT. SEAS COULD BUILD
IN EXCESS OF 15 FT OVER THE OUTER WATERS BY WED NIGHT. GUIDANCE
LOOKS LOW ON BOTH WINDS AND SEAS WHICH IS TYPICAL FOR THESE TYPE
OF EVENTS.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.

&&

$$




000
FXUS61 KBOX 202026
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
326 PM EST SAT DEC 20 2014

.SYNOPSIS...
SCATTERED SNOW/RAIN SHOWERS WILL GRADUALLY OVERSPREAD THE REGION
FROM EAST TO WEST THIS AFTERNOON THROUGH SUN. WEAK LOW PRESSURE
WILL PASS SOUTH OF NEW ENGLAND BRINGING ANOTHER PERIOD OF PRECIP
MON NIGHT AND TUE. A MUCH STRONGER STORM PASSING WEST OF NEW
ENGLAND WILL BRING HEAVY RAINFALL...GUSTY WINDS AND COASTAL
FLOODING CONCERNS TO THE REGION WED INTO WED EVENING. DRY BUT VERY
WINDY CONDITIONS FOLLOW FOR CHRISTMAS DAY INTO FRI.

&&

.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
AN INVERTED TROUGH WILL DEVELOP THIS EVENING IN RESPONSE TO A
SHORTWAVE MOVING ACROSS SOUTHERN NEW ENGLAND.  THIS WILL PROVIDE A
FOCUS FOR RAIN/SNOW SHOWERS ACROSS MUCH OF EASTERN MASSACHUSETTS
BEGINNING THIS AFTERNOON AND CONTINUING THROUGH TONIGHT.  WHILE SNOW
SHOWERS MAY REACH INTO WESTERN NEW ENGLAND TONIGHT...A COASTAL FRONT
WILL DEVELOP...AIDING IN FOCUSING SHOWERS ALONG THE EAST COAST OF
MASSACHUSETTS.

SNOW SHOWERS WILL BECOME MORE WIDESPREAD TONIGHT AS THE LOW LEVELS
MOISTEN UP A BIT MORE. LOOKS LIKE IT WILL LIKELY BE WARM ENOUGH
ACROSS THE CAPE AND SOUTHEASTERN PLYMOUTH COUNTY FOR SHOWERS TO BE
RAIN RATHER THAN SNOW.

OVERALL...EXPECTING 1-2 INCHES OF SNOW AT MOST ACROSS EASTERN
MASSACHUSETTS AND RHODE ISLAND.  THERE ARE SEVERAL POTENTIAL PLACES
WHERE LOCALIZED SLIGHTLY HIGHER AMOUNTS /POSSIBLY UP TO 2-4 INCHES/
ARE POSSIBLE.  LOOKING AT THE HIGH RES MODELS...EITHER ACROSS ESSEX
COUNTY AND CAPE ANN...EASTERN NORFOLK COUNTY INTO NORTHERN PLYMOUTH
COUNTY...OR BOTH. THEN THE HIGHER TERRAIN OF WORCESTER COUNTY AND
PROVIDENCE COUNTY MAY SEE SLIGHTLY HIGHER AMOUNTS GIVEN THE UPSLOPE
COMPONENT OF THE WINDS.

SOME OF THE HIGH RES MODELS HAVE A DECENT CLIP OF QPF INTO ESSEX
COUNTY...WHILE OTHERS HAVE NOTHING IN THE SAME AREA.  FOR NORFOLK
AND PLYMOUTH COUNTY...WE MAY SEE A BIT OF OCEAN ENHANCEMENT THAT
RAISES SNOW AMOUNTS IN THOSE AREAS.  DUE TO THE UNCERTAINTY AND THE
LOCALIZED NATURE OF THE POTENTIAL HIGHER AMOUNTS...AM OPTING NOT TO
ISSUE A WINTER WEATHER ADVISORY. INSTEAD...REISSUED THE SPECIAL
WEATHER STATEMENT FOR SNOW. ANYONE OUT AND ABOUT THIS EVENING IN
EASTERN MASSACHUSETTS WILL WANT TO USE CAUTION AS THERE MAY BE
SLIPPERY PATCHES.

&&

.SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
RAIN/SNOW SHOWERS WILL CONTINUE INTO THE MORNING HOURS...THEN TAPER
OFF AS INVERTED TROUGH PULLS AWAY FROM SOUTHERN NEW ENGLAND AND HIGH
PRESSURE STARTS TO BUILD IN.  MOST LIKELY AREAS FOR CONTINUING
SHOWERS WILL BE ALONG THE IMMEDIATE EAST COAST OF MASSACHUSETTS.

AS THE DAY GOES ON...EXPECT A SLOW DRYING TREND AS HIGH PRESSURE
BUILDS INTO THE REGION.  CLOUDS WILL STICK AROUND WITH TEMPS
GENERALLY IN THE 30S.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
HIGHLIGHTS...

* INVERTED TROUGH WILL BRING RAIN/SNOW SHOWERS TO THE MASS EAST
  COASTLINE MONDAY INTO TUES MORNING.
* WEAK WAVE OF LOW PRESSURE MON NIGHT/TUESDAY COULD BRING WINTRY
  MIX TO INTERIOR
* ANOMALOUS SYSTEM ACROSS THE GREAT LAKES WILL BRING HEAVY
  RAIN...GUSTY WINDS AND COASTAL FLOODING CONCERNS AROUND CHRISTMAS
  EVE

OVERVIEW...

OVERALL 00Z GUIDANCE IS IN AGREEMENT SYNOPTICALLY WITH ISSUES ON
TIMING AND SMALLER SCALE FEATURES. IT REMAINS EVIDENT THAT AN
AMPLIFIED MID-UPPER LEVEL TROUGH AND PCPN FOCUSING LEAD SURFACE
LOW/FRONTAL SYSTEM WILL STEADILY PROGRESS TO THE EAST-CENTRAL U.S.
TUE AS EMBEDDED IMPULSES DIG TO THE LEE OF AN AMPLIFIED ERN
PACIFIC/WEST COAST RIDGE ALOFT. THE SUPPORTING AND INCREASINGLY
NEGATIVE-TILT TROUGH ALOFT WORKS OVER THE ERN US AND OUT THROUGH THE
NERN STATES INTO DAYS 4/5 WED/THU.  MODELS/ENSEMBLES HAVE BEEN
FAIRLY CONSISTENT ON THIS AMPLIFIED PATTERN AND THE MOST RECENT
GEFS/ECMWF ENSEMBLE GUIDANCE SHOW GOOD CORRELATION TO NEXT THURSDAY.

HIGH PRESSURE AND UPPER LEVEL RIDGE OVER THE REGION WILL BEGIN TO
EXIT BY MONDAY. AT THE SURFACE APPEARS ANOTHER INVERTED
TROUGH/ONSHORE FLOW WILL YIELD TO PRECIP ALONG THE MASS COASTLINE ON
MONDAY. ASIDE FROM THIS QUICK MESOSCALE EVENT THE MAIN FOCUS IS ON
THE LONGWAVE DIGGING TROUGH OVER THE CENTRAL CONUS WHICH WILL PUSH A
FEW SHORTWAVES THROUGH THE FLOW. FIRST ONE DEVELOPS A WEAK WAVE
MOVING TOWARDS THE REGION LATE MONDAY INTO TUESDAY. THERE IS STILL
SOME UNCERTAINTY WITH THE LOCATION/STRENGTH OF THIS SYSTEM BUT
APPEARS THAT THERE IS THE POSSIBILITY OF A SNOW/WINTRY MIX IN THE
INTERIOR. AS THIS SYSTEM DEPARTS AN ANOMALOUS LOW OVER THE GREAT
LAKES WILL DEVELOP A SECONDARY LOW JUST WEST OF SOUTHERN NEW ENGLAND
PER ENSEMBLE GUIDANCE. STILL A SOME SPREAD BUT IF THIS DOUBLE LOW
DOES DEVELOP THEN THE RAIN AND WIND ASPECT OF THE SYSTEM
INCREASES...DETAILS BELOW. STILL NEED TO WORK OUT MINOR DETAILS
WITH THIS PARTICULAR SYSTEM BUT WITH 3 TO 4 STANDARD DEVIATIONS
AWAY AND GENERAL MODEL AGREEMENT HAVE HIGH CONFIDENCE THIS SYSTEM
WILL IMPACT SOUTHERN NEW ENGLAND.

DETAILS...

SUNDAY NIGHT INTO TUESDAY...MODERATE CONFIDENCE.

HIGH PRESSURE AND UPPER LEVEL RIDGE WILL BEGIN TO MOVE OFFSHORE AS
DIGGING TROUGH BEGINS TO SET-UP OVER THE CENTRAL CONUS. APPEARS
ANOTHER MESOSCALE INVERTED TROUGH WILL SET UP ON MONDAY AND LAST
INTO EARLY TUESDAY MORNING. GUIDANCE SHOWS THAT RAIN/SNOW SHOWERS
WILL DEVELOP ALONG THE MASS EAST COASTLINE THANKS TO ONSHORE
EASTERLY FLOW. APPEARS THE COLUMN WILL SATURATE PER BUFKIT
SOUNDINGS AND SOUTHERLY FLOW ALOFT. BOTH THE NAM AND GFS SHOW QPF
MAKING IT ONSHORE DURING THIS TIME FRAME. HOWEVER THE EC IS
SLIGHTLY SLOWER AND KEEP THE BULK OF THE PRECIP JUST OFFSHORE. ADD
A CHANCE OF POPS DUE TO THE NAM/GFS MODEL CONTINUITY.

BY LATE MONDAY NIGHT INTO TUESDAY A SOUTHERN BRANCH STORM SYSTEM
FORMS ALONG THE SE COAST AND TAKES A TRACK OFF THE MID ATLANTIC
COAST. THIS SYSTEM GETS CAUGHT UP WITH THE OVERALL LARGE SCALE
AMPLIFICATION OF THE UPPER AIR PATTERN. THERE IS DECENT WARM
ADVECTION WITH COLD AIR DAMMING ACROSS THE INTERIOR. BIGGEST
QUESTION WILL BE IS THERE ENOUGH MOISTURE FOR PRECIP DURING THIS
TIME FRAME. IF PRECIP OVERRUNS THEN COULD SEE FREEZING RAIN/DRIZZLE
ACROSS THE INTERIOR LATE MONDAY INTO TUESDAY MORNING. DURING THE DAY
ON TUESDAY...GOOD AMOUNT OF WARM AIR WILL PUSH SURFACE TEMPS ABOVE
FREEZING ALLOWING FOR ANY PRECIP TO BE MORE OF THE LIQUID VARIETY
AHEAD OF THE CHRISTMAS EVE STORM. HOWEVER GUIDANCE IS ALWAYS TOO
FAST IN SCOURING TEMPS OUT ESP ACROSS THE CT VALLEY SO WE WILL NEED
TO MONITOR THIS CLOSELY...ESP DUE TO LIGHT WINDS AND THE HIGH IN
EASTERN CANADA.

WE COULD ALSO SEE SOME MINOR COASTAL FLOODING CONCERNS ON TUESDAY. SEE
BELOW FOR MORE DETAILS.

WEDNESDAY INTO THURSDAY...HIGH CONFIDENCE IN SYSTEM LOW CONFIDENCE
ON DETAILS.

STRONG ANOMALOUS SYSTEM WILL STRENGTHEN OVER THE GREAT
LAKES...DEVELOPING A POTENTIAL SECONDARY SURFACE LOW JUST WEST OF
SOUTHERN NEW ENGLAND. STILL A LOT OF DETAILS TO WORK OUT AS THIS
SYSTEM IS STILL 5 DAYS AWAY...HOWEVER ENSEMBLES CONTINUE TO SHOW
STRONG AGREEMENT SO HAVE INCREASING CONFIDENCE THAT A POTENT STORM
WILL OCCUR. LATEST 00Z GUIDANCE SHOWS THAT MOST PRECIP WILL BE
LIQUID WITH A DEEP SUBTROPICAL CONNECTION BACK ACROSS THE GULF OF
MEXICO...PW ANOMALIES FORECAST TO RISE BETWEEN +3 TO +4. CURRENT
PWATS ARE PROGGED ABOVE 1.6 INCHES SO HAVE CONTINUED THE CATEGORICAL
POPS. TEMPERATURES WILL BE WELL ABOVE AVERAGE...IN FACT WE MAY BE
CLOSE AT BREAKING RECORD HIGH TEMPS IF TEMPS WARM TO 60F OR ABOVE ON
CHRISTMAS EVE.  AS THE SYSTEM WRAPS UP INTO CANADA...COLD AIR
ADVECTION SHOULD CIRCULATE AROUND AND BEGIN A TRANSITION FROM
SOUTHWEST TO NORTHEAST IN TURNING P-TYPE TO SNOW. HOWEVER LATEST
GUIDANCE DOES SHOW A QUICK MOVING DRY SLOT SO SNOWFALL WILL STRUGGLE
DUE TO LACK OF MOISTURE.

THIS SYSTEM IS QUITE POTENT SO WE WILL NEED TO WATCH FOR POTENTIAL
HAZARDS. CURRENTLY THINK THAT WE COULD POSSIBLE URBAN FLOODING
ISSUES AS MODELS PROGGED WELL OVER 1.5 INCHES OF QPF. LATEST EC EVEN
SHOWS 2.5 INCHES OF QPF IS POSSIBLE. THE GEFS SHOW A MOISTURE FLUX
AT 850 MB BEING 4 TO 5 STANDARD DEVIATIONS AWAY...AND WITH THE
TROPICAL CONNECTION AND STRONG SOUTHERLY FLOW COULD SEE HIGHER
AMOUNTS DUE TO TOPOGRAPHY ENHANCEMENTS. RAIN FALL RECORDS MAY FALL
IF EVERYTHING FALLS INTO PLACE.

ALSO BELIEVE THAT WE MAY SEE SOME WIND ISSUES WITH THIS SYSTEM.
GUIDANCE RIGHT NOW IS SHOWING A 45 TO 55 KT JET AT 925 MB...HOWEVER
IT WILL BE HARD TO BREAK THE INVERSION WITH THE SOUTHERLY FLOW.
RIGHT NOW BELIEVE THAT WIND ADVISORIES MAY BE NEEDED BUT IF THIS
SYSTEM STRENGTHEN EVEN MORE SO A STRONGER JET IS POSSIBLE.

CONTINUED THE MENTIONED OF ISOLATED THUNDER IN THE FORECAST PER PREV
FORECASTER SUGGESTION. BELIEVE IT COULD BE POSSIBLE AS SOUTHERN NEW
ENGLAND WILL BE IN THE WARM SECTOR...WITH THE ANOMALOUS JET AND
SHOWALTERS CLOSE TO ZERO.

FRIDAY...LOW CONFIDENCE.

ONCE UPPER LEVEL LOW MOVES INTO SOUTHERN CANADA...EXPECT A RATHER
FAST UPPER W FLOW IN PLACE. MAY SEE LEFTOVER SNOW SHOWERS BUT TEMPS
WILL FALL BACK CLOSE TO SEASONAL NORMS.

&&

.AVIATION /21Z SATURDAY THROUGH THURSDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH SUNDAY/...

THROUGH 00Z...MODERATE CONFIDENCE. MVFR CIGS WILL CONTINUE TO
OVERSPREAD EASTERN NEW ENGLAND AND EVENTUALLY OVERSPREAD THE INTERIOR
THIS AFTERNOON. SCATTERED SHOWERS ACROSS PORTIONS OF EASTERN
MASSACHUSETTS THIS AFTERNOON. MAINLY SNOW SHOWERS TO THE NORTH AND
WEST OF CAPE COD CANAL...RAIN SHOWERS SOUTH AND EAST. LOCALIZED
IFR CONDITIONS POSSIBLE JUST INLAND FROM THE SOUTHEAST NEW ENGLAND
COAST...WHERE SNOW IS FALLING.

TONIGHT AND SUNDAY...MODERATE CONFIDENCE.  MVFR CONDITIONS DOMINATE
IN LOWER CLOUDS AND SCATTERED SHOWERS. LOCALIZED IFR CONDITIONS
POSSIBLE WITH THE BEST CHANCE IN SNOW SHOWERS. PRECIPITATION
AFFECTS MAINLY EASTERN NEW ENGLAND BUT STILL SOME SCATTERED
ACTIVITY ACROSS WESTERN NEW ENGLAND. MAINLY SNOW SHOWERS TO THE
NORTH AND WEST OF CAPE COD CANAL...RAIN SHOWERS SOUTH AND EAST.

KBOS TERMINAL...MODERATE CONFIDENCE IN TAF. FLURRIES AND SNOW
SHOWERS MAY AFFECT THE TERMINAL BY 21Z.

KBDL TERMINAL...MODERATE CONFIDENCE IN TAF.

OUTLOOK...SUNDAY NIGHT THROUGH WEDNESDAY...

MONDAY INTO TUESDAY...MODERATE CONFIDENCE. EXPECT MOSTLY
VFR...ISOLATED MVFR ALONG THE MASS EAST COASTLINE IN RAIN/SNOW
SHOWERS.

TUESDAY NIGHT INTO WEDNESDAY...MODERATE CONFIDENCE. CONDITIONS WILL
BE DETERIORATING AS HEAVY DOWNPOURS...ISO THUNDER AND GUSTY SOUTHERLY
WINDS MOVE INTO THE REGION BY WEDNESDAY. COULD SEE MVFR TO IFR
CONDITIONS IN CIGS AND VSBYS.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

HIGH CONFIDENCE. HIGH PRESSURE ACROSS QUEBEC WILL RESULT IN
PERSISTENT NORTHEAST WINDS ACROSS THE WATERS THROUGH THE WEEKEND.
WIND GUSTS UP TO 20 KNOTS WITH SEAS BETWEEN 2 AND 4 FEET ARE
EXPECTED FOR MOST WATERS...SO NO HEADLINES PLANNED.

THERE IS A LOW PROBABILITY THAT A BRIEF SURGE OF NORTHEAST WIND
GUSTS NEAR 25 KNOTS WITH MARGINAL 5 FOOT SEAS COULD AFFECT OUR
NORTHERN WATERS LATE TONIGHT INTO SUN MORNING...BUT NOT CONFIDENT
ENOUGH TO ISSUE ANY HEADLINES AT THIS POINT.

OUTLOOK...SUNDAY NIGHT INTO WEDNESDAY...MODERATE TO HIGH
CONFIDENCE.

SUNDAY INTO MONDAY. CONTINUOUS NORTHEAST FLOW WILL KEEP SEAS CHOPPY.
LINGERING NORTHEAST SWELL MAY BUMP SEAS ABOVE 5FT ESP ACROSS THE
NORTHEASTERN WATERS. SCA MAY BE NEEDED...BUT LOWER CONFIDENCE.

TUESDAY INTO WEDNESDAY...NE WINDS WILL INCREASE...GUSTING TO 30 KT
TUE THEN SHIFT TO SE GUSTING TO 30-35 KT WED...HIGHEST ON THE OUTER
WATERS. SEAS BUILD UP TO 7-11 FT BY WED. GALES WILL BE NEEDED.

&&

.TIDES/COASTAL FLOODING...
HIGH ASTRONOMICAL TIDES WILL OCCUR TUESDAY THROUGH THURSDAY. BREAKING
IT DOWN...ON TUESDAY HIGH TIDE AT BOSTON WILL BE 11.6 FT. THERE WILL
BE ONSHORE FLOW DURING THIS HIGH TIDE ALLOWING FOR MINOR SPLASHOVER.
IF WIND GUSTS INCREASE THEN COULD POSSIBLE SEE MINOR COASTAL
FLOODING.

ON WEDNESDAY...WINDS WILL SWITCH TO A MORE SOUTHEASTERLY FLOW DURING
THE DAY AND INCREASE QUICKLY FROM APPROACHING SYSTEM AND DESCENT
PRESSURE FALLS. WEDNESDAY AFTERNOON HIGH TIDE IN BOSTON IS 11.7 FT
AND WITH ANY STRENGTH ON THE EASTERLY WIND FLOW WILL PUSH THE TIDE
OVER. RIGHT NOW BELIEVE MINOR COASTAL FLOODING IS POSSIBLE ALONG THE
EAST COASTLINE. HOWEVER WEDNESDAY EVENING...THE WIND GOES IN A MORE
SOUTHERLY DIRECTION AND HIGH TIDE IN PROVIDENCE WILL BE 5.2 FT. 925
MB LLJ STRENGTHENS TO 50-60 KTS WHICH COULD PUSH A DESCENT SURGE UP
ALONG THE SOUTH COAST DURING THE TIME OF HIGH TIDE. THINKING THAT
MINOR COASTAL FLOODING COULD OCCUR BUT CANNOT RULE OUT MODERATE
ALONG THE SOUTH COAST...ESP IF LLJ STRENGTHENS EVEN MORE.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...DUNTEN/RLG
NEAR TERM...RLG
SHORT TERM...RLG
LONG TERM...DUNTEN
AVIATION...DUNTEN/RLG
MARINE...DUNTEN/RLG
TIDES/COASTAL FLOODING...



000
FXUS61 KBOX 202026
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
326 PM EST SAT DEC 20 2014

.SYNOPSIS...
SCATTERED SNOW/RAIN SHOWERS WILL GRADUALLY OVERSPREAD THE REGION
FROM EAST TO WEST THIS AFTERNOON THROUGH SUN. WEAK LOW PRESSURE
WILL PASS SOUTH OF NEW ENGLAND BRINGING ANOTHER PERIOD OF PRECIP
MON NIGHT AND TUE. A MUCH STRONGER STORM PASSING WEST OF NEW
ENGLAND WILL BRING HEAVY RAINFALL...GUSTY WINDS AND COASTAL
FLOODING CONCERNS TO THE REGION WED INTO WED EVENING. DRY BUT VERY
WINDY CONDITIONS FOLLOW FOR CHRISTMAS DAY INTO FRI.

&&

.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
AN INVERTED TROUGH WILL DEVELOP THIS EVENING IN RESPONSE TO A
SHORTWAVE MOVING ACROSS SOUTHERN NEW ENGLAND.  THIS WILL PROVIDE A
FOCUS FOR RAIN/SNOW SHOWERS ACROSS MUCH OF EASTERN MASSACHUSETTS
BEGINNING THIS AFTERNOON AND CONTINUING THROUGH TONIGHT.  WHILE SNOW
SHOWERS MAY REACH INTO WESTERN NEW ENGLAND TONIGHT...A COASTAL FRONT
WILL DEVELOP...AIDING IN FOCUSING SHOWERS ALONG THE EAST COAST OF
MASSACHUSETTS.

SNOW SHOWERS WILL BECOME MORE WIDESPREAD TONIGHT AS THE LOW LEVELS
MOISTEN UP A BIT MORE. LOOKS LIKE IT WILL LIKELY BE WARM ENOUGH
ACROSS THE CAPE AND SOUTHEASTERN PLYMOUTH COUNTY FOR SHOWERS TO BE
RAIN RATHER THAN SNOW.

OVERALL...EXPECTING 1-2 INCHES OF SNOW AT MOST ACROSS EASTERN
MASSACHUSETTS AND RHODE ISLAND.  THERE ARE SEVERAL POTENTIAL PLACES
WHERE LOCALIZED SLIGHTLY HIGHER AMOUNTS /POSSIBLY UP TO 2-4 INCHES/
ARE POSSIBLE.  LOOKING AT THE HIGH RES MODELS...EITHER ACROSS ESSEX
COUNTY AND CAPE ANN...EASTERN NORFOLK COUNTY INTO NORTHERN PLYMOUTH
COUNTY...OR BOTH. THEN THE HIGHER TERRAIN OF WORCESTER COUNTY AND
PROVIDENCE COUNTY MAY SEE SLIGHTLY HIGHER AMOUNTS GIVEN THE UPSLOPE
COMPONENT OF THE WINDS.

SOME OF THE HIGH RES MODELS HAVE A DECENT CLIP OF QPF INTO ESSEX
COUNTY...WHILE OTHERS HAVE NOTHING IN THE SAME AREA.  FOR NORFOLK
AND PLYMOUTH COUNTY...WE MAY SEE A BIT OF OCEAN ENHANCEMENT THAT
RAISES SNOW AMOUNTS IN THOSE AREAS.  DUE TO THE UNCERTAINTY AND THE
LOCALIZED NATURE OF THE POTENTIAL HIGHER AMOUNTS...AM OPTING NOT TO
ISSUE A WINTER WEATHER ADVISORY. INSTEAD...REISSUED THE SPECIAL
WEATHER STATEMENT FOR SNOW. ANYONE OUT AND ABOUT THIS EVENING IN
EASTERN MASSACHUSETTS WILL WANT TO USE CAUTION AS THERE MAY BE
SLIPPERY PATCHES.

&&

.SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
RAIN/SNOW SHOWERS WILL CONTINUE INTO THE MORNING HOURS...THEN TAPER
OFF AS INVERTED TROUGH PULLS AWAY FROM SOUTHERN NEW ENGLAND AND HIGH
PRESSURE STARTS TO BUILD IN.  MOST LIKELY AREAS FOR CONTINUING
SHOWERS WILL BE ALONG THE IMMEDIATE EAST COAST OF MASSACHUSETTS.

AS THE DAY GOES ON...EXPECT A SLOW DRYING TREND AS HIGH PRESSURE
BUILDS INTO THE REGION.  CLOUDS WILL STICK AROUND WITH TEMPS
GENERALLY IN THE 30S.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
HIGHLIGHTS...

* INVERTED TROUGH WILL BRING RAIN/SNOW SHOWERS TO THE MASS EAST
  COASTLINE MONDAY INTO TUES MORNING.
* WEAK WAVE OF LOW PRESSURE MON NIGHT/TUESDAY COULD BRING WINTRY
  MIX TO INTERIOR
* ANOMALOUS SYSTEM ACROSS THE GREAT LAKES WILL BRING HEAVY
  RAIN...GUSTY WINDS AND COASTAL FLOODING CONCERNS AROUND CHRISTMAS
  EVE

OVERVIEW...

OVERALL 00Z GUIDANCE IS IN AGREEMENT SYNOPTICALLY WITH ISSUES ON
TIMING AND SMALLER SCALE FEATURES. IT REMAINS EVIDENT THAT AN
AMPLIFIED MID-UPPER LEVEL TROUGH AND PCPN FOCUSING LEAD SURFACE
LOW/FRONTAL SYSTEM WILL STEADILY PROGRESS TO THE EAST-CENTRAL U.S.
TUE AS EMBEDDED IMPULSES DIG TO THE LEE OF AN AMPLIFIED ERN
PACIFIC/WEST COAST RIDGE ALOFT. THE SUPPORTING AND INCREASINGLY
NEGATIVE-TILT TROUGH ALOFT WORKS OVER THE ERN US AND OUT THROUGH THE
NERN STATES INTO DAYS 4/5 WED/THU.  MODELS/ENSEMBLES HAVE BEEN
FAIRLY CONSISTENT ON THIS AMPLIFIED PATTERN AND THE MOST RECENT
GEFS/ECMWF ENSEMBLE GUIDANCE SHOW GOOD CORRELATION TO NEXT THURSDAY.

HIGH PRESSURE AND UPPER LEVEL RIDGE OVER THE REGION WILL BEGIN TO
EXIT BY MONDAY. AT THE SURFACE APPEARS ANOTHER INVERTED
TROUGH/ONSHORE FLOW WILL YIELD TO PRECIP ALONG THE MASS COASTLINE ON
MONDAY. ASIDE FROM THIS QUICK MESOSCALE EVENT THE MAIN FOCUS IS ON
THE LONGWAVE DIGGING TROUGH OVER THE CENTRAL CONUS WHICH WILL PUSH A
FEW SHORTWAVES THROUGH THE FLOW. FIRST ONE DEVELOPS A WEAK WAVE
MOVING TOWARDS THE REGION LATE MONDAY INTO TUESDAY. THERE IS STILL
SOME UNCERTAINTY WITH THE LOCATION/STRENGTH OF THIS SYSTEM BUT
APPEARS THAT THERE IS THE POSSIBILITY OF A SNOW/WINTRY MIX IN THE
INTERIOR. AS THIS SYSTEM DEPARTS AN ANOMALOUS LOW OVER THE GREAT
LAKES WILL DEVELOP A SECONDARY LOW JUST WEST OF SOUTHERN NEW ENGLAND
PER ENSEMBLE GUIDANCE. STILL A SOME SPREAD BUT IF THIS DOUBLE LOW
DOES DEVELOP THEN THE RAIN AND WIND ASPECT OF THE SYSTEM
INCREASES...DETAILS BELOW. STILL NEED TO WORK OUT MINOR DETAILS
WITH THIS PARTICULAR SYSTEM BUT WITH 3 TO 4 STANDARD DEVIATIONS
AWAY AND GENERAL MODEL AGREEMENT HAVE HIGH CONFIDENCE THIS SYSTEM
WILL IMPACT SOUTHERN NEW ENGLAND.

DETAILS...

SUNDAY NIGHT INTO TUESDAY...MODERATE CONFIDENCE.

HIGH PRESSURE AND UPPER LEVEL RIDGE WILL BEGIN TO MOVE OFFSHORE AS
DIGGING TROUGH BEGINS TO SET-UP OVER THE CENTRAL CONUS. APPEARS
ANOTHER MESOSCALE INVERTED TROUGH WILL SET UP ON MONDAY AND LAST
INTO EARLY TUESDAY MORNING. GUIDANCE SHOWS THAT RAIN/SNOW SHOWERS
WILL DEVELOP ALONG THE MASS EAST COASTLINE THANKS TO ONSHORE
EASTERLY FLOW. APPEARS THE COLUMN WILL SATURATE PER BUFKIT
SOUNDINGS AND SOUTHERLY FLOW ALOFT. BOTH THE NAM AND GFS SHOW QPF
MAKING IT ONSHORE DURING THIS TIME FRAME. HOWEVER THE EC IS
SLIGHTLY SLOWER AND KEEP THE BULK OF THE PRECIP JUST OFFSHORE. ADD
A CHANCE OF POPS DUE TO THE NAM/GFS MODEL CONTINUITY.

BY LATE MONDAY NIGHT INTO TUESDAY A SOUTHERN BRANCH STORM SYSTEM
FORMS ALONG THE SE COAST AND TAKES A TRACK OFF THE MID ATLANTIC
COAST. THIS SYSTEM GETS CAUGHT UP WITH THE OVERALL LARGE SCALE
AMPLIFICATION OF THE UPPER AIR PATTERN. THERE IS DECENT WARM
ADVECTION WITH COLD AIR DAMMING ACROSS THE INTERIOR. BIGGEST
QUESTION WILL BE IS THERE ENOUGH MOISTURE FOR PRECIP DURING THIS
TIME FRAME. IF PRECIP OVERRUNS THEN COULD SEE FREEZING RAIN/DRIZZLE
ACROSS THE INTERIOR LATE MONDAY INTO TUESDAY MORNING. DURING THE DAY
ON TUESDAY...GOOD AMOUNT OF WARM AIR WILL PUSH SURFACE TEMPS ABOVE
FREEZING ALLOWING FOR ANY PRECIP TO BE MORE OF THE LIQUID VARIETY
AHEAD OF THE CHRISTMAS EVE STORM. HOWEVER GUIDANCE IS ALWAYS TOO
FAST IN SCOURING TEMPS OUT ESP ACROSS THE CT VALLEY SO WE WILL NEED
TO MONITOR THIS CLOSELY...ESP DUE TO LIGHT WINDS AND THE HIGH IN
EASTERN CANADA.

WE COULD ALSO SEE SOME MINOR COASTAL FLOODING CONCERNS ON TUESDAY. SEE
BELOW FOR MORE DETAILS.

WEDNESDAY INTO THURSDAY...HIGH CONFIDENCE IN SYSTEM LOW CONFIDENCE
ON DETAILS.

STRONG ANOMALOUS SYSTEM WILL STRENGTHEN OVER THE GREAT
LAKES...DEVELOPING A POTENTIAL SECONDARY SURFACE LOW JUST WEST OF
SOUTHERN NEW ENGLAND. STILL A LOT OF DETAILS TO WORK OUT AS THIS
SYSTEM IS STILL 5 DAYS AWAY...HOWEVER ENSEMBLES CONTINUE TO SHOW
STRONG AGREEMENT SO HAVE INCREASING CONFIDENCE THAT A POTENT STORM
WILL OCCUR. LATEST 00Z GUIDANCE SHOWS THAT MOST PRECIP WILL BE
LIQUID WITH A DEEP SUBTROPICAL CONNECTION BACK ACROSS THE GULF OF
MEXICO...PW ANOMALIES FORECAST TO RISE BETWEEN +3 TO +4. CURRENT
PWATS ARE PROGGED ABOVE 1.6 INCHES SO HAVE CONTINUED THE CATEGORICAL
POPS. TEMPERATURES WILL BE WELL ABOVE AVERAGE...IN FACT WE MAY BE
CLOSE AT BREAKING RECORD HIGH TEMPS IF TEMPS WARM TO 60F OR ABOVE ON
CHRISTMAS EVE.  AS THE SYSTEM WRAPS UP INTO CANADA...COLD AIR
ADVECTION SHOULD CIRCULATE AROUND AND BEGIN A TRANSITION FROM
SOUTHWEST TO NORTHEAST IN TURNING P-TYPE TO SNOW. HOWEVER LATEST
GUIDANCE DOES SHOW A QUICK MOVING DRY SLOT SO SNOWFALL WILL STRUGGLE
DUE TO LACK OF MOISTURE.

THIS SYSTEM IS QUITE POTENT SO WE WILL NEED TO WATCH FOR POTENTIAL
HAZARDS. CURRENTLY THINK THAT WE COULD POSSIBLE URBAN FLOODING
ISSUES AS MODELS PROGGED WELL OVER 1.5 INCHES OF QPF. LATEST EC EVEN
SHOWS 2.5 INCHES OF QPF IS POSSIBLE. THE GEFS SHOW A MOISTURE FLUX
AT 850 MB BEING 4 TO 5 STANDARD DEVIATIONS AWAY...AND WITH THE
TROPICAL CONNECTION AND STRONG SOUTHERLY FLOW COULD SEE HIGHER
AMOUNTS DUE TO TOPOGRAPHY ENHANCEMENTS. RAIN FALL RECORDS MAY FALL
IF EVERYTHING FALLS INTO PLACE.

ALSO BELIEVE THAT WE MAY SEE SOME WIND ISSUES WITH THIS SYSTEM.
GUIDANCE RIGHT NOW IS SHOWING A 45 TO 55 KT JET AT 925 MB...HOWEVER
IT WILL BE HARD TO BREAK THE INVERSION WITH THE SOUTHERLY FLOW.
RIGHT NOW BELIEVE THAT WIND ADVISORIES MAY BE NEEDED BUT IF THIS
SYSTEM STRENGTHEN EVEN MORE SO A STRONGER JET IS POSSIBLE.

CONTINUED THE MENTIONED OF ISOLATED THUNDER IN THE FORECAST PER PREV
FORECASTER SUGGESTION. BELIEVE IT COULD BE POSSIBLE AS SOUTHERN NEW
ENGLAND WILL BE IN THE WARM SECTOR...WITH THE ANOMALOUS JET AND
SHOWALTERS CLOSE TO ZERO.

FRIDAY...LOW CONFIDENCE.

ONCE UPPER LEVEL LOW MOVES INTO SOUTHERN CANADA...EXPECT A RATHER
FAST UPPER W FLOW IN PLACE. MAY SEE LEFTOVER SNOW SHOWERS BUT TEMPS
WILL FALL BACK CLOSE TO SEASONAL NORMS.

&&

.AVIATION /21Z SATURDAY THROUGH THURSDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH SUNDAY/...

THROUGH 00Z...MODERATE CONFIDENCE. MVFR CIGS WILL CONTINUE TO
OVERSPREAD EASTERN NEW ENGLAND AND EVENTUALLY OVERSPREAD THE INTERIOR
THIS AFTERNOON. SCATTERED SHOWERS ACROSS PORTIONS OF EASTERN
MASSACHUSETTS THIS AFTERNOON. MAINLY SNOW SHOWERS TO THE NORTH AND
WEST OF CAPE COD CANAL...RAIN SHOWERS SOUTH AND EAST. LOCALIZED
IFR CONDITIONS POSSIBLE JUST INLAND FROM THE SOUTHEAST NEW ENGLAND
COAST...WHERE SNOW IS FALLING.

TONIGHT AND SUNDAY...MODERATE CONFIDENCE.  MVFR CONDITIONS DOMINATE
IN LOWER CLOUDS AND SCATTERED SHOWERS. LOCALIZED IFR CONDITIONS
POSSIBLE WITH THE BEST CHANCE IN SNOW SHOWERS. PRECIPITATION
AFFECTS MAINLY EASTERN NEW ENGLAND BUT STILL SOME SCATTERED
ACTIVITY ACROSS WESTERN NEW ENGLAND. MAINLY SNOW SHOWERS TO THE
NORTH AND WEST OF CAPE COD CANAL...RAIN SHOWERS SOUTH AND EAST.

KBOS TERMINAL...MODERATE CONFIDENCE IN TAF. FLURRIES AND SNOW
SHOWERS MAY AFFECT THE TERMINAL BY 21Z.

KBDL TERMINAL...MODERATE CONFIDENCE IN TAF.

OUTLOOK...SUNDAY NIGHT THROUGH WEDNESDAY...

MONDAY INTO TUESDAY...MODERATE CONFIDENCE. EXPECT MOSTLY
VFR...ISOLATED MVFR ALONG THE MASS EAST COASTLINE IN RAIN/SNOW
SHOWERS.

TUESDAY NIGHT INTO WEDNESDAY...MODERATE CONFIDENCE. CONDITIONS WILL
BE DETERIORATING AS HEAVY DOWNPOURS...ISO THUNDER AND GUSTY SOUTHERLY
WINDS MOVE INTO THE REGION BY WEDNESDAY. COULD SEE MVFR TO IFR
CONDITIONS IN CIGS AND VSBYS.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

HIGH CONFIDENCE. HIGH PRESSURE ACROSS QUEBEC WILL RESULT IN
PERSISTENT NORTHEAST WINDS ACROSS THE WATERS THROUGH THE WEEKEND.
WIND GUSTS UP TO 20 KNOTS WITH SEAS BETWEEN 2 AND 4 FEET ARE
EXPECTED FOR MOST WATERS...SO NO HEADLINES PLANNED.

THERE IS A LOW PROBABILITY THAT A BRIEF SURGE OF NORTHEAST WIND
GUSTS NEAR 25 KNOTS WITH MARGINAL 5 FOOT SEAS COULD AFFECT OUR
NORTHERN WATERS LATE TONIGHT INTO SUN MORNING...BUT NOT CONFIDENT
ENOUGH TO ISSUE ANY HEADLINES AT THIS POINT.

OUTLOOK...SUNDAY NIGHT INTO WEDNESDAY...MODERATE TO HIGH
CONFIDENCE.

SUNDAY INTO MONDAY. CONTINUOUS NORTHEAST FLOW WILL KEEP SEAS CHOPPY.
LINGERING NORTHEAST SWELL MAY BUMP SEAS ABOVE 5FT ESP ACROSS THE
NORTHEASTERN WATERS. SCA MAY BE NEEDED...BUT LOWER CONFIDENCE.

TUESDAY INTO WEDNESDAY...NE WINDS WILL INCREASE...GUSTING TO 30 KT
TUE THEN SHIFT TO SE GUSTING TO 30-35 KT WED...HIGHEST ON THE OUTER
WATERS. SEAS BUILD UP TO 7-11 FT BY WED. GALES WILL BE NEEDED.

&&

.TIDES/COASTAL FLOODING...
HIGH ASTRONOMICAL TIDES WILL OCCUR TUESDAY THROUGH THURSDAY. BREAKING
IT DOWN...ON TUESDAY HIGH TIDE AT BOSTON WILL BE 11.6 FT. THERE WILL
BE ONSHORE FLOW DURING THIS HIGH TIDE ALLOWING FOR MINOR SPLASHOVER.
IF WIND GUSTS INCREASE THEN COULD POSSIBLE SEE MINOR COASTAL
FLOODING.

ON WEDNESDAY...WINDS WILL SWITCH TO A MORE SOUTHEASTERLY FLOW DURING
THE DAY AND INCREASE QUICKLY FROM APPROACHING SYSTEM AND DESCENT
PRESSURE FALLS. WEDNESDAY AFTERNOON HIGH TIDE IN BOSTON IS 11.7 FT
AND WITH ANY STRENGTH ON THE EASTERLY WIND FLOW WILL PUSH THE TIDE
OVER. RIGHT NOW BELIEVE MINOR COASTAL FLOODING IS POSSIBLE ALONG THE
EAST COASTLINE. HOWEVER WEDNESDAY EVENING...THE WIND GOES IN A MORE
SOUTHERLY DIRECTION AND HIGH TIDE IN PROVIDENCE WILL BE 5.2 FT. 925
MB LLJ STRENGTHENS TO 50-60 KTS WHICH COULD PUSH A DESCENT SURGE UP
ALONG THE SOUTH COAST DURING THE TIME OF HIGH TIDE. THINKING THAT
MINOR COASTAL FLOODING COULD OCCUR BUT CANNOT RULE OUT MODERATE
ALONG THE SOUTH COAST...ESP IF LLJ STRENGTHENS EVEN MORE.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...DUNTEN/RLG
NEAR TERM...RLG
SHORT TERM...RLG
LONG TERM...DUNTEN
AVIATION...DUNTEN/RLG
MARINE...DUNTEN/RLG
TIDES/COASTAL FLOODING...



000
FXUS61 KBOX 202026
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
326 PM EST SAT DEC 20 2014

.SYNOPSIS...
SCATTERED SNOW/RAIN SHOWERS WILL GRADUALLY OVERSPREAD THE REGION
FROM EAST TO WEST THIS AFTERNOON THROUGH SUN. WEAK LOW PRESSURE
WILL PASS SOUTH OF NEW ENGLAND BRINGING ANOTHER PERIOD OF PRECIP
MON NIGHT AND TUE. A MUCH STRONGER STORM PASSING WEST OF NEW
ENGLAND WILL BRING HEAVY RAINFALL...GUSTY WINDS AND COASTAL
FLOODING CONCERNS TO THE REGION WED INTO WED EVENING. DRY BUT VERY
WINDY CONDITIONS FOLLOW FOR CHRISTMAS DAY INTO FRI.

&&

.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
AN INVERTED TROUGH WILL DEVELOP THIS EVENING IN RESPONSE TO A
SHORTWAVE MOVING ACROSS SOUTHERN NEW ENGLAND.  THIS WILL PROVIDE A
FOCUS FOR RAIN/SNOW SHOWERS ACROSS MUCH OF EASTERN MASSACHUSETTS
BEGINNING THIS AFTERNOON AND CONTINUING THROUGH TONIGHT.  WHILE SNOW
SHOWERS MAY REACH INTO WESTERN NEW ENGLAND TONIGHT...A COASTAL FRONT
WILL DEVELOP...AIDING IN FOCUSING SHOWERS ALONG THE EAST COAST OF
MASSACHUSETTS.

SNOW SHOWERS WILL BECOME MORE WIDESPREAD TONIGHT AS THE LOW LEVELS
MOISTEN UP A BIT MORE. LOOKS LIKE IT WILL LIKELY BE WARM ENOUGH
ACROSS THE CAPE AND SOUTHEASTERN PLYMOUTH COUNTY FOR SHOWERS TO BE
RAIN RATHER THAN SNOW.

OVERALL...EXPECTING 1-2 INCHES OF SNOW AT MOST ACROSS EASTERN
MASSACHUSETTS AND RHODE ISLAND.  THERE ARE SEVERAL POTENTIAL PLACES
WHERE LOCALIZED SLIGHTLY HIGHER AMOUNTS /POSSIBLY UP TO 2-4 INCHES/
ARE POSSIBLE.  LOOKING AT THE HIGH RES MODELS...EITHER ACROSS ESSEX
COUNTY AND CAPE ANN...EASTERN NORFOLK COUNTY INTO NORTHERN PLYMOUTH
COUNTY...OR BOTH. THEN THE HIGHER TERRAIN OF WORCESTER COUNTY AND
PROVIDENCE COUNTY MAY SEE SLIGHTLY HIGHER AMOUNTS GIVEN THE UPSLOPE
COMPONENT OF THE WINDS.

SOME OF THE HIGH RES MODELS HAVE A DECENT CLIP OF QPF INTO ESSEX
COUNTY...WHILE OTHERS HAVE NOTHING IN THE SAME AREA.  FOR NORFOLK
AND PLYMOUTH COUNTY...WE MAY SEE A BIT OF OCEAN ENHANCEMENT THAT
RAISES SNOW AMOUNTS IN THOSE AREAS.  DUE TO THE UNCERTAINTY AND THE
LOCALIZED NATURE OF THE POTENTIAL HIGHER AMOUNTS...AM OPTING NOT TO
ISSUE A WINTER WEATHER ADVISORY. INSTEAD...REISSUED THE SPECIAL
WEATHER STATEMENT FOR SNOW. ANYONE OUT AND ABOUT THIS EVENING IN
EASTERN MASSACHUSETTS WILL WANT TO USE CAUTION AS THERE MAY BE
SLIPPERY PATCHES.

&&

.SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
RAIN/SNOW SHOWERS WILL CONTINUE INTO THE MORNING HOURS...THEN TAPER
OFF AS INVERTED TROUGH PULLS AWAY FROM SOUTHERN NEW ENGLAND AND HIGH
PRESSURE STARTS TO BUILD IN.  MOST LIKELY AREAS FOR CONTINUING
SHOWERS WILL BE ALONG THE IMMEDIATE EAST COAST OF MASSACHUSETTS.

AS THE DAY GOES ON...EXPECT A SLOW DRYING TREND AS HIGH PRESSURE
BUILDS INTO THE REGION.  CLOUDS WILL STICK AROUND WITH TEMPS
GENERALLY IN THE 30S.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
HIGHLIGHTS...

* INVERTED TROUGH WILL BRING RAIN/SNOW SHOWERS TO THE MASS EAST
  COASTLINE MONDAY INTO TUES MORNING.
* WEAK WAVE OF LOW PRESSURE MON NIGHT/TUESDAY COULD BRING WINTRY
  MIX TO INTERIOR
* ANOMALOUS SYSTEM ACROSS THE GREAT LAKES WILL BRING HEAVY
  RAIN...GUSTY WINDS AND COASTAL FLOODING CONCERNS AROUND CHRISTMAS
  EVE

OVERVIEW...

OVERALL 00Z GUIDANCE IS IN AGREEMENT SYNOPTICALLY WITH ISSUES ON
TIMING AND SMALLER SCALE FEATURES. IT REMAINS EVIDENT THAT AN
AMPLIFIED MID-UPPER LEVEL TROUGH AND PCPN FOCUSING LEAD SURFACE
LOW/FRONTAL SYSTEM WILL STEADILY PROGRESS TO THE EAST-CENTRAL U.S.
TUE AS EMBEDDED IMPULSES DIG TO THE LEE OF AN AMPLIFIED ERN
PACIFIC/WEST COAST RIDGE ALOFT. THE SUPPORTING AND INCREASINGLY
NEGATIVE-TILT TROUGH ALOFT WORKS OVER THE ERN US AND OUT THROUGH THE
NERN STATES INTO DAYS 4/5 WED/THU.  MODELS/ENSEMBLES HAVE BEEN
FAIRLY CONSISTENT ON THIS AMPLIFIED PATTERN AND THE MOST RECENT
GEFS/ECMWF ENSEMBLE GUIDANCE SHOW GOOD CORRELATION TO NEXT THURSDAY.

HIGH PRESSURE AND UPPER LEVEL RIDGE OVER THE REGION WILL BEGIN TO
EXIT BY MONDAY. AT THE SURFACE APPEARS ANOTHER INVERTED
TROUGH/ONSHORE FLOW WILL YIELD TO PRECIP ALONG THE MASS COASTLINE ON
MONDAY. ASIDE FROM THIS QUICK MESOSCALE EVENT THE MAIN FOCUS IS ON
THE LONGWAVE DIGGING TROUGH OVER THE CENTRAL CONUS WHICH WILL PUSH A
FEW SHORTWAVES THROUGH THE FLOW. FIRST ONE DEVELOPS A WEAK WAVE
MOVING TOWARDS THE REGION LATE MONDAY INTO TUESDAY. THERE IS STILL
SOME UNCERTAINTY WITH THE LOCATION/STRENGTH OF THIS SYSTEM BUT
APPEARS THAT THERE IS THE POSSIBILITY OF A SNOW/WINTRY MIX IN THE
INTERIOR. AS THIS SYSTEM DEPARTS AN ANOMALOUS LOW OVER THE GREAT
LAKES WILL DEVELOP A SECONDARY LOW JUST WEST OF SOUTHERN NEW ENGLAND
PER ENSEMBLE GUIDANCE. STILL A SOME SPREAD BUT IF THIS DOUBLE LOW
DOES DEVELOP THEN THE RAIN AND WIND ASPECT OF THE SYSTEM
INCREASES...DETAILS BELOW. STILL NEED TO WORK OUT MINOR DETAILS
WITH THIS PARTICULAR SYSTEM BUT WITH 3 TO 4 STANDARD DEVIATIONS
AWAY AND GENERAL MODEL AGREEMENT HAVE HIGH CONFIDENCE THIS SYSTEM
WILL IMPACT SOUTHERN NEW ENGLAND.

DETAILS...

SUNDAY NIGHT INTO TUESDAY...MODERATE CONFIDENCE.

HIGH PRESSURE AND UPPER LEVEL RIDGE WILL BEGIN TO MOVE OFFSHORE AS
DIGGING TROUGH BEGINS TO SET-UP OVER THE CENTRAL CONUS. APPEARS
ANOTHER MESOSCALE INVERTED TROUGH WILL SET UP ON MONDAY AND LAST
INTO EARLY TUESDAY MORNING. GUIDANCE SHOWS THAT RAIN/SNOW SHOWERS
WILL DEVELOP ALONG THE MASS EAST COASTLINE THANKS TO ONSHORE
EASTERLY FLOW. APPEARS THE COLUMN WILL SATURATE PER BUFKIT
SOUNDINGS AND SOUTHERLY FLOW ALOFT. BOTH THE NAM AND GFS SHOW QPF
MAKING IT ONSHORE DURING THIS TIME FRAME. HOWEVER THE EC IS
SLIGHTLY SLOWER AND KEEP THE BULK OF THE PRECIP JUST OFFSHORE. ADD
A CHANCE OF POPS DUE TO THE NAM/GFS MODEL CONTINUITY.

BY LATE MONDAY NIGHT INTO TUESDAY A SOUTHERN BRANCH STORM SYSTEM
FORMS ALONG THE SE COAST AND TAKES A TRACK OFF THE MID ATLANTIC
COAST. THIS SYSTEM GETS CAUGHT UP WITH THE OVERALL LARGE SCALE
AMPLIFICATION OF THE UPPER AIR PATTERN. THERE IS DECENT WARM
ADVECTION WITH COLD AIR DAMMING ACROSS THE INTERIOR. BIGGEST
QUESTION WILL BE IS THERE ENOUGH MOISTURE FOR PRECIP DURING THIS
TIME FRAME. IF PRECIP OVERRUNS THEN COULD SEE FREEZING RAIN/DRIZZLE
ACROSS THE INTERIOR LATE MONDAY INTO TUESDAY MORNING. DURING THE DAY
ON TUESDAY...GOOD AMOUNT OF WARM AIR WILL PUSH SURFACE TEMPS ABOVE
FREEZING ALLOWING FOR ANY PRECIP TO BE MORE OF THE LIQUID VARIETY
AHEAD OF THE CHRISTMAS EVE STORM. HOWEVER GUIDANCE IS ALWAYS TOO
FAST IN SCOURING TEMPS OUT ESP ACROSS THE CT VALLEY SO WE WILL NEED
TO MONITOR THIS CLOSELY...ESP DUE TO LIGHT WINDS AND THE HIGH IN
EASTERN CANADA.

WE COULD ALSO SEE SOME MINOR COASTAL FLOODING CONCERNS ON TUESDAY. SEE
BELOW FOR MORE DETAILS.

WEDNESDAY INTO THURSDAY...HIGH CONFIDENCE IN SYSTEM LOW CONFIDENCE
ON DETAILS.

STRONG ANOMALOUS SYSTEM WILL STRENGTHEN OVER THE GREAT
LAKES...DEVELOPING A POTENTIAL SECONDARY SURFACE LOW JUST WEST OF
SOUTHERN NEW ENGLAND. STILL A LOT OF DETAILS TO WORK OUT AS THIS
SYSTEM IS STILL 5 DAYS AWAY...HOWEVER ENSEMBLES CONTINUE TO SHOW
STRONG AGREEMENT SO HAVE INCREASING CONFIDENCE THAT A POTENT STORM
WILL OCCUR. LATEST 00Z GUIDANCE SHOWS THAT MOST PRECIP WILL BE
LIQUID WITH A DEEP SUBTROPICAL CONNECTION BACK ACROSS THE GULF OF
MEXICO...PW ANOMALIES FORECAST TO RISE BETWEEN +3 TO +4. CURRENT
PWATS ARE PROGGED ABOVE 1.6 INCHES SO HAVE CONTINUED THE CATEGORICAL
POPS. TEMPERATURES WILL BE WELL ABOVE AVERAGE...IN FACT WE MAY BE
CLOSE AT BREAKING RECORD HIGH TEMPS IF TEMPS WARM TO 60F OR ABOVE ON
CHRISTMAS EVE.  AS THE SYSTEM WRAPS UP INTO CANADA...COLD AIR
ADVECTION SHOULD CIRCULATE AROUND AND BEGIN A TRANSITION FROM
SOUTHWEST TO NORTHEAST IN TURNING P-TYPE TO SNOW. HOWEVER LATEST
GUIDANCE DOES SHOW A QUICK MOVING DRY SLOT SO SNOWFALL WILL STRUGGLE
DUE TO LACK OF MOISTURE.

THIS SYSTEM IS QUITE POTENT SO WE WILL NEED TO WATCH FOR POTENTIAL
HAZARDS. CURRENTLY THINK THAT WE COULD POSSIBLE URBAN FLOODING
ISSUES AS MODELS PROGGED WELL OVER 1.5 INCHES OF QPF. LATEST EC EVEN
SHOWS 2.5 INCHES OF QPF IS POSSIBLE. THE GEFS SHOW A MOISTURE FLUX
AT 850 MB BEING 4 TO 5 STANDARD DEVIATIONS AWAY...AND WITH THE
TROPICAL CONNECTION AND STRONG SOUTHERLY FLOW COULD SEE HIGHER
AMOUNTS DUE TO TOPOGRAPHY ENHANCEMENTS. RAIN FALL RECORDS MAY FALL
IF EVERYTHING FALLS INTO PLACE.

ALSO BELIEVE THAT WE MAY SEE SOME WIND ISSUES WITH THIS SYSTEM.
GUIDANCE RIGHT NOW IS SHOWING A 45 TO 55 KT JET AT 925 MB...HOWEVER
IT WILL BE HARD TO BREAK THE INVERSION WITH THE SOUTHERLY FLOW.
RIGHT NOW BELIEVE THAT WIND ADVISORIES MAY BE NEEDED BUT IF THIS
SYSTEM STRENGTHEN EVEN MORE SO A STRONGER JET IS POSSIBLE.

CONTINUED THE MENTIONED OF ISOLATED THUNDER IN THE FORECAST PER PREV
FORECASTER SUGGESTION. BELIEVE IT COULD BE POSSIBLE AS SOUTHERN NEW
ENGLAND WILL BE IN THE WARM SECTOR...WITH THE ANOMALOUS JET AND
SHOWALTERS CLOSE TO ZERO.

FRIDAY...LOW CONFIDENCE.

ONCE UPPER LEVEL LOW MOVES INTO SOUTHERN CANADA...EXPECT A RATHER
FAST UPPER W FLOW IN PLACE. MAY SEE LEFTOVER SNOW SHOWERS BUT TEMPS
WILL FALL BACK CLOSE TO SEASONAL NORMS.

&&

.AVIATION /21Z SATURDAY THROUGH THURSDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH SUNDAY/...

THROUGH 00Z...MODERATE CONFIDENCE. MVFR CIGS WILL CONTINUE TO
OVERSPREAD EASTERN NEW ENGLAND AND EVENTUALLY OVERSPREAD THE INTERIOR
THIS AFTERNOON. SCATTERED SHOWERS ACROSS PORTIONS OF EASTERN
MASSACHUSETTS THIS AFTERNOON. MAINLY SNOW SHOWERS TO THE NORTH AND
WEST OF CAPE COD CANAL...RAIN SHOWERS SOUTH AND EAST. LOCALIZED
IFR CONDITIONS POSSIBLE JUST INLAND FROM THE SOUTHEAST NEW ENGLAND
COAST...WHERE SNOW IS FALLING.

TONIGHT AND SUNDAY...MODERATE CONFIDENCE.  MVFR CONDITIONS DOMINATE
IN LOWER CLOUDS AND SCATTERED SHOWERS. LOCALIZED IFR CONDITIONS
POSSIBLE WITH THE BEST CHANCE IN SNOW SHOWERS. PRECIPITATION
AFFECTS MAINLY EASTERN NEW ENGLAND BUT STILL SOME SCATTERED
ACTIVITY ACROSS WESTERN NEW ENGLAND. MAINLY SNOW SHOWERS TO THE
NORTH AND WEST OF CAPE COD CANAL...RAIN SHOWERS SOUTH AND EAST.

KBOS TERMINAL...MODERATE CONFIDENCE IN TAF. FLURRIES AND SNOW
SHOWERS MAY AFFECT THE TERMINAL BY 21Z.

KBDL TERMINAL...MODERATE CONFIDENCE IN TAF.

OUTLOOK...SUNDAY NIGHT THROUGH WEDNESDAY...

MONDAY INTO TUESDAY...MODERATE CONFIDENCE. EXPECT MOSTLY
VFR...ISOLATED MVFR ALONG THE MASS EAST COASTLINE IN RAIN/SNOW
SHOWERS.

TUESDAY NIGHT INTO WEDNESDAY...MODERATE CONFIDENCE. CONDITIONS WILL
BE DETERIORATING AS HEAVY DOWNPOURS...ISO THUNDER AND GUSTY SOUTHERLY
WINDS MOVE INTO THE REGION BY WEDNESDAY. COULD SEE MVFR TO IFR
CONDITIONS IN CIGS AND VSBYS.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

HIGH CONFIDENCE. HIGH PRESSURE ACROSS QUEBEC WILL RESULT IN
PERSISTENT NORTHEAST WINDS ACROSS THE WATERS THROUGH THE WEEKEND.
WIND GUSTS UP TO 20 KNOTS WITH SEAS BETWEEN 2 AND 4 FEET ARE
EXPECTED FOR MOST WATERS...SO NO HEADLINES PLANNED.

THERE IS A LOW PROBABILITY THAT A BRIEF SURGE OF NORTHEAST WIND
GUSTS NEAR 25 KNOTS WITH MARGINAL 5 FOOT SEAS COULD AFFECT OUR
NORTHERN WATERS LATE TONIGHT INTO SUN MORNING...BUT NOT CONFIDENT
ENOUGH TO ISSUE ANY HEADLINES AT THIS POINT.

OUTLOOK...SUNDAY NIGHT INTO WEDNESDAY...MODERATE TO HIGH
CONFIDENCE.

SUNDAY INTO MONDAY. CONTINUOUS NORTHEAST FLOW WILL KEEP SEAS CHOPPY.
LINGERING NORTHEAST SWELL MAY BUMP SEAS ABOVE 5FT ESP ACROSS THE
NORTHEASTERN WATERS. SCA MAY BE NEEDED...BUT LOWER CONFIDENCE.

TUESDAY INTO WEDNESDAY...NE WINDS WILL INCREASE...GUSTING TO 30 KT
TUE THEN SHIFT TO SE GUSTING TO 30-35 KT WED...HIGHEST ON THE OUTER
WATERS. SEAS BUILD UP TO 7-11 FT BY WED. GALES WILL BE NEEDED.

&&

.TIDES/COASTAL FLOODING...
HIGH ASTRONOMICAL TIDES WILL OCCUR TUESDAY THROUGH THURSDAY. BREAKING
IT DOWN...ON TUESDAY HIGH TIDE AT BOSTON WILL BE 11.6 FT. THERE WILL
BE ONSHORE FLOW DURING THIS HIGH TIDE ALLOWING FOR MINOR SPLASHOVER.
IF WIND GUSTS INCREASE THEN COULD POSSIBLE SEE MINOR COASTAL
FLOODING.

ON WEDNESDAY...WINDS WILL SWITCH TO A MORE SOUTHEASTERLY FLOW DURING
THE DAY AND INCREASE QUICKLY FROM APPROACHING SYSTEM AND DESCENT
PRESSURE FALLS. WEDNESDAY AFTERNOON HIGH TIDE IN BOSTON IS 11.7 FT
AND WITH ANY STRENGTH ON THE EASTERLY WIND FLOW WILL PUSH THE TIDE
OVER. RIGHT NOW BELIEVE MINOR COASTAL FLOODING IS POSSIBLE ALONG THE
EAST COASTLINE. HOWEVER WEDNESDAY EVENING...THE WIND GOES IN A MORE
SOUTHERLY DIRECTION AND HIGH TIDE IN PROVIDENCE WILL BE 5.2 FT. 925
MB LLJ STRENGTHENS TO 50-60 KTS WHICH COULD PUSH A DESCENT SURGE UP
ALONG THE SOUTH COAST DURING THE TIME OF HIGH TIDE. THINKING THAT
MINOR COASTAL FLOODING COULD OCCUR BUT CANNOT RULE OUT MODERATE
ALONG THE SOUTH COAST...ESP IF LLJ STRENGTHENS EVEN MORE.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...DUNTEN/RLG
NEAR TERM...RLG
SHORT TERM...RLG
LONG TERM...DUNTEN
AVIATION...DUNTEN/RLG
MARINE...DUNTEN/RLG
TIDES/COASTAL FLOODING...



000
FXUS61 KBOX 202026
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
326 PM EST SAT DEC 20 2014

.SYNOPSIS...
SCATTERED SNOW/RAIN SHOWERS WILL GRADUALLY OVERSPREAD THE REGION
FROM EAST TO WEST THIS AFTERNOON THROUGH SUN. WEAK LOW PRESSURE
WILL PASS SOUTH OF NEW ENGLAND BRINGING ANOTHER PERIOD OF PRECIP
MON NIGHT AND TUE. A MUCH STRONGER STORM PASSING WEST OF NEW
ENGLAND WILL BRING HEAVY RAINFALL...GUSTY WINDS AND COASTAL
FLOODING CONCERNS TO THE REGION WED INTO WED EVENING. DRY BUT VERY
WINDY CONDITIONS FOLLOW FOR CHRISTMAS DAY INTO FRI.

&&

.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
AN INVERTED TROUGH WILL DEVELOP THIS EVENING IN RESPONSE TO A
SHORTWAVE MOVING ACROSS SOUTHERN NEW ENGLAND.  THIS WILL PROVIDE A
FOCUS FOR RAIN/SNOW SHOWERS ACROSS MUCH OF EASTERN MASSACHUSETTS
BEGINNING THIS AFTERNOON AND CONTINUING THROUGH TONIGHT.  WHILE SNOW
SHOWERS MAY REACH INTO WESTERN NEW ENGLAND TONIGHT...A COASTAL FRONT
WILL DEVELOP...AIDING IN FOCUSING SHOWERS ALONG THE EAST COAST OF
MASSACHUSETTS.

SNOW SHOWERS WILL BECOME MORE WIDESPREAD TONIGHT AS THE LOW LEVELS
MOISTEN UP A BIT MORE. LOOKS LIKE IT WILL LIKELY BE WARM ENOUGH
ACROSS THE CAPE AND SOUTHEASTERN PLYMOUTH COUNTY FOR SHOWERS TO BE
RAIN RATHER THAN SNOW.

OVERALL...EXPECTING 1-2 INCHES OF SNOW AT MOST ACROSS EASTERN
MASSACHUSETTS AND RHODE ISLAND.  THERE ARE SEVERAL POTENTIAL PLACES
WHERE LOCALIZED SLIGHTLY HIGHER AMOUNTS /POSSIBLY UP TO 2-4 INCHES/
ARE POSSIBLE.  LOOKING AT THE HIGH RES MODELS...EITHER ACROSS ESSEX
COUNTY AND CAPE ANN...EASTERN NORFOLK COUNTY INTO NORTHERN PLYMOUTH
COUNTY...OR BOTH. THEN THE HIGHER TERRAIN OF WORCESTER COUNTY AND
PROVIDENCE COUNTY MAY SEE SLIGHTLY HIGHER AMOUNTS GIVEN THE UPSLOPE
COMPONENT OF THE WINDS.

SOME OF THE HIGH RES MODELS HAVE A DECENT CLIP OF QPF INTO ESSEX
COUNTY...WHILE OTHERS HAVE NOTHING IN THE SAME AREA.  FOR NORFOLK
AND PLYMOUTH COUNTY...WE MAY SEE A BIT OF OCEAN ENHANCEMENT THAT
RAISES SNOW AMOUNTS IN THOSE AREAS.  DUE TO THE UNCERTAINTY AND THE
LOCALIZED NATURE OF THE POTENTIAL HIGHER AMOUNTS...AM OPTING NOT TO
ISSUE A WINTER WEATHER ADVISORY. INSTEAD...REISSUED THE SPECIAL
WEATHER STATEMENT FOR SNOW. ANYONE OUT AND ABOUT THIS EVENING IN
EASTERN MASSACHUSETTS WILL WANT TO USE CAUTION AS THERE MAY BE
SLIPPERY PATCHES.

&&

.SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
RAIN/SNOW SHOWERS WILL CONTINUE INTO THE MORNING HOURS...THEN TAPER
OFF AS INVERTED TROUGH PULLS AWAY FROM SOUTHERN NEW ENGLAND AND HIGH
PRESSURE STARTS TO BUILD IN.  MOST LIKELY AREAS FOR CONTINUING
SHOWERS WILL BE ALONG THE IMMEDIATE EAST COAST OF MASSACHUSETTS.

AS THE DAY GOES ON...EXPECT A SLOW DRYING TREND AS HIGH PRESSURE
BUILDS INTO THE REGION.  CLOUDS WILL STICK AROUND WITH TEMPS
GENERALLY IN THE 30S.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
HIGHLIGHTS...

* INVERTED TROUGH WILL BRING RAIN/SNOW SHOWERS TO THE MASS EAST
  COASTLINE MONDAY INTO TUES MORNING.
* WEAK WAVE OF LOW PRESSURE MON NIGHT/TUESDAY COULD BRING WINTRY
  MIX TO INTERIOR
* ANOMALOUS SYSTEM ACROSS THE GREAT LAKES WILL BRING HEAVY
  RAIN...GUSTY WINDS AND COASTAL FLOODING CONCERNS AROUND CHRISTMAS
  EVE

OVERVIEW...

OVERALL 00Z GUIDANCE IS IN AGREEMENT SYNOPTICALLY WITH ISSUES ON
TIMING AND SMALLER SCALE FEATURES. IT REMAINS EVIDENT THAT AN
AMPLIFIED MID-UPPER LEVEL TROUGH AND PCPN FOCUSING LEAD SURFACE
LOW/FRONTAL SYSTEM WILL STEADILY PROGRESS TO THE EAST-CENTRAL U.S.
TUE AS EMBEDDED IMPULSES DIG TO THE LEE OF AN AMPLIFIED ERN
PACIFIC/WEST COAST RIDGE ALOFT. THE SUPPORTING AND INCREASINGLY
NEGATIVE-TILT TROUGH ALOFT WORKS OVER THE ERN US AND OUT THROUGH THE
NERN STATES INTO DAYS 4/5 WED/THU.  MODELS/ENSEMBLES HAVE BEEN
FAIRLY CONSISTENT ON THIS AMPLIFIED PATTERN AND THE MOST RECENT
GEFS/ECMWF ENSEMBLE GUIDANCE SHOW GOOD CORRELATION TO NEXT THURSDAY.

HIGH PRESSURE AND UPPER LEVEL RIDGE OVER THE REGION WILL BEGIN TO
EXIT BY MONDAY. AT THE SURFACE APPEARS ANOTHER INVERTED
TROUGH/ONSHORE FLOW WILL YIELD TO PRECIP ALONG THE MASS COASTLINE ON
MONDAY. ASIDE FROM THIS QUICK MESOSCALE EVENT THE MAIN FOCUS IS ON
THE LONGWAVE DIGGING TROUGH OVER THE CENTRAL CONUS WHICH WILL PUSH A
FEW SHORTWAVES THROUGH THE FLOW. FIRST ONE DEVELOPS A WEAK WAVE
MOVING TOWARDS THE REGION LATE MONDAY INTO TUESDAY. THERE IS STILL
SOME UNCERTAINTY WITH THE LOCATION/STRENGTH OF THIS SYSTEM BUT
APPEARS THAT THERE IS THE POSSIBILITY OF A SNOW/WINTRY MIX IN THE
INTERIOR. AS THIS SYSTEM DEPARTS AN ANOMALOUS LOW OVER THE GREAT
LAKES WILL DEVELOP A SECONDARY LOW JUST WEST OF SOUTHERN NEW ENGLAND
PER ENSEMBLE GUIDANCE. STILL A SOME SPREAD BUT IF THIS DOUBLE LOW
DOES DEVELOP THEN THE RAIN AND WIND ASPECT OF THE SYSTEM
INCREASES...DETAILS BELOW. STILL NEED TO WORK OUT MINOR DETAILS
WITH THIS PARTICULAR SYSTEM BUT WITH 3 TO 4 STANDARD DEVIATIONS
AWAY AND GENERAL MODEL AGREEMENT HAVE HIGH CONFIDENCE THIS SYSTEM
WILL IMPACT SOUTHERN NEW ENGLAND.

DETAILS...

SUNDAY NIGHT INTO TUESDAY...MODERATE CONFIDENCE.

HIGH PRESSURE AND UPPER LEVEL RIDGE WILL BEGIN TO MOVE OFFSHORE AS
DIGGING TROUGH BEGINS TO SET-UP OVER THE CENTRAL CONUS. APPEARS
ANOTHER MESOSCALE INVERTED TROUGH WILL SET UP ON MONDAY AND LAST
INTO EARLY TUESDAY MORNING. GUIDANCE SHOWS THAT RAIN/SNOW SHOWERS
WILL DEVELOP ALONG THE MASS EAST COASTLINE THANKS TO ONSHORE
EASTERLY FLOW. APPEARS THE COLUMN WILL SATURATE PER BUFKIT
SOUNDINGS AND SOUTHERLY FLOW ALOFT. BOTH THE NAM AND GFS SHOW QPF
MAKING IT ONSHORE DURING THIS TIME FRAME. HOWEVER THE EC IS
SLIGHTLY SLOWER AND KEEP THE BULK OF THE PRECIP JUST OFFSHORE. ADD
A CHANCE OF POPS DUE TO THE NAM/GFS MODEL CONTINUITY.

BY LATE MONDAY NIGHT INTO TUESDAY A SOUTHERN BRANCH STORM SYSTEM
FORMS ALONG THE SE COAST AND TAKES A TRACK OFF THE MID ATLANTIC
COAST. THIS SYSTEM GETS CAUGHT UP WITH THE OVERALL LARGE SCALE
AMPLIFICATION OF THE UPPER AIR PATTERN. THERE IS DECENT WARM
ADVECTION WITH COLD AIR DAMMING ACROSS THE INTERIOR. BIGGEST
QUESTION WILL BE IS THERE ENOUGH MOISTURE FOR PRECIP DURING THIS
TIME FRAME. IF PRECIP OVERRUNS THEN COULD SEE FREEZING RAIN/DRIZZLE
ACROSS THE INTERIOR LATE MONDAY INTO TUESDAY MORNING. DURING THE DAY
ON TUESDAY...GOOD AMOUNT OF WARM AIR WILL PUSH SURFACE TEMPS ABOVE
FREEZING ALLOWING FOR ANY PRECIP TO BE MORE OF THE LIQUID VARIETY
AHEAD OF THE CHRISTMAS EVE STORM. HOWEVER GUIDANCE IS ALWAYS TOO
FAST IN SCOURING TEMPS OUT ESP ACROSS THE CT VALLEY SO WE WILL NEED
TO MONITOR THIS CLOSELY...ESP DUE TO LIGHT WINDS AND THE HIGH IN
EASTERN CANADA.

WE COULD ALSO SEE SOME MINOR COASTAL FLOODING CONCERNS ON TUESDAY. SEE
BELOW FOR MORE DETAILS.

WEDNESDAY INTO THURSDAY...HIGH CONFIDENCE IN SYSTEM LOW CONFIDENCE
ON DETAILS.

STRONG ANOMALOUS SYSTEM WILL STRENGTHEN OVER THE GREAT
LAKES...DEVELOPING A POTENTIAL SECONDARY SURFACE LOW JUST WEST OF
SOUTHERN NEW ENGLAND. STILL A LOT OF DETAILS TO WORK OUT AS THIS
SYSTEM IS STILL 5 DAYS AWAY...HOWEVER ENSEMBLES CONTINUE TO SHOW
STRONG AGREEMENT SO HAVE INCREASING CONFIDENCE THAT A POTENT STORM
WILL OCCUR. LATEST 00Z GUIDANCE SHOWS THAT MOST PRECIP WILL BE
LIQUID WITH A DEEP SUBTROPICAL CONNECTION BACK ACROSS THE GULF OF
MEXICO...PW ANOMALIES FORECAST TO RISE BETWEEN +3 TO +4. CURRENT
PWATS ARE PROGGED ABOVE 1.6 INCHES SO HAVE CONTINUED THE CATEGORICAL
POPS. TEMPERATURES WILL BE WELL ABOVE AVERAGE...IN FACT WE MAY BE
CLOSE AT BREAKING RECORD HIGH TEMPS IF TEMPS WARM TO 60F OR ABOVE ON
CHRISTMAS EVE.  AS THE SYSTEM WRAPS UP INTO CANADA...COLD AIR
ADVECTION SHOULD CIRCULATE AROUND AND BEGIN A TRANSITION FROM
SOUTHWEST TO NORTHEAST IN TURNING P-TYPE TO SNOW. HOWEVER LATEST
GUIDANCE DOES SHOW A QUICK MOVING DRY SLOT SO SNOWFALL WILL STRUGGLE
DUE TO LACK OF MOISTURE.

THIS SYSTEM IS QUITE POTENT SO WE WILL NEED TO WATCH FOR POTENTIAL
HAZARDS. CURRENTLY THINK THAT WE COULD POSSIBLE URBAN FLOODING
ISSUES AS MODELS PROGGED WELL OVER 1.5 INCHES OF QPF. LATEST EC EVEN
SHOWS 2.5 INCHES OF QPF IS POSSIBLE. THE GEFS SHOW A MOISTURE FLUX
AT 850 MB BEING 4 TO 5 STANDARD DEVIATIONS AWAY...AND WITH THE
TROPICAL CONNECTION AND STRONG SOUTHERLY FLOW COULD SEE HIGHER
AMOUNTS DUE TO TOPOGRAPHY ENHANCEMENTS. RAIN FALL RECORDS MAY FALL
IF EVERYTHING FALLS INTO PLACE.

ALSO BELIEVE THAT WE MAY SEE SOME WIND ISSUES WITH THIS SYSTEM.
GUIDANCE RIGHT NOW IS SHOWING A 45 TO 55 KT JET AT 925 MB...HOWEVER
IT WILL BE HARD TO BREAK THE INVERSION WITH THE SOUTHERLY FLOW.
RIGHT NOW BELIEVE THAT WIND ADVISORIES MAY BE NEEDED BUT IF THIS
SYSTEM STRENGTHEN EVEN MORE SO A STRONGER JET IS POSSIBLE.

CONTINUED THE MENTIONED OF ISOLATED THUNDER IN THE FORECAST PER PREV
FORECASTER SUGGESTION. BELIEVE IT COULD BE POSSIBLE AS SOUTHERN NEW
ENGLAND WILL BE IN THE WARM SECTOR...WITH THE ANOMALOUS JET AND
SHOWALTERS CLOSE TO ZERO.

FRIDAY...LOW CONFIDENCE.

ONCE UPPER LEVEL LOW MOVES INTO SOUTHERN CANADA...EXPECT A RATHER
FAST UPPER W FLOW IN PLACE. MAY SEE LEFTOVER SNOW SHOWERS BUT TEMPS
WILL FALL BACK CLOSE TO SEASONAL NORMS.

&&

.AVIATION /21Z SATURDAY THROUGH THURSDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH SUNDAY/...

THROUGH 00Z...MODERATE CONFIDENCE. MVFR CIGS WILL CONTINUE TO
OVERSPREAD EASTERN NEW ENGLAND AND EVENTUALLY OVERSPREAD THE INTERIOR
THIS AFTERNOON. SCATTERED SHOWERS ACROSS PORTIONS OF EASTERN
MASSACHUSETTS THIS AFTERNOON. MAINLY SNOW SHOWERS TO THE NORTH AND
WEST OF CAPE COD CANAL...RAIN SHOWERS SOUTH AND EAST. LOCALIZED
IFR CONDITIONS POSSIBLE JUST INLAND FROM THE SOUTHEAST NEW ENGLAND
COAST...WHERE SNOW IS FALLING.

TONIGHT AND SUNDAY...MODERATE CONFIDENCE.  MVFR CONDITIONS DOMINATE
IN LOWER CLOUDS AND SCATTERED SHOWERS. LOCALIZED IFR CONDITIONS
POSSIBLE WITH THE BEST CHANCE IN SNOW SHOWERS. PRECIPITATION
AFFECTS MAINLY EASTERN NEW ENGLAND BUT STILL SOME SCATTERED
ACTIVITY ACROSS WESTERN NEW ENGLAND. MAINLY SNOW SHOWERS TO THE
NORTH AND WEST OF CAPE COD CANAL...RAIN SHOWERS SOUTH AND EAST.

KBOS TERMINAL...MODERATE CONFIDENCE IN TAF. FLURRIES AND SNOW
SHOWERS MAY AFFECT THE TERMINAL BY 21Z.

KBDL TERMINAL...MODERATE CONFIDENCE IN TAF.

OUTLOOK...SUNDAY NIGHT THROUGH WEDNESDAY...

MONDAY INTO TUESDAY...MODERATE CONFIDENCE. EXPECT MOSTLY
VFR...ISOLATED MVFR ALONG THE MASS EAST COASTLINE IN RAIN/SNOW
SHOWERS.

TUESDAY NIGHT INTO WEDNESDAY...MODERATE CONFIDENCE. CONDITIONS WILL
BE DETERIORATING AS HEAVY DOWNPOURS...ISO THUNDER AND GUSTY SOUTHERLY
WINDS MOVE INTO THE REGION BY WEDNESDAY. COULD SEE MVFR TO IFR
CONDITIONS IN CIGS AND VSBYS.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

HIGH CONFIDENCE. HIGH PRESSURE ACROSS QUEBEC WILL RESULT IN
PERSISTENT NORTHEAST WINDS ACROSS THE WATERS THROUGH THE WEEKEND.
WIND GUSTS UP TO 20 KNOTS WITH SEAS BETWEEN 2 AND 4 FEET ARE
EXPECTED FOR MOST WATERS...SO NO HEADLINES PLANNED.

THERE IS A LOW PROBABILITY THAT A BRIEF SURGE OF NORTHEAST WIND
GUSTS NEAR 25 KNOTS WITH MARGINAL 5 FOOT SEAS COULD AFFECT OUR
NORTHERN WATERS LATE TONIGHT INTO SUN MORNING...BUT NOT CONFIDENT
ENOUGH TO ISSUE ANY HEADLINES AT THIS POINT.

OUTLOOK...SUNDAY NIGHT INTO WEDNESDAY...MODERATE TO HIGH
CONFIDENCE.

SUNDAY INTO MONDAY. CONTINUOUS NORTHEAST FLOW WILL KEEP SEAS CHOPPY.
LINGERING NORTHEAST SWELL MAY BUMP SEAS ABOVE 5FT ESP ACROSS THE
NORTHEASTERN WATERS. SCA MAY BE NEEDED...BUT LOWER CONFIDENCE.

TUESDAY INTO WEDNESDAY...NE WINDS WILL INCREASE...GUSTING TO 30 KT
TUE THEN SHIFT TO SE GUSTING TO 30-35 KT WED...HIGHEST ON THE OUTER
WATERS. SEAS BUILD UP TO 7-11 FT BY WED. GALES WILL BE NEEDED.

&&

.TIDES/COASTAL FLOODING...
HIGH ASTRONOMICAL TIDES WILL OCCUR TUESDAY THROUGH THURSDAY. BREAKING
IT DOWN...ON TUESDAY HIGH TIDE AT BOSTON WILL BE 11.6 FT. THERE WILL
BE ONSHORE FLOW DURING THIS HIGH TIDE ALLOWING FOR MINOR SPLASHOVER.
IF WIND GUSTS INCREASE THEN COULD POSSIBLE SEE MINOR COASTAL
FLOODING.

ON WEDNESDAY...WINDS WILL SWITCH TO A MORE SOUTHEASTERLY FLOW DURING
THE DAY AND INCREASE QUICKLY FROM APPROACHING SYSTEM AND DESCENT
PRESSURE FALLS. WEDNESDAY AFTERNOON HIGH TIDE IN BOSTON IS 11.7 FT
AND WITH ANY STRENGTH ON THE EASTERLY WIND FLOW WILL PUSH THE TIDE
OVER. RIGHT NOW BELIEVE MINOR COASTAL FLOODING IS POSSIBLE ALONG THE
EAST COASTLINE. HOWEVER WEDNESDAY EVENING...THE WIND GOES IN A MORE
SOUTHERLY DIRECTION AND HIGH TIDE IN PROVIDENCE WILL BE 5.2 FT. 925
MB LLJ STRENGTHENS TO 50-60 KTS WHICH COULD PUSH A DESCENT SURGE UP
ALONG THE SOUTH COAST DURING THE TIME OF HIGH TIDE. THINKING THAT
MINOR COASTAL FLOODING COULD OCCUR BUT CANNOT RULE OUT MODERATE
ALONG THE SOUTH COAST...ESP IF LLJ STRENGTHENS EVEN MORE.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...DUNTEN/RLG
NEAR TERM...RLG
SHORT TERM...RLG
LONG TERM...DUNTEN
AVIATION...DUNTEN/RLG
MARINE...DUNTEN/RLG
TIDES/COASTAL FLOODING...



000
FXUS61 KBOX 201746
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
1246 PM EST SAT DEC 20 2014

.SYNOPSIS...
SCATTERED SNOW/RAIN SHOWERS WILL GRADUALLY OVERSPREAD THE REGION
FROM EAST TO WEST THIS AFTERNOON THROUGH SUN. WEAK LOW PRESSURE
WILL PASS SOUTH OF NEW ENGLAND BRINGING ANOTHER PERIOD OF PRECIP
MON NIGHT AND TUE. A MUCH STRONGER STORM PASSING WEST OF NEW
ENGLAND WILL BRING HEAVY RAINFALL...GUSTY WINDS AND COASTAL
FLOODING CONCERNS TO THE REGION WED INTO WED EVENING. DRY BUT VERY
WINDY CONDITIONS FOLLOW FOR CHRISTMAS DAY INTO FRI.

&&

.NEAR TERM /THROUGH TONIGHT/...
1245 PM UPDATE...SNOW SHOWERS CONTINUE TO AFFECT PORTIONS OF
EASTERN MASSACHUSETTS THIS AFTERNOON. THEY ARE STRUGGLING TO MOVE
WESTWARD OF CAPE ANN AND EASTERN NORFOLK COUNTY DUE TO MUCH DRIER
AIR. EVENTUALLY THE SHOWERS WILL OVERCOME THE DRIER AIR BUT EXPECT
THIS TO TAKE ANOTHER COUPLE OF HOURS...DEPENDING ON HOW QUICKLY
THE WINDS TURN TO THE NORTHEAST.

PREVIOUS DISCUSSION FOLLOWS...

INTERESTING MESOSCALE SETUP AS AN INVERTED TROUGH COMBINES WITH SOME
OCEAN ENHANCEMENT.  APPROACHING UPPER LEVEL SHORTWAVE WILL ALLOW FOR
EASTERLY FLOW JUST OFF THE GROUND.  THIS COMBINED WITH NORTHEAST
SURFACE WINDS WILL ALLOW LOW LEVEL OF THE ATMOSPHERE TO MOISTEN.
SOUNDINGS ACROSS EASTERN NEW ENGLAND BECOME SATURATED ALL THE WAY UP
TO THE -9C LAYER JUST ABOVE 850 MB.  THIS IS FAVORABLE FOR SOME
DECENT SNOW GROWTH...ITS JUST LOWER IN THE ATMOSPHERE THAN WE
TYPICALLY SEE WITH MORE SYNOPTIC SNOW EVENTS.  WHILE THIS IS NOT A
TRUE OCEAN EFFECT EVENT...DELTA T VALUES FROM THE MIXED LAYER TO THE
OCEAN ARE AROUND 15C.  THEREFORE...EXPECT SOME OCEAN ENHANCEMENT.

TIMING:

WHILE FLURRIES/LIGHT SNOW SHOWERS MAY OCCUR ACROSS FAR SOUTHEAST NEW
ENGLAND THIS MORNING.  THE MORE SUBSTANTIAL  PRECIPITATION SHOULD
OVERSPREAD PLYMOUTH COUNTY AS WELL AS THE CAPE AND ISLANDS THIS
AFTERNOON.  GIVEN EASTERLY FLOW JUST OFF THE GROUND...EXPECT SNOW
SHOWERS TO OVERSPREAD MOST OF EASTERN NEW ENGLAND THIS EVENING AS
LOW LEVELS MOISTEN.  IN FACT...SHOULD SEE AT LEAST SOME SCATTERED
SNOW SHOWERS AFFECT EVEN OUR FAR WESTERN ZONES.

PTYPE:

MAINLY SNOW FOR ALL BUT PORTIONS OF COASTAL PLYMOUTH COUNTY AND ONTO
THE CAPE/ISLANDS.  A SUBTLE COASTAL FRONT LOOKS TO SETUP ACROSS
SOUTHEAST COASTAL PLYMOUTH COUNTY.  PTYPE WILL BE SNOW TO THE
NORTHWEST OF THIS REGION...BUT ENOUGH MILD AIR SHOULD COME IN OFF
THE OCEAN FOR A CHANGE TO RAIN SHOWERS SOUTHEAST OF THIS REGION.
NOT EXPECTING THE POSITION OF THIS SUBTLE BOUNDARY TO CHANGE MUCH
THROUGH SUNDAY MORNING.

SNOW ACCUMULATIONS:

WE ARE GENERALLY LOOKING AT A COATING TO 2 INCHES OF SNOW ACROSS
MOST OF THE REGION.  THE MAIN FOCUS FOR 1 TO 2 INCHES WILL BE ACROSS
PORTIONS OF SOUTHEAST MA...AWAY FROM THE SOUTHEAST PLYMOUTH COUNTY
COAST.  ALSO...THE WORCESTER HILLS INTO NORTHWEST RHODE ISLAND MIGHT
BE ANOTHER AREA AS A RESULT OF THE SUBTLE UPSLOPE COMPONENT TO THE
WIND.  YOU CAN ACTUALLY SEE THAT IN SOME OF THE HIGH RESOLUTION
MODEL GUIDANCE.

THERE IS ONE AREA TO WATCH IN PARTICULAR...FROM NORTHWEST PLYMOUTH
COUNTY AND INTO NORFOLK COUNTY BASED ON MESOSCALE MODELS AND PATTERN
RECOGNITION.  WOULD NOT BE SURPRISED TO SEE VERY LOCALIZED 3 TO 4
INCH SNOW AMOUNTS...GIVEN SOME OCEAN ENHANCEMENT AND A LITTLE FOCUS
ON THE COASTAL FRONT.  WILL TRY TO HIGHLIGHT THIS AREA IN OUR
SNOWFALL AND PROBABILISTIC GRAPHICS.

&&

.SHORT TERM /SUNDAY/...
SCATTERED SNOW SHOWERS WILL CONTINUE DURING THE MORNING WITH
MOIST EASTERLY FLOW IN THE LOW LEVELS. AGAIN...PTYPE WILL BE SNOW
EXCEPT ACROSS SOUTHEAST PLYMOUTH COUNTY/CAPE AND ISLANDS WHERE
BOUNDARY LAYER WILL PROBABLY BE WARM ENOUGH FOR RAIN SHOWERS.
WHILE SOME LIGHT PRECIPITATION MAY LINGER INTO SUNDAY
AFTERNOON...EXPECT A DECREASE IN AREAL COVERAGE THROUGH THE
AFTERNOON AS LOW LEVEL LIFT WEAKENS. IT WILL REMAIN CLOUDY THOUGH
WITH TEMPS IN THE 30S.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
HIGHLIGHTS...

* INVERTED TROUGH WILL BRING RAIN/SNOW SHOWERS TO THE MASS EAST
  COASTLINE MONDAY INTO TUES MORNING.
* WEAK WAVE OF LOW PRESSURE MON NIGHT/TUESDAY COULD BRING WINTRY
  MIX TO INTERIOR
* ANOMALOUS SYSTEM ACROSS THE GREAT LAKES WILL BRING HEAVY
  RAIN...GUSTY WINDS AND COASTAL FLOODING CONCERNS AROUND CHRISTMAS
  EVE

OVERVIEW...

OVERALL 00Z GUIDANCE IS IN AGREEMENT SYNOPTICALLY WITH ISSUES ON
TIMING AND SMALLER SCALE FEATURES. IT REMAINS EVIDENT THAT AN
AMPLIFIED MID-UPPER LEVEL TROUGH AND PCPN FOCUSING LEAD SURFACE
LOW/FRONTAL SYSTEM WILL STEADILY PROGRESS TO THE EAST-CENTRAL U.S.
TUE AS EMBEDDED IMPULSES DIG TO THE LEE OF AN AMPLIFIED ERN
PACIFIC/WEST COAST RIDGE ALOFT. THE SUPPORTING AND INCREASINGLY
NEGATIVE-TILT TROUGH ALOFT WORKS OVER THE ERN US AND OUT THROUGH THE
NERN STATES INTO DAYS 4/5 WED/THU.  MODELS/ENSEMBLES HAVE BEEN
FAIRLY CONSISTENT ON THIS AMPLIFIED PATTERN AND THE MOST RECENT
GEFS/ECMWF ENSEMBLE GUIDANCE SHOW GOOD CORRELATION TO NEXT THURSDAY.

HIGH PRESSURE AND UPPER LEVEL RIDGE OVER THE REGION WILL BEGIN TO
EXIT BY MONDAY. AT THE SURFACE APPEARS ANOTHER INVERTED
TROUGH/ONSHORE FLOW WILL YIELD TO PRECIP ALONG THE MASS COASTLINE ON
MONDAY. ASIDE FROM THIS QUICK MESOSCALE EVENT THE MAIN FOCUS IS ON
THE LONGWAVE DIGGING TROUGH OVER THE CENTRAL CONUS WHICH WILL PUSH A
FEW SHORTWAVES THROUGH THE FLOW. FIRST ONE DEVELOPS A WEAK WAVE
MOVING TOWARDS THE REGION LATE MONDAY INTO TUESDAY. THERE IS STILL
SOME UNCERTAINTY WITH THE LOCATION/STRENGTH OF THIS SYSTEM BUT
APPEARS THAT THERE IS THE POSSIBILITY OF A SNOW/WINTRY MIX IN THE
INTERIOR. AS THIS SYSTEM DEPARTS AN ANOMALOUS LOW OVER THE GREAT
LAKES WILL DEVELOP A SECONDARY LOW JUST WEST OF SOUTHERN NEW ENGLAND
PER ENSEMBLE GUIDANCE. STILL A SOME SPREAD BUT IF THIS DOUBLE LOW
DOES DEVELOP THEN THE RAIN AND WIND ASPECT OF THE SYSTEM
INCREASES...DETAILS BELOW. STILL NEED TO WORK OUT MINOR DETAILS
WITH THIS PARTICULAR SYSTEM BUT WITH 3 TO 4 STANDARD DEVIATIONS
AWAY AND GENERAL MODEL AGREEMENT HAVE HIGH CONFIDENCE THIS SYSTEM
WILL IMPACT SOUTHERN NEW ENGLAND.

DETAILS...

SUNDAY NIGHT INTO TUESDAY...MODERATE CONFIDENCE.

HIGH PRESSURE AND UPPER LEVEL RIDGE WILL BEGIN TO MOVE OFFSHORE AS
DIGGING TROUGH BEGINS TO SET-UP OVER THE CENTRAL CONUS. APPEARS
ANOTHER MESO-SCALE INVERTED TROUGH WILL SET UP ON MONDAY AND LAST
INTO EARLY TUESDAY MORNING. GUIDANCE SHOWS THAT RAIN/SNOW SHOWERS
WILL DEVELOP ALONG THE MASS EAST COASTLINE THANKS TO ONSHORE
EASTERLY FLOW. APPEARS THE COLUMN WILL SATURATE PER BUFKIT SOUNDINGS
AND SOUTHERLY FLOW ALOFT. BOTH THE NAM AND GFS SHOW QPF MAKING IT
ONSHORE DURING THIS TIME FRAME. HOWEVER THE EC IS SLIGHTLY SLOWER
AND KEEP THE BULK OF THE PRECIP JUST OFFSHORE. ADD A CHANCE OF POPS
DUE TO THE NAM/GFS MODEL CONTINUITY.

BY LATE MONDAY NIGHT INTO TUESDAY A SOUTHERN BRANCH STORM SYSTEM
FORMS ALONG THE SE COAST AND TAKES A TRACK OFF THE MID ATLANTIC
COAST. THIS SYSTEM GETS CAUGHT UP WITH THE OVERALL LARGE SCALE
AMPLIFICATION OF THE UPPER AIR PATTERN. THERE IS DECENT WARM
ADVECTION WITH COLD AIR DAMMING ACROSS THE INTERIOR. BIGGEST
QUESTION WILL BE IS THERE ENOUGH MOISTURE FOR PRECIP DURING THIS
TIME FRAME. IF PRECIP OVERRUNS THEN COULD SEE FREEZING RAIN/DRIZZLE
ACROSS THE INTERIOR LATE MONDAY INTO TUESDAY MORNING. DURING THE DAY
ON TUESDAY...GOOD AMOUNT OF WARM AIR WILL PUSH SURFACE TEMPS ABOVE
FREEZING ALLOWING FOR ANY PRECIP TO BE MORE OF THE LIQUID VARIETY
AHEAD OF THE CHRISTMAS EVE STORM. HOWEVER GUIDANCE IS ALWAYS TOO
FAST IN SCOURING TEMPS OUT ESP ACROSS THE CT VALLEY SO WE WILL NEED
TO MONITOR THIS CLOSELY...ESP DUE TO LIGHT WINDS AND THE HIGH IN
EASTERN CANADA.

WE COULD ALSO SEE SOME MINOR COASTAL FLOODING CONCERNS ON TUESDAY. SEE
BELOW FOR MORE DETAILS.

WEDNESDAY INTO THURSDAY...HIGH CONFIDENCE IN SYSTEM LOW CONFIDENCE
ON DETAILS.

STRONG ANOMALOUS SYSTEM WILL STRENGTHEN OVER THE GREAT
LAKES...DEVELOPING A POTENTIAL SECONDARY SURFACE LOW JUST WEST OF
SOUTHERN NEW ENGLAND. STILL A LOT OF DETAILS TO WORK OUT AS THIS
SYSTEM IS STILL 5 DAYS AWAY...HOWEVER ENSEMBLES CONTINUE TO SHOW
STRONG AGREEMENT SO HAVE INCREASING CONFIDENCE THAT A POTENT STORM
WILL OCCUR. LATEST 00Z GUIDANCE SHOWS THAT MOST PRECIP WILL BE
LIQUID WITH A DEEP SUBTROPICAL CONNECTION BACK ACROSS THE GULF OF
MEXICO...PW ANOMALIES FORECAST TO RISE BETWEEN +3 TO +4. CURRENT
PWATS ARE PROGGED ABOVE 1.6 INCHES SO HAVE CONTINUED THE CATEGORICAL
POPS. TEMPERATURES WILL BE WELL ABOVE AVERAGE...IN FACT WE MAY BE
CLOSE AT BREAKING RECORD HIGH TEMPS IF TEMPS WARM TO 60F OR ABOVE ON
CHRISTMAS EVE.  AS THE SYSTEM WRAPS UP INTO CANADA...COLD AIR
ADVECTION SHOULD CIRCULATE AROUND AND BEGIN A TRANSITION FROM
SOUTHWEST TO NORTHEAST IN TURNING P-TYPE TO SNOW. HOWEVER LATEST
GUIDANCE DOES SHOW A QUICK MOVING DRY SLOT SO SNOWFALL WILL STRUGGLE
DUE TO LACK OF MOISTURE.

THIS SYSTEM IS QUITE POTENT SO WE WILL NEED TO WATCH FOR POTENTIAL
HAZARDS. CURRENTLY THINK THAT WE COULD POSSIBLE URBAN FLOODING
ISSUES AS MODELS PROGGED WELL OVER 1.5 INCHES OF QPF. LATEST EC EVEN
SHOWS 2.5 INCHES OF QPF IS POSSIBLE. THE GEFS SHOW A MOISTURE FLUX
AT 850 MB BEING 4 TO 5 STANDARD DEVIATIONS AWAY...AND WITH THE
TROPICAL CONNECTION AND STRONG SOUTHERLY FLOW COULD SEE HIGHER
AMOUNTS DUE TO TOPOGRAPHY ENHANCEMENTS. RAIN FALL RECORDS MAY FALL
IF EVERYTHING FALLS INTO PLACE.

ALSO BELIEVE THAT WE MAY SEE SOME WIND ISSUES WITH THIS SYSTEM.
GUIDANCE RIGHT NOW IS SHOWING A 45 TO 55 KT JET AT 925 MB...HOWEVER
IT WILL BE HARD TO BREAK THE INVERSION WITH THE SOUTHERLY FLOW.
RIGHT NOW BELIEVE THAT WIND ADVISORIES MAY BE NEEDED BUT IF THIS
SYSTEM STRENGTHEN EVEN MORE SO A STRONGER JET IS POSSIBLE.

CONTINUED THE MENTIONED OF ISOLATED THUNDER IN THE FORECAST PER PREV
FORECASTER SUGGESTION. BELIEVE IT COULD BE POSSIBLE AS SOUTHERN NEW
ENGLAND WILL BE IN THE WARM SECTOR...WITH THE ANOMALOUS JET AND
SHOWALTERS CLOSE TO ZERO.

FRIDAY...LOW CONFIDENCE.

ONCE UPPER LEVEL LOW MOVES INTO SOUTHERN CANADA...EXPECT A RATHER
FAST UPPER W FLOW IN PLACE. MAY SEE LEFTOVER SNOW SHOWERS BUT TEMPS
WILL FALL BACK CLOSE TO SEASONAL NORMS.

&&

.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH SUNDAY/...

THROUGH 00Z...MODERATE CONFIDENCE. MVFR CIGS WILL CONTINUE TO
OVERSPREAD EASTERN NEW ENGLAND AND EVENTUALLY OVERSPREAD THE INTERIOR
THIS AFTERNOON. SCATTERED SHOWERS ACROSS PORTIONS OF EASTERN
MASSACHUSETTS THIS AFTERNOON. MAINLY SNOW SHOWERS TO THE NORTH AND
WEST OF CAPE COD CANAL...RAIN SHOWERS SOUTH AND EAST. LOCALIZED
IFR CONDITIONS POSSIBLE JUST INLAND FROM THE SOUTHEAST NEW ENGLAND
COAST...WHERE SNOW IS FALLING.

TONIGHT AND SUNDAY...MODERATE CONFIDENCE.  MVFR CONDITIONS DOMINATE
IN LOWER CLOUDS AND SCATTERED SHOWERS. LOCALIZED IFR CONDITIONS
POSSIBLE WITH THE BEST CHANCE IN SNOW SHOWERS. PRECIPITATION
AFFECTS MAINLY EASTERN NEW ENGLAND BUT STILL SOME SCATTERED
ACTIVITY ACROSS WESTERN NEW ENGLAND. MAINLY SNOW SHOWERS TO THE
NORTH AND WEST OF CAPE COD CANAL...RAIN SHOWERS SOUTH AND EAST.

KBOS TERMINAL...MODERATE CONFIDENCE IN TAF. FLURRIES AND SNOW
SHOWERS MAY AFFECT THE TERMINAL BY 21Z.

KBDL TERMINAL...MODERATE CONFIDENCE IN TAF.

OUTLOOK...SUNDAY NIGHT THROUGH WEDNESDAY...

MONDAY INTO TUESDAY...MODERATE CONFIDENCE. EXPECT MOSTLY
VFR...ISOLATED MVFR ALONG THE MASS EAST COASTLINE IN RAIN/SNOW
SHOWERS.

TUESDAY NIGHT INTO WEDNESDAY...MODERATE CONFIDENCE. CONDITIONS WILL
BE DETERIORATING AS HEAVY DOWNPOURS...ISO THUNDER AND GUSTY SOUTHERLY
WINDS MOVE INTO THE REGION BY WEDNESDAY. COULD SEE MVFR TO IFR
CONDITIONS IN CIGS AND VSBYS.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /TODAY THROUGH SUNDAY/...HIGH CONFIDENCE.

HIGH PRESSURE ACROSS QUEBEC WILL RESULT IN PERSISTENT NORTHEAST
WINDS ACROSS THE WATERS THROUGH THE WEEKEND.  WIND GUSTS UP TO 20
KNOTS WITH SEAS BETWEEN 2 AND 4 FEET ARE EXPECTED FOR MOST
WATERS...SO NO HEADLINES PLANNED. THERE IS A LOW PROBABILITY THAT A
BRIEF SURGE OF NORTHEAST WIND GUSTS NEAR 25 KNOTS WITH MARGINAL 5
FOOT SEAS COULD AFFECT OUR NORTHERN WATERS LATE TONIGHT INTO SUN
MORNING...BUT NOT CONFIDENT ENOUGH TO ISSUE ANY HEADLINES AT THIS
POINT.

OUTLOOK...SUNDAY NIGHT INTO WEDNESDAY...MODERATE TO HIGH
CONFIDENCE.

SUNDAY INTO MONDAY. CONTINUOUS NORTHEAST FLOW WILL KEEP SEAS CHOPPY.
LINGERING NORTHEAST SWELL MAY BUMP SEAS ABOVE 5FT ESP ACROSS THE
NORTHEASTERN WATERS. SCA MAY BE NEEDED...BUT LOWER CONFIDENCE.

TUESDAY INTO WEDNESDAY...NE WINDS WILL INCREASE...GUSTING TO 30 KT
TUE THEN SHIFT TO SE GUSTING TO 30-35 KT WED...HIGHEST ON THE OUTER
WATERS. SEAS BUILD UP TO 7-11 FT BY WED. GALES WILL BE NEEDED.

&&

.TIDES/COASTAL FLOODING...
HIGH ASTRONOMICAL TIDES WILL OCCUR TUESDAY THROUGH THURSDAY. BREAKING
IT DOWN...ON TUESDAY HIGH TIDE AT BOSTON WILL BE 11.6 FT. THERE WILL
BE ONSHORE FLOW DURING THIS HIGH TIDE ALLOWING FOR MINOR SPLASHOVER.
IF WIND GUSTS INCREASE THEN COULD POSSIBLE SEE MINOR COASTAL
FLOODING.

ON WEDNESDAY...WINDS WILL SWITCH TO A MORE SOUTHEASTERLY FLOW DURING
THE DAY AND INCREASE QUICKLY FROM APPROACHING SYSTEM AND DESCENT
PRESSURE FALLS. WEDNESDAY AFTERNOON HIGH TIDE IN BOSTON IS 11.7 FT
AND WITH ANY STRENGTH ON THE EASTERLY WIND FLOW WILL PUSH THE TIDE
OVER. RIGHT NOW BELIEVE MINOR COASTAL FLOODING IS POSSIBLE ALONG THE
EAST COASTLINE. HOWEVER WEDNESDAY EVENING...THE WIND GOES IN A MORE
SOUTHERLY DIRECTION AND HIGH TIDE IN PROVIDENCE WILL BE 5.2 FT. 925
MB LLJ STRENGTHENS TO 50-60 KTS WHICH COULD PUSH A DESCENT SURGE UP
ALONG THE SOUTH COAST DURING THE TIME OF HIGH TIDE. THINKING THAT
MINOR COASTAL FLOODING COULD OCCUR BUT CANNOT RULE OUT MODERATE
ALONG THE SOUTH COAST...ESP IF LLJ STRENGTHENS EVEN MORE.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...DUNTEN/RLG
NEAR TERM...FRANK/RLG
SHORT TERM...FRANK
LONG TERM...DUNTEN
AVIATION...DUNTEN/RLG
MARINE...FRANK/DUNTEN
TIDES/COASTAL FLOODING...



000
FXUS61 KBOX 201746
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
1246 PM EST SAT DEC 20 2014

.SYNOPSIS...
SCATTERED SNOW/RAIN SHOWERS WILL GRADUALLY OVERSPREAD THE REGION
FROM EAST TO WEST THIS AFTERNOON THROUGH SUN. WEAK LOW PRESSURE
WILL PASS SOUTH OF NEW ENGLAND BRINGING ANOTHER PERIOD OF PRECIP
MON NIGHT AND TUE. A MUCH STRONGER STORM PASSING WEST OF NEW
ENGLAND WILL BRING HEAVY RAINFALL...GUSTY WINDS AND COASTAL
FLOODING CONCERNS TO THE REGION WED INTO WED EVENING. DRY BUT VERY
WINDY CONDITIONS FOLLOW FOR CHRISTMAS DAY INTO FRI.

&&

.NEAR TERM /THROUGH TONIGHT/...
1245 PM UPDATE...SNOW SHOWERS CONTINUE TO AFFECT PORTIONS OF
EASTERN MASSACHUSETTS THIS AFTERNOON. THEY ARE STRUGGLING TO MOVE
WESTWARD OF CAPE ANN AND EASTERN NORFOLK COUNTY DUE TO MUCH DRIER
AIR. EVENTUALLY THE SHOWERS WILL OVERCOME THE DRIER AIR BUT EXPECT
THIS TO TAKE ANOTHER COUPLE OF HOURS...DEPENDING ON HOW QUICKLY
THE WINDS TURN TO THE NORTHEAST.

PREVIOUS DISCUSSION FOLLOWS...

INTERESTING MESOSCALE SETUP AS AN INVERTED TROUGH COMBINES WITH SOME
OCEAN ENHANCEMENT.  APPROACHING UPPER LEVEL SHORTWAVE WILL ALLOW FOR
EASTERLY FLOW JUST OFF THE GROUND.  THIS COMBINED WITH NORTHEAST
SURFACE WINDS WILL ALLOW LOW LEVEL OF THE ATMOSPHERE TO MOISTEN.
SOUNDINGS ACROSS EASTERN NEW ENGLAND BECOME SATURATED ALL THE WAY UP
TO THE -9C LAYER JUST ABOVE 850 MB.  THIS IS FAVORABLE FOR SOME
DECENT SNOW GROWTH...ITS JUST LOWER IN THE ATMOSPHERE THAN WE
TYPICALLY SEE WITH MORE SYNOPTIC SNOW EVENTS.  WHILE THIS IS NOT A
TRUE OCEAN EFFECT EVENT...DELTA T VALUES FROM THE MIXED LAYER TO THE
OCEAN ARE AROUND 15C.  THEREFORE...EXPECT SOME OCEAN ENHANCEMENT.

TIMING:

WHILE FLURRIES/LIGHT SNOW SHOWERS MAY OCCUR ACROSS FAR SOUTHEAST NEW
ENGLAND THIS MORNING.  THE MORE SUBSTANTIAL  PRECIPITATION SHOULD
OVERSPREAD PLYMOUTH COUNTY AS WELL AS THE CAPE AND ISLANDS THIS
AFTERNOON.  GIVEN EASTERLY FLOW JUST OFF THE GROUND...EXPECT SNOW
SHOWERS TO OVERSPREAD MOST OF EASTERN NEW ENGLAND THIS EVENING AS
LOW LEVELS MOISTEN.  IN FACT...SHOULD SEE AT LEAST SOME SCATTERED
SNOW SHOWERS AFFECT EVEN OUR FAR WESTERN ZONES.

PTYPE:

MAINLY SNOW FOR ALL BUT PORTIONS OF COASTAL PLYMOUTH COUNTY AND ONTO
THE CAPE/ISLANDS.  A SUBTLE COASTAL FRONT LOOKS TO SETUP ACROSS
SOUTHEAST COASTAL PLYMOUTH COUNTY.  PTYPE WILL BE SNOW TO THE
NORTHWEST OF THIS REGION...BUT ENOUGH MILD AIR SHOULD COME IN OFF
THE OCEAN FOR A CHANGE TO RAIN SHOWERS SOUTHEAST OF THIS REGION.
NOT EXPECTING THE POSITION OF THIS SUBTLE BOUNDARY TO CHANGE MUCH
THROUGH SUNDAY MORNING.

SNOW ACCUMULATIONS:

WE ARE GENERALLY LOOKING AT A COATING TO 2 INCHES OF SNOW ACROSS
MOST OF THE REGION.  THE MAIN FOCUS FOR 1 TO 2 INCHES WILL BE ACROSS
PORTIONS OF SOUTHEAST MA...AWAY FROM THE SOUTHEAST PLYMOUTH COUNTY
COAST.  ALSO...THE WORCESTER HILLS INTO NORTHWEST RHODE ISLAND MIGHT
BE ANOTHER AREA AS A RESULT OF THE SUBTLE UPSLOPE COMPONENT TO THE
WIND.  YOU CAN ACTUALLY SEE THAT IN SOME OF THE HIGH RESOLUTION
MODEL GUIDANCE.

THERE IS ONE AREA TO WATCH IN PARTICULAR...FROM NORTHWEST PLYMOUTH
COUNTY AND INTO NORFOLK COUNTY BASED ON MESOSCALE MODELS AND PATTERN
RECOGNITION.  WOULD NOT BE SURPRISED TO SEE VERY LOCALIZED 3 TO 4
INCH SNOW AMOUNTS...GIVEN SOME OCEAN ENHANCEMENT AND A LITTLE FOCUS
ON THE COASTAL FRONT.  WILL TRY TO HIGHLIGHT THIS AREA IN OUR
SNOWFALL AND PROBABILISTIC GRAPHICS.

&&

.SHORT TERM /SUNDAY/...
SCATTERED SNOW SHOWERS WILL CONTINUE DURING THE MORNING WITH
MOIST EASTERLY FLOW IN THE LOW LEVELS. AGAIN...PTYPE WILL BE SNOW
EXCEPT ACROSS SOUTHEAST PLYMOUTH COUNTY/CAPE AND ISLANDS WHERE
BOUNDARY LAYER WILL PROBABLY BE WARM ENOUGH FOR RAIN SHOWERS.
WHILE SOME LIGHT PRECIPITATION MAY LINGER INTO SUNDAY
AFTERNOON...EXPECT A DECREASE IN AREAL COVERAGE THROUGH THE
AFTERNOON AS LOW LEVEL LIFT WEAKENS. IT WILL REMAIN CLOUDY THOUGH
WITH TEMPS IN THE 30S.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
HIGHLIGHTS...

* INVERTED TROUGH WILL BRING RAIN/SNOW SHOWERS TO THE MASS EAST
  COASTLINE MONDAY INTO TUES MORNING.
* WEAK WAVE OF LOW PRESSURE MON NIGHT/TUESDAY COULD BRING WINTRY
  MIX TO INTERIOR
* ANOMALOUS SYSTEM ACROSS THE GREAT LAKES WILL BRING HEAVY
  RAIN...GUSTY WINDS AND COASTAL FLOODING CONCERNS AROUND CHRISTMAS
  EVE

OVERVIEW...

OVERALL 00Z GUIDANCE IS IN AGREEMENT SYNOPTICALLY WITH ISSUES ON
TIMING AND SMALLER SCALE FEATURES. IT REMAINS EVIDENT THAT AN
AMPLIFIED MID-UPPER LEVEL TROUGH AND PCPN FOCUSING LEAD SURFACE
LOW/FRONTAL SYSTEM WILL STEADILY PROGRESS TO THE EAST-CENTRAL U.S.
TUE AS EMBEDDED IMPULSES DIG TO THE LEE OF AN AMPLIFIED ERN
PACIFIC/WEST COAST RIDGE ALOFT. THE SUPPORTING AND INCREASINGLY
NEGATIVE-TILT TROUGH ALOFT WORKS OVER THE ERN US AND OUT THROUGH THE
NERN STATES INTO DAYS 4/5 WED/THU.  MODELS/ENSEMBLES HAVE BEEN
FAIRLY CONSISTENT ON THIS AMPLIFIED PATTERN AND THE MOST RECENT
GEFS/ECMWF ENSEMBLE GUIDANCE SHOW GOOD CORRELATION TO NEXT THURSDAY.

HIGH PRESSURE AND UPPER LEVEL RIDGE OVER THE REGION WILL BEGIN TO
EXIT BY MONDAY. AT THE SURFACE APPEARS ANOTHER INVERTED
TROUGH/ONSHORE FLOW WILL YIELD TO PRECIP ALONG THE MASS COASTLINE ON
MONDAY. ASIDE FROM THIS QUICK MESOSCALE EVENT THE MAIN FOCUS IS ON
THE LONGWAVE DIGGING TROUGH OVER THE CENTRAL CONUS WHICH WILL PUSH A
FEW SHORTWAVES THROUGH THE FLOW. FIRST ONE DEVELOPS A WEAK WAVE
MOVING TOWARDS THE REGION LATE MONDAY INTO TUESDAY. THERE IS STILL
SOME UNCERTAINTY WITH THE LOCATION/STRENGTH OF THIS SYSTEM BUT
APPEARS THAT THERE IS THE POSSIBILITY OF A SNOW/WINTRY MIX IN THE
INTERIOR. AS THIS SYSTEM DEPARTS AN ANOMALOUS LOW OVER THE GREAT
LAKES WILL DEVELOP A SECONDARY LOW JUST WEST OF SOUTHERN NEW ENGLAND
PER ENSEMBLE GUIDANCE. STILL A SOME SPREAD BUT IF THIS DOUBLE LOW
DOES DEVELOP THEN THE RAIN AND WIND ASPECT OF THE SYSTEM
INCREASES...DETAILS BELOW. STILL NEED TO WORK OUT MINOR DETAILS
WITH THIS PARTICULAR SYSTEM BUT WITH 3 TO 4 STANDARD DEVIATIONS
AWAY AND GENERAL MODEL AGREEMENT HAVE HIGH CONFIDENCE THIS SYSTEM
WILL IMPACT SOUTHERN NEW ENGLAND.

DETAILS...

SUNDAY NIGHT INTO TUESDAY...MODERATE CONFIDENCE.

HIGH PRESSURE AND UPPER LEVEL RIDGE WILL BEGIN TO MOVE OFFSHORE AS
DIGGING TROUGH BEGINS TO SET-UP OVER THE CENTRAL CONUS. APPEARS
ANOTHER MESO-SCALE INVERTED TROUGH WILL SET UP ON MONDAY AND LAST
INTO EARLY TUESDAY MORNING. GUIDANCE SHOWS THAT RAIN/SNOW SHOWERS
WILL DEVELOP ALONG THE MASS EAST COASTLINE THANKS TO ONSHORE
EASTERLY FLOW. APPEARS THE COLUMN WILL SATURATE PER BUFKIT SOUNDINGS
AND SOUTHERLY FLOW ALOFT. BOTH THE NAM AND GFS SHOW QPF MAKING IT
ONSHORE DURING THIS TIME FRAME. HOWEVER THE EC IS SLIGHTLY SLOWER
AND KEEP THE BULK OF THE PRECIP JUST OFFSHORE. ADD A CHANCE OF POPS
DUE TO THE NAM/GFS MODEL CONTINUITY.

BY LATE MONDAY NIGHT INTO TUESDAY A SOUTHERN BRANCH STORM SYSTEM
FORMS ALONG THE SE COAST AND TAKES A TRACK OFF THE MID ATLANTIC
COAST. THIS SYSTEM GETS CAUGHT UP WITH THE OVERALL LARGE SCALE
AMPLIFICATION OF THE UPPER AIR PATTERN. THERE IS DECENT WARM
ADVECTION WITH COLD AIR DAMMING ACROSS THE INTERIOR. BIGGEST
QUESTION WILL BE IS THERE ENOUGH MOISTURE FOR PRECIP DURING THIS
TIME FRAME. IF PRECIP OVERRUNS THEN COULD SEE FREEZING RAIN/DRIZZLE
ACROSS THE INTERIOR LATE MONDAY INTO TUESDAY MORNING. DURING THE DAY
ON TUESDAY...GOOD AMOUNT OF WARM AIR WILL PUSH SURFACE TEMPS ABOVE
FREEZING ALLOWING FOR ANY PRECIP TO BE MORE OF THE LIQUID VARIETY
AHEAD OF THE CHRISTMAS EVE STORM. HOWEVER GUIDANCE IS ALWAYS TOO
FAST IN SCOURING TEMPS OUT ESP ACROSS THE CT VALLEY SO WE WILL NEED
TO MONITOR THIS CLOSELY...ESP DUE TO LIGHT WINDS AND THE HIGH IN
EASTERN CANADA.

WE COULD ALSO SEE SOME MINOR COASTAL FLOODING CONCERNS ON TUESDAY. SEE
BELOW FOR MORE DETAILS.

WEDNESDAY INTO THURSDAY...HIGH CONFIDENCE IN SYSTEM LOW CONFIDENCE
ON DETAILS.

STRONG ANOMALOUS SYSTEM WILL STRENGTHEN OVER THE GREAT
LAKES...DEVELOPING A POTENTIAL SECONDARY SURFACE LOW JUST WEST OF
SOUTHERN NEW ENGLAND. STILL A LOT OF DETAILS TO WORK OUT AS THIS
SYSTEM IS STILL 5 DAYS AWAY...HOWEVER ENSEMBLES CONTINUE TO SHOW
STRONG AGREEMENT SO HAVE INCREASING CONFIDENCE THAT A POTENT STORM
WILL OCCUR. LATEST 00Z GUIDANCE SHOWS THAT MOST PRECIP WILL BE
LIQUID WITH A DEEP SUBTROPICAL CONNECTION BACK ACROSS THE GULF OF
MEXICO...PW ANOMALIES FORECAST TO RISE BETWEEN +3 TO +4. CURRENT
PWATS ARE PROGGED ABOVE 1.6 INCHES SO HAVE CONTINUED THE CATEGORICAL
POPS. TEMPERATURES WILL BE WELL ABOVE AVERAGE...IN FACT WE MAY BE
CLOSE AT BREAKING RECORD HIGH TEMPS IF TEMPS WARM TO 60F OR ABOVE ON
CHRISTMAS EVE.  AS THE SYSTEM WRAPS UP INTO CANADA...COLD AIR
ADVECTION SHOULD CIRCULATE AROUND AND BEGIN A TRANSITION FROM
SOUTHWEST TO NORTHEAST IN TURNING P-TYPE TO SNOW. HOWEVER LATEST
GUIDANCE DOES SHOW A QUICK MOVING DRY SLOT SO SNOWFALL WILL STRUGGLE
DUE TO LACK OF MOISTURE.

THIS SYSTEM IS QUITE POTENT SO WE WILL NEED TO WATCH FOR POTENTIAL
HAZARDS. CURRENTLY THINK THAT WE COULD POSSIBLE URBAN FLOODING
ISSUES AS MODELS PROGGED WELL OVER 1.5 INCHES OF QPF. LATEST EC EVEN
SHOWS 2.5 INCHES OF QPF IS POSSIBLE. THE GEFS SHOW A MOISTURE FLUX
AT 850 MB BEING 4 TO 5 STANDARD DEVIATIONS AWAY...AND WITH THE
TROPICAL CONNECTION AND STRONG SOUTHERLY FLOW COULD SEE HIGHER
AMOUNTS DUE TO TOPOGRAPHY ENHANCEMENTS. RAIN FALL RECORDS MAY FALL
IF EVERYTHING FALLS INTO PLACE.

ALSO BELIEVE THAT WE MAY SEE SOME WIND ISSUES WITH THIS SYSTEM.
GUIDANCE RIGHT NOW IS SHOWING A 45 TO 55 KT JET AT 925 MB...HOWEVER
IT WILL BE HARD TO BREAK THE INVERSION WITH THE SOUTHERLY FLOW.
RIGHT NOW BELIEVE THAT WIND ADVISORIES MAY BE NEEDED BUT IF THIS
SYSTEM STRENGTHEN EVEN MORE SO A STRONGER JET IS POSSIBLE.

CONTINUED THE MENTIONED OF ISOLATED THUNDER IN THE FORECAST PER PREV
FORECASTER SUGGESTION. BELIEVE IT COULD BE POSSIBLE AS SOUTHERN NEW
ENGLAND WILL BE IN THE WARM SECTOR...WITH THE ANOMALOUS JET AND
SHOWALTERS CLOSE TO ZERO.

FRIDAY...LOW CONFIDENCE.

ONCE UPPER LEVEL LOW MOVES INTO SOUTHERN CANADA...EXPECT A RATHER
FAST UPPER W FLOW IN PLACE. MAY SEE LEFTOVER SNOW SHOWERS BUT TEMPS
WILL FALL BACK CLOSE TO SEASONAL NORMS.

&&

.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH SUNDAY/...

THROUGH 00Z...MODERATE CONFIDENCE. MVFR CIGS WILL CONTINUE TO
OVERSPREAD EASTERN NEW ENGLAND AND EVENTUALLY OVERSPREAD THE INTERIOR
THIS AFTERNOON. SCATTERED SHOWERS ACROSS PORTIONS OF EASTERN
MASSACHUSETTS THIS AFTERNOON. MAINLY SNOW SHOWERS TO THE NORTH AND
WEST OF CAPE COD CANAL...RAIN SHOWERS SOUTH AND EAST. LOCALIZED
IFR CONDITIONS POSSIBLE JUST INLAND FROM THE SOUTHEAST NEW ENGLAND
COAST...WHERE SNOW IS FALLING.

TONIGHT AND SUNDAY...MODERATE CONFIDENCE.  MVFR CONDITIONS DOMINATE
IN LOWER CLOUDS AND SCATTERED SHOWERS. LOCALIZED IFR CONDITIONS
POSSIBLE WITH THE BEST CHANCE IN SNOW SHOWERS. PRECIPITATION
AFFECTS MAINLY EASTERN NEW ENGLAND BUT STILL SOME SCATTERED
ACTIVITY ACROSS WESTERN NEW ENGLAND. MAINLY SNOW SHOWERS TO THE
NORTH AND WEST OF CAPE COD CANAL...RAIN SHOWERS SOUTH AND EAST.

KBOS TERMINAL...MODERATE CONFIDENCE IN TAF. FLURRIES AND SNOW
SHOWERS MAY AFFECT THE TERMINAL BY 21Z.

KBDL TERMINAL...MODERATE CONFIDENCE IN TAF.

OUTLOOK...SUNDAY NIGHT THROUGH WEDNESDAY...

MONDAY INTO TUESDAY...MODERATE CONFIDENCE. EXPECT MOSTLY
VFR...ISOLATED MVFR ALONG THE MASS EAST COASTLINE IN RAIN/SNOW
SHOWERS.

TUESDAY NIGHT INTO WEDNESDAY...MODERATE CONFIDENCE. CONDITIONS WILL
BE DETERIORATING AS HEAVY DOWNPOURS...ISO THUNDER AND GUSTY SOUTHERLY
WINDS MOVE INTO THE REGION BY WEDNESDAY. COULD SEE MVFR TO IFR
CONDITIONS IN CIGS AND VSBYS.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /TODAY THROUGH SUNDAY/...HIGH CONFIDENCE.

HIGH PRESSURE ACROSS QUEBEC WILL RESULT IN PERSISTENT NORTHEAST
WINDS ACROSS THE WATERS THROUGH THE WEEKEND.  WIND GUSTS UP TO 20
KNOTS WITH SEAS BETWEEN 2 AND 4 FEET ARE EXPECTED FOR MOST
WATERS...SO NO HEADLINES PLANNED. THERE IS A LOW PROBABILITY THAT A
BRIEF SURGE OF NORTHEAST WIND GUSTS NEAR 25 KNOTS WITH MARGINAL 5
FOOT SEAS COULD AFFECT OUR NORTHERN WATERS LATE TONIGHT INTO SUN
MORNING...BUT NOT CONFIDENT ENOUGH TO ISSUE ANY HEADLINES AT THIS
POINT.

OUTLOOK...SUNDAY NIGHT INTO WEDNESDAY...MODERATE TO HIGH
CONFIDENCE.

SUNDAY INTO MONDAY. CONTINUOUS NORTHEAST FLOW WILL KEEP SEAS CHOPPY.
LINGERING NORTHEAST SWELL MAY BUMP SEAS ABOVE 5FT ESP ACROSS THE
NORTHEASTERN WATERS. SCA MAY BE NEEDED...BUT LOWER CONFIDENCE.

TUESDAY INTO WEDNESDAY...NE WINDS WILL INCREASE...GUSTING TO 30 KT
TUE THEN SHIFT TO SE GUSTING TO 30-35 KT WED...HIGHEST ON THE OUTER
WATERS. SEAS BUILD UP TO 7-11 FT BY WED. GALES WILL BE NEEDED.

&&

.TIDES/COASTAL FLOODING...
HIGH ASTRONOMICAL TIDES WILL OCCUR TUESDAY THROUGH THURSDAY. BREAKING
IT DOWN...ON TUESDAY HIGH TIDE AT BOSTON WILL BE 11.6 FT. THERE WILL
BE ONSHORE FLOW DURING THIS HIGH TIDE ALLOWING FOR MINOR SPLASHOVER.
IF WIND GUSTS INCREASE THEN COULD POSSIBLE SEE MINOR COASTAL
FLOODING.

ON WEDNESDAY...WINDS WILL SWITCH TO A MORE SOUTHEASTERLY FLOW DURING
THE DAY AND INCREASE QUICKLY FROM APPROACHING SYSTEM AND DESCENT
PRESSURE FALLS. WEDNESDAY AFTERNOON HIGH TIDE IN BOSTON IS 11.7 FT
AND WITH ANY STRENGTH ON THE EASTERLY WIND FLOW WILL PUSH THE TIDE
OVER. RIGHT NOW BELIEVE MINOR COASTAL FLOODING IS POSSIBLE ALONG THE
EAST COASTLINE. HOWEVER WEDNESDAY EVENING...THE WIND GOES IN A MORE
SOUTHERLY DIRECTION AND HIGH TIDE IN PROVIDENCE WILL BE 5.2 FT. 925
MB LLJ STRENGTHENS TO 50-60 KTS WHICH COULD PUSH A DESCENT SURGE UP
ALONG THE SOUTH COAST DURING THE TIME OF HIGH TIDE. THINKING THAT
MINOR COASTAL FLOODING COULD OCCUR BUT CANNOT RULE OUT MODERATE
ALONG THE SOUTH COAST...ESP IF LLJ STRENGTHENS EVEN MORE.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...DUNTEN/RLG
NEAR TERM...FRANK/RLG
SHORT TERM...FRANK
LONG TERM...DUNTEN
AVIATION...DUNTEN/RLG
MARINE...FRANK/DUNTEN
TIDES/COASTAL FLOODING...



000
FXUS61 KBOX 201746
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
1246 PM EST SAT DEC 20 2014

.SYNOPSIS...
SCATTERED SNOW/RAIN SHOWERS WILL GRADUALLY OVERSPREAD THE REGION
FROM EAST TO WEST THIS AFTERNOON THROUGH SUN. WEAK LOW PRESSURE
WILL PASS SOUTH OF NEW ENGLAND BRINGING ANOTHER PERIOD OF PRECIP
MON NIGHT AND TUE. A MUCH STRONGER STORM PASSING WEST OF NEW
ENGLAND WILL BRING HEAVY RAINFALL...GUSTY WINDS AND COASTAL
FLOODING CONCERNS TO THE REGION WED INTO WED EVENING. DRY BUT VERY
WINDY CONDITIONS FOLLOW FOR CHRISTMAS DAY INTO FRI.

&&

.NEAR TERM /THROUGH TONIGHT/...
1245 PM UPDATE...SNOW SHOWERS CONTINUE TO AFFECT PORTIONS OF
EASTERN MASSACHUSETTS THIS AFTERNOON. THEY ARE STRUGGLING TO MOVE
WESTWARD OF CAPE ANN AND EASTERN NORFOLK COUNTY DUE TO MUCH DRIER
AIR. EVENTUALLY THE SHOWERS WILL OVERCOME THE DRIER AIR BUT EXPECT
THIS TO TAKE ANOTHER COUPLE OF HOURS...DEPENDING ON HOW QUICKLY
THE WINDS TURN TO THE NORTHEAST.

PREVIOUS DISCUSSION FOLLOWS...

INTERESTING MESOSCALE SETUP AS AN INVERTED TROUGH COMBINES WITH SOME
OCEAN ENHANCEMENT.  APPROACHING UPPER LEVEL SHORTWAVE WILL ALLOW FOR
EASTERLY FLOW JUST OFF THE GROUND.  THIS COMBINED WITH NORTHEAST
SURFACE WINDS WILL ALLOW LOW LEVEL OF THE ATMOSPHERE TO MOISTEN.
SOUNDINGS ACROSS EASTERN NEW ENGLAND BECOME SATURATED ALL THE WAY UP
TO THE -9C LAYER JUST ABOVE 850 MB.  THIS IS FAVORABLE FOR SOME
DECENT SNOW GROWTH...ITS JUST LOWER IN THE ATMOSPHERE THAN WE
TYPICALLY SEE WITH MORE SYNOPTIC SNOW EVENTS.  WHILE THIS IS NOT A
TRUE OCEAN EFFECT EVENT...DELTA T VALUES FROM THE MIXED LAYER TO THE
OCEAN ARE AROUND 15C.  THEREFORE...EXPECT SOME OCEAN ENHANCEMENT.

TIMING:

WHILE FLURRIES/LIGHT SNOW SHOWERS MAY OCCUR ACROSS FAR SOUTHEAST NEW
ENGLAND THIS MORNING.  THE MORE SUBSTANTIAL  PRECIPITATION SHOULD
OVERSPREAD PLYMOUTH COUNTY AS WELL AS THE CAPE AND ISLANDS THIS
AFTERNOON.  GIVEN EASTERLY FLOW JUST OFF THE GROUND...EXPECT SNOW
SHOWERS TO OVERSPREAD MOST OF EASTERN NEW ENGLAND THIS EVENING AS
LOW LEVELS MOISTEN.  IN FACT...SHOULD SEE AT LEAST SOME SCATTERED
SNOW SHOWERS AFFECT EVEN OUR FAR WESTERN ZONES.

PTYPE:

MAINLY SNOW FOR ALL BUT PORTIONS OF COASTAL PLYMOUTH COUNTY AND ONTO
THE CAPE/ISLANDS.  A SUBTLE COASTAL FRONT LOOKS TO SETUP ACROSS
SOUTHEAST COASTAL PLYMOUTH COUNTY.  PTYPE WILL BE SNOW TO THE
NORTHWEST OF THIS REGION...BUT ENOUGH MILD AIR SHOULD COME IN OFF
THE OCEAN FOR A CHANGE TO RAIN SHOWERS SOUTHEAST OF THIS REGION.
NOT EXPECTING THE POSITION OF THIS SUBTLE BOUNDARY TO CHANGE MUCH
THROUGH SUNDAY MORNING.

SNOW ACCUMULATIONS:

WE ARE GENERALLY LOOKING AT A COATING TO 2 INCHES OF SNOW ACROSS
MOST OF THE REGION.  THE MAIN FOCUS FOR 1 TO 2 INCHES WILL BE ACROSS
PORTIONS OF SOUTHEAST MA...AWAY FROM THE SOUTHEAST PLYMOUTH COUNTY
COAST.  ALSO...THE WORCESTER HILLS INTO NORTHWEST RHODE ISLAND MIGHT
BE ANOTHER AREA AS A RESULT OF THE SUBTLE UPSLOPE COMPONENT TO THE
WIND.  YOU CAN ACTUALLY SEE THAT IN SOME OF THE HIGH RESOLUTION
MODEL GUIDANCE.

THERE IS ONE AREA TO WATCH IN PARTICULAR...FROM NORTHWEST PLYMOUTH
COUNTY AND INTO NORFOLK COUNTY BASED ON MESOSCALE MODELS AND PATTERN
RECOGNITION.  WOULD NOT BE SURPRISED TO SEE VERY LOCALIZED 3 TO 4
INCH SNOW AMOUNTS...GIVEN SOME OCEAN ENHANCEMENT AND A LITTLE FOCUS
ON THE COASTAL FRONT.  WILL TRY TO HIGHLIGHT THIS AREA IN OUR
SNOWFALL AND PROBABILISTIC GRAPHICS.

&&

.SHORT TERM /SUNDAY/...
SCATTERED SNOW SHOWERS WILL CONTINUE DURING THE MORNING WITH
MOIST EASTERLY FLOW IN THE LOW LEVELS. AGAIN...PTYPE WILL BE SNOW
EXCEPT ACROSS SOUTHEAST PLYMOUTH COUNTY/CAPE AND ISLANDS WHERE
BOUNDARY LAYER WILL PROBABLY BE WARM ENOUGH FOR RAIN SHOWERS.
WHILE SOME LIGHT PRECIPITATION MAY LINGER INTO SUNDAY
AFTERNOON...EXPECT A DECREASE IN AREAL COVERAGE THROUGH THE
AFTERNOON AS LOW LEVEL LIFT WEAKENS. IT WILL REMAIN CLOUDY THOUGH
WITH TEMPS IN THE 30S.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
HIGHLIGHTS...

* INVERTED TROUGH WILL BRING RAIN/SNOW SHOWERS TO THE MASS EAST
  COASTLINE MONDAY INTO TUES MORNING.
* WEAK WAVE OF LOW PRESSURE MON NIGHT/TUESDAY COULD BRING WINTRY
  MIX TO INTERIOR
* ANOMALOUS SYSTEM ACROSS THE GREAT LAKES WILL BRING HEAVY
  RAIN...GUSTY WINDS AND COASTAL FLOODING CONCERNS AROUND CHRISTMAS
  EVE

OVERVIEW...

OVERALL 00Z GUIDANCE IS IN AGREEMENT SYNOPTICALLY WITH ISSUES ON
TIMING AND SMALLER SCALE FEATURES. IT REMAINS EVIDENT THAT AN
AMPLIFIED MID-UPPER LEVEL TROUGH AND PCPN FOCUSING LEAD SURFACE
LOW/FRONTAL SYSTEM WILL STEADILY PROGRESS TO THE EAST-CENTRAL U.S.
TUE AS EMBEDDED IMPULSES DIG TO THE LEE OF AN AMPLIFIED ERN
PACIFIC/WEST COAST RIDGE ALOFT. THE SUPPORTING AND INCREASINGLY
NEGATIVE-TILT TROUGH ALOFT WORKS OVER THE ERN US AND OUT THROUGH THE
NERN STATES INTO DAYS 4/5 WED/THU.  MODELS/ENSEMBLES HAVE BEEN
FAIRLY CONSISTENT ON THIS AMPLIFIED PATTERN AND THE MOST RECENT
GEFS/ECMWF ENSEMBLE GUIDANCE SHOW GOOD CORRELATION TO NEXT THURSDAY.

HIGH PRESSURE AND UPPER LEVEL RIDGE OVER THE REGION WILL BEGIN TO
EXIT BY MONDAY. AT THE SURFACE APPEARS ANOTHER INVERTED
TROUGH/ONSHORE FLOW WILL YIELD TO PRECIP ALONG THE MASS COASTLINE ON
MONDAY. ASIDE FROM THIS QUICK MESOSCALE EVENT THE MAIN FOCUS IS ON
THE LONGWAVE DIGGING TROUGH OVER THE CENTRAL CONUS WHICH WILL PUSH A
FEW SHORTWAVES THROUGH THE FLOW. FIRST ONE DEVELOPS A WEAK WAVE
MOVING TOWARDS THE REGION LATE MONDAY INTO TUESDAY. THERE IS STILL
SOME UNCERTAINTY WITH THE LOCATION/STRENGTH OF THIS SYSTEM BUT
APPEARS THAT THERE IS THE POSSIBILITY OF A SNOW/WINTRY MIX IN THE
INTERIOR. AS THIS SYSTEM DEPARTS AN ANOMALOUS LOW OVER THE GREAT
LAKES WILL DEVELOP A SECONDARY LOW JUST WEST OF SOUTHERN NEW ENGLAND
PER ENSEMBLE GUIDANCE. STILL A SOME SPREAD BUT IF THIS DOUBLE LOW
DOES DEVELOP THEN THE RAIN AND WIND ASPECT OF THE SYSTEM
INCREASES...DETAILS BELOW. STILL NEED TO WORK OUT MINOR DETAILS
WITH THIS PARTICULAR SYSTEM BUT WITH 3 TO 4 STANDARD DEVIATIONS
AWAY AND GENERAL MODEL AGREEMENT HAVE HIGH CONFIDENCE THIS SYSTEM
WILL IMPACT SOUTHERN NEW ENGLAND.

DETAILS...

SUNDAY NIGHT INTO TUESDAY...MODERATE CONFIDENCE.

HIGH PRESSURE AND UPPER LEVEL RIDGE WILL BEGIN TO MOVE OFFSHORE AS
DIGGING TROUGH BEGINS TO SET-UP OVER THE CENTRAL CONUS. APPEARS
ANOTHER MESO-SCALE INVERTED TROUGH WILL SET UP ON MONDAY AND LAST
INTO EARLY TUESDAY MORNING. GUIDANCE SHOWS THAT RAIN/SNOW SHOWERS
WILL DEVELOP ALONG THE MASS EAST COASTLINE THANKS TO ONSHORE
EASTERLY FLOW. APPEARS THE COLUMN WILL SATURATE PER BUFKIT SOUNDINGS
AND SOUTHERLY FLOW ALOFT. BOTH THE NAM AND GFS SHOW QPF MAKING IT
ONSHORE DURING THIS TIME FRAME. HOWEVER THE EC IS SLIGHTLY SLOWER
AND KEEP THE BULK OF THE PRECIP JUST OFFSHORE. ADD A CHANCE OF POPS
DUE TO THE NAM/GFS MODEL CONTINUITY.

BY LATE MONDAY NIGHT INTO TUESDAY A SOUTHERN BRANCH STORM SYSTEM
FORMS ALONG THE SE COAST AND TAKES A TRACK OFF THE MID ATLANTIC
COAST. THIS SYSTEM GETS CAUGHT UP WITH THE OVERALL LARGE SCALE
AMPLIFICATION OF THE UPPER AIR PATTERN. THERE IS DECENT WARM
ADVECTION WITH COLD AIR DAMMING ACROSS THE INTERIOR. BIGGEST
QUESTION WILL BE IS THERE ENOUGH MOISTURE FOR PRECIP DURING THIS
TIME FRAME. IF PRECIP OVERRUNS THEN COULD SEE FREEZING RAIN/DRIZZLE
ACROSS THE INTERIOR LATE MONDAY INTO TUESDAY MORNING. DURING THE DAY
ON TUESDAY...GOOD AMOUNT OF WARM AIR WILL PUSH SURFACE TEMPS ABOVE
FREEZING ALLOWING FOR ANY PRECIP TO BE MORE OF THE LIQUID VARIETY
AHEAD OF THE CHRISTMAS EVE STORM. HOWEVER GUIDANCE IS ALWAYS TOO
FAST IN SCOURING TEMPS OUT ESP ACROSS THE CT VALLEY SO WE WILL NEED
TO MONITOR THIS CLOSELY...ESP DUE TO LIGHT WINDS AND THE HIGH IN
EASTERN CANADA.

WE COULD ALSO SEE SOME MINOR COASTAL FLOODING CONCERNS ON TUESDAY. SEE
BELOW FOR MORE DETAILS.

WEDNESDAY INTO THURSDAY...HIGH CONFIDENCE IN SYSTEM LOW CONFIDENCE
ON DETAILS.

STRONG ANOMALOUS SYSTEM WILL STRENGTHEN OVER THE GREAT
LAKES...DEVELOPING A POTENTIAL SECONDARY SURFACE LOW JUST WEST OF
SOUTHERN NEW ENGLAND. STILL A LOT OF DETAILS TO WORK OUT AS THIS
SYSTEM IS STILL 5 DAYS AWAY...HOWEVER ENSEMBLES CONTINUE TO SHOW
STRONG AGREEMENT SO HAVE INCREASING CONFIDENCE THAT A POTENT STORM
WILL OCCUR. LATEST 00Z GUIDANCE SHOWS THAT MOST PRECIP WILL BE
LIQUID WITH A DEEP SUBTROPICAL CONNECTION BACK ACROSS THE GULF OF
MEXICO...PW ANOMALIES FORECAST TO RISE BETWEEN +3 TO +4. CURRENT
PWATS ARE PROGGED ABOVE 1.6 INCHES SO HAVE CONTINUED THE CATEGORICAL
POPS. TEMPERATURES WILL BE WELL ABOVE AVERAGE...IN FACT WE MAY BE
CLOSE AT BREAKING RECORD HIGH TEMPS IF TEMPS WARM TO 60F OR ABOVE ON
CHRISTMAS EVE.  AS THE SYSTEM WRAPS UP INTO CANADA...COLD AIR
ADVECTION SHOULD CIRCULATE AROUND AND BEGIN A TRANSITION FROM
SOUTHWEST TO NORTHEAST IN TURNING P-TYPE TO SNOW. HOWEVER LATEST
GUIDANCE DOES SHOW A QUICK MOVING DRY SLOT SO SNOWFALL WILL STRUGGLE
DUE TO LACK OF MOISTURE.

THIS SYSTEM IS QUITE POTENT SO WE WILL NEED TO WATCH FOR POTENTIAL
HAZARDS. CURRENTLY THINK THAT WE COULD POSSIBLE URBAN FLOODING
ISSUES AS MODELS PROGGED WELL OVER 1.5 INCHES OF QPF. LATEST EC EVEN
SHOWS 2.5 INCHES OF QPF IS POSSIBLE. THE GEFS SHOW A MOISTURE FLUX
AT 850 MB BEING 4 TO 5 STANDARD DEVIATIONS AWAY...AND WITH THE
TROPICAL CONNECTION AND STRONG SOUTHERLY FLOW COULD SEE HIGHER
AMOUNTS DUE TO TOPOGRAPHY ENHANCEMENTS. RAIN FALL RECORDS MAY FALL
IF EVERYTHING FALLS INTO PLACE.

ALSO BELIEVE THAT WE MAY SEE SOME WIND ISSUES WITH THIS SYSTEM.
GUIDANCE RIGHT NOW IS SHOWING A 45 TO 55 KT JET AT 925 MB...HOWEVER
IT WILL BE HARD TO BREAK THE INVERSION WITH THE SOUTHERLY FLOW.
RIGHT NOW BELIEVE THAT WIND ADVISORIES MAY BE NEEDED BUT IF THIS
SYSTEM STRENGTHEN EVEN MORE SO A STRONGER JET IS POSSIBLE.

CONTINUED THE MENTIONED OF ISOLATED THUNDER IN THE FORECAST PER PREV
FORECASTER SUGGESTION. BELIEVE IT COULD BE POSSIBLE AS SOUTHERN NEW
ENGLAND WILL BE IN THE WARM SECTOR...WITH THE ANOMALOUS JET AND
SHOWALTERS CLOSE TO ZERO.

FRIDAY...LOW CONFIDENCE.

ONCE UPPER LEVEL LOW MOVES INTO SOUTHERN CANADA...EXPECT A RATHER
FAST UPPER W FLOW IN PLACE. MAY SEE LEFTOVER SNOW SHOWERS BUT TEMPS
WILL FALL BACK CLOSE TO SEASONAL NORMS.

&&

.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH SUNDAY/...

THROUGH 00Z...MODERATE CONFIDENCE. MVFR CIGS WILL CONTINUE TO
OVERSPREAD EASTERN NEW ENGLAND AND EVENTUALLY OVERSPREAD THE INTERIOR
THIS AFTERNOON. SCATTERED SHOWERS ACROSS PORTIONS OF EASTERN
MASSACHUSETTS THIS AFTERNOON. MAINLY SNOW SHOWERS TO THE NORTH AND
WEST OF CAPE COD CANAL...RAIN SHOWERS SOUTH AND EAST. LOCALIZED
IFR CONDITIONS POSSIBLE JUST INLAND FROM THE SOUTHEAST NEW ENGLAND
COAST...WHERE SNOW IS FALLING.

TONIGHT AND SUNDAY...MODERATE CONFIDENCE.  MVFR CONDITIONS DOMINATE
IN LOWER CLOUDS AND SCATTERED SHOWERS. LOCALIZED IFR CONDITIONS
POSSIBLE WITH THE BEST CHANCE IN SNOW SHOWERS. PRECIPITATION
AFFECTS MAINLY EASTERN NEW ENGLAND BUT STILL SOME SCATTERED
ACTIVITY ACROSS WESTERN NEW ENGLAND. MAINLY SNOW SHOWERS TO THE
NORTH AND WEST OF CAPE COD CANAL...RAIN SHOWERS SOUTH AND EAST.

KBOS TERMINAL...MODERATE CONFIDENCE IN TAF. FLURRIES AND SNOW
SHOWERS MAY AFFECT THE TERMINAL BY 21Z.

KBDL TERMINAL...MODERATE CONFIDENCE IN TAF.

OUTLOOK...SUNDAY NIGHT THROUGH WEDNESDAY...

MONDAY INTO TUESDAY...MODERATE CONFIDENCE. EXPECT MOSTLY
VFR...ISOLATED MVFR ALONG THE MASS EAST COASTLINE IN RAIN/SNOW
SHOWERS.

TUESDAY NIGHT INTO WEDNESDAY...MODERATE CONFIDENCE. CONDITIONS WILL
BE DETERIORATING AS HEAVY DOWNPOURS...ISO THUNDER AND GUSTY SOUTHERLY
WINDS MOVE INTO THE REGION BY WEDNESDAY. COULD SEE MVFR TO IFR
CONDITIONS IN CIGS AND VSBYS.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /TODAY THROUGH SUNDAY/...HIGH CONFIDENCE.

HIGH PRESSURE ACROSS QUEBEC WILL RESULT IN PERSISTENT NORTHEAST
WINDS ACROSS THE WATERS THROUGH THE WEEKEND.  WIND GUSTS UP TO 20
KNOTS WITH SEAS BETWEEN 2 AND 4 FEET ARE EXPECTED FOR MOST
WATERS...SO NO HEADLINES PLANNED. THERE IS A LOW PROBABILITY THAT A
BRIEF SURGE OF NORTHEAST WIND GUSTS NEAR 25 KNOTS WITH MARGINAL 5
FOOT SEAS COULD AFFECT OUR NORTHERN WATERS LATE TONIGHT INTO SUN
MORNING...BUT NOT CONFIDENT ENOUGH TO ISSUE ANY HEADLINES AT THIS
POINT.

OUTLOOK...SUNDAY NIGHT INTO WEDNESDAY...MODERATE TO HIGH
CONFIDENCE.

SUNDAY INTO MONDAY. CONTINUOUS NORTHEAST FLOW WILL KEEP SEAS CHOPPY.
LINGERING NORTHEAST SWELL MAY BUMP SEAS ABOVE 5FT ESP ACROSS THE
NORTHEASTERN WATERS. SCA MAY BE NEEDED...BUT LOWER CONFIDENCE.

TUESDAY INTO WEDNESDAY...NE WINDS WILL INCREASE...GUSTING TO 30 KT
TUE THEN SHIFT TO SE GUSTING TO 30-35 KT WED...HIGHEST ON THE OUTER
WATERS. SEAS BUILD UP TO 7-11 FT BY WED. GALES WILL BE NEEDED.

&&

.TIDES/COASTAL FLOODING...
HIGH ASTRONOMICAL TIDES WILL OCCUR TUESDAY THROUGH THURSDAY. BREAKING
IT DOWN...ON TUESDAY HIGH TIDE AT BOSTON WILL BE 11.6 FT. THERE WILL
BE ONSHORE FLOW DURING THIS HIGH TIDE ALLOWING FOR MINOR SPLASHOVER.
IF WIND GUSTS INCREASE THEN COULD POSSIBLE SEE MINOR COASTAL
FLOODING.

ON WEDNESDAY...WINDS WILL SWITCH TO A MORE SOUTHEASTERLY FLOW DURING
THE DAY AND INCREASE QUICKLY FROM APPROACHING SYSTEM AND DESCENT
PRESSURE FALLS. WEDNESDAY AFTERNOON HIGH TIDE IN BOSTON IS 11.7 FT
AND WITH ANY STRENGTH ON THE EASTERLY WIND FLOW WILL PUSH THE TIDE
OVER. RIGHT NOW BELIEVE MINOR COASTAL FLOODING IS POSSIBLE ALONG THE
EAST COASTLINE. HOWEVER WEDNESDAY EVENING...THE WIND GOES IN A MORE
SOUTHERLY DIRECTION AND HIGH TIDE IN PROVIDENCE WILL BE 5.2 FT. 925
MB LLJ STRENGTHENS TO 50-60 KTS WHICH COULD PUSH A DESCENT SURGE UP
ALONG THE SOUTH COAST DURING THE TIME OF HIGH TIDE. THINKING THAT
MINOR COASTAL FLOODING COULD OCCUR BUT CANNOT RULE OUT MODERATE
ALONG THE SOUTH COAST...ESP IF LLJ STRENGTHENS EVEN MORE.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...DUNTEN/RLG
NEAR TERM...FRANK/RLG
SHORT TERM...FRANK
LONG TERM...DUNTEN
AVIATION...DUNTEN/RLG
MARINE...FRANK/DUNTEN
TIDES/COASTAL FLOODING...



000
FXUS61 KBOX 201746
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
1246 PM EST SAT DEC 20 2014

.SYNOPSIS...
SCATTERED SNOW/RAIN SHOWERS WILL GRADUALLY OVERSPREAD THE REGION
FROM EAST TO WEST THIS AFTERNOON THROUGH SUN. WEAK LOW PRESSURE
WILL PASS SOUTH OF NEW ENGLAND BRINGING ANOTHER PERIOD OF PRECIP
MON NIGHT AND TUE. A MUCH STRONGER STORM PASSING WEST OF NEW
ENGLAND WILL BRING HEAVY RAINFALL...GUSTY WINDS AND COASTAL
FLOODING CONCERNS TO THE REGION WED INTO WED EVENING. DRY BUT VERY
WINDY CONDITIONS FOLLOW FOR CHRISTMAS DAY INTO FRI.

&&

.NEAR TERM /THROUGH TONIGHT/...
1245 PM UPDATE...SNOW SHOWERS CONTINUE TO AFFECT PORTIONS OF
EASTERN MASSACHUSETTS THIS AFTERNOON. THEY ARE STRUGGLING TO MOVE
WESTWARD OF CAPE ANN AND EASTERN NORFOLK COUNTY DUE TO MUCH DRIER
AIR. EVENTUALLY THE SHOWERS WILL OVERCOME THE DRIER AIR BUT EXPECT
THIS TO TAKE ANOTHER COUPLE OF HOURS...DEPENDING ON HOW QUICKLY
THE WINDS TURN TO THE NORTHEAST.

PREVIOUS DISCUSSION FOLLOWS...

INTERESTING MESOSCALE SETUP AS AN INVERTED TROUGH COMBINES WITH SOME
OCEAN ENHANCEMENT.  APPROACHING UPPER LEVEL SHORTWAVE WILL ALLOW FOR
EASTERLY FLOW JUST OFF THE GROUND.  THIS COMBINED WITH NORTHEAST
SURFACE WINDS WILL ALLOW LOW LEVEL OF THE ATMOSPHERE TO MOISTEN.
SOUNDINGS ACROSS EASTERN NEW ENGLAND BECOME SATURATED ALL THE WAY UP
TO THE -9C LAYER JUST ABOVE 850 MB.  THIS IS FAVORABLE FOR SOME
DECENT SNOW GROWTH...ITS JUST LOWER IN THE ATMOSPHERE THAN WE
TYPICALLY SEE WITH MORE SYNOPTIC SNOW EVENTS.  WHILE THIS IS NOT A
TRUE OCEAN EFFECT EVENT...DELTA T VALUES FROM THE MIXED LAYER TO THE
OCEAN ARE AROUND 15C.  THEREFORE...EXPECT SOME OCEAN ENHANCEMENT.

TIMING:

WHILE FLURRIES/LIGHT SNOW SHOWERS MAY OCCUR ACROSS FAR SOUTHEAST NEW
ENGLAND THIS MORNING.  THE MORE SUBSTANTIAL  PRECIPITATION SHOULD
OVERSPREAD PLYMOUTH COUNTY AS WELL AS THE CAPE AND ISLANDS THIS
AFTERNOON.  GIVEN EASTERLY FLOW JUST OFF THE GROUND...EXPECT SNOW
SHOWERS TO OVERSPREAD MOST OF EASTERN NEW ENGLAND THIS EVENING AS
LOW LEVELS MOISTEN.  IN FACT...SHOULD SEE AT LEAST SOME SCATTERED
SNOW SHOWERS AFFECT EVEN OUR FAR WESTERN ZONES.

PTYPE:

MAINLY SNOW FOR ALL BUT PORTIONS OF COASTAL PLYMOUTH COUNTY AND ONTO
THE CAPE/ISLANDS.  A SUBTLE COASTAL FRONT LOOKS TO SETUP ACROSS
SOUTHEAST COASTAL PLYMOUTH COUNTY.  PTYPE WILL BE SNOW TO THE
NORTHWEST OF THIS REGION...BUT ENOUGH MILD AIR SHOULD COME IN OFF
THE OCEAN FOR A CHANGE TO RAIN SHOWERS SOUTHEAST OF THIS REGION.
NOT EXPECTING THE POSITION OF THIS SUBTLE BOUNDARY TO CHANGE MUCH
THROUGH SUNDAY MORNING.

SNOW ACCUMULATIONS:

WE ARE GENERALLY LOOKING AT A COATING TO 2 INCHES OF SNOW ACROSS
MOST OF THE REGION.  THE MAIN FOCUS FOR 1 TO 2 INCHES WILL BE ACROSS
PORTIONS OF SOUTHEAST MA...AWAY FROM THE SOUTHEAST PLYMOUTH COUNTY
COAST.  ALSO...THE WORCESTER HILLS INTO NORTHWEST RHODE ISLAND MIGHT
BE ANOTHER AREA AS A RESULT OF THE SUBTLE UPSLOPE COMPONENT TO THE
WIND.  YOU CAN ACTUALLY SEE THAT IN SOME OF THE HIGH RESOLUTION
MODEL GUIDANCE.

THERE IS ONE AREA TO WATCH IN PARTICULAR...FROM NORTHWEST PLYMOUTH
COUNTY AND INTO NORFOLK COUNTY BASED ON MESOSCALE MODELS AND PATTERN
RECOGNITION.  WOULD NOT BE SURPRISED TO SEE VERY LOCALIZED 3 TO 4
INCH SNOW AMOUNTS...GIVEN SOME OCEAN ENHANCEMENT AND A LITTLE FOCUS
ON THE COASTAL FRONT.  WILL TRY TO HIGHLIGHT THIS AREA IN OUR
SNOWFALL AND PROBABILISTIC GRAPHICS.

&&

.SHORT TERM /SUNDAY/...
SCATTERED SNOW SHOWERS WILL CONTINUE DURING THE MORNING WITH
MOIST EASTERLY FLOW IN THE LOW LEVELS. AGAIN...PTYPE WILL BE SNOW
EXCEPT ACROSS SOUTHEAST PLYMOUTH COUNTY/CAPE AND ISLANDS WHERE
BOUNDARY LAYER WILL PROBABLY BE WARM ENOUGH FOR RAIN SHOWERS.
WHILE SOME LIGHT PRECIPITATION MAY LINGER INTO SUNDAY
AFTERNOON...EXPECT A DECREASE IN AREAL COVERAGE THROUGH THE
AFTERNOON AS LOW LEVEL LIFT WEAKENS. IT WILL REMAIN CLOUDY THOUGH
WITH TEMPS IN THE 30S.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
HIGHLIGHTS...

* INVERTED TROUGH WILL BRING RAIN/SNOW SHOWERS TO THE MASS EAST
  COASTLINE MONDAY INTO TUES MORNING.
* WEAK WAVE OF LOW PRESSURE MON NIGHT/TUESDAY COULD BRING WINTRY
  MIX TO INTERIOR
* ANOMALOUS SYSTEM ACROSS THE GREAT LAKES WILL BRING HEAVY
  RAIN...GUSTY WINDS AND COASTAL FLOODING CONCERNS AROUND CHRISTMAS
  EVE

OVERVIEW...

OVERALL 00Z GUIDANCE IS IN AGREEMENT SYNOPTICALLY WITH ISSUES ON
TIMING AND SMALLER SCALE FEATURES. IT REMAINS EVIDENT THAT AN
AMPLIFIED MID-UPPER LEVEL TROUGH AND PCPN FOCUSING LEAD SURFACE
LOW/FRONTAL SYSTEM WILL STEADILY PROGRESS TO THE EAST-CENTRAL U.S.
TUE AS EMBEDDED IMPULSES DIG TO THE LEE OF AN AMPLIFIED ERN
PACIFIC/WEST COAST RIDGE ALOFT. THE SUPPORTING AND INCREASINGLY
NEGATIVE-TILT TROUGH ALOFT WORKS OVER THE ERN US AND OUT THROUGH THE
NERN STATES INTO DAYS 4/5 WED/THU.  MODELS/ENSEMBLES HAVE BEEN
FAIRLY CONSISTENT ON THIS AMPLIFIED PATTERN AND THE MOST RECENT
GEFS/ECMWF ENSEMBLE GUIDANCE SHOW GOOD CORRELATION TO NEXT THURSDAY.

HIGH PRESSURE AND UPPER LEVEL RIDGE OVER THE REGION WILL BEGIN TO
EXIT BY MONDAY. AT THE SURFACE APPEARS ANOTHER INVERTED
TROUGH/ONSHORE FLOW WILL YIELD TO PRECIP ALONG THE MASS COASTLINE ON
MONDAY. ASIDE FROM THIS QUICK MESOSCALE EVENT THE MAIN FOCUS IS ON
THE LONGWAVE DIGGING TROUGH OVER THE CENTRAL CONUS WHICH WILL PUSH A
FEW SHORTWAVES THROUGH THE FLOW. FIRST ONE DEVELOPS A WEAK WAVE
MOVING TOWARDS THE REGION LATE MONDAY INTO TUESDAY. THERE IS STILL
SOME UNCERTAINTY WITH THE LOCATION/STRENGTH OF THIS SYSTEM BUT
APPEARS THAT THERE IS THE POSSIBILITY OF A SNOW/WINTRY MIX IN THE
INTERIOR. AS THIS SYSTEM DEPARTS AN ANOMALOUS LOW OVER THE GREAT
LAKES WILL DEVELOP A SECONDARY LOW JUST WEST OF SOUTHERN NEW ENGLAND
PER ENSEMBLE GUIDANCE. STILL A SOME SPREAD BUT IF THIS DOUBLE LOW
DOES DEVELOP THEN THE RAIN AND WIND ASPECT OF THE SYSTEM
INCREASES...DETAILS BELOW. STILL NEED TO WORK OUT MINOR DETAILS
WITH THIS PARTICULAR SYSTEM BUT WITH 3 TO 4 STANDARD DEVIATIONS
AWAY AND GENERAL MODEL AGREEMENT HAVE HIGH CONFIDENCE THIS SYSTEM
WILL IMPACT SOUTHERN NEW ENGLAND.

DETAILS...

SUNDAY NIGHT INTO TUESDAY...MODERATE CONFIDENCE.

HIGH PRESSURE AND UPPER LEVEL RIDGE WILL BEGIN TO MOVE OFFSHORE AS
DIGGING TROUGH BEGINS TO SET-UP OVER THE CENTRAL CONUS. APPEARS
ANOTHER MESO-SCALE INVERTED TROUGH WILL SET UP ON MONDAY AND LAST
INTO EARLY TUESDAY MORNING. GUIDANCE SHOWS THAT RAIN/SNOW SHOWERS
WILL DEVELOP ALONG THE MASS EAST COASTLINE THANKS TO ONSHORE
EASTERLY FLOW. APPEARS THE COLUMN WILL SATURATE PER BUFKIT SOUNDINGS
AND SOUTHERLY FLOW ALOFT. BOTH THE NAM AND GFS SHOW QPF MAKING IT
ONSHORE DURING THIS TIME FRAME. HOWEVER THE EC IS SLIGHTLY SLOWER
AND KEEP THE BULK OF THE PRECIP JUST OFFSHORE. ADD A CHANCE OF POPS
DUE TO THE NAM/GFS MODEL CONTINUITY.

BY LATE MONDAY NIGHT INTO TUESDAY A SOUTHERN BRANCH STORM SYSTEM
FORMS ALONG THE SE COAST AND TAKES A TRACK OFF THE MID ATLANTIC
COAST. THIS SYSTEM GETS CAUGHT UP WITH THE OVERALL LARGE SCALE
AMPLIFICATION OF THE UPPER AIR PATTERN. THERE IS DECENT WARM
ADVECTION WITH COLD AIR DAMMING ACROSS THE INTERIOR. BIGGEST
QUESTION WILL BE IS THERE ENOUGH MOISTURE FOR PRECIP DURING THIS
TIME FRAME. IF PRECIP OVERRUNS THEN COULD SEE FREEZING RAIN/DRIZZLE
ACROSS THE INTERIOR LATE MONDAY INTO TUESDAY MORNING. DURING THE DAY
ON TUESDAY...GOOD AMOUNT OF WARM AIR WILL PUSH SURFACE TEMPS ABOVE
FREEZING ALLOWING FOR ANY PRECIP TO BE MORE OF THE LIQUID VARIETY
AHEAD OF THE CHRISTMAS EVE STORM. HOWEVER GUIDANCE IS ALWAYS TOO
FAST IN SCOURING TEMPS OUT ESP ACROSS THE CT VALLEY SO WE WILL NEED
TO MONITOR THIS CLOSELY...ESP DUE TO LIGHT WINDS AND THE HIGH IN
EASTERN CANADA.

WE COULD ALSO SEE SOME MINOR COASTAL FLOODING CONCERNS ON TUESDAY. SEE
BELOW FOR MORE DETAILS.

WEDNESDAY INTO THURSDAY...HIGH CONFIDENCE IN SYSTEM LOW CONFIDENCE
ON DETAILS.

STRONG ANOMALOUS SYSTEM WILL STRENGTHEN OVER THE GREAT
LAKES...DEVELOPING A POTENTIAL SECONDARY SURFACE LOW JUST WEST OF
SOUTHERN NEW ENGLAND. STILL A LOT OF DETAILS TO WORK OUT AS THIS
SYSTEM IS STILL 5 DAYS AWAY...HOWEVER ENSEMBLES CONTINUE TO SHOW
STRONG AGREEMENT SO HAVE INCREASING CONFIDENCE THAT A POTENT STORM
WILL OCCUR. LATEST 00Z GUIDANCE SHOWS THAT MOST PRECIP WILL BE
LIQUID WITH A DEEP SUBTROPICAL CONNECTION BACK ACROSS THE GULF OF
MEXICO...PW ANOMALIES FORECAST TO RISE BETWEEN +3 TO +4. CURRENT
PWATS ARE PROGGED ABOVE 1.6 INCHES SO HAVE CONTINUED THE CATEGORICAL
POPS. TEMPERATURES WILL BE WELL ABOVE AVERAGE...IN FACT WE MAY BE
CLOSE AT BREAKING RECORD HIGH TEMPS IF TEMPS WARM TO 60F OR ABOVE ON
CHRISTMAS EVE.  AS THE SYSTEM WRAPS UP INTO CANADA...COLD AIR
ADVECTION SHOULD CIRCULATE AROUND AND BEGIN A TRANSITION FROM
SOUTHWEST TO NORTHEAST IN TURNING P-TYPE TO SNOW. HOWEVER LATEST
GUIDANCE DOES SHOW A QUICK MOVING DRY SLOT SO SNOWFALL WILL STRUGGLE
DUE TO LACK OF MOISTURE.

THIS SYSTEM IS QUITE POTENT SO WE WILL NEED TO WATCH FOR POTENTIAL
HAZARDS. CURRENTLY THINK THAT WE COULD POSSIBLE URBAN FLOODING
ISSUES AS MODELS PROGGED WELL OVER 1.5 INCHES OF QPF. LATEST EC EVEN
SHOWS 2.5 INCHES OF QPF IS POSSIBLE. THE GEFS SHOW A MOISTURE FLUX
AT 850 MB BEING 4 TO 5 STANDARD DEVIATIONS AWAY...AND WITH THE
TROPICAL CONNECTION AND STRONG SOUTHERLY FLOW COULD SEE HIGHER
AMOUNTS DUE TO TOPOGRAPHY ENHANCEMENTS. RAIN FALL RECORDS MAY FALL
IF EVERYTHING FALLS INTO PLACE.

ALSO BELIEVE THAT WE MAY SEE SOME WIND ISSUES WITH THIS SYSTEM.
GUIDANCE RIGHT NOW IS SHOWING A 45 TO 55 KT JET AT 925 MB...HOWEVER
IT WILL BE HARD TO BREAK THE INVERSION WITH THE SOUTHERLY FLOW.
RIGHT NOW BELIEVE THAT WIND ADVISORIES MAY BE NEEDED BUT IF THIS
SYSTEM STRENGTHEN EVEN MORE SO A STRONGER JET IS POSSIBLE.

CONTINUED THE MENTIONED OF ISOLATED THUNDER IN THE FORECAST PER PREV
FORECASTER SUGGESTION. BELIEVE IT COULD BE POSSIBLE AS SOUTHERN NEW
ENGLAND WILL BE IN THE WARM SECTOR...WITH THE ANOMALOUS JET AND
SHOWALTERS CLOSE TO ZERO.

FRIDAY...LOW CONFIDENCE.

ONCE UPPER LEVEL LOW MOVES INTO SOUTHERN CANADA...EXPECT A RATHER
FAST UPPER W FLOW IN PLACE. MAY SEE LEFTOVER SNOW SHOWERS BUT TEMPS
WILL FALL BACK CLOSE TO SEASONAL NORMS.

&&

.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH SUNDAY/...

THROUGH 00Z...MODERATE CONFIDENCE. MVFR CIGS WILL CONTINUE TO
OVERSPREAD EASTERN NEW ENGLAND AND EVENTUALLY OVERSPREAD THE INTERIOR
THIS AFTERNOON. SCATTERED SHOWERS ACROSS PORTIONS OF EASTERN
MASSACHUSETTS THIS AFTERNOON. MAINLY SNOW SHOWERS TO THE NORTH AND
WEST OF CAPE COD CANAL...RAIN SHOWERS SOUTH AND EAST. LOCALIZED
IFR CONDITIONS POSSIBLE JUST INLAND FROM THE SOUTHEAST NEW ENGLAND
COAST...WHERE SNOW IS FALLING.

TONIGHT AND SUNDAY...MODERATE CONFIDENCE.  MVFR CONDITIONS DOMINATE
IN LOWER CLOUDS AND SCATTERED SHOWERS. LOCALIZED IFR CONDITIONS
POSSIBLE WITH THE BEST CHANCE IN SNOW SHOWERS. PRECIPITATION
AFFECTS MAINLY EASTERN NEW ENGLAND BUT STILL SOME SCATTERED
ACTIVITY ACROSS WESTERN NEW ENGLAND. MAINLY SNOW SHOWERS TO THE
NORTH AND WEST OF CAPE COD CANAL...RAIN SHOWERS SOUTH AND EAST.

KBOS TERMINAL...MODERATE CONFIDENCE IN TAF. FLURRIES AND SNOW
SHOWERS MAY AFFECT THE TERMINAL BY 21Z.

KBDL TERMINAL...MODERATE CONFIDENCE IN TAF.

OUTLOOK...SUNDAY NIGHT THROUGH WEDNESDAY...

MONDAY INTO TUESDAY...MODERATE CONFIDENCE. EXPECT MOSTLY
VFR...ISOLATED MVFR ALONG THE MASS EAST COASTLINE IN RAIN/SNOW
SHOWERS.

TUESDAY NIGHT INTO WEDNESDAY...MODERATE CONFIDENCE. CONDITIONS WILL
BE DETERIORATING AS HEAVY DOWNPOURS...ISO THUNDER AND GUSTY SOUTHERLY
WINDS MOVE INTO THE REGION BY WEDNESDAY. COULD SEE MVFR TO IFR
CONDITIONS IN CIGS AND VSBYS.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /TODAY THROUGH SUNDAY/...HIGH CONFIDENCE.

HIGH PRESSURE ACROSS QUEBEC WILL RESULT IN PERSISTENT NORTHEAST
WINDS ACROSS THE WATERS THROUGH THE WEEKEND.  WIND GUSTS UP TO 20
KNOTS WITH SEAS BETWEEN 2 AND 4 FEET ARE EXPECTED FOR MOST
WATERS...SO NO HEADLINES PLANNED. THERE IS A LOW PROBABILITY THAT A
BRIEF SURGE OF NORTHEAST WIND GUSTS NEAR 25 KNOTS WITH MARGINAL 5
FOOT SEAS COULD AFFECT OUR NORTHERN WATERS LATE TONIGHT INTO SUN
MORNING...BUT NOT CONFIDENT ENOUGH TO ISSUE ANY HEADLINES AT THIS
POINT.

OUTLOOK...SUNDAY NIGHT INTO WEDNESDAY...MODERATE TO HIGH
CONFIDENCE.

SUNDAY INTO MONDAY. CONTINUOUS NORTHEAST FLOW WILL KEEP SEAS CHOPPY.
LINGERING NORTHEAST SWELL MAY BUMP SEAS ABOVE 5FT ESP ACROSS THE
NORTHEASTERN WATERS. SCA MAY BE NEEDED...BUT LOWER CONFIDENCE.

TUESDAY INTO WEDNESDAY...NE WINDS WILL INCREASE...GUSTING TO 30 KT
TUE THEN SHIFT TO SE GUSTING TO 30-35 KT WED...HIGHEST ON THE OUTER
WATERS. SEAS BUILD UP TO 7-11 FT BY WED. GALES WILL BE NEEDED.

&&

.TIDES/COASTAL FLOODING...
HIGH ASTRONOMICAL TIDES WILL OCCUR TUESDAY THROUGH THURSDAY. BREAKING
IT DOWN...ON TUESDAY HIGH TIDE AT BOSTON WILL BE 11.6 FT. THERE WILL
BE ONSHORE FLOW DURING THIS HIGH TIDE ALLOWING FOR MINOR SPLASHOVER.
IF WIND GUSTS INCREASE THEN COULD POSSIBLE SEE MINOR COASTAL
FLOODING.

ON WEDNESDAY...WINDS WILL SWITCH TO A MORE SOUTHEASTERLY FLOW DURING
THE DAY AND INCREASE QUICKLY FROM APPROACHING SYSTEM AND DESCENT
PRESSURE FALLS. WEDNESDAY AFTERNOON HIGH TIDE IN BOSTON IS 11.7 FT
AND WITH ANY STRENGTH ON THE EASTERLY WIND FLOW WILL PUSH THE TIDE
OVER. RIGHT NOW BELIEVE MINOR COASTAL FLOODING IS POSSIBLE ALONG THE
EAST COASTLINE. HOWEVER WEDNESDAY EVENING...THE WIND GOES IN A MORE
SOUTHERLY DIRECTION AND HIGH TIDE IN PROVIDENCE WILL BE 5.2 FT. 925
MB LLJ STRENGTHENS TO 50-60 KTS WHICH COULD PUSH A DESCENT SURGE UP
ALONG THE SOUTH COAST DURING THE TIME OF HIGH TIDE. THINKING THAT
MINOR COASTAL FLOODING COULD OCCUR BUT CANNOT RULE OUT MODERATE
ALONG THE SOUTH COAST...ESP IF LLJ STRENGTHENS EVEN MORE.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...DUNTEN/RLG
NEAR TERM...FRANK/RLG
SHORT TERM...FRANK
LONG TERM...DUNTEN
AVIATION...DUNTEN/RLG
MARINE...FRANK/DUNTEN
TIDES/COASTAL FLOODING...



000
FXUS61 KGYX 201645
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
1145 AM EST SAT DEC 20 2014

.SYNOPSIS...
WEAK HIGH PRESSURE MOVES ACROSS THE REGION THROUGH SATURDAY. THE
HIGH BUILDS OVER NORTHERN MAINE SUNDAY...ALLOWING THE FLOW TO TURN
ONSHORE. A WEAK WEATHER DISTURBANCE MAY TRIGGER SOME FLURRIES OR
LIGHT SNOW OVER SOUTHERN REGIONS LATER SUNDAY INTO MONDAY. A WEAK
AREA OF LOW PRESSURE WILL MOVE UP THE COAST TUESDAY...WITH A MORE
SIGNIFICANT SYSTEM GRADUALLY ORGANIZING WEDNESDAY...BEFORE MOVING
OVER THE GREAT LAKES. THIS COULD BRING WINDY CONDITIONS AND THE
POTENTIAL FOR HEAVY RAIN AROUND CHRISTMAS EVE INTO EARLY CHRISTMAS
MORNING.

&&

.NEAR TERM /THROUGH TONIGHT/...
UPDATE...
CLOUDS CONTINUE TO SPREAD SOUTHWESTWARD...HOWEVER LATEST STLT
IMAGERY SHOWS PORTIONS OF THE COAST IN A BREAK AS OF MIDDAY. STRONGEST
WESTWARD PUSH OF THE LOW SC OVER THE GULF OF MAINE CONTUINUES TO
BE OVER THE NH SEACOAST. HAVE INCREASED POPS FOR THIS REGION FOR
LATER TODAY AND TONIGHT...BRINGING A LIGHT COATING OF SNOWFALL TO
THAT REGION.

MAD MINOR ADJUSTMENTS TO TODAYS WIND FORECAST...OTHERWISE
FORECAST ON TRACK.

PREV DISC...
7 AM UPDATE...SOME IMPRESSIVE RADIATIONAL COOLING
ACROSS THE NORTH THIS MORNING...WITH LOWS NOW DROPPING BELOW ZERO.
UPDATED THE LOW TEMPERATURE FORECAST BASED ON THE CURRENT OBS AND
TRENDS...AS GUIDANCE WAS OVER 10 DEGREES OFF IN MANY AREAS ACROSS
THE NORTH. STILL JUST A FEW CLOUDS HOLDING ON IN THE CT RIVER
VALLEY...OTHERWISE MOSTLY CLEAR SKIES ELSEWHERE. FORECAST IS STILL
ON TRACK FOR CLOUDS TO INCREASE THROUGH OUT THE DAY WITH LOW
STRATUS PUSHING IN FROM THE OCEAN AND FROM THE NORTH.

PREVIOUS DISCUSSION...
A WEAK SHORT WAVE IS CLEARLY VISIBLE ON
WATER VAPOR IMAGERY MOVING EAST ACROSS NY AS OF 3AM. OTHER THAN
THE CT RIVER VALLEY THE BULK OF THE CWA IS MOSTLY CLEAR. AS THE
SHORT WAVE APPROACHES WE SHOULD SEE NORTHEAST FLOW SWITCH AT 925MB
TO MORE ON SHORE EAST TO SOUTHEASTERLY FLOW. THIS WILL START TO
ADVECT LOW CLOUDS IN OFF THE OCEAN. LOW CLOUDS MOVING AROUND THE
SURFACE HIGH TO THE NORTH WILL ALSO START TO PUSH IN FROM THE
NORTHEAST. SO MOST OF THE AREA WILL GO FROM CLEAR TO MOSTLY
CLOUDY/OVERCAST SKIES BY THIS EVENING.

&&

.SHORT TERM /SUNDAY/...
LOW LEVEL ONSHORE FLOW BELOW THE RIDGE ALOFT WILL PUSH MOISTURE
INLAND. THE WEAK SHORT WAVE TROF WILL BE THE FOCUS AS IT CONTINUES
TO DRIFT EASTWARD ACROSS THE REGION LATE TONIGHT AND EARLY SUNDAY.
AN INVERTED TROUGH SETS UP AT THE SURFACE ACROSS THE FAR SOUTHERN
CWA. THIS COMBINED WITH THE SHORT WAVE SHOULD ALLOW ENOUGH
FORCING FOR ASCENT TO SATURATE UP TO 700MB. AS MENTIONED IN
YESTERDAY`S AFTERNOON FORECAST PACKAGE...THIS SETS UP A NICE
SEEDER-FEEDER PROCESS TO INCREASE THE SNOW SHOWER ACTIVITY ACROSS
SOUTHERN ZONES IN SOUTHEASTERN NEW HAMPSHIRE AND POSSIBLY COASTAL
YORK COUNTY. THERE IS GOOD MODEL AGREEMENT BETWEEN MESOSCALE AND
SYNOPTIC MODELS HINTING AT LIGHT QPF IN THESE AREAS...AND
ACCUMULATING SNOWFALL MAY BE POSSIBLE. USED A BLEND OF
NAM/GFS/ARW/NMM FOR POP AND QPF FORECAST.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
MEDIUM RANGE MODELS CONTINUE TO TRANSITION FROM A HIGHER WAVE
NUMBER TO A LOWER ONE NEXT WEEK WITH STRONG BLOCKING UPSTREAM AND
DOWNSTREAM AND MEAN TROUGH DEVELOPING ACROSS NRN TWO THIRDS OF
NOAM. THE TRANSITION PERIOD WILL MAKE FOR AN ACTIVE WX WEEK.
HOWEVER...WE LOOK TO STAY ON THE WARM SIDE OF THE TROUGH THROUGH
FRIDAY...WITH HIGHS RUNNING ABV NORMAL AND MAINLY RAIN.

BEST CHC FOR ANY ACCUMULATING SNOW IN THE EXTENDED WILL BE ALONG
THE COAST SUNDAY NIGHT INTO EARLY MONDAY AS MODELS INDICATING
DEVELOPMENT OF INVERTED TROUGH. NAM12/GFS IN FAIR AGREEMENT AS TO
TIMING AND LOCATION...DEVELOPING ALONG THE MID-COAST SUN
NIGHT...AND SHIFT WEST TOWARD THE NH AND SW ME COASTS DURING THE
DAY ON MONDAY. EURO TENDS TO HOLD THE QPF AROUND AND E OF
PENOBSCOT BAY UNTIL LATE MONDAY AND THEN SHIFTS IT EAST MONDAY
NIGHT. THE AGREEMENT BETWEEN THE NAM AND GFS THIS FAR OUT IS
INTERESTING...SINCE MODELS TEND TO NOT HANDLE THESE INVERTED
TROUGHS WELL UNTIL THEY IN THE 12-24 HOUR RANGE....BUT HAVE
GENERALLY FOLLOWED A NAM/GFS BLEND SUN NIGHT THRU MON NIGHT. QPF
WILL BE LIGHT AND SUN NIGHT IS THE BEST CHC FOR ANY ACCUMS AS
PRECIP WILL LKLY MIX WITH OR CHANGE TO RAIN DURING THE DAY
MONDAY...AND EVEN IF IT DOES STAY AS SNOW...WILL HAVE TOUGH TIME
ACCUMULATING. THE ONE THING TO WATCH FRO WITH INVERTED TROUGHS IS
IF IT LOCKS INTO ONE AREA...AND SETS UP CONVERGENT ONSHORE FLOW
SIMILAR TO COASTAL FRONT...WHICH WOULD GIVE A SPECIFIC AREA
SEVERAL INCHES WITH VERY LITTLE ELSEWHERE. FOR NOW...HOLDING ONTO
THE IDEA OF A MOVING TROUGH WITH ACCUMS OF A COATING IN MOST
SPOTS. INLAND JUST LOOKS FOR MAINLY CLOUDY SKIES IN THIS TIME
FRAMEWITH A FEW FLURRIES.

MAY SEE A LITTLE BIT OF A BREAK ON TUE AS WEAK OFFSHORE SFC LOW
EXITS AND ALLOWS SOME RIDGING TO BUILD BACK IN FROM THE NE...THEN
WE START GETTING INTO THE EFFECTS OF THE IMPRESSIVE STORM SYSTEM
THAT RAPIDLY INTENSIFIES TO OUR WEST. PRECIP MOVES IN TUE
NIGHT...WHICH WILL BEGIN AS RAIN ALONG THE COAST...WITH EARLY LOWS
IN THE MID TO UPPER 30S. INLAND...PRECIP WILL START AS SNOW...AND
TRANSITIONS TO FREEZING RAIN OR RAIN LATE TUE NIGHT...AND
EVENTUALLY TRANSITION TO RAIN WED MORNING. THE HEAVY PRECIP WILL
MAINLY FALL AS RAIN WED AFTERNOON AND WED NIGHT. GFS QPF SEEMS
HIGH...AS IT MAY BE DEALING WITH CONVECTIVE SCALING ISSUES...AND
THE 1.5-2.5" OF THE EURO SEEMS MORE REASONABLE ATTM...STRONG SE
FLOW DEVELOPS EAST OF THE OCCLUSION POINT WHICH CROSSES WRN NEW
ENGLAND WED NIGHT. WILL SEE STRONG LOW LEVEL SE JET DEVELOP ABOVE
THE INVERSION AROUND THIS TIME AS WELL...AND ALTHOUGH THE
INVERSION SHOULD PREVENT FULL MIXING...ESPECIALLY OVER
LAND...COULD SEE WIND GUSTS APPROACHING ADV LEVELS. HIGHS WED WILL
LKLY OCCUR LATE IN THE DAY WED OR WED EVE...AND WILL MAKE A RUN AT
50 IN SRN NH AND ALONG THE COAST.

SHARP BACK EDGE TO THE RAIN WILL CROSS THE REGION EARLY WED AND
RAIN SHOULD END FROM SW TO NE DURING THE MORNING AND EARLY
AFTERNOON...WITH SOME PARTIAL CLEARING POSSIBLE IN THE AFTERNOON.
GUSTY W-SW WINDS WILL DEVELOP BEHIND THE SYSTEM....BUT HIGHS WILL
STILL BE ABV NORMAL...IN THE 40S.

&&

.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
SHORT TERM...MVFR CONDITIONS WILL CONTINUE UNTIL ABOUT DAYBREAK
IN THE CT RIVER VALLEY AS LOW LEVEL MOISTURE HAS BECOME TRAPPED.
SHOULD SEE ALL AREAS RETURN TO VFR DURING THE DAY AND THEN MORE
MOISTURE WILL WORK ITS WAY INTO THE REGION AS LOW LEVEL WIND FLOW
TURNS ON SHORE. THIS WILL BRING SOME MVFR CEILING AND POSSIBLE
SOME LIGHT SNOW SHOWERS FROM SATURDAY EVENING THROUGH MONDAY.


LONG TERM...POSSIBLE PERIODS OF MVFR TO IFR AT COASTAL TERMINALS
SUN NIGHT INTO MONDAY AS INVERTED TROUGH DEVELOPS ACROSS THE GULF
OF ME. MVFR LIKELY TO HOLD TUE INTO TUE NIGHT...WITH LOWERING TO
IFR LATE TUE NIGHT AND WED IN RAIN...WITH INCREASING E-SE WINDS
LATE IN THE DAY WED.

&&

.MARINE...
SHORT TERM...WINDS AND SEAS WILL REMAIN BELOW SCA CONDITIONS THRU
SUNDAY.

LONG TERM...WATER REMAIN BLO SCA LVLS SUN NIGHT THROUGH TUE
NIGHT. STRONG LOW PRES TO THE WEST WILL SEE WINDS INCREASE TO
GALES WED AFTERNOON WITH BORDERLINE STORM FORCE WINDS POSSIBLE WED
NIGHT.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.

&&

$$




000
FXUS61 KGYX 201645
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
1145 AM EST SAT DEC 20 2014

.SYNOPSIS...
WEAK HIGH PRESSURE MOVES ACROSS THE REGION THROUGH SATURDAY. THE
HIGH BUILDS OVER NORTHERN MAINE SUNDAY...ALLOWING THE FLOW TO TURN
ONSHORE. A WEAK WEATHER DISTURBANCE MAY TRIGGER SOME FLURRIES OR
LIGHT SNOW OVER SOUTHERN REGIONS LATER SUNDAY INTO MONDAY. A WEAK
AREA OF LOW PRESSURE WILL MOVE UP THE COAST TUESDAY...WITH A MORE
SIGNIFICANT SYSTEM GRADUALLY ORGANIZING WEDNESDAY...BEFORE MOVING
OVER THE GREAT LAKES. THIS COULD BRING WINDY CONDITIONS AND THE
POTENTIAL FOR HEAVY RAIN AROUND CHRISTMAS EVE INTO EARLY CHRISTMAS
MORNING.

&&

.NEAR TERM /THROUGH TONIGHT/...
UPDATE...
CLOUDS CONTINUE TO SPREAD SOUTHWESTWARD...HOWEVER LATEST STLT
IMAGERY SHOWS PORTIONS OF THE COAST IN A BREAK AS OF MIDDAY. STRONGEST
WESTWARD PUSH OF THE LOW SC OVER THE GULF OF MAINE CONTUINUES TO
BE OVER THE NH SEACOAST. HAVE INCREASED POPS FOR THIS REGION FOR
LATER TODAY AND TONIGHT...BRINGING A LIGHT COATING OF SNOWFALL TO
THAT REGION.

MAD MINOR ADJUSTMENTS TO TODAYS WIND FORECAST...OTHERWISE
FORECAST ON TRACK.

PREV DISC...
7 AM UPDATE...SOME IMPRESSIVE RADIATIONAL COOLING
ACROSS THE NORTH THIS MORNING...WITH LOWS NOW DROPPING BELOW ZERO.
UPDATED THE LOW TEMPERATURE FORECAST BASED ON THE CURRENT OBS AND
TRENDS...AS GUIDANCE WAS OVER 10 DEGREES OFF IN MANY AREAS ACROSS
THE NORTH. STILL JUST A FEW CLOUDS HOLDING ON IN THE CT RIVER
VALLEY...OTHERWISE MOSTLY CLEAR SKIES ELSEWHERE. FORECAST IS STILL
ON TRACK FOR CLOUDS TO INCREASE THROUGH OUT THE DAY WITH LOW
STRATUS PUSHING IN FROM THE OCEAN AND FROM THE NORTH.

PREVIOUS DISCUSSION...
A WEAK SHORT WAVE IS CLEARLY VISIBLE ON
WATER VAPOR IMAGERY MOVING EAST ACROSS NY AS OF 3AM. OTHER THAN
THE CT RIVER VALLEY THE BULK OF THE CWA IS MOSTLY CLEAR. AS THE
SHORT WAVE APPROACHES WE SHOULD SEE NORTHEAST FLOW SWITCH AT 925MB
TO MORE ON SHORE EAST TO SOUTHEASTERLY FLOW. THIS WILL START TO
ADVECT LOW CLOUDS IN OFF THE OCEAN. LOW CLOUDS MOVING AROUND THE
SURFACE HIGH TO THE NORTH WILL ALSO START TO PUSH IN FROM THE
NORTHEAST. SO MOST OF THE AREA WILL GO FROM CLEAR TO MOSTLY
CLOUDY/OVERCAST SKIES BY THIS EVENING.

&&

.SHORT TERM /SUNDAY/...
LOW LEVEL ONSHORE FLOW BELOW THE RIDGE ALOFT WILL PUSH MOISTURE
INLAND. THE WEAK SHORT WAVE TROF WILL BE THE FOCUS AS IT CONTINUES
TO DRIFT EASTWARD ACROSS THE REGION LATE TONIGHT AND EARLY SUNDAY.
AN INVERTED TROUGH SETS UP AT THE SURFACE ACROSS THE FAR SOUTHERN
CWA. THIS COMBINED WITH THE SHORT WAVE SHOULD ALLOW ENOUGH
FORCING FOR ASCENT TO SATURATE UP TO 700MB. AS MENTIONED IN
YESTERDAY`S AFTERNOON FORECAST PACKAGE...THIS SETS UP A NICE
SEEDER-FEEDER PROCESS TO INCREASE THE SNOW SHOWER ACTIVITY ACROSS
SOUTHERN ZONES IN SOUTHEASTERN NEW HAMPSHIRE AND POSSIBLY COASTAL
YORK COUNTY. THERE IS GOOD MODEL AGREEMENT BETWEEN MESOSCALE AND
SYNOPTIC MODELS HINTING AT LIGHT QPF IN THESE AREAS...AND
ACCUMULATING SNOWFALL MAY BE POSSIBLE. USED A BLEND OF
NAM/GFS/ARW/NMM FOR POP AND QPF FORECAST.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
MEDIUM RANGE MODELS CONTINUE TO TRANSITION FROM A HIGHER WAVE
NUMBER TO A LOWER ONE NEXT WEEK WITH STRONG BLOCKING UPSTREAM AND
DOWNSTREAM AND MEAN TROUGH DEVELOPING ACROSS NRN TWO THIRDS OF
NOAM. THE TRANSITION PERIOD WILL MAKE FOR AN ACTIVE WX WEEK.
HOWEVER...WE LOOK TO STAY ON THE WARM SIDE OF THE TROUGH THROUGH
FRIDAY...WITH HIGHS RUNNING ABV NORMAL AND MAINLY RAIN.

BEST CHC FOR ANY ACCUMULATING SNOW IN THE EXTENDED WILL BE ALONG
THE COAST SUNDAY NIGHT INTO EARLY MONDAY AS MODELS INDICATING
DEVELOPMENT OF INVERTED TROUGH. NAM12/GFS IN FAIR AGREEMENT AS TO
TIMING AND LOCATION...DEVELOPING ALONG THE MID-COAST SUN
NIGHT...AND SHIFT WEST TOWARD THE NH AND SW ME COASTS DURING THE
DAY ON MONDAY. EURO TENDS TO HOLD THE QPF AROUND AND E OF
PENOBSCOT BAY UNTIL LATE MONDAY AND THEN SHIFTS IT EAST MONDAY
NIGHT. THE AGREEMENT BETWEEN THE NAM AND GFS THIS FAR OUT IS
INTERESTING...SINCE MODELS TEND TO NOT HANDLE THESE INVERTED
TROUGHS WELL UNTIL THEY IN THE 12-24 HOUR RANGE....BUT HAVE
GENERALLY FOLLOWED A NAM/GFS BLEND SUN NIGHT THRU MON NIGHT. QPF
WILL BE LIGHT AND SUN NIGHT IS THE BEST CHC FOR ANY ACCUMS AS
PRECIP WILL LKLY MIX WITH OR CHANGE TO RAIN DURING THE DAY
MONDAY...AND EVEN IF IT DOES STAY AS SNOW...WILL HAVE TOUGH TIME
ACCUMULATING. THE ONE THING TO WATCH FRO WITH INVERTED TROUGHS IS
IF IT LOCKS INTO ONE AREA...AND SETS UP CONVERGENT ONSHORE FLOW
SIMILAR TO COASTAL FRONT...WHICH WOULD GIVE A SPECIFIC AREA
SEVERAL INCHES WITH VERY LITTLE ELSEWHERE. FOR NOW...HOLDING ONTO
THE IDEA OF A MOVING TROUGH WITH ACCUMS OF A COATING IN MOST
SPOTS. INLAND JUST LOOKS FOR MAINLY CLOUDY SKIES IN THIS TIME
FRAMEWITH A FEW FLURRIES.

MAY SEE A LITTLE BIT OF A BREAK ON TUE AS WEAK OFFSHORE SFC LOW
EXITS AND ALLOWS SOME RIDGING TO BUILD BACK IN FROM THE NE...THEN
WE START GETTING INTO THE EFFECTS OF THE IMPRESSIVE STORM SYSTEM
THAT RAPIDLY INTENSIFIES TO OUR WEST. PRECIP MOVES IN TUE
NIGHT...WHICH WILL BEGIN AS RAIN ALONG THE COAST...WITH EARLY LOWS
IN THE MID TO UPPER 30S. INLAND...PRECIP WILL START AS SNOW...AND
TRANSITIONS TO FREEZING RAIN OR RAIN LATE TUE NIGHT...AND
EVENTUALLY TRANSITION TO RAIN WED MORNING. THE HEAVY PRECIP WILL
MAINLY FALL AS RAIN WED AFTERNOON AND WED NIGHT. GFS QPF SEEMS
HIGH...AS IT MAY BE DEALING WITH CONVECTIVE SCALING ISSUES...AND
THE 1.5-2.5" OF THE EURO SEEMS MORE REASONABLE ATTM...STRONG SE
FLOW DEVELOPS EAST OF THE OCCLUSION POINT WHICH CROSSES WRN NEW
ENGLAND WED NIGHT. WILL SEE STRONG LOW LEVEL SE JET DEVELOP ABOVE
THE INVERSION AROUND THIS TIME AS WELL...AND ALTHOUGH THE
INVERSION SHOULD PREVENT FULL MIXING...ESPECIALLY OVER
LAND...COULD SEE WIND GUSTS APPROACHING ADV LEVELS. HIGHS WED WILL
LKLY OCCUR LATE IN THE DAY WED OR WED EVE...AND WILL MAKE A RUN AT
50 IN SRN NH AND ALONG THE COAST.

SHARP BACK EDGE TO THE RAIN WILL CROSS THE REGION EARLY WED AND
RAIN SHOULD END FROM SW TO NE DURING THE MORNING AND EARLY
AFTERNOON...WITH SOME PARTIAL CLEARING POSSIBLE IN THE AFTERNOON.
GUSTY W-SW WINDS WILL DEVELOP BEHIND THE SYSTEM....BUT HIGHS WILL
STILL BE ABV NORMAL...IN THE 40S.

&&

.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
SHORT TERM...MVFR CONDITIONS WILL CONTINUE UNTIL ABOUT DAYBREAK
IN THE CT RIVER VALLEY AS LOW LEVEL MOISTURE HAS BECOME TRAPPED.
SHOULD SEE ALL AREAS RETURN TO VFR DURING THE DAY AND THEN MORE
MOISTURE WILL WORK ITS WAY INTO THE REGION AS LOW LEVEL WIND FLOW
TURNS ON SHORE. THIS WILL BRING SOME MVFR CEILING AND POSSIBLE
SOME LIGHT SNOW SHOWERS FROM SATURDAY EVENING THROUGH MONDAY.


LONG TERM...POSSIBLE PERIODS OF MVFR TO IFR AT COASTAL TERMINALS
SUN NIGHT INTO MONDAY AS INVERTED TROUGH DEVELOPS ACROSS THE GULF
OF ME. MVFR LIKELY TO HOLD TUE INTO TUE NIGHT...WITH LOWERING TO
IFR LATE TUE NIGHT AND WED IN RAIN...WITH INCREASING E-SE WINDS
LATE IN THE DAY WED.

&&

.MARINE...
SHORT TERM...WINDS AND SEAS WILL REMAIN BELOW SCA CONDITIONS THRU
SUNDAY.

LONG TERM...WATER REMAIN BLO SCA LVLS SUN NIGHT THROUGH TUE
NIGHT. STRONG LOW PRES TO THE WEST WILL SEE WINDS INCREASE TO
GALES WED AFTERNOON WITH BORDERLINE STORM FORCE WINDS POSSIBLE WED
NIGHT.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.

&&

$$




000
FXUS61 KGYX 201645
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
1145 AM EST SAT DEC 20 2014

.SYNOPSIS...
WEAK HIGH PRESSURE MOVES ACROSS THE REGION THROUGH SATURDAY. THE
HIGH BUILDS OVER NORTHERN MAINE SUNDAY...ALLOWING THE FLOW TO TURN
ONSHORE. A WEAK WEATHER DISTURBANCE MAY TRIGGER SOME FLURRIES OR
LIGHT SNOW OVER SOUTHERN REGIONS LATER SUNDAY INTO MONDAY. A WEAK
AREA OF LOW PRESSURE WILL MOVE UP THE COAST TUESDAY...WITH A MORE
SIGNIFICANT SYSTEM GRADUALLY ORGANIZING WEDNESDAY...BEFORE MOVING
OVER THE GREAT LAKES. THIS COULD BRING WINDY CONDITIONS AND THE
POTENTIAL FOR HEAVY RAIN AROUND CHRISTMAS EVE INTO EARLY CHRISTMAS
MORNING.

&&

.NEAR TERM /THROUGH TONIGHT/...
UPDATE...
CLOUDS CONTINUE TO SPREAD SOUTHWESTWARD...HOWEVER LATEST STLT
IMAGERY SHOWS PORTIONS OF THE COAST IN A BREAK AS OF MIDDAY. STRONGEST
WESTWARD PUSH OF THE LOW SC OVER THE GULF OF MAINE CONTUINUES TO
BE OVER THE NH SEACOAST. HAVE INCREASED POPS FOR THIS REGION FOR
LATER TODAY AND TONIGHT...BRINGING A LIGHT COATING OF SNOWFALL TO
THAT REGION.

MAD MINOR ADJUSTMENTS TO TODAYS WIND FORECAST...OTHERWISE
FORECAST ON TRACK.

PREV DISC...
7 AM UPDATE...SOME IMPRESSIVE RADIATIONAL COOLING
ACROSS THE NORTH THIS MORNING...WITH LOWS NOW DROPPING BELOW ZERO.
UPDATED THE LOW TEMPERATURE FORECAST BASED ON THE CURRENT OBS AND
TRENDS...AS GUIDANCE WAS OVER 10 DEGREES OFF IN MANY AREAS ACROSS
THE NORTH. STILL JUST A FEW CLOUDS HOLDING ON IN THE CT RIVER
VALLEY...OTHERWISE MOSTLY CLEAR SKIES ELSEWHERE. FORECAST IS STILL
ON TRACK FOR CLOUDS TO INCREASE THROUGH OUT THE DAY WITH LOW
STRATUS PUSHING IN FROM THE OCEAN AND FROM THE NORTH.

PREVIOUS DISCUSSION...
A WEAK SHORT WAVE IS CLEARLY VISIBLE ON
WATER VAPOR IMAGERY MOVING EAST ACROSS NY AS OF 3AM. OTHER THAN
THE CT RIVER VALLEY THE BULK OF THE CWA IS MOSTLY CLEAR. AS THE
SHORT WAVE APPROACHES WE SHOULD SEE NORTHEAST FLOW SWITCH AT 925MB
TO MORE ON SHORE EAST TO SOUTHEASTERLY FLOW. THIS WILL START TO
ADVECT LOW CLOUDS IN OFF THE OCEAN. LOW CLOUDS MOVING AROUND THE
SURFACE HIGH TO THE NORTH WILL ALSO START TO PUSH IN FROM THE
NORTHEAST. SO MOST OF THE AREA WILL GO FROM CLEAR TO MOSTLY
CLOUDY/OVERCAST SKIES BY THIS EVENING.

&&

.SHORT TERM /SUNDAY/...
LOW LEVEL ONSHORE FLOW BELOW THE RIDGE ALOFT WILL PUSH MOISTURE
INLAND. THE WEAK SHORT WAVE TROF WILL BE THE FOCUS AS IT CONTINUES
TO DRIFT EASTWARD ACROSS THE REGION LATE TONIGHT AND EARLY SUNDAY.
AN INVERTED TROUGH SETS UP AT THE SURFACE ACROSS THE FAR SOUTHERN
CWA. THIS COMBINED WITH THE SHORT WAVE SHOULD ALLOW ENOUGH
FORCING FOR ASCENT TO SATURATE UP TO 700MB. AS MENTIONED IN
YESTERDAY`S AFTERNOON FORECAST PACKAGE...THIS SETS UP A NICE
SEEDER-FEEDER PROCESS TO INCREASE THE SNOW SHOWER ACTIVITY ACROSS
SOUTHERN ZONES IN SOUTHEASTERN NEW HAMPSHIRE AND POSSIBLY COASTAL
YORK COUNTY. THERE IS GOOD MODEL AGREEMENT BETWEEN MESOSCALE AND
SYNOPTIC MODELS HINTING AT LIGHT QPF IN THESE AREAS...AND
ACCUMULATING SNOWFALL MAY BE POSSIBLE. USED A BLEND OF
NAM/GFS/ARW/NMM FOR POP AND QPF FORECAST.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
MEDIUM RANGE MODELS CONTINUE TO TRANSITION FROM A HIGHER WAVE
NUMBER TO A LOWER ONE NEXT WEEK WITH STRONG BLOCKING UPSTREAM AND
DOWNSTREAM AND MEAN TROUGH DEVELOPING ACROSS NRN TWO THIRDS OF
NOAM. THE TRANSITION PERIOD WILL MAKE FOR AN ACTIVE WX WEEK.
HOWEVER...WE LOOK TO STAY ON THE WARM SIDE OF THE TROUGH THROUGH
FRIDAY...WITH HIGHS RUNNING ABV NORMAL AND MAINLY RAIN.

BEST CHC FOR ANY ACCUMULATING SNOW IN THE EXTENDED WILL BE ALONG
THE COAST SUNDAY NIGHT INTO EARLY MONDAY AS MODELS INDICATING
DEVELOPMENT OF INVERTED TROUGH. NAM12/GFS IN FAIR AGREEMENT AS TO
TIMING AND LOCATION...DEVELOPING ALONG THE MID-COAST SUN
NIGHT...AND SHIFT WEST TOWARD THE NH AND SW ME COASTS DURING THE
DAY ON MONDAY. EURO TENDS TO HOLD THE QPF AROUND AND E OF
PENOBSCOT BAY UNTIL LATE MONDAY AND THEN SHIFTS IT EAST MONDAY
NIGHT. THE AGREEMENT BETWEEN THE NAM AND GFS THIS FAR OUT IS
INTERESTING...SINCE MODELS TEND TO NOT HANDLE THESE INVERTED
TROUGHS WELL UNTIL THEY IN THE 12-24 HOUR RANGE....BUT HAVE
GENERALLY FOLLOWED A NAM/GFS BLEND SUN NIGHT THRU MON NIGHT. QPF
WILL BE LIGHT AND SUN NIGHT IS THE BEST CHC FOR ANY ACCUMS AS
PRECIP WILL LKLY MIX WITH OR CHANGE TO RAIN DURING THE DAY
MONDAY...AND EVEN IF IT DOES STAY AS SNOW...WILL HAVE TOUGH TIME
ACCUMULATING. THE ONE THING TO WATCH FRO WITH INVERTED TROUGHS IS
IF IT LOCKS INTO ONE AREA...AND SETS UP CONVERGENT ONSHORE FLOW
SIMILAR TO COASTAL FRONT...WHICH WOULD GIVE A SPECIFIC AREA
SEVERAL INCHES WITH VERY LITTLE ELSEWHERE. FOR NOW...HOLDING ONTO
THE IDEA OF A MOVING TROUGH WITH ACCUMS OF A COATING IN MOST
SPOTS. INLAND JUST LOOKS FOR MAINLY CLOUDY SKIES IN THIS TIME
FRAMEWITH A FEW FLURRIES.

MAY SEE A LITTLE BIT OF A BREAK ON TUE AS WEAK OFFSHORE SFC LOW
EXITS AND ALLOWS SOME RIDGING TO BUILD BACK IN FROM THE NE...THEN
WE START GETTING INTO THE EFFECTS OF THE IMPRESSIVE STORM SYSTEM
THAT RAPIDLY INTENSIFIES TO OUR WEST. PRECIP MOVES IN TUE
NIGHT...WHICH WILL BEGIN AS RAIN ALONG THE COAST...WITH EARLY LOWS
IN THE MID TO UPPER 30S. INLAND...PRECIP WILL START AS SNOW...AND
TRANSITIONS TO FREEZING RAIN OR RAIN LATE TUE NIGHT...AND
EVENTUALLY TRANSITION TO RAIN WED MORNING. THE HEAVY PRECIP WILL
MAINLY FALL AS RAIN WED AFTERNOON AND WED NIGHT. GFS QPF SEEMS
HIGH...AS IT MAY BE DEALING WITH CONVECTIVE SCALING ISSUES...AND
THE 1.5-2.5" OF THE EURO SEEMS MORE REASONABLE ATTM...STRONG SE
FLOW DEVELOPS EAST OF THE OCCLUSION POINT WHICH CROSSES WRN NEW
ENGLAND WED NIGHT. WILL SEE STRONG LOW LEVEL SE JET DEVELOP ABOVE
THE INVERSION AROUND THIS TIME AS WELL...AND ALTHOUGH THE
INVERSION SHOULD PREVENT FULL MIXING...ESPECIALLY OVER
LAND...COULD SEE WIND GUSTS APPROACHING ADV LEVELS. HIGHS WED WILL
LKLY OCCUR LATE IN THE DAY WED OR WED EVE...AND WILL MAKE A RUN AT
50 IN SRN NH AND ALONG THE COAST.

SHARP BACK EDGE TO THE RAIN WILL CROSS THE REGION EARLY WED AND
RAIN SHOULD END FROM SW TO NE DURING THE MORNING AND EARLY
AFTERNOON...WITH SOME PARTIAL CLEARING POSSIBLE IN THE AFTERNOON.
GUSTY W-SW WINDS WILL DEVELOP BEHIND THE SYSTEM....BUT HIGHS WILL
STILL BE ABV NORMAL...IN THE 40S.

&&

.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
SHORT TERM...MVFR CONDITIONS WILL CONTINUE UNTIL ABOUT DAYBREAK
IN THE CT RIVER VALLEY AS LOW LEVEL MOISTURE HAS BECOME TRAPPED.
SHOULD SEE ALL AREAS RETURN TO VFR DURING THE DAY AND THEN MORE
MOISTURE WILL WORK ITS WAY INTO THE REGION AS LOW LEVEL WIND FLOW
TURNS ON SHORE. THIS WILL BRING SOME MVFR CEILING AND POSSIBLE
SOME LIGHT SNOW SHOWERS FROM SATURDAY EVENING THROUGH MONDAY.


LONG TERM...POSSIBLE PERIODS OF MVFR TO IFR AT COASTAL TERMINALS
SUN NIGHT INTO MONDAY AS INVERTED TROUGH DEVELOPS ACROSS THE GULF
OF ME. MVFR LIKELY TO HOLD TUE INTO TUE NIGHT...WITH LOWERING TO
IFR LATE TUE NIGHT AND WED IN RAIN...WITH INCREASING E-SE WINDS
LATE IN THE DAY WED.

&&

.MARINE...
SHORT TERM...WINDS AND SEAS WILL REMAIN BELOW SCA CONDITIONS THRU
SUNDAY.

LONG TERM...WATER REMAIN BLO SCA LVLS SUN NIGHT THROUGH TUE
NIGHT. STRONG LOW PRES TO THE WEST WILL SEE WINDS INCREASE TO
GALES WED AFTERNOON WITH BORDERLINE STORM FORCE WINDS POSSIBLE WED
NIGHT.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.

&&

$$




000
FXUS61 KGYX 201645
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
1145 AM EST SAT DEC 20 2014

.SYNOPSIS...
WEAK HIGH PRESSURE MOVES ACROSS THE REGION THROUGH SATURDAY. THE
HIGH BUILDS OVER NORTHERN MAINE SUNDAY...ALLOWING THE FLOW TO TURN
ONSHORE. A WEAK WEATHER DISTURBANCE MAY TRIGGER SOME FLURRIES OR
LIGHT SNOW OVER SOUTHERN REGIONS LATER SUNDAY INTO MONDAY. A WEAK
AREA OF LOW PRESSURE WILL MOVE UP THE COAST TUESDAY...WITH A MORE
SIGNIFICANT SYSTEM GRADUALLY ORGANIZING WEDNESDAY...BEFORE MOVING
OVER THE GREAT LAKES. THIS COULD BRING WINDY CONDITIONS AND THE
POTENTIAL FOR HEAVY RAIN AROUND CHRISTMAS EVE INTO EARLY CHRISTMAS
MORNING.

&&

.NEAR TERM /THROUGH TONIGHT/...
UPDATE...
CLOUDS CONTINUE TO SPREAD SOUTHWESTWARD...HOWEVER LATEST STLT
IMAGERY SHOWS PORTIONS OF THE COAST IN A BREAK AS OF MIDDAY. STRONGEST
WESTWARD PUSH OF THE LOW SC OVER THE GULF OF MAINE CONTUINUES TO
BE OVER THE NH SEACOAST. HAVE INCREASED POPS FOR THIS REGION FOR
LATER TODAY AND TONIGHT...BRINGING A LIGHT COATING OF SNOWFALL TO
THAT REGION.

MAD MINOR ADJUSTMENTS TO TODAYS WIND FORECAST...OTHERWISE
FORECAST ON TRACK.

PREV DISC...
7 AM UPDATE...SOME IMPRESSIVE RADIATIONAL COOLING
ACROSS THE NORTH THIS MORNING...WITH LOWS NOW DROPPING BELOW ZERO.
UPDATED THE LOW TEMPERATURE FORECAST BASED ON THE CURRENT OBS AND
TRENDS...AS GUIDANCE WAS OVER 10 DEGREES OFF IN MANY AREAS ACROSS
THE NORTH. STILL JUST A FEW CLOUDS HOLDING ON IN THE CT RIVER
VALLEY...OTHERWISE MOSTLY CLEAR SKIES ELSEWHERE. FORECAST IS STILL
ON TRACK FOR CLOUDS TO INCREASE THROUGH OUT THE DAY WITH LOW
STRATUS PUSHING IN FROM THE OCEAN AND FROM THE NORTH.

PREVIOUS DISCUSSION...
A WEAK SHORT WAVE IS CLEARLY VISIBLE ON
WATER VAPOR IMAGERY MOVING EAST ACROSS NY AS OF 3AM. OTHER THAN
THE CT RIVER VALLEY THE BULK OF THE CWA IS MOSTLY CLEAR. AS THE
SHORT WAVE APPROACHES WE SHOULD SEE NORTHEAST FLOW SWITCH AT 925MB
TO MORE ON SHORE EAST TO SOUTHEASTERLY FLOW. THIS WILL START TO
ADVECT LOW CLOUDS IN OFF THE OCEAN. LOW CLOUDS MOVING AROUND THE
SURFACE HIGH TO THE NORTH WILL ALSO START TO PUSH IN FROM THE
NORTHEAST. SO MOST OF THE AREA WILL GO FROM CLEAR TO MOSTLY
CLOUDY/OVERCAST SKIES BY THIS EVENING.

&&

.SHORT TERM /SUNDAY/...
LOW LEVEL ONSHORE FLOW BELOW THE RIDGE ALOFT WILL PUSH MOISTURE
INLAND. THE WEAK SHORT WAVE TROF WILL BE THE FOCUS AS IT CONTINUES
TO DRIFT EASTWARD ACROSS THE REGION LATE TONIGHT AND EARLY SUNDAY.
AN INVERTED TROUGH SETS UP AT THE SURFACE ACROSS THE FAR SOUTHERN
CWA. THIS COMBINED WITH THE SHORT WAVE SHOULD ALLOW ENOUGH
FORCING FOR ASCENT TO SATURATE UP TO 700MB. AS MENTIONED IN
YESTERDAY`S AFTERNOON FORECAST PACKAGE...THIS SETS UP A NICE
SEEDER-FEEDER PROCESS TO INCREASE THE SNOW SHOWER ACTIVITY ACROSS
SOUTHERN ZONES IN SOUTHEASTERN NEW HAMPSHIRE AND POSSIBLY COASTAL
YORK COUNTY. THERE IS GOOD MODEL AGREEMENT BETWEEN MESOSCALE AND
SYNOPTIC MODELS HINTING AT LIGHT QPF IN THESE AREAS...AND
ACCUMULATING SNOWFALL MAY BE POSSIBLE. USED A BLEND OF
NAM/GFS/ARW/NMM FOR POP AND QPF FORECAST.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
MEDIUM RANGE MODELS CONTINUE TO TRANSITION FROM A HIGHER WAVE
NUMBER TO A LOWER ONE NEXT WEEK WITH STRONG BLOCKING UPSTREAM AND
DOWNSTREAM AND MEAN TROUGH DEVELOPING ACROSS NRN TWO THIRDS OF
NOAM. THE TRANSITION PERIOD WILL MAKE FOR AN ACTIVE WX WEEK.
HOWEVER...WE LOOK TO STAY ON THE WARM SIDE OF THE TROUGH THROUGH
FRIDAY...WITH HIGHS RUNNING ABV NORMAL AND MAINLY RAIN.

BEST CHC FOR ANY ACCUMULATING SNOW IN THE EXTENDED WILL BE ALONG
THE COAST SUNDAY NIGHT INTO EARLY MONDAY AS MODELS INDICATING
DEVELOPMENT OF INVERTED TROUGH. NAM12/GFS IN FAIR AGREEMENT AS TO
TIMING AND LOCATION...DEVELOPING ALONG THE MID-COAST SUN
NIGHT...AND SHIFT WEST TOWARD THE NH AND SW ME COASTS DURING THE
DAY ON MONDAY. EURO TENDS TO HOLD THE QPF AROUND AND E OF
PENOBSCOT BAY UNTIL LATE MONDAY AND THEN SHIFTS IT EAST MONDAY
NIGHT. THE AGREEMENT BETWEEN THE NAM AND GFS THIS FAR OUT IS
INTERESTING...SINCE MODELS TEND TO NOT HANDLE THESE INVERTED
TROUGHS WELL UNTIL THEY IN THE 12-24 HOUR RANGE....BUT HAVE
GENERALLY FOLLOWED A NAM/GFS BLEND SUN NIGHT THRU MON NIGHT. QPF
WILL BE LIGHT AND SUN NIGHT IS THE BEST CHC FOR ANY ACCUMS AS
PRECIP WILL LKLY MIX WITH OR CHANGE TO RAIN DURING THE DAY
MONDAY...AND EVEN IF IT DOES STAY AS SNOW...WILL HAVE TOUGH TIME
ACCUMULATING. THE ONE THING TO WATCH FRO WITH INVERTED TROUGHS IS
IF IT LOCKS INTO ONE AREA...AND SETS UP CONVERGENT ONSHORE FLOW
SIMILAR TO COASTAL FRONT...WHICH WOULD GIVE A SPECIFIC AREA
SEVERAL INCHES WITH VERY LITTLE ELSEWHERE. FOR NOW...HOLDING ONTO
THE IDEA OF A MOVING TROUGH WITH ACCUMS OF A COATING IN MOST
SPOTS. INLAND JUST LOOKS FOR MAINLY CLOUDY SKIES IN THIS TIME
FRAMEWITH A FEW FLURRIES.

MAY SEE A LITTLE BIT OF A BREAK ON TUE AS WEAK OFFSHORE SFC LOW
EXITS AND ALLOWS SOME RIDGING TO BUILD BACK IN FROM THE NE...THEN
WE START GETTING INTO THE EFFECTS OF THE IMPRESSIVE STORM SYSTEM
THAT RAPIDLY INTENSIFIES TO OUR WEST. PRECIP MOVES IN TUE
NIGHT...WHICH WILL BEGIN AS RAIN ALONG THE COAST...WITH EARLY LOWS
IN THE MID TO UPPER 30S. INLAND...PRECIP WILL START AS SNOW...AND
TRANSITIONS TO FREEZING RAIN OR RAIN LATE TUE NIGHT...AND
EVENTUALLY TRANSITION TO RAIN WED MORNING. THE HEAVY PRECIP WILL
MAINLY FALL AS RAIN WED AFTERNOON AND WED NIGHT. GFS QPF SEEMS
HIGH...AS IT MAY BE DEALING WITH CONVECTIVE SCALING ISSUES...AND
THE 1.5-2.5" OF THE EURO SEEMS MORE REASONABLE ATTM...STRONG SE
FLOW DEVELOPS EAST OF THE OCCLUSION POINT WHICH CROSSES WRN NEW
ENGLAND WED NIGHT. WILL SEE STRONG LOW LEVEL SE JET DEVELOP ABOVE
THE INVERSION AROUND THIS TIME AS WELL...AND ALTHOUGH THE
INVERSION SHOULD PREVENT FULL MIXING...ESPECIALLY OVER
LAND...COULD SEE WIND GUSTS APPROACHING ADV LEVELS. HIGHS WED WILL
LKLY OCCUR LATE IN THE DAY WED OR WED EVE...AND WILL MAKE A RUN AT
50 IN SRN NH AND ALONG THE COAST.

SHARP BACK EDGE TO THE RAIN WILL CROSS THE REGION EARLY WED AND
RAIN SHOULD END FROM SW TO NE DURING THE MORNING AND EARLY
AFTERNOON...WITH SOME PARTIAL CLEARING POSSIBLE IN THE AFTERNOON.
GUSTY W-SW WINDS WILL DEVELOP BEHIND THE SYSTEM....BUT HIGHS WILL
STILL BE ABV NORMAL...IN THE 40S.

&&

.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
SHORT TERM...MVFR CONDITIONS WILL CONTINUE UNTIL ABOUT DAYBREAK
IN THE CT RIVER VALLEY AS LOW LEVEL MOISTURE HAS BECOME TRAPPED.
SHOULD SEE ALL AREAS RETURN TO VFR DURING THE DAY AND THEN MORE
MOISTURE WILL WORK ITS WAY INTO THE REGION AS LOW LEVEL WIND FLOW
TURNS ON SHORE. THIS WILL BRING SOME MVFR CEILING AND POSSIBLE
SOME LIGHT SNOW SHOWERS FROM SATURDAY EVENING THROUGH MONDAY.


LONG TERM...POSSIBLE PERIODS OF MVFR TO IFR AT COASTAL TERMINALS
SUN NIGHT INTO MONDAY AS INVERTED TROUGH DEVELOPS ACROSS THE GULF
OF ME. MVFR LIKELY TO HOLD TUE INTO TUE NIGHT...WITH LOWERING TO
IFR LATE TUE NIGHT AND WED IN RAIN...WITH INCREASING E-SE WINDS
LATE IN THE DAY WED.

&&

.MARINE...
SHORT TERM...WINDS AND SEAS WILL REMAIN BELOW SCA CONDITIONS THRU
SUNDAY.

LONG TERM...WATER REMAIN BLO SCA LVLS SUN NIGHT THROUGH TUE
NIGHT. STRONG LOW PRES TO THE WEST WILL SEE WINDS INCREASE TO
GALES WED AFTERNOON WITH BORDERLINE STORM FORCE WINDS POSSIBLE WED
NIGHT.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.

&&

$$




000
FXUS61 KBOX 201458
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
958 AM EST SAT DEC 20 2014

.SYNOPSIS...
SCATTERED SNOW/RAIN SHOWERS WILL GRADUALLY OVERSPREAD THE REGION
FROM EAST TO WEST LATER TODAY INTO SUN. WEAK LOW PRESSURE WILL
PASS SOUTH OF NEW ENGLAND BRINGING ANOTHER PERIOD OF PRECIP MON
NIGHT AND TUE. A MUCH STRONGER STORM PASSING WEST OF NEW ENGLAND
WILL BRING HEAVY RAINFALL...GUSTY WINDS AND COASTAL FLOODING
CONCERNS TO THE REGION WED INTO WED EVENING. DRY BUT VERY WINDY
CONDITIONS FOLLOW FOR CHRISTMAS DAY INTO FRI.

&&

.NEAR TERM /UNTIL NOON TODAY/...
10 AM UPDATE...MADE MINOR UPDATES MAINLY TO THE WINDS AND POPS.
UPDATED WINDS USING THE RAP FOR ITS HIGHER DETAIL WITH THE COASTAL
FRONT THIS AFTERNOON. SNOW SHOWERS HAVE MOVED ASHORE IN PLYMOUTH
COUNTY AS WELL AS PORTIONS OF THE CAPE AND THE EASTERN END OF CAPE
ANN. EXPECT THESE TO CONTINUE OFF AND ON THROUGH THE REMAINDER OF
THE MORNING.

SATELLITE IMAGERY SHOWS AN INTERESTING PATTERN. LOW CLOUDS MOVING
WESTWARD OFF THE OCEAN HAVE CREPT IN ALONG THE EAST COAST. THEN
ANOTHER AREA OF LOW CLOUDS HAVE MOVED NORTHWARD TOO ABOUT THE MASS
PIKE. NORTHWESTERN MASS SHOULD REMAIN MOSTLY SUNNY THROUGH THE
MORNING AND INTO THE AFTERNOON WHILE CLOUDS CONTINUE TO MOVE
WESTWARD ACROSS EASTERN MASSACHUSETTS.

&&

.SHORT TERM /NOON TODAY THROUGH 6 PM SUNDAY/...
THIS AFTERNOON AND TONIGHT...

INTERESTING MESOSCALE SETUP AS AN INVERTED TROUGH COMBINES WITH SOME
OCEAN ENHANCEMENT.  APPROACHING UPPER LEVEL SHORTWAVE WILL ALLOW FOR
EASTERLY FLOW JUST OFF THE GROUND.  THIS COMBINED WITH NORTHEAST
SURFACE WINDS WILL ALLOW LOW LEVEL OF THE ATMOSPHERE TO MOISTEN.
SOUNDINGS ACROSS EASTERN NEW ENGLAND BECOME SATURATED ALL THE WAY UP
TO THE -9C LAYER JUST ABOVE 850 MB.  THIS IS FAVORABLE FOR SOME
DECENT SNOW GROWTH...ITS JUST LOWER IN THE ATMOSPHERE THAN WE
TYPICALLY SEE WITH MORE SYNOPTIC SNOW EVENTS.  WHILE THIS IS NOT A
TRUE OCEAN EFFECT EVENT...DELTA T VALUES FROM THE MIXED LAYER TO THE
OCEAN ARE AROUND 15C.  THEREFORE...EXPECT SOME OCEAN ENHANCEMENT.

TIMING:

WHILE FLURRIES/LIGHT SNOW SHOWERS MAY OCCUR ACROSS FAR SOUTHEAST NEW
ENGLAND THIS MORNING.  THE MORE SUBSTANTIAL  PRECIPITATION SHOULD
OVERSPREAD PLYMOUTH COUNTY AS WELL AS THE CAPE AND ISLANDS THIS
AFTERNOON.  GIVEN EASTERLY FLOW JUST OFF THE GROUND...EXPECT SNOW
SHOWERS TO OVERSPREAD MOST OF EASTERN NEW ENGLAND THIS EVENING AS
LOW LEVELS MOISTEN.  IN FACT...SHOULD SEE AT LEAST SOME SCATTERED
SNOW SHOWERS AFFECT EVEN OUR FAR WESTERN ZONES.

PTYPE:

MAINLY SNOW FOR ALL BUT PORTIONS OF COASTAL PLYMOUTH COUNTY AND ONTO
THE CAPE/ISLANDS.  A SUBTLE COASTAL FRONT LOOKS TO SETUP ACROSS
SOUTHEAST COASTAL PLYMOUTH COUNTY.  PTYPE WILL BE SNOW TO THE
NORTHWEST OF THIS REGION...BUT ENOUGH MILD AIR SHOULD COME IN OFF
THE OCEAN FOR A CHANGE TO RAIN SHOWERS SOUTHEAST OF THIS REGION.
NOT EXPECTING THE POSITION OF THIS SUBTLE BOUNDARY TO CHANGE MUCH
THROUGH SUNDAY MORNING.

SNOW ACCUMULATIONS:

WE ARE GENERALLY LOOKING AT A COATING TO 2 INCHES OF SNOW ACROSS
MOST OF THE REGION.  THE MAIN FOCUS FOR 1 TO 2 INCHES WILL BE ACROSS
PORTIONS OF SOUTHEAST MA...AWAY FROM THE SOUTHEAST PLYMOUTH COUNTY
COAST.  ALSO...THE WORCESTER HILLS INTO NORTHWEST RHODE ISLAND MIGHT
BE ANOTHER AREA AS A RESULT OF THE SUBTLE UPSLOPE COMPONENT TO THE
WIND.  YOU CAN ACTUALLY SEE THAT IN SOME OF THE HIGH RESOLUTION
MODEL GUIDANCE.

THERE IS ONE AREA TO WATCH IN PARTICULAR...FROM NORTHWEST PLYMOUTH
COUNTY AND INTO NORFOLK COUNTY BASED ON MESOSCALE MODELS AND PATTERN
RECOGNITION.  WOULD NOT BE SURPRISED TO SEE VERY LOCALIZED 3 TO 4
INCH SNOW AMOUNTS...GIVEN SOME OCEAN ENHANCEMENT AND A LITTLE FOCUS
ON THE COASTAL FRONT.  WILL TRY TO HIGHLIGHT THIS AREA IN OUR
SNOWFALL AND PROBABILISTIC  GRAPHICS.

SUNDAY...

SCATTERED SNOW SHOWERS WILL CONTINUE DURING THE MORNING WITH MOIST
EASTERLY FLOW IN THE LOW LEVELS. AGAIN...PTYPE WILL BE SNOW EXCEPT
ACROSS SOUTHEAST PLYMOUTH COUNTY/CAPE AND ISLANDS WHERE BOUNDARY
LAYER WILL PROBABLY BE WARM ENOUGH FOR RAIN SHOWERS.  WHILE SOME
LIGHT PRECIPITATION MAY LINGER INTO SUNDAY AFTERNOON...EXPECT A
DECREASE IN AREAL COVERAGE THROUGH THE AFTERNOON AS LOW LEVEL LIFT
WEAKENS.  IT WILL REMAIN CLOUDY THOUGH WITH TEMPS IN THE 30S.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
HIGHLIGHTS...

* INVERTED TROUGH WILL BRING RAIN/SNOW SHOWERS TO THE MASS EAST
  COASTLINE MONDAY INTO TUES MORNING.
* WEAK WAVE OF LOW PRESSURE MON NIGHT/TUESDAY COULD BRING WINTRY
  MIX TO INTERIOR
* ANOMALOUS SYSTEM ACROSS THE GREAT LAKES WILL BRING HEAVY
  RAIN...GUSTY WINDS AND COASTAL FLOODING CONCERNS AROUND CHRISTMAS
  EVE

OVERVIEW...

OVERALL 00Z GUIDANCE IS IN AGREEMENT SYNOPTICALLY WITH ISSUES ON
TIMING AND SMALLER SCALE FEATURES. IT REMAINS EVIDENT THAT AN
AMPLIFIED MID-UPPER LEVEL TROUGH AND PCPN FOCUSING LEAD SURFACE
LOW/FRONTAL SYSTEM WILL STEADILY PROGRESS TO THE EAST-CENTRAL U.S.
TUE AS EMBEDDED IMPULSES DIG TO THE LEE OF AN AMPLIFIED ERN
PACIFIC/WEST COAST RIDGE ALOFT. THE SUPPORTING AND INCREASINGLY
NEGATIVE-TILT TROUGH ALOFT WORKS OVER THE ERN US AND OUT THROUGH THE
NERN STATES INTO DAYS 4/5 WED/THU.  MODELS/ENSEMBLES HAVE BEEN
FAIRLY CONSISTENT ON THIS AMPLIFIED PATTERN AND THE MOST RECENT
GEFS/ECMWF ENSEMBLE GUIDANCE SHOW GOOD CORRELATION TO NEXT THURSDAY.

HIGH PRESSURE AND UPPER LEVEL RIDGE OVER THE REGION WILL BEGIN TO
EXIT BY MONDAY. AT THE SURFACE APPEARS ANOTHER INVERTED
TROUGH/ONSHORE FLOW WILL YIELD TO PRECIP ALONG THE MASS COASTLINE ON
MONDAY. ASIDE FROM THIS QUICK MESOSCALE EVENT THE MAIN FOCUS IS ON
THE LONGWAVE DIGGING TROUGH OVER THE CENTRAL CONUS WHICH WILL PUSH A
FEW SHORTWAVES THROUGH THE FLOW. FIRST ONE DEVELOPS A WEAK WAVE
MOVING TOWARDS THE REGION LATE MONDAY INTO TUESDAY. THERE IS STILL
SOME UNCERTAINTY WITH THE LOCATION/STRENGTH OF THIS SYSTEM BUT
APPEARS THAT THERE IS THE POSSIBILITY OF A SNOW/WINTRY MIX IN THE
INTERIOR. AS THIS SYSTEM DEPARTS AN ANOMALOUS LOW OVER THE GREAT
LAKES WILL DEVELOP A SECONDARY LOW JUST WEST OF SOUTHERN NEW ENGLAND
     PER ENSEMBLE GUIDANCE. STILL A SOME SPREAD BUT IF THIS DOUBLE LOW
DOES DEVELOP THEN THE RAIN AND WIND ASPECT OF THE SYSTEM
INCREASES...DETAILS BELOW. STILL NEED TO WORK OUT MINOR DETAILS WITH
THIS PARTICULAR SYSTEM BUT WITH 3 TO 4 STANDARD DEVIATIONS AWAY AND
GENERAL MODEL AGREEMENT HAVE HIGH CONFIDENCE THIS SYSTEM WILL IMPACT
SOUTHERN NEW ENGLAND.

DETAILS...

SUNDAY NIGHT INTO TUESDAY...MODERATE CONFIDENCE.

HIGH PRESSURE AND UPPER LEVEL RIDGE WILL BEGIN TO MOVE OFFSHORE AS
DIGGING TROUGH BEGINS TO SET-UP OVER THE CENTRAL CONUS. APPEARS
ANOTHER MESO-SCALE INVERTED TROUGH WILL SET UP ON MONDAY AND LAST
INTO EARLY TUESDAY MORNING. GUIDANCE SHOWS THAT RAIN/SNOW SHOWERS
WILL DEVELOP ALONG THE MASS EAST COASTLINE THANKS TO ONSHORE
EASTERLY FLOW. APPEARS THE COLUMN WILL SATURATE PER BUFKIT SOUNDINGS
AND SOUTHERLY FLOW ALOFT. BOTH THE NAM AND GFS SHOW QPF MAKING IT
ONSHORE DURING THIS TIME FRAME. HOWEVER THE EC IS SLIGHTLY SLOWER
AND KEEP THE BULK OF THE PRECIP JUST OFFSHORE. ADD A CHANCE OF POPS
DUE TO THE NAM/GFS MODEL CONTINUITY.

BY LATE MONDAY NIGHT INTO TUESDAY A SOUTHERN BRANCH STORM SYSTEM
FORMS ALONG THE SE COAST AND TAKES A TRACK OFF THE MID ATLANTIC
COAST. THIS SYSTEM GETS CAUGHT UP WITH THE OVERALL LARGE SCALE
AMPLIFICATION OF THE UPPER AIR PATTERN. THERE IS DECENT WARM
ADVECTION WITH COLD AIR DAMMING ACROSS THE INTERIOR. BIGGEST
QUESTION WILL BE IS THERE ENOUGH MOISTURE FOR PRECIP DURING THIS
TIME FRAME. IF PRECIP OVERRUNS THEN COULD SEE FREEZING RAIN/DRIZZLE
ACROSS THE INTERIOR LATE MONDAY INTO TUESDAY MORNING. DURING THE DAY
ON TUESDAY...GOOD AMOUNT OF WARM AIR WILL PUSH SURFACE TEMPS ABOVE
FREEZING ALLOWING FOR ANY PRECIP TO BE MORE OF THE LIQUID VARIETY
AHEAD OF THE CHRISTMAS EVE STORM. HOWEVER GUIDANCE IS ALWAYS TOO
FAST IN SCOURING TEMPS OUT ESP ACROSS THE CT VALLEY SO WE WILL NEED
TO MONITOR THIS CLOSELY...ESP DUE TO LIGHT WINDS AND THE HIGH IN
EASTERN CANADA.

WE COULD ALSO SEE SOME MINOR COASTAL FLOODING CONCERNS ON TUESDAY. SEE
BELOW FOR MORE DETAILS.

WEDNESDAY INTO THURSDAY...HIGH CONFIDENCE IN SYSTEM LOW CONFIDENCE
ON DETAILS.

STRONG ANOMALOUS SYSTEM WILL STRENGTHEN OVER THE GREAT
LAKES...DEVELOPING A POTENTIAL SECONDARY SURFACE LOW JUST WEST OF
SOUTHERN NEW ENGLAND. STILL A LOT OF DETAILS TO WORK OUT AS THIS
SYSTEM IS STILL 5 DAYS AWAY...HOWEVER ENSEMBLES CONTINUE TO SHOW
STRONG AGREEMENT SO HAVE INCREASING CONFIDENCE THAT A POTENT STORM
WILL OCCUR. LATEST 00Z GUIDANCE SHOWS THAT MOST PRECIP WILL BE
LIQUID WITH A DEEP SUBTROPICAL CONNECTION BACK ACROSS THE GULF OF
MEXICO...PW ANOMALIES FORECAST TO RISE BETWEEN +3 TO +4. CURRENT
PWATS ARE PROGGED ABOVE 1.6 INCHES SO HAVE CONTINUED THE CATEGORICAL
POPS. TEMPERATURES WILL BE WELL ABOVE AVERAGE...IN FACT WE MAY BE
CLOSE AT BREAKING RECORD HIGH TEMPS IF TEMPS WARM TO 60F OR ABOVE ON
CHRISTMAS EVE.  AS THE SYSTEM WRAPS UP INTO CANADA...COLD AIR
ADVECTION SHOULD CIRCULATE AROUND AND BEGIN A TRANSITION FROM
SOUTHWEST TO NORTHEAST IN TURNING P-TYPE TO SNOW. HOWEVER LATEST
GUIDANCE DOES SHOW A QUICK MOVING DRY SLOT SO SNOWFALL WILL STRUGGLE
DUE TO LACK OF MOISTURE.

THIS SYSTEM IS QUITE POTENT SO WE WILL NEED TO WATCH FOR POTENTIAL
HAZARDS. CURRENTLY THINK THAT WE COULD POSSIBLE URBAN FLOODING
ISSUES AS MODELS PROGGED WELL OVER 1.5 INCHES OF QPF. LATEST EC EVEN
SHOWS 2.5 INCHES OF QPF IS POSSIBLE. THE GEFS SHOW A MOISTURE FLUX
AT 850 MB BEING 4 TO 5 STANDARD DEVIATIONS AWAY...AND WITH THE
TROPICAL CONNECTION AND STRONG SOUTHERLY FLOW COULD SEE HIGHER
AMOUNTS DUE TO TOPOGRAPHY ENHANCEMENTS. RAIN FALL RECORDS MAY FALL
IF EVERYTHING FALLS INTO PLACE.

ALSO BELIEVE THAT WE MAY SEE SOME WIND ISSUES WITH THIS SYSTEM.
GUIDANCE RIGHT NOW IS SHOWING A 45 TO 55 KT JET AT 925 MB...HOWEVER
IT WILL BE HARD TO BREAK THE INVERSION WITH THE SOUTHERLY FLOW.
RIGHT NOW BELIEVE THAT WIND ADVISORIES MAY BE NEEDED BUT IF THIS
SYSTEM STRENGTHEN EVEN MORE SO A STRONGER JET IS POSSIBLE.

CONTINUED THE MENTIONED OF ISOLATED THUNDER IN THE FORECAST PER PREV
FORECASTER SUGGESTION. BELIEVE IT COULD BE POSSIBLE AS SOUTHERN NEW
ENGLAND WILL BE IN THE WARM SECTOR...WITH THE ANOMALOUS JET AND
SHOWALTERS CLOSE TO ZERO.

FRIDAY...LOW CONFIDENCE.

ONCE UPPER LEVEL LOW MOVES INTO SOUTHERN CANADA...EXPECT A RATHER
FAST UPPER W FLOW IN PLACE. MAY SEE LEFTOVER SNOW SHOWERS BUT TEMPS
WILL FALL BACK CLOSE TO SEASONAL NORMS.

&&

.AVIATION /15Z SATURDAY THROUGH WEDNESDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH SUNDAY/...

700 AM UPDATE...

TODAY...MODERATE CONFIDENCE.  MVFR CIGS WILL CONTINUE TO OVERSPREAD
EASTERN NEW ENGLAND THIS MORNING AND EVENTUALLY INTO THE INTERIOR
THIS AFTERNOON.  SCATTERED PRECIPITATION WILL OVERSPREAD
SOUTHEAST MA/CAPE/ISLANDS THIS AFTERNOON.  PTYPE MAINLY SNOW SHOWERS
NORTHWEST OF THE SOUTHEAST PLYMOUTH COUNTY COAST AND RAIN SHOWERS
SOUTHEAST OF THAT REGION. LOCALIZED IFR CONDITIONS POSSIBLE JUST
INLAND FROM THE SOUTHEAST NEW ENGLAND COAST...WHERE PTYPE IS SNOW.

TONIGHT AND SUNDAY...MODERATE CONFIDENCE.  MVFR CONDITIONS DOMINATE
IN LOWER CLOUDS AND SCATTERED PRECIPITATION.  LOCALIZED IFR
CONDITIONS POSSIBLE WITH THE BEST CHANCE IN SNOW SHOWERS.
PRECIPITATION AFFECTS MAINLY EASTERN NEW ENGLAND BUT STILL SOME
SCATTERED ACTIVITY ACROSS WESTERN NEW ENGLAND. PTYPE MAINLY SNOW
SHOWERS NORTHWEST OF THE SOUTHEAST PLYMOUTH COUNTY COAST...WITH RAIN
SHOWERS SOUTHEAST OF THAT REGION.

KBOS TERMINAL...MODERATE CONFIDENCE IN TAF.  SNOW SHOWERS MAY ARRIVE
TOWARDS 00Z THIS EVENING.

KBDL TERMINAL...MODERATE CONFIDENCE IN TAF.

OUTLOOK...SUNDAY NIGHT THROUGH WEDNESDAY...

MONDAY INTO TUESDAY...MODERATE CONFIDENCE. EXPECT MOSTLY
VFR...ISOLATED MVFR ALONG THE MASS EAST COASTLINE IN RAIN/SNOW
SHOWERS.

TUESDAY NIGHT INTO WEDNESDAY...MODERATE CONFIDENCE. CONDITIONS WILL
BE DETERIORATING AS HEAVY DOWNPOURS...ISO THUNDER AND GUSTY SOUTHERLY
WINDS MOVE INTO THE REGION BY WEDNESDAY. COULD SEE MVFR TO IFR
CONDITIONS IN CIGS AND VSBYS.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /TODAY THROUGH SUNDAY/...HIGH CONFIDENCE.

HIGH PRESSURE ACROSS QUEBEC WILL RESULT IN PERSISTENT NORTHEAST
WINDS ACROSS THE WATERS THROUGH THE WEEKEND.  WIND GUSTS UP TO 20
KNOTS WITH SEAS BETWEEN 2 AND 4 FEET ARE EXPECTED FOR MOST
WATERS...SO NO HEADLINES PLANNED. THERE IS A LOW PROBABILITY THAT A
BRIEF SURGE OF NORTHEAST WIND GUSTS NEAR 25 KNOTS WITH MARGINAL 5
FOOT SEAS COULD AFFECT OUR NORTHERN WATERS LATE TONIGHT INTO SUN
MORNING...BUT NOT CONFIDENT ENOUGH TO ISSUE ANY HEADLINES AT THIS
POINT.

OUTLOOK...SUNDAY NIGHT INTO WEDNESDAY...MODERATE TO HIGH
CONFIDENCE.

SUNDAY INTO MONDAY. CONTINUOUS NORTHEAST FLOW WILL KEEP SEAS CHOPPY.
LINGERING NORTHEAST SWELL MAY BUMP SEAS ABOVE 5FT ESP ACROSS THE
NORTHEASTERN WATERS. SCA MAY BE NEEDED...BUT LOWER CONFIDENCE.

TUESDAY INTO WEDNESDAY...NE WINDS WILL INCREASE...GUSTING TO 30 KT
TUE THEN SHIFT TO SE GUSTING TO 30-35 KT WED...HIGHEST ON THE OUTER
WATERS. SEAS BUILD UP TO 7-11 FT BY WED. GALES WILL BE NEEDED.

&&

.TIDES/COASTAL FLOODING...
HIGH ASTRONOMICAL TIDES WILL OCCUR TUESDAY THROUGH THURSDAY. BREAKING
IT DOWN...ON TUESDAY HIGH TIDE AT BOSTON WILL BE 11.6 FT. THERE WILL
BE ONSHORE FLOW DURING THIS HIGH TIDE ALLOWING FOR MINOR SPLASHOVER.
IF WIND GUSTS INCREASE THEN COULD POSSIBLE SEE MINOR COASTAL
FLOODING.

ON WEDNESDAY...WINDS WILL SWITCH TO A MORE SOUTHEASTERLY FLOW DURING
THE DAY AND INCREASE QUICKLY FROM APPROACHING SYSTEM AND DESCENT
PRESSURE FALLS. WEDNESDAY AFTERNOON HIGH TIDE IN BOSTON IS 11.7 FT
AND WITH ANY STRENGTH ON THE EASTERLY WIND FLOW WILL PUSH THE TIDE
OVER. RIGHT NOW BELIEVE MINOR COASTAL FLOODING IS POSSIBLE ALONG THE
EAST COASTLINE. HOWEVER WEDNESDAY EVENING...THE WIND GOES IN A MORE
SOUTHERLY DIRECTION AND HIGH TIDE IN PROVIDENCE WILL BE 5.2 FT. 925
MB LLJ STRENGTHENS TO 50-60 KTS WHICH COULD PUSH A DESCENT SURGE UP
ALONG THE SOUTH COAST DURING THE TIME OF HIGH TIDE. THINKING THAT
MINOR COASTAL FLOODING COULD OCCUR BUT CANNOT RULE OUT MODERATE
ALONG THE SOUTH COAST...ESP IF LLJ STRENGTHENS EVEN MORE.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...FRANK/DUNTEN
NEAR TERM...FRANK/DUNTEN/RLG
SHORT TERM...FRANK
LONG TERM...DUNTEN
AVIATION...FRANK/DUNTEN
MARINE...FRANK/DUNTEN
TIDES/COASTAL FLOODING...



000
FXUS61 KBOX 201458
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
958 AM EST SAT DEC 20 2014

.SYNOPSIS...
SCATTERED SNOW/RAIN SHOWERS WILL GRADUALLY OVERSPREAD THE REGION
FROM EAST TO WEST LATER TODAY INTO SUN. WEAK LOW PRESSURE WILL
PASS SOUTH OF NEW ENGLAND BRINGING ANOTHER PERIOD OF PRECIP MON
NIGHT AND TUE. A MUCH STRONGER STORM PASSING WEST OF NEW ENGLAND
WILL BRING HEAVY RAINFALL...GUSTY WINDS AND COASTAL FLOODING
CONCERNS TO THE REGION WED INTO WED EVENING. DRY BUT VERY WINDY
CONDITIONS FOLLOW FOR CHRISTMAS DAY INTO FRI.

&&

.NEAR TERM /UNTIL NOON TODAY/...
10 AM UPDATE...MADE MINOR UPDATES MAINLY TO THE WINDS AND POPS.
UPDATED WINDS USING THE RAP FOR ITS HIGHER DETAIL WITH THE COASTAL
FRONT THIS AFTERNOON. SNOW SHOWERS HAVE MOVED ASHORE IN PLYMOUTH
COUNTY AS WELL AS PORTIONS OF THE CAPE AND THE EASTERN END OF CAPE
ANN. EXPECT THESE TO CONTINUE OFF AND ON THROUGH THE REMAINDER OF
THE MORNING.

SATELLITE IMAGERY SHOWS AN INTERESTING PATTERN. LOW CLOUDS MOVING
WESTWARD OFF THE OCEAN HAVE CREPT IN ALONG THE EAST COAST. THEN
ANOTHER AREA OF LOW CLOUDS HAVE MOVED NORTHWARD TOO ABOUT THE MASS
PIKE. NORTHWESTERN MASS SHOULD REMAIN MOSTLY SUNNY THROUGH THE
MORNING AND INTO THE AFTERNOON WHILE CLOUDS CONTINUE TO MOVE
WESTWARD ACROSS EASTERN MASSACHUSETTS.

&&

.SHORT TERM /NOON TODAY THROUGH 6 PM SUNDAY/...
THIS AFTERNOON AND TONIGHT...

INTERESTING MESOSCALE SETUP AS AN INVERTED TROUGH COMBINES WITH SOME
OCEAN ENHANCEMENT.  APPROACHING UPPER LEVEL SHORTWAVE WILL ALLOW FOR
EASTERLY FLOW JUST OFF THE GROUND.  THIS COMBINED WITH NORTHEAST
SURFACE WINDS WILL ALLOW LOW LEVEL OF THE ATMOSPHERE TO MOISTEN.
SOUNDINGS ACROSS EASTERN NEW ENGLAND BECOME SATURATED ALL THE WAY UP
TO THE -9C LAYER JUST ABOVE 850 MB.  THIS IS FAVORABLE FOR SOME
DECENT SNOW GROWTH...ITS JUST LOWER IN THE ATMOSPHERE THAN WE
TYPICALLY SEE WITH MORE SYNOPTIC SNOW EVENTS.  WHILE THIS IS NOT A
TRUE OCEAN EFFECT EVENT...DELTA T VALUES FROM THE MIXED LAYER TO THE
OCEAN ARE AROUND 15C.  THEREFORE...EXPECT SOME OCEAN ENHANCEMENT.

TIMING:

WHILE FLURRIES/LIGHT SNOW SHOWERS MAY OCCUR ACROSS FAR SOUTHEAST NEW
ENGLAND THIS MORNING.  THE MORE SUBSTANTIAL  PRECIPITATION SHOULD
OVERSPREAD PLYMOUTH COUNTY AS WELL AS THE CAPE AND ISLANDS THIS
AFTERNOON.  GIVEN EASTERLY FLOW JUST OFF THE GROUND...EXPECT SNOW
SHOWERS TO OVERSPREAD MOST OF EASTERN NEW ENGLAND THIS EVENING AS
LOW LEVELS MOISTEN.  IN FACT...SHOULD SEE AT LEAST SOME SCATTERED
SNOW SHOWERS AFFECT EVEN OUR FAR WESTERN ZONES.

PTYPE:

MAINLY SNOW FOR ALL BUT PORTIONS OF COASTAL PLYMOUTH COUNTY AND ONTO
THE CAPE/ISLANDS.  A SUBTLE COASTAL FRONT LOOKS TO SETUP ACROSS
SOUTHEAST COASTAL PLYMOUTH COUNTY.  PTYPE WILL BE SNOW TO THE
NORTHWEST OF THIS REGION...BUT ENOUGH MILD AIR SHOULD COME IN OFF
THE OCEAN FOR A CHANGE TO RAIN SHOWERS SOUTHEAST OF THIS REGION.
NOT EXPECTING THE POSITION OF THIS SUBTLE BOUNDARY TO CHANGE MUCH
THROUGH SUNDAY MORNING.

SNOW ACCUMULATIONS:

WE ARE GENERALLY LOOKING AT A COATING TO 2 INCHES OF SNOW ACROSS
MOST OF THE REGION.  THE MAIN FOCUS FOR 1 TO 2 INCHES WILL BE ACROSS
PORTIONS OF SOUTHEAST MA...AWAY FROM THE SOUTHEAST PLYMOUTH COUNTY
COAST.  ALSO...THE WORCESTER HILLS INTO NORTHWEST RHODE ISLAND MIGHT
BE ANOTHER AREA AS A RESULT OF THE SUBTLE UPSLOPE COMPONENT TO THE
WIND.  YOU CAN ACTUALLY SEE THAT IN SOME OF THE HIGH RESOLUTION
MODEL GUIDANCE.

THERE IS ONE AREA TO WATCH IN PARTICULAR...FROM NORTHWEST PLYMOUTH
COUNTY AND INTO NORFOLK COUNTY BASED ON MESOSCALE MODELS AND PATTERN
RECOGNITION.  WOULD NOT BE SURPRISED TO SEE VERY LOCALIZED 3 TO 4
INCH SNOW AMOUNTS...GIVEN SOME OCEAN ENHANCEMENT AND A LITTLE FOCUS
ON THE COASTAL FRONT.  WILL TRY TO HIGHLIGHT THIS AREA IN OUR
SNOWFALL AND PROBABILISTIC  GRAPHICS.

SUNDAY...

SCATTERED SNOW SHOWERS WILL CONTINUE DURING THE MORNING WITH MOIST
EASTERLY FLOW IN THE LOW LEVELS. AGAIN...PTYPE WILL BE SNOW EXCEPT
ACROSS SOUTHEAST PLYMOUTH COUNTY/CAPE AND ISLANDS WHERE BOUNDARY
LAYER WILL PROBABLY BE WARM ENOUGH FOR RAIN SHOWERS.  WHILE SOME
LIGHT PRECIPITATION MAY LINGER INTO SUNDAY AFTERNOON...EXPECT A
DECREASE IN AREAL COVERAGE THROUGH THE AFTERNOON AS LOW LEVEL LIFT
WEAKENS.  IT WILL REMAIN CLOUDY THOUGH WITH TEMPS IN THE 30S.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
HIGHLIGHTS...

* INVERTED TROUGH WILL BRING RAIN/SNOW SHOWERS TO THE MASS EAST
  COASTLINE MONDAY INTO TUES MORNING.
* WEAK WAVE OF LOW PRESSURE MON NIGHT/TUESDAY COULD BRING WINTRY
  MIX TO INTERIOR
* ANOMALOUS SYSTEM ACROSS THE GREAT LAKES WILL BRING HEAVY
  RAIN...GUSTY WINDS AND COASTAL FLOODING CONCERNS AROUND CHRISTMAS
  EVE

OVERVIEW...

OVERALL 00Z GUIDANCE IS IN AGREEMENT SYNOPTICALLY WITH ISSUES ON
TIMING AND SMALLER SCALE FEATURES. IT REMAINS EVIDENT THAT AN
AMPLIFIED MID-UPPER LEVEL TROUGH AND PCPN FOCUSING LEAD SURFACE
LOW/FRONTAL SYSTEM WILL STEADILY PROGRESS TO THE EAST-CENTRAL U.S.
TUE AS EMBEDDED IMPULSES DIG TO THE LEE OF AN AMPLIFIED ERN
PACIFIC/WEST COAST RIDGE ALOFT. THE SUPPORTING AND INCREASINGLY
NEGATIVE-TILT TROUGH ALOFT WORKS OVER THE ERN US AND OUT THROUGH THE
NERN STATES INTO DAYS 4/5 WED/THU.  MODELS/ENSEMBLES HAVE BEEN
FAIRLY CONSISTENT ON THIS AMPLIFIED PATTERN AND THE MOST RECENT
GEFS/ECMWF ENSEMBLE GUIDANCE SHOW GOOD CORRELATION TO NEXT THURSDAY.

HIGH PRESSURE AND UPPER LEVEL RIDGE OVER THE REGION WILL BEGIN TO
EXIT BY MONDAY. AT THE SURFACE APPEARS ANOTHER INVERTED
TROUGH/ONSHORE FLOW WILL YIELD TO PRECIP ALONG THE MASS COASTLINE ON
MONDAY. ASIDE FROM THIS QUICK MESOSCALE EVENT THE MAIN FOCUS IS ON
THE LONGWAVE DIGGING TROUGH OVER THE CENTRAL CONUS WHICH WILL PUSH A
FEW SHORTWAVES THROUGH THE FLOW. FIRST ONE DEVELOPS A WEAK WAVE
MOVING TOWARDS THE REGION LATE MONDAY INTO TUESDAY. THERE IS STILL
SOME UNCERTAINTY WITH THE LOCATION/STRENGTH OF THIS SYSTEM BUT
APPEARS THAT THERE IS THE POSSIBILITY OF A SNOW/WINTRY MIX IN THE
INTERIOR. AS THIS SYSTEM DEPARTS AN ANOMALOUS LOW OVER THE GREAT
LAKES WILL DEVELOP A SECONDARY LOW JUST WEST OF SOUTHERN NEW ENGLAND
     PER ENSEMBLE GUIDANCE. STILL A SOME SPREAD BUT IF THIS DOUBLE LOW
DOES DEVELOP THEN THE RAIN AND WIND ASPECT OF THE SYSTEM
INCREASES...DETAILS BELOW. STILL NEED TO WORK OUT MINOR DETAILS WITH
THIS PARTICULAR SYSTEM BUT WITH 3 TO 4 STANDARD DEVIATIONS AWAY AND
GENERAL MODEL AGREEMENT HAVE HIGH CONFIDENCE THIS SYSTEM WILL IMPACT
SOUTHERN NEW ENGLAND.

DETAILS...

SUNDAY NIGHT INTO TUESDAY...MODERATE CONFIDENCE.

HIGH PRESSURE AND UPPER LEVEL RIDGE WILL BEGIN TO MOVE OFFSHORE AS
DIGGING TROUGH BEGINS TO SET-UP OVER THE CENTRAL CONUS. APPEARS
ANOTHER MESO-SCALE INVERTED TROUGH WILL SET UP ON MONDAY AND LAST
INTO EARLY TUESDAY MORNING. GUIDANCE SHOWS THAT RAIN/SNOW SHOWERS
WILL DEVELOP ALONG THE MASS EAST COASTLINE THANKS TO ONSHORE
EASTERLY FLOW. APPEARS THE COLUMN WILL SATURATE PER BUFKIT SOUNDINGS
AND SOUTHERLY FLOW ALOFT. BOTH THE NAM AND GFS SHOW QPF MAKING IT
ONSHORE DURING THIS TIME FRAME. HOWEVER THE EC IS SLIGHTLY SLOWER
AND KEEP THE BULK OF THE PRECIP JUST OFFSHORE. ADD A CHANCE OF POPS
DUE TO THE NAM/GFS MODEL CONTINUITY.

BY LATE MONDAY NIGHT INTO TUESDAY A SOUTHERN BRANCH STORM SYSTEM
FORMS ALONG THE SE COAST AND TAKES A TRACK OFF THE MID ATLANTIC
COAST. THIS SYSTEM GETS CAUGHT UP WITH THE OVERALL LARGE SCALE
AMPLIFICATION OF THE UPPER AIR PATTERN. THERE IS DECENT WARM
ADVECTION WITH COLD AIR DAMMING ACROSS THE INTERIOR. BIGGEST
QUESTION WILL BE IS THERE ENOUGH MOISTURE FOR PRECIP DURING THIS
TIME FRAME. IF PRECIP OVERRUNS THEN COULD SEE FREEZING RAIN/DRIZZLE
ACROSS THE INTERIOR LATE MONDAY INTO TUESDAY MORNING. DURING THE DAY
ON TUESDAY...GOOD AMOUNT OF WARM AIR WILL PUSH SURFACE TEMPS ABOVE
FREEZING ALLOWING FOR ANY PRECIP TO BE MORE OF THE LIQUID VARIETY
AHEAD OF THE CHRISTMAS EVE STORM. HOWEVER GUIDANCE IS ALWAYS TOO
FAST IN SCOURING TEMPS OUT ESP ACROSS THE CT VALLEY SO WE WILL NEED
TO MONITOR THIS CLOSELY...ESP DUE TO LIGHT WINDS AND THE HIGH IN
EASTERN CANADA.

WE COULD ALSO SEE SOME MINOR COASTAL FLOODING CONCERNS ON TUESDAY. SEE
BELOW FOR MORE DETAILS.

WEDNESDAY INTO THURSDAY...HIGH CONFIDENCE IN SYSTEM LOW CONFIDENCE
ON DETAILS.

STRONG ANOMALOUS SYSTEM WILL STRENGTHEN OVER THE GREAT
LAKES...DEVELOPING A POTENTIAL SECONDARY SURFACE LOW JUST WEST OF
SOUTHERN NEW ENGLAND. STILL A LOT OF DETAILS TO WORK OUT AS THIS
SYSTEM IS STILL 5 DAYS AWAY...HOWEVER ENSEMBLES CONTINUE TO SHOW
STRONG AGREEMENT SO HAVE INCREASING CONFIDENCE THAT A POTENT STORM
WILL OCCUR. LATEST 00Z GUIDANCE SHOWS THAT MOST PRECIP WILL BE
LIQUID WITH A DEEP SUBTROPICAL CONNECTION BACK ACROSS THE GULF OF
MEXICO...PW ANOMALIES FORECAST TO RISE BETWEEN +3 TO +4. CURRENT
PWATS ARE PROGGED ABOVE 1.6 INCHES SO HAVE CONTINUED THE CATEGORICAL
POPS. TEMPERATURES WILL BE WELL ABOVE AVERAGE...IN FACT WE MAY BE
CLOSE AT BREAKING RECORD HIGH TEMPS IF TEMPS WARM TO 60F OR ABOVE ON
CHRISTMAS EVE.  AS THE SYSTEM WRAPS UP INTO CANADA...COLD AIR
ADVECTION SHOULD CIRCULATE AROUND AND BEGIN A TRANSITION FROM
SOUTHWEST TO NORTHEAST IN TURNING P-TYPE TO SNOW. HOWEVER LATEST
GUIDANCE DOES SHOW A QUICK MOVING DRY SLOT SO SNOWFALL WILL STRUGGLE
DUE TO LACK OF MOISTURE.

THIS SYSTEM IS QUITE POTENT SO WE WILL NEED TO WATCH FOR POTENTIAL
HAZARDS. CURRENTLY THINK THAT WE COULD POSSIBLE URBAN FLOODING
ISSUES AS MODELS PROGGED WELL OVER 1.5 INCHES OF QPF. LATEST EC EVEN
SHOWS 2.5 INCHES OF QPF IS POSSIBLE. THE GEFS SHOW A MOISTURE FLUX
AT 850 MB BEING 4 TO 5 STANDARD DEVIATIONS AWAY...AND WITH THE
TROPICAL CONNECTION AND STRONG SOUTHERLY FLOW COULD SEE HIGHER
AMOUNTS DUE TO TOPOGRAPHY ENHANCEMENTS. RAIN FALL RECORDS MAY FALL
IF EVERYTHING FALLS INTO PLACE.

ALSO BELIEVE THAT WE MAY SEE SOME WIND ISSUES WITH THIS SYSTEM.
GUIDANCE RIGHT NOW IS SHOWING A 45 TO 55 KT JET AT 925 MB...HOWEVER
IT WILL BE HARD TO BREAK THE INVERSION WITH THE SOUTHERLY FLOW.
RIGHT NOW BELIEVE THAT WIND ADVISORIES MAY BE NEEDED BUT IF THIS
SYSTEM STRENGTHEN EVEN MORE SO A STRONGER JET IS POSSIBLE.

CONTINUED THE MENTIONED OF ISOLATED THUNDER IN THE FORECAST PER PREV
FORECASTER SUGGESTION. BELIEVE IT COULD BE POSSIBLE AS SOUTHERN NEW
ENGLAND WILL BE IN THE WARM SECTOR...WITH THE ANOMALOUS JET AND
SHOWALTERS CLOSE TO ZERO.

FRIDAY...LOW CONFIDENCE.

ONCE UPPER LEVEL LOW MOVES INTO SOUTHERN CANADA...EXPECT A RATHER
FAST UPPER W FLOW IN PLACE. MAY SEE LEFTOVER SNOW SHOWERS BUT TEMPS
WILL FALL BACK CLOSE TO SEASONAL NORMS.

&&

.AVIATION /15Z SATURDAY THROUGH WEDNESDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH SUNDAY/...

700 AM UPDATE...

TODAY...MODERATE CONFIDENCE.  MVFR CIGS WILL CONTINUE TO OVERSPREAD
EASTERN NEW ENGLAND THIS MORNING AND EVENTUALLY INTO THE INTERIOR
THIS AFTERNOON.  SCATTERED PRECIPITATION WILL OVERSPREAD
SOUTHEAST MA/CAPE/ISLANDS THIS AFTERNOON.  PTYPE MAINLY SNOW SHOWERS
NORTHWEST OF THE SOUTHEAST PLYMOUTH COUNTY COAST AND RAIN SHOWERS
SOUTHEAST OF THAT REGION. LOCALIZED IFR CONDITIONS POSSIBLE JUST
INLAND FROM THE SOUTHEAST NEW ENGLAND COAST...WHERE PTYPE IS SNOW.

TONIGHT AND SUNDAY...MODERATE CONFIDENCE.  MVFR CONDITIONS DOMINATE
IN LOWER CLOUDS AND SCATTERED PRECIPITATION.  LOCALIZED IFR
CONDITIONS POSSIBLE WITH THE BEST CHANCE IN SNOW SHOWERS.
PRECIPITATION AFFECTS MAINLY EASTERN NEW ENGLAND BUT STILL SOME
SCATTERED ACTIVITY ACROSS WESTERN NEW ENGLAND. PTYPE MAINLY SNOW
SHOWERS NORTHWEST OF THE SOUTHEAST PLYMOUTH COUNTY COAST...WITH RAIN
SHOWERS SOUTHEAST OF THAT REGION.

KBOS TERMINAL...MODERATE CONFIDENCE IN TAF.  SNOW SHOWERS MAY ARRIVE
TOWARDS 00Z THIS EVENING.

KBDL TERMINAL...MODERATE CONFIDENCE IN TAF.

OUTLOOK...SUNDAY NIGHT THROUGH WEDNESDAY...

MONDAY INTO TUESDAY...MODERATE CONFIDENCE. EXPECT MOSTLY
VFR...ISOLATED MVFR ALONG THE MASS EAST COASTLINE IN RAIN/SNOW
SHOWERS.

TUESDAY NIGHT INTO WEDNESDAY...MODERATE CONFIDENCE. CONDITIONS WILL
BE DETERIORATING AS HEAVY DOWNPOURS...ISO THUNDER AND GUSTY SOUTHERLY
WINDS MOVE INTO THE REGION BY WEDNESDAY. COULD SEE MVFR TO IFR
CONDITIONS IN CIGS AND VSBYS.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /TODAY THROUGH SUNDAY/...HIGH CONFIDENCE.

HIGH PRESSURE ACROSS QUEBEC WILL RESULT IN PERSISTENT NORTHEAST
WINDS ACROSS THE WATERS THROUGH THE WEEKEND.  WIND GUSTS UP TO 20
KNOTS WITH SEAS BETWEEN 2 AND 4 FEET ARE EXPECTED FOR MOST
WATERS...SO NO HEADLINES PLANNED. THERE IS A LOW PROBABILITY THAT A
BRIEF SURGE OF NORTHEAST WIND GUSTS NEAR 25 KNOTS WITH MARGINAL 5
FOOT SEAS COULD AFFECT OUR NORTHERN WATERS LATE TONIGHT INTO SUN
MORNING...BUT NOT CONFIDENT ENOUGH TO ISSUE ANY HEADLINES AT THIS
POINT.

OUTLOOK...SUNDAY NIGHT INTO WEDNESDAY...MODERATE TO HIGH
CONFIDENCE.

SUNDAY INTO MONDAY. CONTINUOUS NORTHEAST FLOW WILL KEEP SEAS CHOPPY.
LINGERING NORTHEAST SWELL MAY BUMP SEAS ABOVE 5FT ESP ACROSS THE
NORTHEASTERN WATERS. SCA MAY BE NEEDED...BUT LOWER CONFIDENCE.

TUESDAY INTO WEDNESDAY...NE WINDS WILL INCREASE...GUSTING TO 30 KT
TUE THEN SHIFT TO SE GUSTING TO 30-35 KT WED...HIGHEST ON THE OUTER
WATERS. SEAS BUILD UP TO 7-11 FT BY WED. GALES WILL BE NEEDED.

&&

.TIDES/COASTAL FLOODING...
HIGH ASTRONOMICAL TIDES WILL OCCUR TUESDAY THROUGH THURSDAY. BREAKING
IT DOWN...ON TUESDAY HIGH TIDE AT BOSTON WILL BE 11.6 FT. THERE WILL
BE ONSHORE FLOW DURING THIS HIGH TIDE ALLOWING FOR MINOR SPLASHOVER.
IF WIND GUSTS INCREASE THEN COULD POSSIBLE SEE MINOR COASTAL
FLOODING.

ON WEDNESDAY...WINDS WILL SWITCH TO A MORE SOUTHEASTERLY FLOW DURING
THE DAY AND INCREASE QUICKLY FROM APPROACHING SYSTEM AND DESCENT
PRESSURE FALLS. WEDNESDAY AFTERNOON HIGH TIDE IN BOSTON IS 11.7 FT
AND WITH ANY STRENGTH ON THE EASTERLY WIND FLOW WILL PUSH THE TIDE
OVER. RIGHT NOW BELIEVE MINOR COASTAL FLOODING IS POSSIBLE ALONG THE
EAST COASTLINE. HOWEVER WEDNESDAY EVENING...THE WIND GOES IN A MORE
SOUTHERLY DIRECTION AND HIGH TIDE IN PROVIDENCE WILL BE 5.2 FT. 925
MB LLJ STRENGTHENS TO 50-60 KTS WHICH COULD PUSH A DESCENT SURGE UP
ALONG THE SOUTH COAST DURING THE TIME OF HIGH TIDE. THINKING THAT
MINOR COASTAL FLOODING COULD OCCUR BUT CANNOT RULE OUT MODERATE
ALONG THE SOUTH COAST...ESP IF LLJ STRENGTHENS EVEN MORE.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...FRANK/DUNTEN
NEAR TERM...FRANK/DUNTEN/RLG
SHORT TERM...FRANK
LONG TERM...DUNTEN
AVIATION...FRANK/DUNTEN
MARINE...FRANK/DUNTEN
TIDES/COASTAL FLOODING...




000
FXUS61 KGYX 201447
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
947 AM EST SAT DEC 20 2014

.SYNOPSIS...
WEAK HIGH PRESSURE MOVES ACROSS THE REGION THROUGH SATURDAY. THE
HIGH BUILDS OVER NORTHERN MAINE SUNDAY...ALLOWING THE FLOW TO TURN
ONSHORE. A WEAK WEATHER DISTURBANCE MAY TRIGGER SOME FLURRIES OR
LIGHT SNOW OVER SOUTHERN REGIONS LATER SUNDAY INTO MONDAY. A WEAK
AREA OF LOW PRESSURE WILL MOVE UP THE COAST TUESDAY...WITH A MORE
SIGNIFICANT SYSTEM GRADUALLY ORGANIZING WEDNESDAY...BEFORE MOVING
OVER THE GREAT LAKES. THIS COULD BRING WINDY CONDITIONS AND THE
POTENTIAL FOR HEAVY RAIN AROUND CHRISTMAS EVE INTO EARLY CHRISTMAS
MORNING.

&&

.NEAR TERM /THROUGH TONIGHT/...
UPDATE...
HAVE UPDATED THE GRIDS BASED ON CURRENT CONDITIONS AND LATEST
SUITE OF MESOSCALE MODELS. HAVE INCREASED CLOUD GRIDS FOR THE
IMMEDIATE COASTLINE AND THE COASTAL WATERS FOR TODAY AND TONIGHT.
STRONGEST WESTWARD PUSH OF THE LOW SC OVER THE GULF OF MAINE
CONTUINUES TO BE OVER THE NH SEACOAST. HAVE INCREASED POPS FOR
THIS REGION FOR LATER TODAY AND TONIGHT...BRINGING A LIGHT COATING
OF SNOWFALL TO THAT REGION.

MAD MINOR ADJUSTMENTS TO TODAYS WIND FORECAST...OTHERWISE
FORECAST ON TRACK.

PREV DISC...
7 AM UPDATE...SOME IMPRESSIVE RADIATIONAL COOLING
ACROSS THE NORTH THIS MORNING...WITH LOWS NOW DROPPING BELOW ZERO.
UPDATED THE LOW TEMPERATURE FORECAST BASED ON THE CURRENT OBS AND
TRENDS...AS GUIDANCE WAS OVER 10 DEGREES OFF IN MANY AREAS ACROSS
THE NORTH. STILL JUST A FEW CLOUDS HOLDING ON IN THE CT RIVER
VALLEY...OTHERWISE MOSTLY CLEAR SKIES ELSEWHERE. FORECAST IS STILL
ON TRACK FOR CLOUDS TO INCREASE THROUGH OUT THE DAY WITH LOW
STRATUS PUSHING IN FROM THE OCEAN AND FROM THE NORTH.

PREVIOUS DISCUSSION...
A WEAK SHORT WAVE IS CLEARLY VISIBLE ON
WATER VAPOR IMAGERY MOVING EAST ACROSS NY AS OF 3AM. OTHER THAN
THE CT RIVER VALLEY THE BULK OF THE CWA IS MOSTLY CLEAR. AS THE
SHORT WAVE APPROACHES WE SHOULD SEE NORTHEAST FLOW SWITCH AT 925MB
TO MORE ON SHORE EAST TO SOUTHEASTERLY FLOW. THIS WILL START TO
ADVECT LOW CLOUDS IN OFF THE OCEAN. LOW CLOUDS MOVING AROUND THE
SURFACE HIGH TO THE NORTH WILL ALSO START TO PUSH IN FROM THE
NORTHEAST. SO MOST OF THE AREA WILL GO FROM CLEAR TO MOSTLY
CLOUDY/OVERCAST SKIES BY THIS EVENING.

&&

.SHORT TERM /SUNDAY/...
LOW LEVEL ONSHORE FLOW BELOW THE RIDGE ALOFT WILL PUSH MOISTURE
INLAND. THE WEAK SHORT WAVE TROF WILL BE THE FOCUS AS IT CONTINUES
TO DRIFT EASTWARD ACROSS THE REGION LATE TONIGHT AND EARLY SUNDAY.
AN INVERTED TROUGH SETS UP AT THE SURFACE ACROSS THE FAR SOUTHERN
CWA. THIS COMBINED WITH THE SHORT WAVE SHOULD ALLOW ENOUGH
FORCING FOR ASCENT TO SATURATE UP TO 700MB. AS MENTIONED IN
YESTERDAY`S AFTERNOON FORECAST PACKAGE...THIS SETS UP A NICE
SEEDER-FEEDER PROCESS TO INCREASE THE SNOW SHOWER ACTIVITY ACROSS
SOUTHERN ZONES IN SOUTHEASTERN NEW HAMPSHIRE AND POSSIBLY COASTAL
YORK COUNTY. THERE IS GOOD MODEL AGREEMENT BETWEEN MESOSCALE AND
SYNOPTIC MODELS HINTING AT LIGHT QPF IN THESE AREAS...AND
ACCUMULATING SNOWFALL MAY BE POSSIBLE. USED A BLEND OF
NAM/GFS/ARW/NMM FOR POP AND QPF FORECAST.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
MEDIUM RANGE MODELS CONTINUE TO TRANSITION FROM A HIGHER WAVE
NUMBER TO A LOWER ONE NEXT WEEK WITH STRONG BLOCKING UPSTREAM AND
DOWNSTREAM AND MEAN TROUGH DEVELOPING ACROSS NRN TWO THIRDS OF
NOAM. THE TRANSITION PERIOD WILL MAKE FOR AN ACTIVE WX WEEK.
HOWEVER...WE LOOK TO STAY ON THE WARM SIDE OF THE TROUGH THROUGH
FRIDAY...WITH HIGHS RUNNING ABV NORMAL AND MAINLY RAIN.

BEST CHC FOR ANY ACCUMULATING SNOW IN THE EXTENDED WILL BE ALONG
THE COAST SUNDAY NIGHT INTO EARLY MONDAY AS MODELS INDICATING
DEVELOPMENT OF INVERTED TROUGH. NAM12/GFS IN FAIR AGREEMENT AS TO
TIMING AND LOCATION...DEVELOPING ALONG THE MID-COAST SUN
NIGHT...AND SHIFT WEST TOWARD THE NH AND SW ME COASTS DURING THE
DAY ON MONDAY. EURO TENDS TO HOLD THE QPF AROUND AND E OF
PENOBSCOT BAY UNTIL LATE MONDAY AND THEN SHIFTS IT EAST MONDAY
NIGHT. THE AGREEMENT BETWEEN THE NAM AND GFS THIS FAR OUT IS
INTERESTING...SINCE MODELS TEND TO NOT HANDLE THESE INVERTED
TROUGHS WELL UNTIL THEY IN THE 12-24 HOUR RANGE....BUT HAVE
GENERALLY FOLLOWED A NAM/GFS BLEND SUN NIGHT THRU MON NIGHT. QPF
WILL BE LIGHT AND SUN NIGHT IS THE BEST CHC FOR ANY ACCUMS AS
PRECIP WILL LKLY MIX WITH OR CHANGE TO RAIN DURING THE DAY
MONDAY...AND EVEN IF IT DOES STAY AS SNOW...WILL HAVE TOUGH TIME
ACCUMULATING. THE ONE THING TO WATCH FRO WITH INVERTED TROUGHS IS
IF IT LOCKS INTO ONE AREA...AND SETS UP CONVERGENT ONSHORE FLOW
SIMILAR TO COASTAL FRONT...WHICH WOULD GIVE A SPECIFIC AREA
SEVERAL INCHES WITH VERY LITTLE ELSEWHERE. FOR NOW...HOLDING ONTO
THE IDEA OF A MOVING TROUGH WITH ACCUMS OF A COATING IN MOST
SPOTS. INLAND JUST LOOKS FOR MAINLY CLOUDY SKIES IN THIS TIME
FRAMEWITH A FEW FLURRIES.

MAY SEE A LITTLE BIT OF A BREAK ON TUE AS WEAK OFFSHORE SFC LOW
EXITS AND ALLOWS SOME RIDGING TO BUILD BACK IN FROM THE NE...THEN
WE START GETTING INTO THE EFFECTS OF THE IMPRESSIVE STORM SYSTEM
THAT RAPIDLY INTENSIFIES TO OUR WEST. PRECIP MOVES IN TUE
NIGHT...WHICH WILL BEGIN AS RAIN ALONG THE COAST...WITH EARLY LOWS
IN THE MID TO UPPER 30S. INLAND...PRECIP WILL START AS SNOW...AND
TRANSITIONS TO FREEZING RAIN OR RAIN LATE TUE NIGHT...AND
EVENTUALLY TRANSITION TO RAIN WED MORNING. THE HEAVY PRECIP WILL
MAINLY FALL AS RAIN WED AFTERNOON AND WED NIGHT. GFS QPF SEEMS
HIGH...AS IT MAY BE DEALING WITH CONVECTIVE SCALING ISSUES...AND
THE 1.5-2.5" OF THE EURO SEEMS MORE REASONABLE ATTM...STRONG SE
FLOW DEVELOPS EAST OF THE OCCLUSION POINT WHICH CROSSES WRN NEW
ENGLAND WED NIGHT. WILL SEE STRONG LOW LEVEL SE JET DEVELOP ABOVE
THE INVERSION AROUND THIS TIME AS WELL...AND ALTHOUGH THE
INVERSION SHOULD PREVENT FULL MIXING...ESPECIALLY OVER
LAND...COULD SEE WIND GUSTS APPROACHING ADV LEVELS. HIGHS WED WILL
LKLY OCCUR LATE IN THE DAY WED OR WED EVE...AND WILL MAKE A RUN AT
50 IN SRN NH AND ALONG THE COAST.

SHARP BACK EDGE TO THE RAIN WILL CROSS THE REGION EARLY WED AND
RAIN SHOULD END FROM SW TO NE DURING THE MORNING AND EARLY
AFTERNOON...WITH SOME PARTIAL CLEARING POSSIBLE IN THE AFTERNOON.
GUSTY W-SW WINDS WILL DEVELOP BEHIND THE SYSTEM....BUT HIGHS WILL
STILL BE ABV NORMAL...IN THE 40S.

&&

.AVIATION /15Z SATURDAY THROUGH WEDNESDAY/...
SHORT TERM...MVFR CONDITIONS WILL CONTINUE UNTIL ABOUT DAYBREAK
IN THE CT RIVER VALLEY AS LOW LEVEL MOISTURE HAS BECOME TRAPPED.
SHOULD SEE ALL AREAS RETURN TO VFR DURING THE DAY AND THEN MORE
MOISTURE WILL WORK ITS WAY INTO THE REGION AS LOW LEVEL WIND FLOW
TURNS ON SHORE. THIS WILL BRING SOME MVFR CEILING AND POSSIBLE
SOME LIGHT SNOW SHOWERS FROM SATURDAY EVENING THROUGH MONDAY.


LONG TERM...POSSIBLE PERIODS OF MVFR TO IFR AT COASTAL TERMINALS
SUN NIGHT INTO MONDAY AS INVERTED TROUGH DEVELOPS ACROSS THE GULF
OF ME. MVFR LIKELY TO HOLD TUE INTO TUE NIGHT...WITH LOWERING TO
IFR LATE TUE NIGHT AND WED IN RAIN...WITH INCREASING E-SE WINDS
LATE IN THE DAY WED.

&&

.MARINE...
SHORT TERM...WINDS AND SEAS WILL REMAIN BELOW SCA CONDITIONS THRU
SUNDAY.

LONG TERM...WATER REMAIN BLO SCA LVLS SUN NIGHT THROUGH TUE
NIGHT. STRONG LOW PRES TO THE WEST WILL SEE WINDS INCREASE TO
GALES WED AFTERNOON WITH BORDERLINE STORM FORCE WINDS POSSIBLE WED
NIGHT.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.

&&

$$




000
FXUS61 KGYX 201447
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
947 AM EST SAT DEC 20 2014

.SYNOPSIS...
WEAK HIGH PRESSURE MOVES ACROSS THE REGION THROUGH SATURDAY. THE
HIGH BUILDS OVER NORTHERN MAINE SUNDAY...ALLOWING THE FLOW TO TURN
ONSHORE. A WEAK WEATHER DISTURBANCE MAY TRIGGER SOME FLURRIES OR
LIGHT SNOW OVER SOUTHERN REGIONS LATER SUNDAY INTO MONDAY. A WEAK
AREA OF LOW PRESSURE WILL MOVE UP THE COAST TUESDAY...WITH A MORE
SIGNIFICANT SYSTEM GRADUALLY ORGANIZING WEDNESDAY...BEFORE MOVING
OVER THE GREAT LAKES. THIS COULD BRING WINDY CONDITIONS AND THE
POTENTIAL FOR HEAVY RAIN AROUND CHRISTMAS EVE INTO EARLY CHRISTMAS
MORNING.

&&

.NEAR TERM /THROUGH TONIGHT/...
UPDATE...
HAVE UPDATED THE GRIDS BASED ON CURRENT CONDITIONS AND LATEST
SUITE OF MESOSCALE MODELS. HAVE INCREASED CLOUD GRIDS FOR THE
IMMEDIATE COASTLINE AND THE COASTAL WATERS FOR TODAY AND TONIGHT.
STRONGEST WESTWARD PUSH OF THE LOW SC OVER THE GULF OF MAINE
CONTUINUES TO BE OVER THE NH SEACOAST. HAVE INCREASED POPS FOR
THIS REGION FOR LATER TODAY AND TONIGHT...BRINGING A LIGHT COATING
OF SNOWFALL TO THAT REGION.

MAD MINOR ADJUSTMENTS TO TODAYS WIND FORECAST...OTHERWISE
FORECAST ON TRACK.

PREV DISC...
7 AM UPDATE...SOME IMPRESSIVE RADIATIONAL COOLING
ACROSS THE NORTH THIS MORNING...WITH LOWS NOW DROPPING BELOW ZERO.
UPDATED THE LOW TEMPERATURE FORECAST BASED ON THE CURRENT OBS AND
TRENDS...AS GUIDANCE WAS OVER 10 DEGREES OFF IN MANY AREAS ACROSS
THE NORTH. STILL JUST A FEW CLOUDS HOLDING ON IN THE CT RIVER
VALLEY...OTHERWISE MOSTLY CLEAR SKIES ELSEWHERE. FORECAST IS STILL
ON TRACK FOR CLOUDS TO INCREASE THROUGH OUT THE DAY WITH LOW
STRATUS PUSHING IN FROM THE OCEAN AND FROM THE NORTH.

PREVIOUS DISCUSSION...
A WEAK SHORT WAVE IS CLEARLY VISIBLE ON
WATER VAPOR IMAGERY MOVING EAST ACROSS NY AS OF 3AM. OTHER THAN
THE CT RIVER VALLEY THE BULK OF THE CWA IS MOSTLY CLEAR. AS THE
SHORT WAVE APPROACHES WE SHOULD SEE NORTHEAST FLOW SWITCH AT 925MB
TO MORE ON SHORE EAST TO SOUTHEASTERLY FLOW. THIS WILL START TO
ADVECT LOW CLOUDS IN OFF THE OCEAN. LOW CLOUDS MOVING AROUND THE
SURFACE HIGH TO THE NORTH WILL ALSO START TO PUSH IN FROM THE
NORTHEAST. SO MOST OF THE AREA WILL GO FROM CLEAR TO MOSTLY
CLOUDY/OVERCAST SKIES BY THIS EVENING.

&&

.SHORT TERM /SUNDAY/...
LOW LEVEL ONSHORE FLOW BELOW THE RIDGE ALOFT WILL PUSH MOISTURE
INLAND. THE WEAK SHORT WAVE TROF WILL BE THE FOCUS AS IT CONTINUES
TO DRIFT EASTWARD ACROSS THE REGION LATE TONIGHT AND EARLY SUNDAY.
AN INVERTED TROUGH SETS UP AT THE SURFACE ACROSS THE FAR SOUTHERN
CWA. THIS COMBINED WITH THE SHORT WAVE SHOULD ALLOW ENOUGH
FORCING FOR ASCENT TO SATURATE UP TO 700MB. AS MENTIONED IN
YESTERDAY`S AFTERNOON FORECAST PACKAGE...THIS SETS UP A NICE
SEEDER-FEEDER PROCESS TO INCREASE THE SNOW SHOWER ACTIVITY ACROSS
SOUTHERN ZONES IN SOUTHEASTERN NEW HAMPSHIRE AND POSSIBLY COASTAL
YORK COUNTY. THERE IS GOOD MODEL AGREEMENT BETWEEN MESOSCALE AND
SYNOPTIC MODELS HINTING AT LIGHT QPF IN THESE AREAS...AND
ACCUMULATING SNOWFALL MAY BE POSSIBLE. USED A BLEND OF
NAM/GFS/ARW/NMM FOR POP AND QPF FORECAST.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
MEDIUM RANGE MODELS CONTINUE TO TRANSITION FROM A HIGHER WAVE
NUMBER TO A LOWER ONE NEXT WEEK WITH STRONG BLOCKING UPSTREAM AND
DOWNSTREAM AND MEAN TROUGH DEVELOPING ACROSS NRN TWO THIRDS OF
NOAM. THE TRANSITION PERIOD WILL MAKE FOR AN ACTIVE WX WEEK.
HOWEVER...WE LOOK TO STAY ON THE WARM SIDE OF THE TROUGH THROUGH
FRIDAY...WITH HIGHS RUNNING ABV NORMAL AND MAINLY RAIN.

BEST CHC FOR ANY ACCUMULATING SNOW IN THE EXTENDED WILL BE ALONG
THE COAST SUNDAY NIGHT INTO EARLY MONDAY AS MODELS INDICATING
DEVELOPMENT OF INVERTED TROUGH. NAM12/GFS IN FAIR AGREEMENT AS TO
TIMING AND LOCATION...DEVELOPING ALONG THE MID-COAST SUN
NIGHT...AND SHIFT WEST TOWARD THE NH AND SW ME COASTS DURING THE
DAY ON MONDAY. EURO TENDS TO HOLD THE QPF AROUND AND E OF
PENOBSCOT BAY UNTIL LATE MONDAY AND THEN SHIFTS IT EAST MONDAY
NIGHT. THE AGREEMENT BETWEEN THE NAM AND GFS THIS FAR OUT IS
INTERESTING...SINCE MODELS TEND TO NOT HANDLE THESE INVERTED
TROUGHS WELL UNTIL THEY IN THE 12-24 HOUR RANGE....BUT HAVE
GENERALLY FOLLOWED A NAM/GFS BLEND SUN NIGHT THRU MON NIGHT. QPF
WILL BE LIGHT AND SUN NIGHT IS THE BEST CHC FOR ANY ACCUMS AS
PRECIP WILL LKLY MIX WITH OR CHANGE TO RAIN DURING THE DAY
MONDAY...AND EVEN IF IT DOES STAY AS SNOW...WILL HAVE TOUGH TIME
ACCUMULATING. THE ONE THING TO WATCH FRO WITH INVERTED TROUGHS IS
IF IT LOCKS INTO ONE AREA...AND SETS UP CONVERGENT ONSHORE FLOW
SIMILAR TO COASTAL FRONT...WHICH WOULD GIVE A SPECIFIC AREA
SEVERAL INCHES WITH VERY LITTLE ELSEWHERE. FOR NOW...HOLDING ONTO
THE IDEA OF A MOVING TROUGH WITH ACCUMS OF A COATING IN MOST
SPOTS. INLAND JUST LOOKS FOR MAINLY CLOUDY SKIES IN THIS TIME
FRAMEWITH A FEW FLURRIES.

MAY SEE A LITTLE BIT OF A BREAK ON TUE AS WEAK OFFSHORE SFC LOW
EXITS AND ALLOWS SOME RIDGING TO BUILD BACK IN FROM THE NE...THEN
WE START GETTING INTO THE EFFECTS OF THE IMPRESSIVE STORM SYSTEM
THAT RAPIDLY INTENSIFIES TO OUR WEST. PRECIP MOVES IN TUE
NIGHT...WHICH WILL BEGIN AS RAIN ALONG THE COAST...WITH EARLY LOWS
IN THE MID TO UPPER 30S. INLAND...PRECIP WILL START AS SNOW...AND
TRANSITIONS TO FREEZING RAIN OR RAIN LATE TUE NIGHT...AND
EVENTUALLY TRANSITION TO RAIN WED MORNING. THE HEAVY PRECIP WILL
MAINLY FALL AS RAIN WED AFTERNOON AND WED NIGHT. GFS QPF SEEMS
HIGH...AS IT MAY BE DEALING WITH CONVECTIVE SCALING ISSUES...AND
THE 1.5-2.5" OF THE EURO SEEMS MORE REASONABLE ATTM...STRONG SE
FLOW DEVELOPS EAST OF THE OCCLUSION POINT WHICH CROSSES WRN NEW
ENGLAND WED NIGHT. WILL SEE STRONG LOW LEVEL SE JET DEVELOP ABOVE
THE INVERSION AROUND THIS TIME AS WELL...AND ALTHOUGH THE
INVERSION SHOULD PREVENT FULL MIXING...ESPECIALLY OVER
LAND...COULD SEE WIND GUSTS APPROACHING ADV LEVELS. HIGHS WED WILL
LKLY OCCUR LATE IN THE DAY WED OR WED EVE...AND WILL MAKE A RUN AT
50 IN SRN NH AND ALONG THE COAST.

SHARP BACK EDGE TO THE RAIN WILL CROSS THE REGION EARLY WED AND
RAIN SHOULD END FROM SW TO NE DURING THE MORNING AND EARLY
AFTERNOON...WITH SOME PARTIAL CLEARING POSSIBLE IN THE AFTERNOON.
GUSTY W-SW WINDS WILL DEVELOP BEHIND THE SYSTEM....BUT HIGHS WILL
STILL BE ABV NORMAL...IN THE 40S.

&&

.AVIATION /15Z SATURDAY THROUGH WEDNESDAY/...
SHORT TERM...MVFR CONDITIONS WILL CONTINUE UNTIL ABOUT DAYBREAK
IN THE CT RIVER VALLEY AS LOW LEVEL MOISTURE HAS BECOME TRAPPED.
SHOULD SEE ALL AREAS RETURN TO VFR DURING THE DAY AND THEN MORE
MOISTURE WILL WORK ITS WAY INTO THE REGION AS LOW LEVEL WIND FLOW
TURNS ON SHORE. THIS WILL BRING SOME MVFR CEILING AND POSSIBLE
SOME LIGHT SNOW SHOWERS FROM SATURDAY EVENING THROUGH MONDAY.


LONG TERM...POSSIBLE PERIODS OF MVFR TO IFR AT COASTAL TERMINALS
SUN NIGHT INTO MONDAY AS INVERTED TROUGH DEVELOPS ACROSS THE GULF
OF ME. MVFR LIKELY TO HOLD TUE INTO TUE NIGHT...WITH LOWERING TO
IFR LATE TUE NIGHT AND WED IN RAIN...WITH INCREASING E-SE WINDS
LATE IN THE DAY WED.

&&

.MARINE...
SHORT TERM...WINDS AND SEAS WILL REMAIN BELOW SCA CONDITIONS THRU
SUNDAY.

LONG TERM...WATER REMAIN BLO SCA LVLS SUN NIGHT THROUGH TUE
NIGHT. STRONG LOW PRES TO THE WEST WILL SEE WINDS INCREASE TO
GALES WED AFTERNOON WITH BORDERLINE STORM FORCE WINDS POSSIBLE WED
NIGHT.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.

&&

$$



000
FXUS61 KGYX 201204
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
704 AM EST SAT DEC 20 2014

.SYNOPSIS...
WEAK HIGH PRESSURE MOVES ACROSS THE REGION THROUGH SATURDAY. THE
HIGH BUILDS OVER NORTHERN MAINE SUNDAY...ALLOWING THE FLOW TO TURN
ONSHORE. A WEAK WEATHER DISTURBANCE MAY TRIGGER SOME FLURRIES OR
LIGHT SNOW OVER SOUTHERN REGIONS LATER SUNDAY INTO MONDAY. A WEAK
AREA OF LOW PRESSURE WILL MOVE UP THE COAST TUESDAY...WITH A MORE
SIGNIFICANT SYSTEM GRADUALLY ORGANIZING WEDNESDAY...BEFORE MOVING
OVER THE GREAT LAKES. THIS COULD BRING WINDY CONDITIONS AND THE
POTENTIAL FOR HEAVY RAIN AROUND CHRISTMAS EVE INTO EARLY CHRISTMAS
MORNING.

&&

.NEAR TERM /THROUGH TONIGHT/...
7 AM UPDATE...SOME IMPRESSIVE RADIATIONAL COOLING ACROSS THE NORTH
THIS MORNING...WITH LOWS NOW DROPPING BELOW ZERO. UPDATED THE LOW
TEMPERATURE FORECAST BASED ON THE CURRENT OBS AND TRENDS...AS
GUIDANCE WAS OVER 10 DEGREES OFF IN MANY AREAS ACROSS THE NORTH.
STILL JUST A FEW CLOUDS HOLDING ON IN THE CT RIVER
VALLEY...OTHERWISE MOSTLY CLEAR SKIES ELSEWHERE. FORECAST IS STILL
ON TRACK FOR CLOUDS TO INCREASE THROUGH OUT THE DAY WITH LOW
STRATUS PUSHING IN FROM THE OCEAN AND FROM THE NORTH.

PREVIOUS DISCUSSION...
A WEAK SHORT WAVE IS CLEARLY VISIBLE ON
WATER VAPOR IMAGERY MOVING EAST ACROSS NY AS OF 3AM. OTHER THAN
THE CT RIVER VALLEY THE BULK OF THE CWA IS MOSTLY CLEAR. AS THE
SHORT WAVE APPROACHES WE SHOULD SEE NORTHEAST FLOW SWITCH AT 925MB
TO MORE ON SHORE EAST TO SOUTHEASTERLY FLOW. THIS WILL START TO
ADVECT LOW CLOUDS IN OFF THE OCEAN. LOW CLOUDS MOVING AROUND THE
SURFACE HIGH TO THE NORTH WILL ALSO START TO PUSH IN FROM THE
NORTHEAST. SO MOST OF THE AREA WILL GO FROM CLEAR TO MOSTLY
CLOUDY/OVERCAST SKIES BY THIS EVENING.

&&

.SHORT TERM /SUNDAY/...
LOW LEVEL ONSHORE FLOW BELOW THE RIDGE ALOFT WILL PUSH MOISTURE
INLAND. THE WEAK SHORT WAVE TROF WILL BE THE FOCUS AS IT CONTINUES
TO DRIFT EASTWARD ACROSS THE REGION LATE TONIGHT AND EARLY SUNDAY.
AN INVERTED TROUGH SETS UP AT THE SURFACE ACROSS THE FAR SOUTHERN
CWA. THIS COMBINED WITH THE SHORT WAVE SHOULD ALLOW ENOUGH
FORCING FOR ASCENT TO SATURATE UP TO 700MB. AS MENTIONED IN
YESTERDAY`S AFTERNOON FORECAST PACKAGE...THIS SETS UP A NICE
SEEDER-FEEDER PROCESS TO INCREASE THE SNOW SHOWER ACTIVITY ACROSS
SOUTHERN ZONES IN SOUTHEASTERN NEW HAMPSHIRE AND POSSIBLY COASTAL
YORK COUNTY. THERE IS GOOD MODEL AGREEMENT BETWEEN MESOSCALE AND
SYNOPTIC MODELS HINTING AT LIGHT QPF IN THESE AREAS...AND
ACCUMULATING SNOWFALL MAY BE POSSIBLE. USED A BLEND OF
NAM/GFS/ARW/NMM FOR POP AND QPF FORECAST.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
MEDIUM RANGE MODELS CONTINUE TO TRANSITION FROM A HIGHER WAVE
NUMBER TO A LOWER ONE NEXT WEEK WITH STRONG BLOCKING UPSTREAM AND
DOWNSTREAM AND MEAN TROUGH DEVELOPING ACROSS NRN TWO THIRDS OF
NOAM. THE TRANSITION PERIOD WILL MAKE FOR AN ACTIVE WX WEEK.
HOWEVER...WE LOOK TO STAY ON THE WARM SIDE OF THE TROUGH THROUGH
FRIDAY...WITH HIGHS RUNNING ABV NORMAL AND MAINLY RAIN.

BEST CHC FOR ANY ACCUMULATING SNOW IN THE EXTENDED WILL BE ALONG
THE COAST SUNDAY NIGHT INTO EARLY MONDAY AS MODELS INDICATING
DEVELOPMENT OF INVERTED TROUGH. NAM12/GFS IN FAIR AGREEMENT AS TO
TIMING AND LOCATION...DEVELOPING ALONG THE MID-COAST SUN
NIGHT...AND SHIFT WEST TOWARD THE NH AND SW ME COASTS DURING THE
DAY ON MONDAY. EURO TENDS TO HOLD THE QPF AROUND AND E OF
PENOBSCOT BAY UNTIL LATE MONDAY AND THEN SHIFTS IT EAST MONDAY
NIGHT. THE AGREEMENT BETWEEN THE NAM AND GFS THIS FAR OUT IS
INTERESTING...SINCE MODELS TEND TO NOT HANDLE THESE INVERTED
TROUGHS WELL UNTIL THEY IN THE 12-24 HOUR RANGE....BUT HAVE
GENERALLY FOLLOWED A NAM/GFS BLEND SUN NIGHT THRU MON NIGHT. QPF
WILL BE LIGHT AND SUN NIGHT IS THE BEST CHC FOR ANY ACCUMS AS
PRECIP WILL LKLY MIX WITH OR CHANGE TO RAIN DURING THE DAY
MONDAY...AND EVEN IF IT DOES STAY AS SNOW...WILL HAVE TOUGH TIME
ACCUMULATING. THE ONE THING TO WATCH FRO WITH INVERTED TROUGHS IS
IF IT LOCKS INTO ONE AREA...AND SETS UP CONVERGENT ONSHORE FLOW
SIMILAR TO COASTAL FRONT...WHICH WOULD GIVE A SPECIFIC AREA
SEVERAL INCHES WITH VERY LITTLE ELSEWHERE. FOR NOW...HOLDING ONTO
THE IDEA OF A MOVING TROUGH WITH ACCUMS OF A COATING IN MOST
SPOTS. INLAND JUST LOOKS FOR MAINLY CLOUDY SKIES IN THIS TIME
FRAMEWITH A FEW FLURRIES.

MAY SEE A LITTLE BIT OF A BREAK ON TUE AS WEAK OFFSHORE SFC LOW
EXITS AND ALLOWS SOME RIDGING TO BUILD BACK IN FROM THE NE...THEN
WE START GETTING INTO THE EFFECTS OF THE IMPRESSIVE STORM SYSTEM
THAT RAPIDLY INTENSIFIES TO OUR WEST. PRECIP MOVES IN TUE
NIGHT...WHICH WILL BEGIN AS RAIN ALONG THE COAST...WITH EARLY LOWS
IN THE MID TO UPPER 30S. INLAND...PRECIP WILL START AS SNOW...AND
TRANSITIONS TO FREEZING RAIN OR RAIN LATE TUE NIGHT...AND
EVENTUALLY TRANSITION TO RAIN WED MORNING. THE HEAVY PRECIP WILL
MAINLY FALL AS RAIN WED AFTERNOON AND WED NIGHT. GFS QPF SEEMS
HIGH...AS IT MAY BE DEALING WITH CONVECTIVE SCALING ISSUES...AND
THE 1.5-2.5" OF THE EURO SEEMS MORE REASONABLE ATTM...STRONG SE
FLOW DEVELOPS EAST OF THE OCCLUSION POINT WHICH CROSSES WRN NEW
ENGLAND WED NIGHT. WILL SEE STRONG LOW LEVEL SE JET DEVELOP ABOVE
THE INVERSION AROUND THIS TIME AS WELL...AND ALTHOUGH THE
INVERSION SHOULD PREVENT FULL MIXING...ESPECIALLY OVER
LAND...COULD SEE WIND GUSTS APPROACHING ADV LEVELS. HIGHS WED WILL
LKLY OCCUR LATE IN THE DAY WED OR WED EVE...AND WILL MAKE A RUN AT
50 IN SRN NH AND ALONG THE COAST.

SHARP BACK EDGE TO THE RAIN WILL CROSS THE REGION EARLY WED AND
RAIN SHOULD END FROM SW TO NE DURING THE MORNING AND EARLY
AFTERNOON...WITH SOME PARTIAL CLEARING POSSIBLE IN THE AFTERNOON.
GUSTY W-SW WINDS WILL DEVELOP BEHIND THE SYSTEM....BUT HIGHS WILL
STILL BE ABV NORMAL...IN THE 40S.

&&

.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
SHORT TERM...MVFR CONDITIONS WILL CONTINUE UNTIL ABOUT DAYBREAK
IN THE CT RIVER VALLEY AS LOW LEVEL MOISTURE HAS BECOME TRAPPED.
SHOULD SEE ALL AREAS RETURN TO VFR DURING THE DAY AND THEN MORE
MOISTURE WILL WORK ITS WAY INTO THE REGION AS LOW LEVEL WIND FLOW
TURNS ON SHORE. THIS WILL BRING SOME MVFR CEILING AND POSSIBLE
SOME LIGHT SNOW SHOWERS FROM SATURDAY EVENING THROUGH MONDAY.


LONG TERM...POSSIBLE PERIODS OF MVFR TO IFR AT COASTAL TERMINALS
SUN NIGHT INTO MONDAY AS INVERTED TROUGH DEVELOPS ACROSS THE GULF
OF ME. MVFR LIKELY TO HOLD TUE INTO TUE NIGHT...WITH LOWERING TO
IFR LATE TUE NIGHT AND WED IN RAIN...WITH INCREASING E-SE WINDS
LATE IN THE DAY WED.

&&

.MARINE...
SHORT TERM...WINDS AND SEAS WILL REMAIN BELOW SCA CONDITIONS THRU
SUNDAY.

LONG TERM...WATER REMAIN BLO SCA LVLS SUN NIGHT THROUGH TUE
NIGHT. STRONG LOW PRES TO THE WEST WILL SEE WINDS INCREASE TO
GALES WED AFTERNOON WITH BORDERLINE STORM FORCE WINDS POSSIBLE WED
NIGHT.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.

&&

$$
KISTNER/CEMPA



000
FXUS61 KGYX 201204
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
704 AM EST SAT DEC 20 2014

.SYNOPSIS...
WEAK HIGH PRESSURE MOVES ACROSS THE REGION THROUGH SATURDAY. THE
HIGH BUILDS OVER NORTHERN MAINE SUNDAY...ALLOWING THE FLOW TO TURN
ONSHORE. A WEAK WEATHER DISTURBANCE MAY TRIGGER SOME FLURRIES OR
LIGHT SNOW OVER SOUTHERN REGIONS LATER SUNDAY INTO MONDAY. A WEAK
AREA OF LOW PRESSURE WILL MOVE UP THE COAST TUESDAY...WITH A MORE
SIGNIFICANT SYSTEM GRADUALLY ORGANIZING WEDNESDAY...BEFORE MOVING
OVER THE GREAT LAKES. THIS COULD BRING WINDY CONDITIONS AND THE
POTENTIAL FOR HEAVY RAIN AROUND CHRISTMAS EVE INTO EARLY CHRISTMAS
MORNING.

&&

.NEAR TERM /THROUGH TONIGHT/...
7 AM UPDATE...SOME IMPRESSIVE RADIATIONAL COOLING ACROSS THE NORTH
THIS MORNING...WITH LOWS NOW DROPPING BELOW ZERO. UPDATED THE LOW
TEMPERATURE FORECAST BASED ON THE CURRENT OBS AND TRENDS...AS
GUIDANCE WAS OVER 10 DEGREES OFF IN MANY AREAS ACROSS THE NORTH.
STILL JUST A FEW CLOUDS HOLDING ON IN THE CT RIVER
VALLEY...OTHERWISE MOSTLY CLEAR SKIES ELSEWHERE. FORECAST IS STILL
ON TRACK FOR CLOUDS TO INCREASE THROUGH OUT THE DAY WITH LOW
STRATUS PUSHING IN FROM THE OCEAN AND FROM THE NORTH.

PREVIOUS DISCUSSION...
A WEAK SHORT WAVE IS CLEARLY VISIBLE ON
WATER VAPOR IMAGERY MOVING EAST ACROSS NY AS OF 3AM. OTHER THAN
THE CT RIVER VALLEY THE BULK OF THE CWA IS MOSTLY CLEAR. AS THE
SHORT WAVE APPROACHES WE SHOULD SEE NORTHEAST FLOW SWITCH AT 925MB
TO MORE ON SHORE EAST TO SOUTHEASTERLY FLOW. THIS WILL START TO
ADVECT LOW CLOUDS IN OFF THE OCEAN. LOW CLOUDS MOVING AROUND THE
SURFACE HIGH TO THE NORTH WILL ALSO START TO PUSH IN FROM THE
NORTHEAST. SO MOST OF THE AREA WILL GO FROM CLEAR TO MOSTLY
CLOUDY/OVERCAST SKIES BY THIS EVENING.

&&

.SHORT TERM /SUNDAY/...
LOW LEVEL ONSHORE FLOW BELOW THE RIDGE ALOFT WILL PUSH MOISTURE
INLAND. THE WEAK SHORT WAVE TROF WILL BE THE FOCUS AS IT CONTINUES
TO DRIFT EASTWARD ACROSS THE REGION LATE TONIGHT AND EARLY SUNDAY.
AN INVERTED TROUGH SETS UP AT THE SURFACE ACROSS THE FAR SOUTHERN
CWA. THIS COMBINED WITH THE SHORT WAVE SHOULD ALLOW ENOUGH
FORCING FOR ASCENT TO SATURATE UP TO 700MB. AS MENTIONED IN
YESTERDAY`S AFTERNOON FORECAST PACKAGE...THIS SETS UP A NICE
SEEDER-FEEDER PROCESS TO INCREASE THE SNOW SHOWER ACTIVITY ACROSS
SOUTHERN ZONES IN SOUTHEASTERN NEW HAMPSHIRE AND POSSIBLY COASTAL
YORK COUNTY. THERE IS GOOD MODEL AGREEMENT BETWEEN MESOSCALE AND
SYNOPTIC MODELS HINTING AT LIGHT QPF IN THESE AREAS...AND
ACCUMULATING SNOWFALL MAY BE POSSIBLE. USED A BLEND OF
NAM/GFS/ARW/NMM FOR POP AND QPF FORECAST.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
MEDIUM RANGE MODELS CONTINUE TO TRANSITION FROM A HIGHER WAVE
NUMBER TO A LOWER ONE NEXT WEEK WITH STRONG BLOCKING UPSTREAM AND
DOWNSTREAM AND MEAN TROUGH DEVELOPING ACROSS NRN TWO THIRDS OF
NOAM. THE TRANSITION PERIOD WILL MAKE FOR AN ACTIVE WX WEEK.
HOWEVER...WE LOOK TO STAY ON THE WARM SIDE OF THE TROUGH THROUGH
FRIDAY...WITH HIGHS RUNNING ABV NORMAL AND MAINLY RAIN.

BEST CHC FOR ANY ACCUMULATING SNOW IN THE EXTENDED WILL BE ALONG
THE COAST SUNDAY NIGHT INTO EARLY MONDAY AS MODELS INDICATING
DEVELOPMENT OF INVERTED TROUGH. NAM12/GFS IN FAIR AGREEMENT AS TO
TIMING AND LOCATION...DEVELOPING ALONG THE MID-COAST SUN
NIGHT...AND SHIFT WEST TOWARD THE NH AND SW ME COASTS DURING THE
DAY ON MONDAY. EURO TENDS TO HOLD THE QPF AROUND AND E OF
PENOBSCOT BAY UNTIL LATE MONDAY AND THEN SHIFTS IT EAST MONDAY
NIGHT. THE AGREEMENT BETWEEN THE NAM AND GFS THIS FAR OUT IS
INTERESTING...SINCE MODELS TEND TO NOT HANDLE THESE INVERTED
TROUGHS WELL UNTIL THEY IN THE 12-24 HOUR RANGE....BUT HAVE
GENERALLY FOLLOWED A NAM/GFS BLEND SUN NIGHT THRU MON NIGHT. QPF
WILL BE LIGHT AND SUN NIGHT IS THE BEST CHC FOR ANY ACCUMS AS
PRECIP WILL LKLY MIX WITH OR CHANGE TO RAIN DURING THE DAY
MONDAY...AND EVEN IF IT DOES STAY AS SNOW...WILL HAVE TOUGH TIME
ACCUMULATING. THE ONE THING TO WATCH FRO WITH INVERTED TROUGHS IS
IF IT LOCKS INTO ONE AREA...AND SETS UP CONVERGENT ONSHORE FLOW
SIMILAR TO COASTAL FRONT...WHICH WOULD GIVE A SPECIFIC AREA
SEVERAL INCHES WITH VERY LITTLE ELSEWHERE. FOR NOW...HOLDING ONTO
THE IDEA OF A MOVING TROUGH WITH ACCUMS OF A COATING IN MOST
SPOTS. INLAND JUST LOOKS FOR MAINLY CLOUDY SKIES IN THIS TIME
FRAMEWITH A FEW FLURRIES.

MAY SEE A LITTLE BIT OF A BREAK ON TUE AS WEAK OFFSHORE SFC LOW
EXITS AND ALLOWS SOME RIDGING TO BUILD BACK IN FROM THE NE...THEN
WE START GETTING INTO THE EFFECTS OF THE IMPRESSIVE STORM SYSTEM
THAT RAPIDLY INTENSIFIES TO OUR WEST. PRECIP MOVES IN TUE
NIGHT...WHICH WILL BEGIN AS RAIN ALONG THE COAST...WITH EARLY LOWS
IN THE MID TO UPPER 30S. INLAND...PRECIP WILL START AS SNOW...AND
TRANSITIONS TO FREEZING RAIN OR RAIN LATE TUE NIGHT...AND
EVENTUALLY TRANSITION TO RAIN WED MORNING. THE HEAVY PRECIP WILL
MAINLY FALL AS RAIN WED AFTERNOON AND WED NIGHT. GFS QPF SEEMS
HIGH...AS IT MAY BE DEALING WITH CONVECTIVE SCALING ISSUES...AND
THE 1.5-2.5" OF THE EURO SEEMS MORE REASONABLE ATTM...STRONG SE
FLOW DEVELOPS EAST OF THE OCCLUSION POINT WHICH CROSSES WRN NEW
ENGLAND WED NIGHT. WILL SEE STRONG LOW LEVEL SE JET DEVELOP ABOVE
THE INVERSION AROUND THIS TIME AS WELL...AND ALTHOUGH THE
INVERSION SHOULD PREVENT FULL MIXING...ESPECIALLY OVER
LAND...COULD SEE WIND GUSTS APPROACHING ADV LEVELS. HIGHS WED WILL
LKLY OCCUR LATE IN THE DAY WED OR WED EVE...AND WILL MAKE A RUN AT
50 IN SRN NH AND ALONG THE COAST.

SHARP BACK EDGE TO THE RAIN WILL CROSS THE REGION EARLY WED AND
RAIN SHOULD END FROM SW TO NE DURING THE MORNING AND EARLY
AFTERNOON...WITH SOME PARTIAL CLEARING POSSIBLE IN THE AFTERNOON.
GUSTY W-SW WINDS WILL DEVELOP BEHIND THE SYSTEM....BUT HIGHS WILL
STILL BE ABV NORMAL...IN THE 40S.

&&

.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
SHORT TERM...MVFR CONDITIONS WILL CONTINUE UNTIL ABOUT DAYBREAK
IN THE CT RIVER VALLEY AS LOW LEVEL MOISTURE HAS BECOME TRAPPED.
SHOULD SEE ALL AREAS RETURN TO VFR DURING THE DAY AND THEN MORE
MOISTURE WILL WORK ITS WAY INTO THE REGION AS LOW LEVEL WIND FLOW
TURNS ON SHORE. THIS WILL BRING SOME MVFR CEILING AND POSSIBLE
SOME LIGHT SNOW SHOWERS FROM SATURDAY EVENING THROUGH MONDAY.


LONG TERM...POSSIBLE PERIODS OF MVFR TO IFR AT COASTAL TERMINALS
SUN NIGHT INTO MONDAY AS INVERTED TROUGH DEVELOPS ACROSS THE GULF
OF ME. MVFR LIKELY TO HOLD TUE INTO TUE NIGHT...WITH LOWERING TO
IFR LATE TUE NIGHT AND WED IN RAIN...WITH INCREASING E-SE WINDS
LATE IN THE DAY WED.

&&

.MARINE...
SHORT TERM...WINDS AND SEAS WILL REMAIN BELOW SCA CONDITIONS THRU
SUNDAY.

LONG TERM...WATER REMAIN BLO SCA LVLS SUN NIGHT THROUGH TUE
NIGHT. STRONG LOW PRES TO THE WEST WILL SEE WINDS INCREASE TO
GALES WED AFTERNOON WITH BORDERLINE STORM FORCE WINDS POSSIBLE WED
NIGHT.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.

&&

$$
KISTNER/CEMPA



000
FXUS61 KBOX 201204
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
704 AM EST SAT DEC 20 2014

.SYNOPSIS...
SCATTERED SNOW SHOWERS WILL GRADUALLY OVERSPREAD THE REGION FROM
EAST TO WEST LATER TODAY INTO SUNDAY.  THE EXCEPTION WILL BE THE
IMMEDIATE SOUTHEAST NEW ENGLAND COAST...WHERE IT SHOULD BECOME MILD
ENOUGH FOR SCATTERED RAIN SHOWERS. WEAK LOW PRESSURE WILL PASS SOUTH
OF NEW ENGLAND...BRINGING ANOTHER PERIOD OF PRECIPITATION. A MUCH
STRONGER STORM PASSING WEST OF NEW ENGLAND WILL BRING HEAVY
RAINFALL...GUSTY WINDS AND COASTAL FLOODING CONCERNS TO THE REGION
WEDNESDAY INTO WEDNESDAY EVENING. DRY BUT VERY WINDY CONDITIONS
FOLLOW FOR CHRISTMAS DAY INTO FRIDAY.

&&

.NEAR TERM /UNTIL NOON TODAY/...

700 AM UPDATE...

TREND IN THE FORECAST REMAINS ON TRACK. NORTHEASTERLY FLOW ONSHORE
HAS LEAD TO A FEW FLURRIES ACROSS THE CAPE AND PLYMOUTH COUNTY.
SHOULD BE LOCALIZED TO THIS REGION AS THE FLOW OVER BOSTON AND
TAUNTON ARE NORTHWEST. OTHERWISE CLOUDS ARE SLOWLY STARTING TO
FILL.

PREVIOUS DISCUSSION...

AN APPROACHING SHORTWAVE HAS ALLOWED WINDS JUST OFF THE GROUND TO
BECOME EASTERLY.  THIS WAS ALLOWING LOW CLOUDS TO BACK INTO
SOUTHEAST MA/RI EARLY THIS MORNING.  EXPECT THIS TREND TO CONTINUE
WITH LOW CLOUDS CONTINUING TO GRADUALLY WORK FURTHER WEST...BUT M.
SUNNY SKIES SHOULD PREVAIL THIS MORNING IN NORTHWEST MA.
MEANWHILE...SOME OCEAN EFFECT FLURRIES/LIGHT SNOW SHOWERS MAY
DEVELOP ACROSS PLYMOUTH COUNTY AND ONTO THE CAPE/ISLANDS THIS
MORNING.

&&

.SHORT TERM /NOON TODAY THROUGH 6 PM SUNDAY/...
THIS AFTERNOON AND TONIGHT...

INTERESTING MESOSCALE SETUP AS AN INVERTED TROUGH COMBINES WITH SOME
OCEAN ENHANCEMENT.  APPROACHING UPPER LEVEL SHORTWAVE WILL ALLOW FOR
EASTERLY FLOW JUST OFF THE GROUND.  THIS COMBINED WITH NORTHEAST
SURFACE WINDS WILL ALLOW LOW LEVEL OF THE ATMOSPHERE TO MOISTEN.
SOUNDINGS ACROSS EASTERN NEW ENGLAND BECOME SATURATED ALL THE WAY UP
TO THE -9C LAYER JUST ABOVE 850 MB.  THIS IS FAVORABLE FOR SOME
DECENT SNOWGROWTH...ITS JUST LOWER IN THE ATMOSPHERE THAN WE
TYPICALLY SEE WITH MORE SYNOPTIC SNOW EVENTS.  WHILE THIS IS NOT A
TRUE OCEAN EFFECT EVENT...DELTA T VALUES FROM THE MIXED LAYER TO THE
OCEAN ARE AROUND 15C.  THEREFORE...EXPECT SOME OCEAN ENHANCEMENT.

TIMING:

WHILE FLURRIES/LIGHT SNOW SHOWERS MAY OCCUR ACROSS FAR SOUTHEAST NEW
ENGLAND THIS MORNING.  THE MORE SUBSTANTIAL  PRECIPITATION SHOULD
OVERSPREAD PLYMOUTH COUNTY AS WELL AS THE CAPE AND ISLANDS THIS
AFTERNOON.  GIVEN EASTERLY FLOW JUST OFF THE GROUND...EXPECT SNOW
SHOWERS TO OVERSPREAD MOST OF EASTERN NEW ENGLAND THIS EVENING AS
LOW LEVELS MOISTEN.  IN FACT...SHOULD SEE AT LEAST SOME SCATTERED
SNOW SHOWERS AFFECT EVEN OUR FAR WESTERN ZONES.

PTYPE:

MAINLY SNOW FOR ALL BUT PORTIONS OF COASTAL PLYMOUTH COUNTY AND ONTO
THE CAPE/ISLANDS.  A SUBTLE COASTAL FRONT LOOKS TO SETUP ACROSS
SOUTHEAST COASTAL PLYMOUTH COUNTY.  PTYPE WILL BE SNOW TO THE
NORTHWEST OF THIS REGION...BUT ENOUGH MILD AIR SHOULD COME IN OFF
THE OCEAN FOR A CHANGE TO RAIN SHOWERS SOUTHEAST OF THIS REGION.
NOT EXPECTING THE POSITION OF THIS SUBTLE BOUNDARY TO CHANGE MUCH
THROUGH SUNDAY MORNING.

SNOW ACCUMULATIONS:

WE ARE GENERALLY LOOKING AT A COATING TO 2 INCHES OF SNOW ACROSS
MOST OF THE REGION.  THE MAIN FOCUS FOR 1 TO 2 INCHES WILL BE ACROSS
PORTIONS OF SOUTHEAST MA...AWAY FROM THE SOUTHEAST PLYMOUTH COUNTY
COAST.  ALSO...THE WORCESTER HILLS INTO NORTHWEST RHODE ISLAND MIGHT
BE ANOTHER AREA AS A RESULT OF THE SUBTLE UPSLOPE COMPONENT TO THE
WIND.  YOU CAN ACTUALLY SEE THAT IN SOME OF THE HIGH RESOLUTION
MODEL GUIDANCE.

THERE IS ONE AREA TO WATCH IN PARTICULAR...FROM NORTHWEST PLYMOUTH
COUNTY AND INTO NORFOLK COUNTY BASED ON MESOSCALE MODELS AND PATTERN
RECOGNITION.  WOULD NOT BE SURPRISED TO SEE VERY LOCALIZED 3 TO 4
INCH SNOW AMOUNTS...GIVEN SOME OCEAN ENHANCEMENT AND A LITTLE FOCUS
ON THE COASTAL FRONT.  WILL TRY TO HIGHLIGHT THIS AREA IN OUR
SNOWFALL AND PROBABILISTIC  GRAPHICS.

SUNDAY...

SCATTERED SNOW SHOWERS WILL CONTINUE DURING THE MORNING WITH MOIST
EASTERLY FLOW IN THE LOW LEVELS. AGAIN...PTYPE WILL BE SNOW EXCEPT
ACROSS SOUTHEAST PLYMOUTH COUNTY/CAPE AND ISLANDS WHERE BOUNDARY
LAYER WILL PROBABLY BE WARM ENOUGH FOR RAIN SHOWERS.  WHILE SOME
LIGHT PRECIPITATION MAY LINGER INTO SUNDAY AFTERNOON...EXPECT A
DECREASE IN AREAL COVERAGE THROUGH THE AFTERNOON AS LOW LEVEL LIFT
WEAKENS.  IT WILL REMAIN CLOUDY THOUGH WITH TEMPS IN THE 30S.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
HIGHLIGHTS...

* INVERTED TROUGH WILL BRING RAIN/SNOW SHOWERS TO THE MASS EAST
  COASTLINE MONDAY INTO TUES MORNING.
* WEAK WAVE OF LOW PRESSURE MON NIGHT/TUESDAY COULD BRING WINTRY
  MIX TO INTERIOR
* ANOMALOUS SYSTEM ACROSS THE GREAT LAKES WILL BRING HEAVY
  RAIN...GUSTY WINDS AND COASTAL FLOODING CONCERNS AROUND CHRISTMAS
  EVE

OVERVIEW...

OVERALL 00Z GUIDANCE IS IN AGREEMENT SYNOPTICALLY WITH ISSUES ON
TIMING AND SMALLER SCALE FEATURES. IT REMAINS EVIDENT THAT AN
AMPLIFIED MID-UPPER LEVEL TROUGH AND PCPN FOCUSING LEAD SURFACE
LOW/FRONTAL SYSTEM WILL STEADILY PROGRESS TO THE EAST-CENTRAL U.S.
TUE AS EMBEDDED IMPULSES DIG TO THE LEE OF AN AMPLIFIED ERN
PACIFIC/WEST COAST RIDGE ALOFT. THE SUPPORTING AND INCREASINGLY
NEGATIVE-TILT TROUGH ALOFT WORKS OVER THE ERN US AND OUT THROUGH THE
NERN STATES INTO DAYS 4/5 WED/THU.  MODELS/ENSEMBLES HAVE BEEN
FAIRLY CONSISTENT ON THIS AMPLIFIED PATTERN AND THE MOST RECENT
GEFS/ECMWF ENSEMBLE GUIDANCE SHOW GOOD CORRELATION TO NEXT THURSDAY.

HIGH PRESSURE AND UPPER LEVEL RIDGE OVER THE REGION WILL BEGIN TO
EXIT BY MONDAY. AT THE SURFACE APPEARS ANOTHER INVERTED
TROUGH/ONSHORE FLOW WILL YIELD TO PRECIP ALONG THE MASS COASTLINE ON
MONDAY. ASIDE FROM THIS QUICK MESOSCALE EVENT THE MAIN FOCUS IS ON
THE LONGWAVE DIGGING TROUGH OVER THE CENTRAL CONUS WHICH WILL PUSH A
FEW SHORTWAVES THROUGH THE FLOW. FIRST ONE DEVELOPS A WEAK WAVE
MOVING TOWARDS THE REGION LATE MONDAY INTO TUESDAY. THERE IS STILL
SOME UNCERTAINTY WITH THE LOCATION/STRENGTH OF THIS SYSTEM BUT
APPEARS THAT THERE IS THE POSSIBILITY OF A SNOW/WINTRY MIX IN THE
INTERIOR. AS THIS SYSTEM DEPARTS AN ANOMALOUS LOW OVER THE GREAT
LAKES WILL DEVELOP A SECONDARY LOW JUST WEST OF SOUTHERN NEW ENGLAND
     PER ENSEMBLE GUIDANCE. STILL A SOME SPREAD BUT IF THIS DOUBLE LOW
DOES DEVELOP THEN THE RAIN AND WIND ASPECT OF THE SYSTEM
INCREASES...DETAILS BELOW. STILL NEED TO WORK OUT MINOR DETAILS WITH
THIS PARTICULAR SYSTEM BUT WITH 3 TO 4 STANDARD DEVIATIONS AWAY AND
GENERAL MODEL AGREEMENT HAVE HIGH CONFIDENCE THIS SYSTEM WILL IMPACT
SOUTHERN NEW ENGLAND.

DETAILS...

SUNDAY NIGHT INTO TUESDAY...MODERATE CONFIDENCE.

HIGH PRESSURE AND UPPER LEVEL RIDGE WILL BEGIN TO MOVE OFFSHORE AS
DIGGING TROUGH BEGINS TO SET-UP OVER THE CENTRAL CONUS. APPEARS
ANOTHER MESO-SCALE INVERTED TROUGH WILL SET UP ON MONDAY AND LAST
INTO EARLY TUESDAY MORNING. GUIDANCE SHOWS THAT RAIN/SNOW SHOWERS
WILL DEVELOP ALONG THE MASS EAST COASTLINE THANKS TO ONSHORE
EASTERLY FLOW. APPEARS THE COLUMN WILL SATURATE PER BUFKIT SOUNDINGS
AND SOUTHERLY FLOW ALOFT. BOTH THE NAM AND GFS SHOW QPF MAKING IT
ONSHORE DURING THIS TIME FRAME. HOWEVER THE EC IS SLIGHTLY SLOWER
AND KEEP THE BULK OF THE PRECIP JUST OFFSHORE. ADD A CHANCE OF POPS
DUE TO THE NAM/GFS MODEL CONTINUITY.

BY LATE MONDAY NIGHT INTO TUESDAY A SOUTHERN BRANCH STORM SYSTEM
FORMS ALONG THE SE COAST AND TAKES A TRACK OFF THE MID ATLANTIC
COAST. THIS SYSTEM GETS CAUGHT UP WITH THE OVERALL LARGE SCALE
AMPLIFICATION OF THE UPPER AIR PATTERN. THERE IS DECENT WARM
ADVECTION WITH COLD AIR DAMMING ACROSS THE INTERIOR. BIGGEST
QUESTION WILL BE IS THERE ENOUGH MOISTURE FOR PRECIP DURING THIS
TIME FRAME. IF PRECIP OVERRUNS THEN COULD SEE FREEZING RAIN/DRIZZLE
ACROSS THE INTERIOR LATE MONDAY INTO TUESDAY MORNING. DURING THE DAY
ON TUESDAY...GOOD AMOUNT OF WARM AIR WILL PUSH SURFACE TEMPS ABOVE
FREEZING ALLOWING FOR ANY PRECIP TO BE MORE OF THE LIQUID VARIETY
AHEAD OF THE CHRISTMAS EVE STORM. HOWEVER GUIDANCE IS ALWAYS TOO
FAST IN SCOURING TEMPS OUT ESP ACROSS THE CT VALLEY SO WE WILL NEED
TO MONITOR THIS CLOSELY...ESP DUE TO LIGHT WINDS AND THE HIGH IN
EASTERN CANADA.

WE COULD ALSO SEE SOME MINOR COASTAL FLOODING CONCERNS ON TUESDAY. SEE
BELOW FOR MORE DETAILS.

WEDNESDAY INTO THURSDAY...HIGH CONFIDENCE IN SYSTEM LOW CONFIDENCE
ON DETAILS.

STRONG ANOMALOUS SYSTEM WILL STRENGTHEN OVER THE GREAT
LAKES...DEVELOPING A POTENTIAL SECONDARY SURFACE LOW JUST WEST OF
SOUTHERN NEW ENGLAND. STILL A LOT OF DETAILS TO WORK OUT AS THIS
SYSTEM IS STILL 5 DAYS AWAY...HOWEVER ENSEMBLES CONTINUE TO SHOW
STRONG AGREEMENT SO HAVE INCREASING CONFIDENCE THAT A POTENT STORM
WILL OCCUR. LATEST 00Z GUIDANCE SHOWS THAT MOST PRECIP WILL BE
LIQUID WITH A DEEP SUBTROPICAL CONNECTION BACK ACROSS THE GULF OF
MEXICO...PW ANOMALIES FORECAST TO RISE BETWEEN +3 TO +4. CURRENT
PWATS ARE PROGGED ABOVE 1.6 INCHES SO HAVE CONTINUED THE CATEGORICAL
POPS. TEMPERATURES WILL BE WELL ABOVE AVERAGE...IN FACT WE MAY BE
CLOSE AT BREAKING RECORD HIGH TEMPS IF TEMPS WARM TO 60F OR ABOVE ON
CHRISTMAS EVE.  AS THE SYSTEM WRAPS UP INTO CANADA...COLD AIR
ADVECTION SHOULD CIRCULATE AROUND AND BEGIN A TRANSITION FROM
SOUTHWEST TO NORTHEAST IN TURNING P-TYPE TO SNOW. HOWEVER LATEST
GUIDANCE DOES SHOW A QUICK MOVING DRY SLOT SO SNOWFALL WILL STRUGGLE
DUE TO LACK OF MOISTURE.

THIS SYSTEM IS QUITE POTENT SO WE WILL NEED TO WATCH FOR POTENTIAL
HAZARDS. CURRENTLY THINK THAT WE COULD POSSIBLE URBAN FLOODING
ISSUES AS MODELS PROGGED WELL OVER 1.5 INCHES OF QPF. LATEST EC EVEN
SHOWS 2.5 INCHES OF QPF IS POSSIBLE. THE GEFS SHOW A MOISTURE FLUX
AT 850 MB BEING 4 TO 5 STANDARD DEVIATIONS AWAY...AND WITH THE
TROPICAL CONNECTION AND STRONG SOUTHERLY FLOW COULD SEE HIGHER
AMOUNTS DUE TO TOPOGRAPHY ENHANCEMENTS. RAIN FALL RECORDS MAY FALL
IF EVERYTHING FALLS INTO PLACE.

ALSO BELIEVE THAT WE MAY SEE SOME WIND ISSUES WITH THIS SYSTEM.
GUIDANCE RIGHT NOW IS SHOWING A 45 TO 55 KT JET AT 925 MB...HOWEVER
IT WILL BE HARD TO BREAK THE INVERSION WITH THE SOUTHERLY FLOW.
RIGHT NOW BELIEVE THAT WIND ADVISORIES MAY BE NEEDED BUT IF THIS
SYSTEM STRENGTHEN EVEN MORE SO A STRONGER JET IS POSSIBLE.

CONTINUED THE MENTIONED OF ISOLATED THUNDER IN THE FORECAST PER PREV
FORECASTER SUGGESTION. BELIEVE IT COULD BE POSSIBLE AS SOUTHERN NEW
ENGLAND WILL BE IN THE WARM SECTOR...WITH THE ANOMALOUS JET AND
SHOWALTERS CLOSE TO ZERO.

FRIDAY...LOW CONFIDENCE.

ONCE UPPER LEVEL LOW MOVES INTO SOUTHERN CANADA...EXPECT A RATHER
FAST UPPER W FLOW IN PLACE. MAY SEE LEFTOVER SNOW SHOWERS BUT TEMPS
WILL FALL BACK CLOSE TO SEASONAL NORMS.

&&

.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH SUNDAY/...

700 AM UPDATE...

TODAY...MODERATE CONFIDENCE.  MVFR CIGS WILL CONTINUE TO OVERSPREAD
EASTERN NEW ENGLAND THIS MORNING AND EVENTUALLY INTO THE INTERIOR
THIS AFTERNOON.  SCATTERED PRECIPITATION WILL OVERSPREAD
SOUTHEAST MA/CAPE/ISLANDS THIS AFTERNOON.  PTYPE MAINLY SNOW SHOWERS
NORTHWEST OF THE SOUTHEAST PLYMOUTH COUNTY COAST AND RAIN SHOWERS
SOUTHEAST OF THAT REGION. LOCALIZED IFR CONDITIONS POSSIBLE JUST
INLAND FROM THE SOUTHEAST NEW ENGLAND COAST...WHERE PTYPE IS SNOW.

TONIGHT AND SUNDAY...MODERATE CONFIDENCE.  MVFR CONDITIONS DOMINATE
IN LOWER CLOUDS AND SCATTERED PRECIPITATION.  LOCALIZED IFR
CONDITIONS POSSIBLE WITH THE BEST CHANCE IN SNOW SHOWERS.
PRECIPITATION AFFECTS MAINLY EASTERN NEW ENGLAND BUT STILL SOME
SCATTERED ACTIVITY ACROSS WESTERN NEW ENGLAND. PTYPE MAINLY SNOW
SHOWERS NORTHWEST OF THE SOUTHEAST PLYMOUTH COUNTY COAST...WITH RAIN
SHOWERS SOUTHEAST OF THAT REGION.

KBOS TERMINAL...MODERATE CONFIDENCE IN TAF.  SNOW SHOWERS MAY ARRIVE
TOWARDS 00Z THIS EVENING.

KBDL TERMINAL...MODERATE CONFIDENCE IN TAF.

OUTLOOK...SUNDAY NIGHT THROUGH WEDNESDAY...

MONDAY INTO TUESDAY...MODERATE CONFIDENCE. EXPECT MOSTLY
VFR...ISOLATED MVFR ALONG THE MASS EAST COASTLINE IN RAIN/SNOW
SHOWERS.

TUESDAY NIGHT INTO WEDNESDAY...MODERATE CONFIDENCE. CONDITIONS WILL
BE DETERIORATING AS HEAVY DOWNPOURS...ISO THUNDER AND GUSTY SOUTHERLY
WINDS MOVE INTO THE REGION BY WEDNESDAY. COULD SEE MVFR TO IFR
CONDITIONS IN CIGS AND VSBYS.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /TODAY THROUGH SUNDAY/...HIGH CONFIDENCE.

HIGH PRESSURE ACROSS QUEBEC WILL RESULT IN PERSISTENT NORTHEAST
WINDS ACROSS THE WATERS THROUGH THE WEEKEND.  WIND GUSTS UP TO 20
KNOTS WITH SEAS BETWEEN 2 AND 4 FEET ARE EXPECTED FOR MOST
WATERS...SO NO HEADLINES PLANNED. THERE IS A LOW PROBABILITY THAT A
BRIEF SURGE OF NORTHEAST WIND GUSTS NEAR 25 KNOTS WITH MARGINAL 5
FOOT SEAS COULD AFFECT OUR NORTHERN WATERS LATE TONIGHT INTO SUN
MORNING...BUT NOT CONFIDENT ENOUGH TO ISSUE ANY HEADLINES AT THIS
POINT.

OUTLOOK...SUNDAY NIGHT INTO WEDNESDAY...MODERATE TO HIGH
CONFIDENCE.

SUNDAY INTO MONDAY. CONTINUOUS NORTHEAST FLOW WILL KEEP SEAS CHOPPY.
LINGERING NORTHEAST SWELL MAY BUMP SEAS ABOVE 5FT ESP ACROSS THE
NORTHEASTERN WATERS. SCA MAY BE NEEDED...BUT LOWER CONFIDENCE.

TUESDAY INTO WEDNESDAY...NE WINDS WILL INCREASE...GUSTING TO 30 KT
TUE THEN SHIFT TO SE GUSTING TO 30-35 KT WED...HIGHEST ON THE OUTER
WATERS. SEAS BUILD UP TO 7-11 FT BY WED. GALES WILL BE NEEDED.

&&

.TIDES/COASTAL FLOODING...
HIGH ASTRONOMICAL TIDES WILL OCCUR TUESDAY THROUGH THURSDAY. BREAKING
IT DOWN...ON TUESDAY HIGH TIDE AT BOSTON WILL BE 11.6 FT. THERE WILL
BE ONSHORE FLOW DURING THIS HIGH TIDE ALLOWING FOR MINOR SPLASHOVER.
IF WIND GUSTS INCREASE THEN COULD POSSIBLE SEE MINOR COASTAL
FLOODING.

ON WEDNESDAY...WINDS WILL SWITCH TO A MORE SOUTHEASTERLY FLOW DURING
THE DAY AND INCREASE QUICKLY FROM APPROACHING SYSTEM AND DESCENT
PRESSURE FALLS. WEDNESDAY AFTERNOON HIGH TIDE IN BOSTON IS 11.7 FT
AND WITH ANY STRENGTH ON THE EASTERLY WIND FLOW WILL PUSH THE TIDE
OVER. RIGHT NOW BELIEVE MINOR COASTAL FLOODING IS POSSIBLE ALONG THE
EAST COASTLINE. HOWEVER WEDNESDAY EVENING...THE WIND GOES IN A MORE
SOUTHERLY DIRECTION AND HIGH TIDE IN PROVIDENCE WILL BE 5.2 FT. 925
MB LLJ STRENGTHENS TO 50-60 KTS WHICH COULD PUSH A DESCENT SURGE UP
ALONG THE SOUTH COAST DURING THE TIME OF HIGH TIDE. THINKING THAT
MINOR COASTAL FLOODING COULD OCCUR BUT CANNOT RULE OUT MODERATE
ALONG THE SOUTH COAST...ESP IF LLJ STRENGTHENS EVEN MORE.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...FRANK/DUNTEN
NEAR TERM...FRANK/DUNTEN
SHORT TERM...FRANK
LONG TERM...DUNTEN
AVIATION...FRANK/DUNTEN
MARINE...FRANK/DUNTEN
TIDES/COASTAL FLOODING...



000
FXUS61 KGYX 201204
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
704 AM EST SAT DEC 20 2014

.SYNOPSIS...
WEAK HIGH PRESSURE MOVES ACROSS THE REGION THROUGH SATURDAY. THE
HIGH BUILDS OVER NORTHERN MAINE SUNDAY...ALLOWING THE FLOW TO TURN
ONSHORE. A WEAK WEATHER DISTURBANCE MAY TRIGGER SOME FLURRIES OR
LIGHT SNOW OVER SOUTHERN REGIONS LATER SUNDAY INTO MONDAY. A WEAK
AREA OF LOW PRESSURE WILL MOVE UP THE COAST TUESDAY...WITH A MORE
SIGNIFICANT SYSTEM GRADUALLY ORGANIZING WEDNESDAY...BEFORE MOVING
OVER THE GREAT LAKES. THIS COULD BRING WINDY CONDITIONS AND THE
POTENTIAL FOR HEAVY RAIN AROUND CHRISTMAS EVE INTO EARLY CHRISTMAS
MORNING.

&&

.NEAR TERM /THROUGH TONIGHT/...
7 AM UPDATE...SOME IMPRESSIVE RADIATIONAL COOLING ACROSS THE NORTH
THIS MORNING...WITH LOWS NOW DROPPING BELOW ZERO. UPDATED THE LOW
TEMPERATURE FORECAST BASED ON THE CURRENT OBS AND TRENDS...AS
GUIDANCE WAS OVER 10 DEGREES OFF IN MANY AREAS ACROSS THE NORTH.
STILL JUST A FEW CLOUDS HOLDING ON IN THE CT RIVER
VALLEY...OTHERWISE MOSTLY CLEAR SKIES ELSEWHERE. FORECAST IS STILL
ON TRACK FOR CLOUDS TO INCREASE THROUGH OUT THE DAY WITH LOW
STRATUS PUSHING IN FROM THE OCEAN AND FROM THE NORTH.

PREVIOUS DISCUSSION...
A WEAK SHORT WAVE IS CLEARLY VISIBLE ON
WATER VAPOR IMAGERY MOVING EAST ACROSS NY AS OF 3AM. OTHER THAN
THE CT RIVER VALLEY THE BULK OF THE CWA IS MOSTLY CLEAR. AS THE
SHORT WAVE APPROACHES WE SHOULD SEE NORTHEAST FLOW SWITCH AT 925MB
TO MORE ON SHORE EAST TO SOUTHEASTERLY FLOW. THIS WILL START TO
ADVECT LOW CLOUDS IN OFF THE OCEAN. LOW CLOUDS MOVING AROUND THE
SURFACE HIGH TO THE NORTH WILL ALSO START TO PUSH IN FROM THE
NORTHEAST. SO MOST OF THE AREA WILL GO FROM CLEAR TO MOSTLY
CLOUDY/OVERCAST SKIES BY THIS EVENING.

&&

.SHORT TERM /SUNDAY/...
LOW LEVEL ONSHORE FLOW BELOW THE RIDGE ALOFT WILL PUSH MOISTURE
INLAND. THE WEAK SHORT WAVE TROF WILL BE THE FOCUS AS IT CONTINUES
TO DRIFT EASTWARD ACROSS THE REGION LATE TONIGHT AND EARLY SUNDAY.
AN INVERTED TROUGH SETS UP AT THE SURFACE ACROSS THE FAR SOUTHERN
CWA. THIS COMBINED WITH THE SHORT WAVE SHOULD ALLOW ENOUGH
FORCING FOR ASCENT TO SATURATE UP TO 700MB. AS MENTIONED IN
YESTERDAY`S AFTERNOON FORECAST PACKAGE...THIS SETS UP A NICE
SEEDER-FEEDER PROCESS TO INCREASE THE SNOW SHOWER ACTIVITY ACROSS
SOUTHERN ZONES IN SOUTHEASTERN NEW HAMPSHIRE AND POSSIBLY COASTAL
YORK COUNTY. THERE IS GOOD MODEL AGREEMENT BETWEEN MESOSCALE AND
SYNOPTIC MODELS HINTING AT LIGHT QPF IN THESE AREAS...AND
ACCUMULATING SNOWFALL MAY BE POSSIBLE. USED A BLEND OF
NAM/GFS/ARW/NMM FOR POP AND QPF FORECAST.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
MEDIUM RANGE MODELS CONTINUE TO TRANSITION FROM A HIGHER WAVE
NUMBER TO A LOWER ONE NEXT WEEK WITH STRONG BLOCKING UPSTREAM AND
DOWNSTREAM AND MEAN TROUGH DEVELOPING ACROSS NRN TWO THIRDS OF
NOAM. THE TRANSITION PERIOD WILL MAKE FOR AN ACTIVE WX WEEK.
HOWEVER...WE LOOK TO STAY ON THE WARM SIDE OF THE TROUGH THROUGH
FRIDAY...WITH HIGHS RUNNING ABV NORMAL AND MAINLY RAIN.

BEST CHC FOR ANY ACCUMULATING SNOW IN THE EXTENDED WILL BE ALONG
THE COAST SUNDAY NIGHT INTO EARLY MONDAY AS MODELS INDICATING
DEVELOPMENT OF INVERTED TROUGH. NAM12/GFS IN FAIR AGREEMENT AS TO
TIMING AND LOCATION...DEVELOPING ALONG THE MID-COAST SUN
NIGHT...AND SHIFT WEST TOWARD THE NH AND SW ME COASTS DURING THE
DAY ON MONDAY. EURO TENDS TO HOLD THE QPF AROUND AND E OF
PENOBSCOT BAY UNTIL LATE MONDAY AND THEN SHIFTS IT EAST MONDAY
NIGHT. THE AGREEMENT BETWEEN THE NAM AND GFS THIS FAR OUT IS
INTERESTING...SINCE MODELS TEND TO NOT HANDLE THESE INVERTED
TROUGHS WELL UNTIL THEY IN THE 12-24 HOUR RANGE....BUT HAVE
GENERALLY FOLLOWED A NAM/GFS BLEND SUN NIGHT THRU MON NIGHT. QPF
WILL BE LIGHT AND SUN NIGHT IS THE BEST CHC FOR ANY ACCUMS AS
PRECIP WILL LKLY MIX WITH OR CHANGE TO RAIN DURING THE DAY
MONDAY...AND EVEN IF IT DOES STAY AS SNOW...WILL HAVE TOUGH TIME
ACCUMULATING. THE ONE THING TO WATCH FRO WITH INVERTED TROUGHS IS
IF IT LOCKS INTO ONE AREA...AND SETS UP CONVERGENT ONSHORE FLOW
SIMILAR TO COASTAL FRONT...WHICH WOULD GIVE A SPECIFIC AREA
SEVERAL INCHES WITH VERY LITTLE ELSEWHERE. FOR NOW...HOLDING ONTO
THE IDEA OF A MOVING TROUGH WITH ACCUMS OF A COATING IN MOST
SPOTS. INLAND JUST LOOKS FOR MAINLY CLOUDY SKIES IN THIS TIME
FRAMEWITH A FEW FLURRIES.

MAY SEE A LITTLE BIT OF A BREAK ON TUE AS WEAK OFFSHORE SFC LOW
EXITS AND ALLOWS SOME RIDGING TO BUILD BACK IN FROM THE NE...THEN
WE START GETTING INTO THE EFFECTS OF THE IMPRESSIVE STORM SYSTEM
THAT RAPIDLY INTENSIFIES TO OUR WEST. PRECIP MOVES IN TUE
NIGHT...WHICH WILL BEGIN AS RAIN ALONG THE COAST...WITH EARLY LOWS
IN THE MID TO UPPER 30S. INLAND...PRECIP WILL START AS SNOW...AND
TRANSITIONS TO FREEZING RAIN OR RAIN LATE TUE NIGHT...AND
EVENTUALLY TRANSITION TO RAIN WED MORNING. THE HEAVY PRECIP WILL
MAINLY FALL AS RAIN WED AFTERNOON AND WED NIGHT. GFS QPF SEEMS
HIGH...AS IT MAY BE DEALING WITH CONVECTIVE SCALING ISSUES...AND
THE 1.5-2.5" OF THE EURO SEEMS MORE REASONABLE ATTM...STRONG SE
FLOW DEVELOPS EAST OF THE OCCLUSION POINT WHICH CROSSES WRN NEW
ENGLAND WED NIGHT. WILL SEE STRONG LOW LEVEL SE JET DEVELOP ABOVE
THE INVERSION AROUND THIS TIME AS WELL...AND ALTHOUGH THE
INVERSION SHOULD PREVENT FULL MIXING...ESPECIALLY OVER
LAND...COULD SEE WIND GUSTS APPROACHING ADV LEVELS. HIGHS WED WILL
LKLY OCCUR LATE IN THE DAY WED OR WED EVE...AND WILL MAKE A RUN AT
50 IN SRN NH AND ALONG THE COAST.

SHARP BACK EDGE TO THE RAIN WILL CROSS THE REGION EARLY WED AND
RAIN SHOULD END FROM SW TO NE DURING THE MORNING AND EARLY
AFTERNOON...WITH SOME PARTIAL CLEARING POSSIBLE IN THE AFTERNOON.
GUSTY W-SW WINDS WILL DEVELOP BEHIND THE SYSTEM....BUT HIGHS WILL
STILL BE ABV NORMAL...IN THE 40S.

&&

.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
SHORT TERM...MVFR CONDITIONS WILL CONTINUE UNTIL ABOUT DAYBREAK
IN THE CT RIVER VALLEY AS LOW LEVEL MOISTURE HAS BECOME TRAPPED.
SHOULD SEE ALL AREAS RETURN TO VFR DURING THE DAY AND THEN MORE
MOISTURE WILL WORK ITS WAY INTO THE REGION AS LOW LEVEL WIND FLOW
TURNS ON SHORE. THIS WILL BRING SOME MVFR CEILING AND POSSIBLE
SOME LIGHT SNOW SHOWERS FROM SATURDAY EVENING THROUGH MONDAY.


LONG TERM...POSSIBLE PERIODS OF MVFR TO IFR AT COASTAL TERMINALS
SUN NIGHT INTO MONDAY AS INVERTED TROUGH DEVELOPS ACROSS THE GULF
OF ME. MVFR LIKELY TO HOLD TUE INTO TUE NIGHT...WITH LOWERING TO
IFR LATE TUE NIGHT AND WED IN RAIN...WITH INCREASING E-SE WINDS
LATE IN THE DAY WED.

&&

.MARINE...
SHORT TERM...WINDS AND SEAS WILL REMAIN BELOW SCA CONDITIONS THRU
SUNDAY.

LONG TERM...WATER REMAIN BLO SCA LVLS SUN NIGHT THROUGH TUE
NIGHT. STRONG LOW PRES TO THE WEST WILL SEE WINDS INCREASE TO
GALES WED AFTERNOON WITH BORDERLINE STORM FORCE WINDS POSSIBLE WED
NIGHT.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.

&&

$$
KISTNER/CEMPA



000
FXUS61 KGYX 201204
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
704 AM EST SAT DEC 20 2014

.SYNOPSIS...
WEAK HIGH PRESSURE MOVES ACROSS THE REGION THROUGH SATURDAY. THE
HIGH BUILDS OVER NORTHERN MAINE SUNDAY...ALLOWING THE FLOW TO TURN
ONSHORE. A WEAK WEATHER DISTURBANCE MAY TRIGGER SOME FLURRIES OR
LIGHT SNOW OVER SOUTHERN REGIONS LATER SUNDAY INTO MONDAY. A WEAK
AREA OF LOW PRESSURE WILL MOVE UP THE COAST TUESDAY...WITH A MORE
SIGNIFICANT SYSTEM GRADUALLY ORGANIZING WEDNESDAY...BEFORE MOVING
OVER THE GREAT LAKES. THIS COULD BRING WINDY CONDITIONS AND THE
POTENTIAL FOR HEAVY RAIN AROUND CHRISTMAS EVE INTO EARLY CHRISTMAS
MORNING.

&&

.NEAR TERM /THROUGH TONIGHT/...
7 AM UPDATE...SOME IMPRESSIVE RADIATIONAL COOLING ACROSS THE NORTH
THIS MORNING...WITH LOWS NOW DROPPING BELOW ZERO. UPDATED THE LOW
TEMPERATURE FORECAST BASED ON THE CURRENT OBS AND TRENDS...AS
GUIDANCE WAS OVER 10 DEGREES OFF IN MANY AREAS ACROSS THE NORTH.
STILL JUST A FEW CLOUDS HOLDING ON IN THE CT RIVER
VALLEY...OTHERWISE MOSTLY CLEAR SKIES ELSEWHERE. FORECAST IS STILL
ON TRACK FOR CLOUDS TO INCREASE THROUGH OUT THE DAY WITH LOW
STRATUS PUSHING IN FROM THE OCEAN AND FROM THE NORTH.

PREVIOUS DISCUSSION...
A WEAK SHORT WAVE IS CLEARLY VISIBLE ON
WATER VAPOR IMAGERY MOVING EAST ACROSS NY AS OF 3AM. OTHER THAN
THE CT RIVER VALLEY THE BULK OF THE CWA IS MOSTLY CLEAR. AS THE
SHORT WAVE APPROACHES WE SHOULD SEE NORTHEAST FLOW SWITCH AT 925MB
TO MORE ON SHORE EAST TO SOUTHEASTERLY FLOW. THIS WILL START TO
ADVECT LOW CLOUDS IN OFF THE OCEAN. LOW CLOUDS MOVING AROUND THE
SURFACE HIGH TO THE NORTH WILL ALSO START TO PUSH IN FROM THE
NORTHEAST. SO MOST OF THE AREA WILL GO FROM CLEAR TO MOSTLY
CLOUDY/OVERCAST SKIES BY THIS EVENING.

&&

.SHORT TERM /SUNDAY/...
LOW LEVEL ONSHORE FLOW BELOW THE RIDGE ALOFT WILL PUSH MOISTURE
INLAND. THE WEAK SHORT WAVE TROF WILL BE THE FOCUS AS IT CONTINUES
TO DRIFT EASTWARD ACROSS THE REGION LATE TONIGHT AND EARLY SUNDAY.
AN INVERTED TROUGH SETS UP AT THE SURFACE ACROSS THE FAR SOUTHERN
CWA. THIS COMBINED WITH THE SHORT WAVE SHOULD ALLOW ENOUGH
FORCING FOR ASCENT TO SATURATE UP TO 700MB. AS MENTIONED IN
YESTERDAY`S AFTERNOON FORECAST PACKAGE...THIS SETS UP A NICE
SEEDER-FEEDER PROCESS TO INCREASE THE SNOW SHOWER ACTIVITY ACROSS
SOUTHERN ZONES IN SOUTHEASTERN NEW HAMPSHIRE AND POSSIBLY COASTAL
YORK COUNTY. THERE IS GOOD MODEL AGREEMENT BETWEEN MESOSCALE AND
SYNOPTIC MODELS HINTING AT LIGHT QPF IN THESE AREAS...AND
ACCUMULATING SNOWFALL MAY BE POSSIBLE. USED A BLEND OF
NAM/GFS/ARW/NMM FOR POP AND QPF FORECAST.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
MEDIUM RANGE MODELS CONTINUE TO TRANSITION FROM A HIGHER WAVE
NUMBER TO A LOWER ONE NEXT WEEK WITH STRONG BLOCKING UPSTREAM AND
DOWNSTREAM AND MEAN TROUGH DEVELOPING ACROSS NRN TWO THIRDS OF
NOAM. THE TRANSITION PERIOD WILL MAKE FOR AN ACTIVE WX WEEK.
HOWEVER...WE LOOK TO STAY ON THE WARM SIDE OF THE TROUGH THROUGH
FRIDAY...WITH HIGHS RUNNING ABV NORMAL AND MAINLY RAIN.

BEST CHC FOR ANY ACCUMULATING SNOW IN THE EXTENDED WILL BE ALONG
THE COAST SUNDAY NIGHT INTO EARLY MONDAY AS MODELS INDICATING
DEVELOPMENT OF INVERTED TROUGH. NAM12/GFS IN FAIR AGREEMENT AS TO
TIMING AND LOCATION...DEVELOPING ALONG THE MID-COAST SUN
NIGHT...AND SHIFT WEST TOWARD THE NH AND SW ME COASTS DURING THE
DAY ON MONDAY. EURO TENDS TO HOLD THE QPF AROUND AND E OF
PENOBSCOT BAY UNTIL LATE MONDAY AND THEN SHIFTS IT EAST MONDAY
NIGHT. THE AGREEMENT BETWEEN THE NAM AND GFS THIS FAR OUT IS
INTERESTING...SINCE MODELS TEND TO NOT HANDLE THESE INVERTED
TROUGHS WELL UNTIL THEY IN THE 12-24 HOUR RANGE....BUT HAVE
GENERALLY FOLLOWED A NAM/GFS BLEND SUN NIGHT THRU MON NIGHT. QPF
WILL BE LIGHT AND SUN NIGHT IS THE BEST CHC FOR ANY ACCUMS AS
PRECIP WILL LKLY MIX WITH OR CHANGE TO RAIN DURING THE DAY
MONDAY...AND EVEN IF IT DOES STAY AS SNOW...WILL HAVE TOUGH TIME
ACCUMULATING. THE ONE THING TO WATCH FRO WITH INVERTED TROUGHS IS
IF IT LOCKS INTO ONE AREA...AND SETS UP CONVERGENT ONSHORE FLOW
SIMILAR TO COASTAL FRONT...WHICH WOULD GIVE A SPECIFIC AREA
SEVERAL INCHES WITH VERY LITTLE ELSEWHERE. FOR NOW...HOLDING ONTO
THE IDEA OF A MOVING TROUGH WITH ACCUMS OF A COATING IN MOST
SPOTS. INLAND JUST LOOKS FOR MAINLY CLOUDY SKIES IN THIS TIME
FRAMEWITH A FEW FLURRIES.

MAY SEE A LITTLE BIT OF A BREAK ON TUE AS WEAK OFFSHORE SFC LOW
EXITS AND ALLOWS SOME RIDGING TO BUILD BACK IN FROM THE NE...THEN
WE START GETTING INTO THE EFFECTS OF THE IMPRESSIVE STORM SYSTEM
THAT RAPIDLY INTENSIFIES TO OUR WEST. PRECIP MOVES IN TUE
NIGHT...WHICH WILL BEGIN AS RAIN ALONG THE COAST...WITH EARLY LOWS
IN THE MID TO UPPER 30S. INLAND...PRECIP WILL START AS SNOW...AND
TRANSITIONS TO FREEZING RAIN OR RAIN LATE TUE NIGHT...AND
EVENTUALLY TRANSITION TO RAIN WED MORNING. THE HEAVY PRECIP WILL
MAINLY FALL AS RAIN WED AFTERNOON AND WED NIGHT. GFS QPF SEEMS
HIGH...AS IT MAY BE DEALING WITH CONVECTIVE SCALING ISSUES...AND
THE 1.5-2.5" OF THE EURO SEEMS MORE REASONABLE ATTM...STRONG SE
FLOW DEVELOPS EAST OF THE OCCLUSION POINT WHICH CROSSES WRN NEW
ENGLAND WED NIGHT. WILL SEE STRONG LOW LEVEL SE JET DEVELOP ABOVE
THE INVERSION AROUND THIS TIME AS WELL...AND ALTHOUGH THE
INVERSION SHOULD PREVENT FULL MIXING...ESPECIALLY OVER
LAND...COULD SEE WIND GUSTS APPROACHING ADV LEVELS. HIGHS WED WILL
LKLY OCCUR LATE IN THE DAY WED OR WED EVE...AND WILL MAKE A RUN AT
50 IN SRN NH AND ALONG THE COAST.

SHARP BACK EDGE TO THE RAIN WILL CROSS THE REGION EARLY WED AND
RAIN SHOULD END FROM SW TO NE DURING THE MORNING AND EARLY
AFTERNOON...WITH SOME PARTIAL CLEARING POSSIBLE IN THE AFTERNOON.
GUSTY W-SW WINDS WILL DEVELOP BEHIND THE SYSTEM....BUT HIGHS WILL
STILL BE ABV NORMAL...IN THE 40S.

&&

.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
SHORT TERM...MVFR CONDITIONS WILL CONTINUE UNTIL ABOUT DAYBREAK
IN THE CT RIVER VALLEY AS LOW LEVEL MOISTURE HAS BECOME TRAPPED.
SHOULD SEE ALL AREAS RETURN TO VFR DURING THE DAY AND THEN MORE
MOISTURE WILL WORK ITS WAY INTO THE REGION AS LOW LEVEL WIND FLOW
TURNS ON SHORE. THIS WILL BRING SOME MVFR CEILING AND POSSIBLE
SOME LIGHT SNOW SHOWERS FROM SATURDAY EVENING THROUGH MONDAY.


LONG TERM...POSSIBLE PERIODS OF MVFR TO IFR AT COASTAL TERMINALS
SUN NIGHT INTO MONDAY AS INVERTED TROUGH DEVELOPS ACROSS THE GULF
OF ME. MVFR LIKELY TO HOLD TUE INTO TUE NIGHT...WITH LOWERING TO
IFR LATE TUE NIGHT AND WED IN RAIN...WITH INCREASING E-SE WINDS
LATE IN THE DAY WED.

&&

.MARINE...
SHORT TERM...WINDS AND SEAS WILL REMAIN BELOW SCA CONDITIONS THRU
SUNDAY.

LONG TERM...WATER REMAIN BLO SCA LVLS SUN NIGHT THROUGH TUE
NIGHT. STRONG LOW PRES TO THE WEST WILL SEE WINDS INCREASE TO
GALES WED AFTERNOON WITH BORDERLINE STORM FORCE WINDS POSSIBLE WED
NIGHT.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.

&&

$$
KISTNER/CEMPA



000
FXUS61 KBOX 201204
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
704 AM EST SAT DEC 20 2014

.SYNOPSIS...
SCATTERED SNOW SHOWERS WILL GRADUALLY OVERSPREAD THE REGION FROM
EAST TO WEST LATER TODAY INTO SUNDAY.  THE EXCEPTION WILL BE THE
IMMEDIATE SOUTHEAST NEW ENGLAND COAST...WHERE IT SHOULD BECOME MILD
ENOUGH FOR SCATTERED RAIN SHOWERS. WEAK LOW PRESSURE WILL PASS SOUTH
OF NEW ENGLAND...BRINGING ANOTHER PERIOD OF PRECIPITATION. A MUCH
STRONGER STORM PASSING WEST OF NEW ENGLAND WILL BRING HEAVY
RAINFALL...GUSTY WINDS AND COASTAL FLOODING CONCERNS TO THE REGION
WEDNESDAY INTO WEDNESDAY EVENING. DRY BUT VERY WINDY CONDITIONS
FOLLOW FOR CHRISTMAS DAY INTO FRIDAY.

&&

.NEAR TERM /UNTIL NOON TODAY/...

700 AM UPDATE...

TREND IN THE FORECAST REMAINS ON TRACK. NORTHEASTERLY FLOW ONSHORE
HAS LEAD TO A FEW FLURRIES ACROSS THE CAPE AND PLYMOUTH COUNTY.
SHOULD BE LOCALIZED TO THIS REGION AS THE FLOW OVER BOSTON AND
TAUNTON ARE NORTHWEST. OTHERWISE CLOUDS ARE SLOWLY STARTING TO
FILL.

PREVIOUS DISCUSSION...

AN APPROACHING SHORTWAVE HAS ALLOWED WINDS JUST OFF THE GROUND TO
BECOME EASTERLY.  THIS WAS ALLOWING LOW CLOUDS TO BACK INTO
SOUTHEAST MA/RI EARLY THIS MORNING.  EXPECT THIS TREND TO CONTINUE
WITH LOW CLOUDS CONTINUING TO GRADUALLY WORK FURTHER WEST...BUT M.
SUNNY SKIES SHOULD PREVAIL THIS MORNING IN NORTHWEST MA.
MEANWHILE...SOME OCEAN EFFECT FLURRIES/LIGHT SNOW SHOWERS MAY
DEVELOP ACROSS PLYMOUTH COUNTY AND ONTO THE CAPE/ISLANDS THIS
MORNING.

&&

.SHORT TERM /NOON TODAY THROUGH 6 PM SUNDAY/...
THIS AFTERNOON AND TONIGHT...

INTERESTING MESOSCALE SETUP AS AN INVERTED TROUGH COMBINES WITH SOME
OCEAN ENHANCEMENT.  APPROACHING UPPER LEVEL SHORTWAVE WILL ALLOW FOR
EASTERLY FLOW JUST OFF THE GROUND.  THIS COMBINED WITH NORTHEAST
SURFACE WINDS WILL ALLOW LOW LEVEL OF THE ATMOSPHERE TO MOISTEN.
SOUNDINGS ACROSS EASTERN NEW ENGLAND BECOME SATURATED ALL THE WAY UP
TO THE -9C LAYER JUST ABOVE 850 MB.  THIS IS FAVORABLE FOR SOME
DECENT SNOWGROWTH...ITS JUST LOWER IN THE ATMOSPHERE THAN WE
TYPICALLY SEE WITH MORE SYNOPTIC SNOW EVENTS.  WHILE THIS IS NOT A
TRUE OCEAN EFFECT EVENT...DELTA T VALUES FROM THE MIXED LAYER TO THE
OCEAN ARE AROUND 15C.  THEREFORE...EXPECT SOME OCEAN ENHANCEMENT.

TIMING:

WHILE FLURRIES/LIGHT SNOW SHOWERS MAY OCCUR ACROSS FAR SOUTHEAST NEW
ENGLAND THIS MORNING.  THE MORE SUBSTANTIAL  PRECIPITATION SHOULD
OVERSPREAD PLYMOUTH COUNTY AS WELL AS THE CAPE AND ISLANDS THIS
AFTERNOON.  GIVEN EASTERLY FLOW JUST OFF THE GROUND...EXPECT SNOW
SHOWERS TO OVERSPREAD MOST OF EASTERN NEW ENGLAND THIS EVENING AS
LOW LEVELS MOISTEN.  IN FACT...SHOULD SEE AT LEAST SOME SCATTERED
SNOW SHOWERS AFFECT EVEN OUR FAR WESTERN ZONES.

PTYPE:

MAINLY SNOW FOR ALL BUT PORTIONS OF COASTAL PLYMOUTH COUNTY AND ONTO
THE CAPE/ISLANDS.  A SUBTLE COASTAL FRONT LOOKS TO SETUP ACROSS
SOUTHEAST COASTAL PLYMOUTH COUNTY.  PTYPE WILL BE SNOW TO THE
NORTHWEST OF THIS REGION...BUT ENOUGH MILD AIR SHOULD COME IN OFF
THE OCEAN FOR A CHANGE TO RAIN SHOWERS SOUTHEAST OF THIS REGION.
NOT EXPECTING THE POSITION OF THIS SUBTLE BOUNDARY TO CHANGE MUCH
THROUGH SUNDAY MORNING.

SNOW ACCUMULATIONS:

WE ARE GENERALLY LOOKING AT A COATING TO 2 INCHES OF SNOW ACROSS
MOST OF THE REGION.  THE MAIN FOCUS FOR 1 TO 2 INCHES WILL BE ACROSS
PORTIONS OF SOUTHEAST MA...AWAY FROM THE SOUTHEAST PLYMOUTH COUNTY
COAST.  ALSO...THE WORCESTER HILLS INTO NORTHWEST RHODE ISLAND MIGHT
BE ANOTHER AREA AS A RESULT OF THE SUBTLE UPSLOPE COMPONENT TO THE
WIND.  YOU CAN ACTUALLY SEE THAT IN SOME OF THE HIGH RESOLUTION
MODEL GUIDANCE.

THERE IS ONE AREA TO WATCH IN PARTICULAR...FROM NORTHWEST PLYMOUTH
COUNTY AND INTO NORFOLK COUNTY BASED ON MESOSCALE MODELS AND PATTERN
RECOGNITION.  WOULD NOT BE SURPRISED TO SEE VERY LOCALIZED 3 TO 4
INCH SNOW AMOUNTS...GIVEN SOME OCEAN ENHANCEMENT AND A LITTLE FOCUS
ON THE COASTAL FRONT.  WILL TRY TO HIGHLIGHT THIS AREA IN OUR
SNOWFALL AND PROBABILISTIC  GRAPHICS.

SUNDAY...

SCATTERED SNOW SHOWERS WILL CONTINUE DURING THE MORNING WITH MOIST
EASTERLY FLOW IN THE LOW LEVELS. AGAIN...PTYPE WILL BE SNOW EXCEPT
ACROSS SOUTHEAST PLYMOUTH COUNTY/CAPE AND ISLANDS WHERE BOUNDARY
LAYER WILL PROBABLY BE WARM ENOUGH FOR RAIN SHOWERS.  WHILE SOME
LIGHT PRECIPITATION MAY LINGER INTO SUNDAY AFTERNOON...EXPECT A
DECREASE IN AREAL COVERAGE THROUGH THE AFTERNOON AS LOW LEVEL LIFT
WEAKENS.  IT WILL REMAIN CLOUDY THOUGH WITH TEMPS IN THE 30S.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
HIGHLIGHTS...

* INVERTED TROUGH WILL BRING RAIN/SNOW SHOWERS TO THE MASS EAST
  COASTLINE MONDAY INTO TUES MORNING.
* WEAK WAVE OF LOW PRESSURE MON NIGHT/TUESDAY COULD BRING WINTRY
  MIX TO INTERIOR
* ANOMALOUS SYSTEM ACROSS THE GREAT LAKES WILL BRING HEAVY
  RAIN...GUSTY WINDS AND COASTAL FLOODING CONCERNS AROUND CHRISTMAS
  EVE

OVERVIEW...

OVERALL 00Z GUIDANCE IS IN AGREEMENT SYNOPTICALLY WITH ISSUES ON
TIMING AND SMALLER SCALE FEATURES. IT REMAINS EVIDENT THAT AN
AMPLIFIED MID-UPPER LEVEL TROUGH AND PCPN FOCUSING LEAD SURFACE
LOW/FRONTAL SYSTEM WILL STEADILY PROGRESS TO THE EAST-CENTRAL U.S.
TUE AS EMBEDDED IMPULSES DIG TO THE LEE OF AN AMPLIFIED ERN
PACIFIC/WEST COAST RIDGE ALOFT. THE SUPPORTING AND INCREASINGLY
NEGATIVE-TILT TROUGH ALOFT WORKS OVER THE ERN US AND OUT THROUGH THE
NERN STATES INTO DAYS 4/5 WED/THU.  MODELS/ENSEMBLES HAVE BEEN
FAIRLY CONSISTENT ON THIS AMPLIFIED PATTERN AND THE MOST RECENT
GEFS/ECMWF ENSEMBLE GUIDANCE SHOW GOOD CORRELATION TO NEXT THURSDAY.

HIGH PRESSURE AND UPPER LEVEL RIDGE OVER THE REGION WILL BEGIN TO
EXIT BY MONDAY. AT THE SURFACE APPEARS ANOTHER INVERTED
TROUGH/ONSHORE FLOW WILL YIELD TO PRECIP ALONG THE MASS COASTLINE ON
MONDAY. ASIDE FROM THIS QUICK MESOSCALE EVENT THE MAIN FOCUS IS ON
THE LONGWAVE DIGGING TROUGH OVER THE CENTRAL CONUS WHICH WILL PUSH A
FEW SHORTWAVES THROUGH THE FLOW. FIRST ONE DEVELOPS A WEAK WAVE
MOVING TOWARDS THE REGION LATE MONDAY INTO TUESDAY. THERE IS STILL
SOME UNCERTAINTY WITH THE LOCATION/STRENGTH OF THIS SYSTEM BUT
APPEARS THAT THERE IS THE POSSIBILITY OF A SNOW/WINTRY MIX IN THE
INTERIOR. AS THIS SYSTEM DEPARTS AN ANOMALOUS LOW OVER THE GREAT
LAKES WILL DEVELOP A SECONDARY LOW JUST WEST OF SOUTHERN NEW ENGLAND
     PER ENSEMBLE GUIDANCE. STILL A SOME SPREAD BUT IF THIS DOUBLE LOW
DOES DEVELOP THEN THE RAIN AND WIND ASPECT OF THE SYSTEM
INCREASES...DETAILS BELOW. STILL NEED TO WORK OUT MINOR DETAILS WITH
THIS PARTICULAR SYSTEM BUT WITH 3 TO 4 STANDARD DEVIATIONS AWAY AND
GENERAL MODEL AGREEMENT HAVE HIGH CONFIDENCE THIS SYSTEM WILL IMPACT
SOUTHERN NEW ENGLAND.

DETAILS...

SUNDAY NIGHT INTO TUESDAY...MODERATE CONFIDENCE.

HIGH PRESSURE AND UPPER LEVEL RIDGE WILL BEGIN TO MOVE OFFSHORE AS
DIGGING TROUGH BEGINS TO SET-UP OVER THE CENTRAL CONUS. APPEARS
ANOTHER MESO-SCALE INVERTED TROUGH WILL SET UP ON MONDAY AND LAST
INTO EARLY TUESDAY MORNING. GUIDANCE SHOWS THAT RAIN/SNOW SHOWERS
WILL DEVELOP ALONG THE MASS EAST COASTLINE THANKS TO ONSHORE
EASTERLY FLOW. APPEARS THE COLUMN WILL SATURATE PER BUFKIT SOUNDINGS
AND SOUTHERLY FLOW ALOFT. BOTH THE NAM AND GFS SHOW QPF MAKING IT
ONSHORE DURING THIS TIME FRAME. HOWEVER THE EC IS SLIGHTLY SLOWER
AND KEEP THE BULK OF THE PRECIP JUST OFFSHORE. ADD A CHANCE OF POPS
DUE TO THE NAM/GFS MODEL CONTINUITY.

BY LATE MONDAY NIGHT INTO TUESDAY A SOUTHERN BRANCH STORM SYSTEM
FORMS ALONG THE SE COAST AND TAKES A TRACK OFF THE MID ATLANTIC
COAST. THIS SYSTEM GETS CAUGHT UP WITH THE OVERALL LARGE SCALE
AMPLIFICATION OF THE UPPER AIR PATTERN. THERE IS DECENT WARM
ADVECTION WITH COLD AIR DAMMING ACROSS THE INTERIOR. BIGGEST
QUESTION WILL BE IS THERE ENOUGH MOISTURE FOR PRECIP DURING THIS
TIME FRAME. IF PRECIP OVERRUNS THEN COULD SEE FREEZING RAIN/DRIZZLE
ACROSS THE INTERIOR LATE MONDAY INTO TUESDAY MORNING. DURING THE DAY
ON TUESDAY...GOOD AMOUNT OF WARM AIR WILL PUSH SURFACE TEMPS ABOVE
FREEZING ALLOWING FOR ANY PRECIP TO BE MORE OF THE LIQUID VARIETY
AHEAD OF THE CHRISTMAS EVE STORM. HOWEVER GUIDANCE IS ALWAYS TOO
FAST IN SCOURING TEMPS OUT ESP ACROSS THE CT VALLEY SO WE WILL NEED
TO MONITOR THIS CLOSELY...ESP DUE TO LIGHT WINDS AND THE HIGH IN
EASTERN CANADA.

WE COULD ALSO SEE SOME MINOR COASTAL FLOODING CONCERNS ON TUESDAY. SEE
BELOW FOR MORE DETAILS.

WEDNESDAY INTO THURSDAY...HIGH CONFIDENCE IN SYSTEM LOW CONFIDENCE
ON DETAILS.

STRONG ANOMALOUS SYSTEM WILL STRENGTHEN OVER THE GREAT
LAKES...DEVELOPING A POTENTIAL SECONDARY SURFACE LOW JUST WEST OF
SOUTHERN NEW ENGLAND. STILL A LOT OF DETAILS TO WORK OUT AS THIS
SYSTEM IS STILL 5 DAYS AWAY...HOWEVER ENSEMBLES CONTINUE TO SHOW
STRONG AGREEMENT SO HAVE INCREASING CONFIDENCE THAT A POTENT STORM
WILL OCCUR. LATEST 00Z GUIDANCE SHOWS THAT MOST PRECIP WILL BE
LIQUID WITH A DEEP SUBTROPICAL CONNECTION BACK ACROSS THE GULF OF
MEXICO...PW ANOMALIES FORECAST TO RISE BETWEEN +3 TO +4. CURRENT
PWATS ARE PROGGED ABOVE 1.6 INCHES SO HAVE CONTINUED THE CATEGORICAL
POPS. TEMPERATURES WILL BE WELL ABOVE AVERAGE...IN FACT WE MAY BE
CLOSE AT BREAKING RECORD HIGH TEMPS IF TEMPS WARM TO 60F OR ABOVE ON
CHRISTMAS EVE.  AS THE SYSTEM WRAPS UP INTO CANADA...COLD AIR
ADVECTION SHOULD CIRCULATE AROUND AND BEGIN A TRANSITION FROM
SOUTHWEST TO NORTHEAST IN TURNING P-TYPE TO SNOW. HOWEVER LATEST
GUIDANCE DOES SHOW A QUICK MOVING DRY SLOT SO SNOWFALL WILL STRUGGLE
DUE TO LACK OF MOISTURE.

THIS SYSTEM IS QUITE POTENT SO WE WILL NEED TO WATCH FOR POTENTIAL
HAZARDS. CURRENTLY THINK THAT WE COULD POSSIBLE URBAN FLOODING
ISSUES AS MODELS PROGGED WELL OVER 1.5 INCHES OF QPF. LATEST EC EVEN
SHOWS 2.5 INCHES OF QPF IS POSSIBLE. THE GEFS SHOW A MOISTURE FLUX
AT 850 MB BEING 4 TO 5 STANDARD DEVIATIONS AWAY...AND WITH THE
TROPICAL CONNECTION AND STRONG SOUTHERLY FLOW COULD SEE HIGHER
AMOUNTS DUE TO TOPOGRAPHY ENHANCEMENTS. RAIN FALL RECORDS MAY FALL
IF EVERYTHING FALLS INTO PLACE.

ALSO BELIEVE THAT WE MAY SEE SOME WIND ISSUES WITH THIS SYSTEM.
GUIDANCE RIGHT NOW IS SHOWING A 45 TO 55 KT JET AT 925 MB...HOWEVER
IT WILL BE HARD TO BREAK THE INVERSION WITH THE SOUTHERLY FLOW.
RIGHT NOW BELIEVE THAT WIND ADVISORIES MAY BE NEEDED BUT IF THIS
SYSTEM STRENGTHEN EVEN MORE SO A STRONGER JET IS POSSIBLE.

CONTINUED THE MENTIONED OF ISOLATED THUNDER IN THE FORECAST PER PREV
FORECASTER SUGGESTION. BELIEVE IT COULD BE POSSIBLE AS SOUTHERN NEW
ENGLAND WILL BE IN THE WARM SECTOR...WITH THE ANOMALOUS JET AND
SHOWALTERS CLOSE TO ZERO.

FRIDAY...LOW CONFIDENCE.

ONCE UPPER LEVEL LOW MOVES INTO SOUTHERN CANADA...EXPECT A RATHER
FAST UPPER W FLOW IN PLACE. MAY SEE LEFTOVER SNOW SHOWERS BUT TEMPS
WILL FALL BACK CLOSE TO SEASONAL NORMS.

&&

.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH SUNDAY/...

700 AM UPDATE...

TODAY...MODERATE CONFIDENCE.  MVFR CIGS WILL CONTINUE TO OVERSPREAD
EASTERN NEW ENGLAND THIS MORNING AND EVENTUALLY INTO THE INTERIOR
THIS AFTERNOON.  SCATTERED PRECIPITATION WILL OVERSPREAD
SOUTHEAST MA/CAPE/ISLANDS THIS AFTERNOON.  PTYPE MAINLY SNOW SHOWERS
NORTHWEST OF THE SOUTHEAST PLYMOUTH COUNTY COAST AND RAIN SHOWERS
SOUTHEAST OF THAT REGION. LOCALIZED IFR CONDITIONS POSSIBLE JUST
INLAND FROM THE SOUTHEAST NEW ENGLAND COAST...WHERE PTYPE IS SNOW.

TONIGHT AND SUNDAY...MODERATE CONFIDENCE.  MVFR CONDITIONS DOMINATE
IN LOWER CLOUDS AND SCATTERED PRECIPITATION.  LOCALIZED IFR
CONDITIONS POSSIBLE WITH THE BEST CHANCE IN SNOW SHOWERS.
PRECIPITATION AFFECTS MAINLY EASTERN NEW ENGLAND BUT STILL SOME
SCATTERED ACTIVITY ACROSS WESTERN NEW ENGLAND. PTYPE MAINLY SNOW
SHOWERS NORTHWEST OF THE SOUTHEAST PLYMOUTH COUNTY COAST...WITH RAIN
SHOWERS SOUTHEAST OF THAT REGION.

KBOS TERMINAL...MODERATE CONFIDENCE IN TAF.  SNOW SHOWERS MAY ARRIVE
TOWARDS 00Z THIS EVENING.

KBDL TERMINAL...MODERATE CONFIDENCE IN TAF.

OUTLOOK...SUNDAY NIGHT THROUGH WEDNESDAY...

MONDAY INTO TUESDAY...MODERATE CONFIDENCE. EXPECT MOSTLY
VFR...ISOLATED MVFR ALONG THE MASS EAST COASTLINE IN RAIN/SNOW
SHOWERS.

TUESDAY NIGHT INTO WEDNESDAY...MODERATE CONFIDENCE. CONDITIONS WILL
BE DETERIORATING AS HEAVY DOWNPOURS...ISO THUNDER AND GUSTY SOUTHERLY
WINDS MOVE INTO THE REGION BY WEDNESDAY. COULD SEE MVFR TO IFR
CONDITIONS IN CIGS AND VSBYS.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /TODAY THROUGH SUNDAY/...HIGH CONFIDENCE.

HIGH PRESSURE ACROSS QUEBEC WILL RESULT IN PERSISTENT NORTHEAST
WINDS ACROSS THE WATERS THROUGH THE WEEKEND.  WIND GUSTS UP TO 20
KNOTS WITH SEAS BETWEEN 2 AND 4 FEET ARE EXPECTED FOR MOST
WATERS...SO NO HEADLINES PLANNED. THERE IS A LOW PROBABILITY THAT A
BRIEF SURGE OF NORTHEAST WIND GUSTS NEAR 25 KNOTS WITH MARGINAL 5
FOOT SEAS COULD AFFECT OUR NORTHERN WATERS LATE TONIGHT INTO SUN
MORNING...BUT NOT CONFIDENT ENOUGH TO ISSUE ANY HEADLINES AT THIS
POINT.

OUTLOOK...SUNDAY NIGHT INTO WEDNESDAY...MODERATE TO HIGH
CONFIDENCE.

SUNDAY INTO MONDAY. CONTINUOUS NORTHEAST FLOW WILL KEEP SEAS CHOPPY.
LINGERING NORTHEAST SWELL MAY BUMP SEAS ABOVE 5FT ESP ACROSS THE
NORTHEASTERN WATERS. SCA MAY BE NEEDED...BUT LOWER CONFIDENCE.

TUESDAY INTO WEDNESDAY...NE WINDS WILL INCREASE...GUSTING TO 30 KT
TUE THEN SHIFT TO SE GUSTING TO 30-35 KT WED...HIGHEST ON THE OUTER
WATERS. SEAS BUILD UP TO 7-11 FT BY WED. GALES WILL BE NEEDED.

&&

.TIDES/COASTAL FLOODING...
HIGH ASTRONOMICAL TIDES WILL OCCUR TUESDAY THROUGH THURSDAY. BREAKING
IT DOWN...ON TUESDAY HIGH TIDE AT BOSTON WILL BE 11.6 FT. THERE WILL
BE ONSHORE FLOW DURING THIS HIGH TIDE ALLOWING FOR MINOR SPLASHOVER.
IF WIND GUSTS INCREASE THEN COULD POSSIBLE SEE MINOR COASTAL
FLOODING.

ON WEDNESDAY...WINDS WILL SWITCH TO A MORE SOUTHEASTERLY FLOW DURING
THE DAY AND INCREASE QUICKLY FROM APPROACHING SYSTEM AND DESCENT
PRESSURE FALLS. WEDNESDAY AFTERNOON HIGH TIDE IN BOSTON IS 11.7 FT
AND WITH ANY STRENGTH ON THE EASTERLY WIND FLOW WILL PUSH THE TIDE
OVER. RIGHT NOW BELIEVE MINOR COASTAL FLOODING IS POSSIBLE ALONG THE
EAST COASTLINE. HOWEVER WEDNESDAY EVENING...THE WIND GOES IN A MORE
SOUTHERLY DIRECTION AND HIGH TIDE IN PROVIDENCE WILL BE 5.2 FT. 925
MB LLJ STRENGTHENS TO 50-60 KTS WHICH COULD PUSH A DESCENT SURGE UP
ALONG THE SOUTH COAST DURING THE TIME OF HIGH TIDE. THINKING THAT
MINOR COASTAL FLOODING COULD OCCUR BUT CANNOT RULE OUT MODERATE
ALONG THE SOUTH COAST...ESP IF LLJ STRENGTHENS EVEN MORE.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...FRANK/DUNTEN
NEAR TERM...FRANK/DUNTEN
SHORT TERM...FRANK
LONG TERM...DUNTEN
AVIATION...FRANK/DUNTEN
MARINE...FRANK/DUNTEN
TIDES/COASTAL FLOODING...



000
FXUS61 KGYX 201204
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
704 AM EST SAT DEC 20 2014

.SYNOPSIS...
WEAK HIGH PRESSURE MOVES ACROSS THE REGION THROUGH SATURDAY. THE
HIGH BUILDS OVER NORTHERN MAINE SUNDAY...ALLOWING THE FLOW TO TURN
ONSHORE. A WEAK WEATHER DISTURBANCE MAY TRIGGER SOME FLURRIES OR
LIGHT SNOW OVER SOUTHERN REGIONS LATER SUNDAY INTO MONDAY. A WEAK
AREA OF LOW PRESSURE WILL MOVE UP THE COAST TUESDAY...WITH A MORE
SIGNIFICANT SYSTEM GRADUALLY ORGANIZING WEDNESDAY...BEFORE MOVING
OVER THE GREAT LAKES. THIS COULD BRING WINDY CONDITIONS AND THE
POTENTIAL FOR HEAVY RAIN AROUND CHRISTMAS EVE INTO EARLY CHRISTMAS
MORNING.

&&

.NEAR TERM /THROUGH TONIGHT/...
7 AM UPDATE...SOME IMPRESSIVE RADIATIONAL COOLING ACROSS THE NORTH
THIS MORNING...WITH LOWS NOW DROPPING BELOW ZERO. UPDATED THE LOW
TEMPERATURE FORECAST BASED ON THE CURRENT OBS AND TRENDS...AS
GUIDANCE WAS OVER 10 DEGREES OFF IN MANY AREAS ACROSS THE NORTH.
STILL JUST A FEW CLOUDS HOLDING ON IN THE CT RIVER
VALLEY...OTHERWISE MOSTLY CLEAR SKIES ELSEWHERE. FORECAST IS STILL
ON TRACK FOR CLOUDS TO INCREASE THROUGH OUT THE DAY WITH LOW
STRATUS PUSHING IN FROM THE OCEAN AND FROM THE NORTH.

PREVIOUS DISCUSSION...
A WEAK SHORT WAVE IS CLEARLY VISIBLE ON
WATER VAPOR IMAGERY MOVING EAST ACROSS NY AS OF 3AM. OTHER THAN
THE CT RIVER VALLEY THE BULK OF THE CWA IS MOSTLY CLEAR. AS THE
SHORT WAVE APPROACHES WE SHOULD SEE NORTHEAST FLOW SWITCH AT 925MB
TO MORE ON SHORE EAST TO SOUTHEASTERLY FLOW. THIS WILL START TO
ADVECT LOW CLOUDS IN OFF THE OCEAN. LOW CLOUDS MOVING AROUND THE
SURFACE HIGH TO THE NORTH WILL ALSO START TO PUSH IN FROM THE
NORTHEAST. SO MOST OF THE AREA WILL GO FROM CLEAR TO MOSTLY
CLOUDY/OVERCAST SKIES BY THIS EVENING.

&&

.SHORT TERM /SUNDAY/...
LOW LEVEL ONSHORE FLOW BELOW THE RIDGE ALOFT WILL PUSH MOISTURE
INLAND. THE WEAK SHORT WAVE TROF WILL BE THE FOCUS AS IT CONTINUES
TO DRIFT EASTWARD ACROSS THE REGION LATE TONIGHT AND EARLY SUNDAY.
AN INVERTED TROUGH SETS UP AT THE SURFACE ACROSS THE FAR SOUTHERN
CWA. THIS COMBINED WITH THE SHORT WAVE SHOULD ALLOW ENOUGH
FORCING FOR ASCENT TO SATURATE UP TO 700MB. AS MENTIONED IN
YESTERDAY`S AFTERNOON FORECAST PACKAGE...THIS SETS UP A NICE
SEEDER-FEEDER PROCESS TO INCREASE THE SNOW SHOWER ACTIVITY ACROSS
SOUTHERN ZONES IN SOUTHEASTERN NEW HAMPSHIRE AND POSSIBLY COASTAL
YORK COUNTY. THERE IS GOOD MODEL AGREEMENT BETWEEN MESOSCALE AND
SYNOPTIC MODELS HINTING AT LIGHT QPF IN THESE AREAS...AND
ACCUMULATING SNOWFALL MAY BE POSSIBLE. USED A BLEND OF
NAM/GFS/ARW/NMM FOR POP AND QPF FORECAST.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
MEDIUM RANGE MODELS CONTINUE TO TRANSITION FROM A HIGHER WAVE
NUMBER TO A LOWER ONE NEXT WEEK WITH STRONG BLOCKING UPSTREAM AND
DOWNSTREAM AND MEAN TROUGH DEVELOPING ACROSS NRN TWO THIRDS OF
NOAM. THE TRANSITION PERIOD WILL MAKE FOR AN ACTIVE WX WEEK.
HOWEVER...WE LOOK TO STAY ON THE WARM SIDE OF THE TROUGH THROUGH
FRIDAY...WITH HIGHS RUNNING ABV NORMAL AND MAINLY RAIN.

BEST CHC FOR ANY ACCUMULATING SNOW IN THE EXTENDED WILL BE ALONG
THE COAST SUNDAY NIGHT INTO EARLY MONDAY AS MODELS INDICATING
DEVELOPMENT OF INVERTED TROUGH. NAM12/GFS IN FAIR AGREEMENT AS TO
TIMING AND LOCATION...DEVELOPING ALONG THE MID-COAST SUN
NIGHT...AND SHIFT WEST TOWARD THE NH AND SW ME COASTS DURING THE
DAY ON MONDAY. EURO TENDS TO HOLD THE QPF AROUND AND E OF
PENOBSCOT BAY UNTIL LATE MONDAY AND THEN SHIFTS IT EAST MONDAY
NIGHT. THE AGREEMENT BETWEEN THE NAM AND GFS THIS FAR OUT IS
INTERESTING...SINCE MODELS TEND TO NOT HANDLE THESE INVERTED
TROUGHS WELL UNTIL THEY IN THE 12-24 HOUR RANGE....BUT HAVE
GENERALLY FOLLOWED A NAM/GFS BLEND SUN NIGHT THRU MON NIGHT. QPF
WILL BE LIGHT AND SUN NIGHT IS THE BEST CHC FOR ANY ACCUMS AS
PRECIP WILL LKLY MIX WITH OR CHANGE TO RAIN DURING THE DAY
MONDAY...AND EVEN IF IT DOES STAY AS SNOW...WILL HAVE TOUGH TIME
ACCUMULATING. THE ONE THING TO WATCH FRO WITH INVERTED TROUGHS IS
IF IT LOCKS INTO ONE AREA...AND SETS UP CONVERGENT ONSHORE FLOW
SIMILAR TO COASTAL FRONT...WHICH WOULD GIVE A SPECIFIC AREA
SEVERAL INCHES WITH VERY LITTLE ELSEWHERE. FOR NOW...HOLDING ONTO
THE IDEA OF A MOVING TROUGH WITH ACCUMS OF A COATING IN MOST
SPOTS. INLAND JUST LOOKS FOR MAINLY CLOUDY SKIES IN THIS TIME
FRAMEWITH A FEW FLURRIES.

MAY SEE A LITTLE BIT OF A BREAK ON TUE AS WEAK OFFSHORE SFC LOW
EXITS AND ALLOWS SOME RIDGING TO BUILD BACK IN FROM THE NE...THEN
WE START GETTING INTO THE EFFECTS OF THE IMPRESSIVE STORM SYSTEM
THAT RAPIDLY INTENSIFIES TO OUR WEST. PRECIP MOVES IN TUE
NIGHT...WHICH WILL BEGIN AS RAIN ALONG THE COAST...WITH EARLY LOWS
IN THE MID TO UPPER 30S. INLAND...PRECIP WILL START AS SNOW...AND
TRANSITIONS TO FREEZING RAIN OR RAIN LATE TUE NIGHT...AND
EVENTUALLY TRANSITION TO RAIN WED MORNING. THE HEAVY PRECIP WILL
MAINLY FALL AS RAIN WED AFTERNOON AND WED NIGHT. GFS QPF SEEMS
HIGH...AS IT MAY BE DEALING WITH CONVECTIVE SCALING ISSUES...AND
THE 1.5-2.5" OF THE EURO SEEMS MORE REASONABLE ATTM...STRONG SE
FLOW DEVELOPS EAST OF THE OCCLUSION POINT WHICH CROSSES WRN NEW
ENGLAND WED NIGHT. WILL SEE STRONG LOW LEVEL SE JET DEVELOP ABOVE
THE INVERSION AROUND THIS TIME AS WELL...AND ALTHOUGH THE
INVERSION SHOULD PREVENT FULL MIXING...ESPECIALLY OVER
LAND...COULD SEE WIND GUSTS APPROACHING ADV LEVELS. HIGHS WED WILL
LKLY OCCUR LATE IN THE DAY WED OR WED EVE...AND WILL MAKE A RUN AT
50 IN SRN NH AND ALONG THE COAST.

SHARP BACK EDGE TO THE RAIN WILL CROSS THE REGION EARLY WED AND
RAIN SHOULD END FROM SW TO NE DURING THE MORNING AND EARLY
AFTERNOON...WITH SOME PARTIAL CLEARING POSSIBLE IN THE AFTERNOON.
GUSTY W-SW WINDS WILL DEVELOP BEHIND THE SYSTEM....BUT HIGHS WILL
STILL BE ABV NORMAL...IN THE 40S.

&&

.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
SHORT TERM...MVFR CONDITIONS WILL CONTINUE UNTIL ABOUT DAYBREAK
IN THE CT RIVER VALLEY AS LOW LEVEL MOISTURE HAS BECOME TRAPPED.
SHOULD SEE ALL AREAS RETURN TO VFR DURING THE DAY AND THEN MORE
MOISTURE WILL WORK ITS WAY INTO THE REGION AS LOW LEVEL WIND FLOW
TURNS ON SHORE. THIS WILL BRING SOME MVFR CEILING AND POSSIBLE
SOME LIGHT SNOW SHOWERS FROM SATURDAY EVENING THROUGH MONDAY.


LONG TERM...POSSIBLE PERIODS OF MVFR TO IFR AT COASTAL TERMINALS
SUN NIGHT INTO MONDAY AS INVERTED TROUGH DEVELOPS ACROSS THE GULF
OF ME. MVFR LIKELY TO HOLD TUE INTO TUE NIGHT...WITH LOWERING TO
IFR LATE TUE NIGHT AND WED IN RAIN...WITH INCREASING E-SE WINDS
LATE IN THE DAY WED.

&&

.MARINE...
SHORT TERM...WINDS AND SEAS WILL REMAIN BELOW SCA CONDITIONS THRU
SUNDAY.

LONG TERM...WATER REMAIN BLO SCA LVLS SUN NIGHT THROUGH TUE
NIGHT. STRONG LOW PRES TO THE WEST WILL SEE WINDS INCREASE TO
GALES WED AFTERNOON WITH BORDERLINE STORM FORCE WINDS POSSIBLE WED
NIGHT.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.

&&

$$
KISTNER/CEMPA



000
FXUS61 KGYX 201204
AFDGYX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
704 AM EST SAT DEC 20 2014

.SYNOPSIS...
WEAK HIGH PRESSURE MOVES ACROSS THE REGION THROUGH SATURDAY. THE
HIGH BUILDS OVER NORTHERN MAINE SUNDAY...ALLOWING THE FLOW TO TURN
ONSHORE. A WEAK WEATHER DISTURBANCE MAY TRIGGER SOME FLURRIES OR
LIGHT SNOW OVER SOUTHERN REGIONS LATER SUNDAY INTO MONDAY. A WEAK
AREA OF LOW PRESSURE WILL MOVE UP THE COAST TUESDAY...WITH A MORE
SIGNIFICANT SYSTEM GRADUALLY ORGANIZING WEDNESDAY...BEFORE MOVING
OVER THE GREAT LAKES. THIS COULD BRING WINDY CONDITIONS AND THE
POTENTIAL FOR HEAVY RAIN AROUND CHRISTMAS EVE INTO EARLY CHRISTMAS
MORNING.

&&

.NEAR TERM /THROUGH TONIGHT/...
7 AM UPDATE...SOME IMPRESSIVE RADIATIONAL COOLING ACROSS THE NORTH
THIS MORNING...WITH LOWS NOW DROPPING BELOW ZERO. UPDATED THE LOW
TEMPERATURE FORECAST BASED ON THE CURRENT OBS AND TRENDS...AS
GUIDANCE WAS OVER 10 DEGREES OFF IN MANY AREAS ACROSS THE NORTH.
STILL JUST A FEW CLOUDS HOLDING ON IN THE CT RIVER
VALLEY...OTHERWISE MOSTLY CLEAR SKIES ELSEWHERE. FORECAST IS STILL
ON TRACK FOR CLOUDS TO INCREASE THROUGH OUT THE DAY WITH LOW
STRATUS PUSHING IN FROM THE OCEAN AND FROM THE NORTH.

PREVIOUS DISCUSSION...
A WEAK SHORT WAVE IS CLEARLY VISIBLE ON
WATER VAPOR IMAGERY MOVING EAST ACROSS NY AS OF 3AM. OTHER THAN
THE CT RIVER VALLEY THE BULK OF THE CWA IS MOSTLY CLEAR. AS THE
SHORT WAVE APPROACHES WE SHOULD SEE NORTHEAST FLOW SWITCH AT 925MB
TO MORE ON SHORE EAST TO SOUTHEASTERLY FLOW. THIS WILL START TO
ADVECT LOW CLOUDS IN OFF THE OCEAN. LOW CLOUDS MOVING AROUND THE
SURFACE HIGH TO THE NORTH WILL ALSO START TO PUSH IN FROM THE
NORTHEAST. SO MOST OF THE AREA WILL GO FROM CLEAR TO MOSTLY
CLOUDY/OVERCAST SKIES BY THIS EVENING.

&&

.SHORT TERM /SUNDAY/...
LOW LEVEL ONSHORE FLOW BELOW THE RIDGE ALOFT WILL PUSH MOISTURE
INLAND. THE WEAK SHORT WAVE TROF WILL BE THE FOCUS AS IT CONTINUES
TO DRIFT EASTWARD ACROSS THE REGION LATE TONIGHT AND EARLY SUNDAY.
AN INVERTED TROUGH SETS UP AT THE SURFACE ACROSS THE FAR SOUTHERN
CWA. THIS COMBINED WITH THE SHORT WAVE SHOULD ALLOW ENOUGH
FORCING FOR ASCENT TO SATURATE UP TO 700MB. AS MENTIONED IN
YESTERDAY`S AFTERNOON FORECAST PACKAGE...THIS SETS UP A NICE
SEEDER-FEEDER PROCESS TO INCREASE THE SNOW SHOWER ACTIVITY ACROSS
SOUTHERN ZONES IN SOUTHEASTERN NEW HAMPSHIRE AND POSSIBLY COASTAL
YORK COUNTY. THERE IS GOOD MODEL AGREEMENT BETWEEN MESOSCALE AND
SYNOPTIC MODELS HINTING AT LIGHT QPF IN THESE AREAS...AND
ACCUMULATING SNOWFALL MAY BE POSSIBLE. USED A BLEND OF
NAM/GFS/ARW/NMM FOR POP AND QPF FORECAST.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
MEDIUM RANGE MODELS CONTINUE TO TRANSITION FROM A HIGHER WAVE
NUMBER TO A LOWER ONE NEXT WEEK WITH STRONG BLOCKING UPSTREAM AND
DOWNSTREAM AND MEAN TROUGH DEVELOPING ACROSS NRN TWO THIRDS OF
NOAM. THE TRANSITION PERIOD WILL MAKE FOR AN ACTIVE WX WEEK.
HOWEVER...WE LOOK TO STAY ON THE WARM SIDE OF THE TROUGH THROUGH
FRIDAY...WITH HIGHS RUNNING ABV NORMAL AND MAINLY RAIN.

BEST CHC FOR ANY ACCUMULATING SNOW IN THE EXTENDED WILL BE ALONG
THE COAST SUNDAY NIGHT INTO EARLY MONDAY AS MODELS INDICATING
DEVELOPMENT OF INVERTED TROUGH. NAM12/GFS IN FAIR AGREEMENT AS TO
TIMING AND LOCATION...DEVELOPING ALONG THE MID-COAST SUN
NIGHT...AND SHIFT WEST TOWARD THE NH AND SW ME COASTS DURING THE
DAY ON MONDAY. EURO TENDS TO HOLD THE QPF AROUND AND E OF
PENOBSCOT BAY UNTIL LATE MONDAY AND THEN SHIFTS IT EAST MONDAY
NIGHT. THE AGREEMENT BETWEEN THE NAM AND GFS THIS FAR OUT IS
INTERESTING...SINCE MODELS TEND TO NOT HANDLE THESE INVERTED
TROUGHS WELL UNTIL THEY IN THE 12-24 HOUR RANGE....BUT HAVE
GENERALLY FOLLOWED A NAM/GFS BLEND SUN NIGHT THRU MON NIGHT. QPF
WILL BE LIGHT AND SUN NIGHT IS THE BEST CHC FOR ANY ACCUMS AS
PRECIP WILL LKLY MIX WITH OR CHANGE TO RAIN DURING THE DAY
MONDAY...AND EVEN IF IT DOES STAY AS SNOW...WILL HAVE TOUGH TIME
ACCUMULATING. THE ONE THING TO WATCH FRO WITH INVERTED TROUGHS IS
IF IT LOCKS INTO ONE AREA...AND SETS UP CONVERGENT ONSHORE FLOW
SIMILAR TO COASTAL FRONT...WHICH WOULD GIVE A SPECIFIC AREA
SEVERAL INCHES WITH VERY LITTLE ELSEWHERE. FOR NOW...HOLDING ONTO
THE IDEA OF A MOVING TROUGH WITH ACCUMS OF A COATING IN MOST
SPOTS. INLAND JUST LOOKS FOR MAINLY CLOUDY SKIES IN THIS TIME
FRAMEWITH A FEW FLURRIES.

MAY SEE A LITTLE BIT OF A BREAK ON TUE AS WEAK OFFSHORE SFC LOW
EXITS AND ALLOWS SOME RIDGING TO BUILD BACK IN FROM THE NE...THEN
WE START GETTING INTO THE EFFECTS OF THE IMPRESSIVE STORM SYSTEM
THAT RAPIDLY INTENSIFIES TO OUR WEST. PRECIP MOVES IN TUE
NIGHT...WHICH WILL BEGIN AS RAIN ALONG THE COAST...WITH EARLY LOWS
IN THE MID TO UPPER 30S. INLAND...PRECIP WILL START AS SNOW...AND
TRANSITIONS TO FREEZING RAIN OR RAIN LATE TUE NIGHT...AND
EVENTUALLY TRANSITION TO RAIN WED MORNING. THE HEAVY PRECIP WILL
MAINLY FALL AS RAIN WED AFTERNOON AND WED NIGHT. GFS QPF SEEMS
HIGH...AS IT MAY BE DEALING WITH CONVECTIVE SCALING ISSUES...AND
THE 1.5-2.5" OF THE EURO SEEMS MORE REASONABLE ATTM...STRONG SE
FLOW DEVELOPS EAST OF THE OCCLUSION POINT WHICH CROSSES WRN NEW
ENGLAND WED NIGHT. WILL SEE STRONG LOW LEVEL SE JET DEVELOP ABOVE
THE INVERSION AROUND THIS TIME AS WELL...AND ALTHOUGH THE
INVERSION SHOULD PREVENT FULL MIXING...ESPECIALLY OVER
LAND...COULD SEE WIND GUSTS APPROACHING ADV LEVELS. HIGHS WED WILL
LKLY OCCUR LATE IN THE DAY WED OR WED EVE...AND WILL MAKE A RUN AT
50 IN SRN NH AND ALONG THE COAST.

SHARP BACK EDGE TO THE RAIN WILL CROSS THE REGION EARLY WED AND
RAIN SHOULD END FROM SW TO NE DURING THE MORNING AND EARLY
AFTERNOON...WITH SOME PARTIAL CLEARING POSSIBLE IN THE AFTERNOON.
GUSTY W-SW WINDS WILL DEVELOP BEHIND THE SYSTEM....BUT HIGHS WILL
STILL BE ABV NORMAL...IN THE 40S.

&&

.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
SHORT TERM...MVFR CONDITIONS WILL CONTINUE UNTIL ABOUT DAYBREAK
IN THE CT RIVER VALLEY AS LOW LEVEL MOISTURE HAS BECOME TRAPPED.
SHOULD SEE ALL AREAS RETURN TO VFR DURING THE DAY AND THEN MORE
MOISTURE WILL WORK ITS WAY INTO THE REGION AS LOW LEVEL WIND FLOW
TURNS ON SHORE. THIS WILL BRING SOME MVFR CEILING AND POSSIBLE
SOME LIGHT SNOW SHOWERS FROM SATURDAY EVENING THROUGH MONDAY.


LONG TERM...POSSIBLE PERIODS OF MVFR TO IFR AT COASTAL TERMINALS
SUN NIGHT INTO MONDAY AS INVERTED TROUGH DEVELOPS ACROSS THE GULF
OF ME. MVFR LIKELY TO HOLD TUE INTO TUE NIGHT...WITH LOWERING TO
IFR LATE TUE NIGHT AND WED IN RAIN...WITH INCREASING E-SE WINDS
LATE IN THE DAY WED.

&&

.MARINE...
SHORT TERM...WINDS AND SEAS WILL REMAIN BELOW SCA CONDITIONS THRU
SUNDAY.

LONG TERM...WATER REMAIN BLO SCA LVLS SUN NIGHT THROUGH TUE
NIGHT. STRONG LOW PRES TO THE WEST WILL SEE WINDS INCREASE TO
GALES WED AFTERNOON WITH BORDERLINE STORM FORCE WINDS POSSIBLE WED
NIGHT.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.

&&

$$
KISTNER/CEMPA



000
FXUS61 KBOX 201204
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
704 AM EST SAT DEC 20 2014

.SYNOPSIS...
SCATTERED SNOW SHOWERS WILL GRADUALLY OVERSPREAD THE REGION FROM
EAST TO WEST LATER TODAY INTO SUNDAY.  THE EXCEPTION WILL BE THE
IMMEDIATE SOUTHEAST NEW ENGLAND COAST...WHERE IT SHOULD BECOME MILD
ENOUGH FOR SCATTERED RAIN SHOWERS. WEAK LOW PRESSURE WILL PASS SOUTH
OF NEW ENGLAND...BRINGING ANOTHER PERIOD OF PRECIPITATION. A MUCH
STRONGER STORM PASSING WEST OF NEW ENGLAND WILL BRING HEAVY
RAINFALL...GUSTY WINDS AND COASTAL FLOODING CONCERNS TO THE REGION
WEDNESDAY INTO WEDNESDAY EVENING. DRY BUT VERY WINDY CONDITIONS
FOLLOW FOR CHRISTMAS DAY INTO FRIDAY.

&&

.NEAR TERM /UNTIL NOON TODAY/...

700 AM UPDATE...

TREND IN THE FORECAST REMAINS ON TRACK. NORTHEASTERLY FLOW ONSHORE
HAS LEAD TO A FEW FLURRIES ACROSS THE CAPE AND PLYMOUTH COUNTY.
SHOULD BE LOCALIZED TO THIS REGION AS THE FLOW OVER BOSTON AND
TAUNTON ARE NORTHWEST. OTHERWISE CLOUDS ARE SLOWLY STARTING TO
FILL.

PREVIOUS DISCUSSION...

AN APPROACHING SHORTWAVE HAS ALLOWED WINDS JUST OFF THE GROUND TO
BECOME EASTERLY.  THIS WAS ALLOWING LOW CLOUDS TO BACK INTO
SOUTHEAST MA/RI EARLY THIS MORNING.  EXPECT THIS TREND TO CONTINUE
WITH LOW CLOUDS CONTINUING TO GRADUALLY WORK FURTHER WEST...BUT M.
SUNNY SKIES SHOULD PREVAIL THIS MORNING IN NORTHWEST MA.
MEANWHILE...SOME OCEAN EFFECT FLURRIES/LIGHT SNOW SHOWERS MAY
DEVELOP ACROSS PLYMOUTH COUNTY AND ONTO THE CAPE/ISLANDS THIS
MORNING.

&&

.SHORT TERM /NOON TODAY THROUGH 6 PM SUNDAY/...
THIS AFTERNOON AND TONIGHT...

INTERESTING MESOSCALE SETUP AS AN INVERTED TROUGH COMBINES WITH SOME
OCEAN ENHANCEMENT.  APPROACHING UPPER LEVEL SHORTWAVE WILL ALLOW FOR
EASTERLY FLOW JUST OFF THE GROUND.  THIS COMBINED WITH NORTHEAST
SURFACE WINDS WILL ALLOW LOW LEVEL OF THE ATMOSPHERE TO MOISTEN.
SOUNDINGS ACROSS EASTERN NEW ENGLAND BECOME SATURATED ALL THE WAY UP
TO THE -9C LAYER JUST ABOVE 850 MB.  THIS IS FAVORABLE FOR SOME
DECENT SNOWGROWTH...ITS JUST LOWER IN THE ATMOSPHERE THAN WE
TYPICALLY SEE WITH MORE SYNOPTIC SNOW EVENTS.  WHILE THIS IS NOT A
TRUE OCEAN EFFECT EVENT...DELTA T VALUES FROM THE MIXED LAYER TO THE
OCEAN ARE AROUND 15C.  THEREFORE...EXPECT SOME OCEAN ENHANCEMENT.

TIMING:

WHILE FLURRIES/LIGHT SNOW SHOWERS MAY OCCUR ACROSS FAR SOUTHEAST NEW
ENGLAND THIS MORNING.  THE MORE SUBSTANTIAL  PRECIPITATION SHOULD
OVERSPREAD PLYMOUTH COUNTY AS WELL AS THE CAPE AND ISLANDS THIS
AFTERNOON.  GIVEN EASTERLY FLOW JUST OFF THE GROUND...EXPECT SNOW
SHOWERS TO OVERSPREAD MOST OF EASTERN NEW ENGLAND THIS EVENING AS
LOW LEVELS MOISTEN.  IN FACT...SHOULD SEE AT LEAST SOME SCATTERED
SNOW SHOWERS AFFECT EVEN OUR FAR WESTERN ZONES.

PTYPE:

MAINLY SNOW FOR ALL BUT PORTIONS OF COASTAL PLYMOUTH COUNTY AND ONTO
THE CAPE/ISLANDS.  A SUBTLE COASTAL FRONT LOOKS TO SETUP ACROSS
SOUTHEAST COASTAL PLYMOUTH COUNTY.  PTYPE WILL BE SNOW TO THE
NORTHWEST OF THIS REGION...BUT ENOUGH MILD AIR SHOULD COME IN OFF
THE OCEAN FOR A CHANGE TO RAIN SHOWERS SOUTHEAST OF THIS REGION.
NOT EXPECTING THE POSITION OF THIS SUBTLE BOUNDARY TO CHANGE MUCH
THROUGH SUNDAY MORNING.

SNOW ACCUMULATIONS:

WE ARE GENERALLY LOOKING AT A COATING TO 2 INCHES OF SNOW ACROSS
MOST OF THE REGION.  THE MAIN FOCUS FOR 1 TO 2 INCHES WILL BE ACROSS
PORTIONS OF SOUTHEAST MA...AWAY FROM THE SOUTHEAST PLYMOUTH COUNTY
COAST.  ALSO...THE WORCESTER HILLS INTO NORTHWEST RHODE ISLAND MIGHT
BE ANOTHER AREA AS A RESULT OF THE SUBTLE UPSLOPE COMPONENT TO THE
WIND.  YOU CAN ACTUALLY SEE THAT IN SOME OF THE HIGH RESOLUTION
MODEL GUIDANCE.

THERE IS ONE AREA TO WATCH IN PARTICULAR...FROM NORTHWEST PLYMOUTH
COUNTY AND INTO NORFOLK COUNTY BASED ON MESOSCALE MODELS AND PATTERN
RECOGNITION.  WOULD NOT BE SURPRISED TO SEE VERY LOCALIZED 3 TO 4
INCH SNOW AMOUNTS...GIVEN SOME OCEAN ENHANCEMENT AND A LITTLE FOCUS
ON THE COASTAL FRONT.  WILL TRY TO HIGHLIGHT THIS AREA IN OUR
SNOWFALL AND PROBABILISTIC  GRAPHICS.

SUNDAY...

SCATTERED SNOW SHOWERS WILL CONTINUE DURING THE MORNING WITH MOIST
EASTERLY FLOW IN THE LOW LEVELS. AGAIN...PTYPE WILL BE SNOW EXCEPT
ACROSS SOUTHEAST PLYMOUTH COUNTY/CAPE AND ISLANDS WHERE BOUNDARY
LAYER WILL PROBABLY BE WARM ENOUGH FOR RAIN SHOWERS.  WHILE SOME
LIGHT PRECIPITATION MAY LINGER INTO SUNDAY AFTERNOON...EXPECT A
DECREASE IN AREAL COVERAGE THROUGH THE AFTERNOON AS LOW LEVEL LIFT
WEAKENS.  IT WILL REMAIN CLOUDY THOUGH WITH TEMPS IN THE 30S.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
HIGHLIGHTS...

* INVERTED TROUGH WILL BRING RAIN/SNOW SHOWERS TO THE MASS EAST
  COASTLINE MONDAY INTO TUES MORNING.
* WEAK WAVE OF LOW PRESSURE MON NIGHT/TUESDAY COULD BRING WINTRY
  MIX TO INTERIOR
* ANOMALOUS SYSTEM ACROSS THE GREAT LAKES WILL BRING HEAVY
  RAIN...GUSTY WINDS AND COASTAL FLOODING CONCERNS AROUND CHRISTMAS
  EVE

OVERVIEW...

OVERALL 00Z GUIDANCE IS IN AGREEMENT SYNOPTICALLY WITH ISSUES ON
TIMING AND SMALLER SCALE FEATURES. IT REMAINS EVIDENT THAT AN
AMPLIFIED MID-UPPER LEVEL TROUGH AND PCPN FOCUSING LEAD SURFACE
LOW/FRONTAL SYSTEM WILL STEADILY PROGRESS TO THE EAST-CENTRAL U.S.
TUE AS EMBEDDED IMPULSES DIG TO THE LEE OF AN AMPLIFIED ERN
PACIFIC/WEST COAST RIDGE ALOFT. THE SUPPORTING AND INCREASINGLY
NEGATIVE-TILT TROUGH ALOFT WORKS OVER THE ERN US AND OUT THROUGH THE
NERN STATES INTO DAYS 4/5 WED/THU.  MODELS/ENSEMBLES HAVE BEEN
FAIRLY CONSISTENT ON THIS AMPLIFIED PATTERN AND THE MOST RECENT
GEFS/ECMWF ENSEMBLE GUIDANCE SHOW GOOD CORRELATION TO NEXT THURSDAY.

HIGH PRESSURE AND UPPER LEVEL RIDGE OVER THE REGION WILL BEGIN TO
EXIT BY MONDAY. AT THE SURFACE APPEARS ANOTHER INVERTED
TROUGH/ONSHORE FLOW WILL YIELD TO PRECIP ALONG THE MASS COASTLINE ON
MONDAY. ASIDE FROM THIS QUICK MESOSCALE EVENT THE MAIN FOCUS IS ON
THE LONGWAVE DIGGING TROUGH OVER THE CENTRAL CONUS WHICH WILL PUSH A
FEW SHORTWAVES THROUGH THE FLOW. FIRST ONE DEVELOPS A WEAK WAVE
MOVING TOWARDS THE REGION LATE MONDAY INTO TUESDAY. THERE IS STILL
SOME UNCERTAINTY WITH THE LOCATION/STRENGTH OF THIS SYSTEM BUT
APPEARS THAT THERE IS THE POSSIBILITY OF A SNOW/WINTRY MIX IN THE
INTERIOR. AS THIS SYSTEM DEPARTS AN ANOMALOUS LOW OVER THE GREAT
LAKES WILL DEVELOP A SECONDARY LOW JUST WEST OF SOUTHERN NEW ENGLAND
     PER ENSEMBLE GUIDANCE. STILL A SOME SPREAD BUT IF THIS DOUBLE LOW
DOES DEVELOP THEN THE RAIN AND WIND ASPECT OF THE SYSTEM
INCREASES...DETAILS BELOW. STILL NEED TO WORK OUT MINOR DETAILS WITH
THIS PARTICULAR SYSTEM BUT WITH 3 TO 4 STANDARD DEVIATIONS AWAY AND
GENERAL MODEL AGREEMENT HAVE HIGH CONFIDENCE THIS SYSTEM WILL IMPACT
SOUTHERN NEW ENGLAND.

DETAILS...

SUNDAY NIGHT INTO TUESDAY...MODERATE CONFIDENCE.

HIGH PRESSURE AND UPPER LEVEL RIDGE WILL BEGIN TO MOVE OFFSHORE AS
DIGGING TROUGH BEGINS TO SET-UP OVER THE CENTRAL CONUS. APPEARS
ANOTHER MESO-SCALE INVERTED TROUGH WILL SET UP ON MONDAY AND LAST
INTO EARLY TUESDAY MORNING. GUIDANCE SHOWS THAT RAIN/SNOW SHOWERS
WILL DEVELOP ALONG THE MASS EAST COASTLINE THANKS TO ONSHORE
EASTERLY FLOW. APPEARS THE COLUMN WILL SATURATE PER BUFKIT SOUNDINGS
AND SOUTHERLY FLOW ALOFT. BOTH THE NAM AND GFS SHOW QPF MAKING IT
ONSHORE DURING THIS TIME FRAME. HOWEVER THE EC IS SLIGHTLY SLOWER
AND KEEP THE BULK OF THE PRECIP JUST OFFSHORE. ADD A CHANCE OF POPS
DUE TO THE NAM/GFS MODEL CONTINUITY.

BY LATE MONDAY NIGHT INTO TUESDAY A SOUTHERN BRANCH STORM SYSTEM
FORMS ALONG THE SE COAST AND TAKES A TRACK OFF THE MID ATLANTIC
COAST. THIS SYSTEM GETS CAUGHT UP WITH THE OVERALL LARGE SCALE
AMPLIFICATION OF THE UPPER AIR PATTERN. THERE IS DECENT WARM
ADVECTION WITH COLD AIR DAMMING ACROSS THE INTERIOR. BIGGEST
QUESTION WILL BE IS THERE ENOUGH MOISTURE FOR PRECIP DURING THIS
TIME FRAME. IF PRECIP OVERRUNS THEN COULD SEE FREEZING RAIN/DRIZZLE
ACROSS THE INTERIOR LATE MONDAY INTO TUESDAY MORNING. DURING THE DAY
ON TUESDAY...GOOD AMOUNT OF WARM AIR WILL PUSH SURFACE TEMPS ABOVE
FREEZING ALLOWING FOR ANY PRECIP TO BE MORE OF THE LIQUID VARIETY
AHEAD OF THE CHRISTMAS EVE STORM. HOWEVER GUIDANCE IS ALWAYS TOO
FAST IN SCOURING TEMPS OUT ESP ACROSS THE CT VALLEY SO WE WILL NEED
TO MONITOR THIS CLOSELY...ESP DUE TO LIGHT WINDS AND THE HIGH IN
EASTERN CANADA.

WE COULD ALSO SEE SOME MINOR COASTAL FLOODING CONCERNS ON TUESDAY. SEE
BELOW FOR MORE DETAILS.

WEDNESDAY INTO THURSDAY...HIGH CONFIDENCE IN SYSTEM LOW CONFIDENCE
ON DETAILS.

STRONG ANOMALOUS SYSTEM WILL STRENGTHEN OVER THE GREAT
LAKES...DEVELOPING A POTENTIAL SECONDARY SURFACE LOW JUST WEST OF
SOUTHERN NEW ENGLAND. STILL A LOT OF DETAILS TO WORK OUT AS THIS
SYSTEM IS STILL 5 DAYS AWAY...HOWEVER ENSEMBLES CONTINUE TO SHOW
STRONG AGREEMENT SO HAVE INCREASING CONFIDENCE THAT A POTENT STORM
WILL OCCUR. LATEST 00Z GUIDANCE SHOWS THAT MOST PRECIP WILL BE
LIQUID WITH A DEEP SUBTROPICAL CONNECTION BACK ACROSS THE GULF OF
MEXICO...PW ANOMALIES FORECAST TO RISE BETWEEN +3 TO +4. CURRENT
PWATS ARE PROGGED ABOVE 1.6 INCHES SO HAVE CONTINUED THE CATEGORICAL
POPS. TEMPERATURES WILL BE WELL ABOVE AVERAGE...IN FACT WE MAY BE
CLOSE AT BREAKING RECORD HIGH TEMPS IF TEMPS WARM TO 60F OR ABOVE ON
CHRISTMAS EVE.  AS THE SYSTEM WRAPS UP INTO CANADA...COLD AIR
ADVECTION SHOULD CIRCULATE AROUND AND BEGIN A TRANSITION FROM
SOUTHWEST TO NORTHEAST IN TURNING P-TYPE TO SNOW. HOWEVER LATEST
GUIDANCE DOES SHOW A QUICK MOVING DRY SLOT SO SNOWFALL WILL STRUGGLE
DUE TO LACK OF MOISTURE.

THIS SYSTEM IS QUITE POTENT SO WE WILL NEED TO WATCH FOR POTENTIAL
HAZARDS. CURRENTLY THINK THAT WE COULD POSSIBLE URBAN FLOODING
ISSUES AS MODELS PROGGED WELL OVER 1.5 INCHES OF QPF. LATEST EC EVEN
SHOWS 2.5 INCHES OF QPF IS POSSIBLE. THE GEFS SHOW A MOISTURE FLUX
AT 850 MB BEING 4 TO 5 STANDARD DEVIATIONS AWAY...AND WITH THE
TROPICAL CONNECTION AND STRONG SOUTHERLY FLOW COULD SEE HIGHER
AMOUNTS DUE TO TOPOGRAPHY ENHANCEMENTS. RAIN FALL RECORDS MAY FALL
IF EVERYTHING FALLS INTO PLACE.

ALSO BELIEVE THAT WE MAY SEE SOME WIND ISSUES WITH THIS SYSTEM.
GUIDANCE RIGHT NOW IS SHOWING A 45 TO 55 KT JET AT 925 MB...HOWEVER
IT WILL BE HARD TO BREAK THE INVERSION WITH THE SOUTHERLY FLOW.
RIGHT NOW BELIEVE THAT WIND ADVISORIES MAY BE NEEDED BUT IF THIS
SYSTEM STRENGTHEN EVEN MORE SO A STRONGER JET IS POSSIBLE.

CONTINUED THE MENTIONED OF ISOLATED THUNDER IN THE FORECAST PER PREV
FORECASTER SUGGESTION. BELIEVE IT COULD BE POSSIBLE AS SOUTHERN NEW
ENGLAND WILL BE IN THE WARM SECTOR...WITH THE ANOMALOUS JET AND
SHOWALTERS CLOSE TO ZERO.

FRIDAY...LOW CONFIDENCE.

ONCE UPPER LEVEL LOW MOVES INTO SOUTHERN CANADA...EXPECT A RATHER
FAST UPPER W FLOW IN PLACE. MAY SEE LEFTOVER SNOW SHOWERS BUT TEMPS
WILL FALL BACK CLOSE TO SEASONAL NORMS.

&&

.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH SUNDAY/...

700 AM UPDATE...

TODAY...MODERATE CONFIDENCE.  MVFR CIGS WILL CONTINUE TO OVERSPREAD
EASTERN NEW ENGLAND THIS MORNING AND EVENTUALLY INTO THE INTERIOR
THIS AFTERNOON.  SCATTERED PRECIPITATION WILL OVERSPREAD
SOUTHEAST MA/CAPE/ISLANDS THIS AFTERNOON.  PTYPE MAINLY SNOW SHOWERS
NORTHWEST OF THE SOUTHEAST PLYMOUTH COUNTY COAST AND RAIN SHOWERS
SOUTHEAST OF THAT REGION. LOCALIZED IFR CONDITIONS POSSIBLE JUST
INLAND FROM THE SOUTHEAST NEW ENGLAND COAST...WHERE PTYPE IS SNOW.

TONIGHT AND SUNDAY...MODERATE CONFIDENCE.  MVFR CONDITIONS DOMINATE
IN LOWER CLOUDS AND SCATTERED PRECIPITATION.  LOCALIZED IFR
CONDITIONS POSSIBLE WITH THE BEST CHANCE IN SNOW SHOWERS.
PRECIPITATION AFFECTS MAINLY EASTERN NEW ENGLAND BUT STILL SOME
SCATTERED ACTIVITY ACROSS WESTERN NEW ENGLAND. PTYPE MAINLY SNOW
SHOWERS NORTHWEST OF THE SOUTHEAST PLYMOUTH COUNTY COAST...WITH RAIN
SHOWERS SOUTHEAST OF THAT REGION.

KBOS TERMINAL...MODERATE CONFIDENCE IN TAF.  SNOW SHOWERS MAY ARRIVE
TOWARDS 00Z THIS EVENING.

KBDL TERMINAL...MODERATE CONFIDENCE IN TAF.

OUTLOOK...SUNDAY NIGHT THROUGH WEDNESDAY...

MONDAY INTO TUESDAY...MODERATE CONFIDENCE. EXPECT MOSTLY
VFR...ISOLATED MVFR ALONG THE MASS EAST COASTLINE IN RAIN/SNOW
SHOWERS.

TUESDAY NIGHT INTO WEDNESDAY...MODERATE CONFIDENCE. CONDITIONS WILL
BE DETERIORATING AS HEAVY DOWNPOURS...ISO THUNDER AND GUSTY SOUTHERLY
WINDS MOVE INTO THE REGION BY WEDNESDAY. COULD SEE MVFR TO IFR
CONDITIONS IN CIGS AND VSBYS.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /TODAY THROUGH SUNDAY/...HIGH CONFIDENCE.

HIGH PRESSURE ACROSS QUEBEC WILL RESULT IN PERSISTENT NORTHEAST
WINDS ACROSS THE WATERS THROUGH THE WEEKEND.  WIND GUSTS UP TO 20
KNOTS WITH SEAS BETWEEN 2 AND 4 FEET ARE EXPECTED FOR MOST
WATERS...SO NO HEADLINES PLANNED. THERE IS A LOW PROBABILITY THAT A
BRIEF SURGE OF NORTHEAST WIND GUSTS NEAR 25 KNOTS WITH MARGINAL 5
FOOT SEAS COULD AFFECT OUR NORTHERN WATERS LATE TONIGHT INTO SUN
MORNING...BUT NOT CONFIDENT ENOUGH TO ISSUE ANY HEADLINES AT THIS
POINT.

OUTLOOK...SUNDAY NIGHT INTO WEDNESDAY...MODERATE TO HIGH
CONFIDENCE.

SUNDAY INTO MONDAY. CONTINUOUS NORTHEAST FLOW WILL KEEP SEAS CHOPPY.
LINGERING NORTHEAST SWELL MAY BUMP SEAS ABOVE 5FT ESP ACROSS THE
NORTHEASTERN WATERS. SCA MAY BE NEEDED...BUT LOWER CONFIDENCE.

TUESDAY INTO WEDNESDAY...NE WINDS WILL INCREASE...GUSTING TO 30 KT
TUE THEN SHIFT TO SE GUSTING TO 30-35 KT WED...HIGHEST ON THE OUTER
WATERS. SEAS BUILD UP TO 7-11 FT BY WED. GALES WILL BE NEEDED.

&&

.TIDES/COASTAL FLOODING...
HIGH ASTRONOMICAL TIDES WILL OCCUR TUESDAY THROUGH THURSDAY. BREAKING
IT DOWN...ON TUESDAY HIGH TIDE AT BOSTON WILL BE 11.6 FT. THERE WILL
BE ONSHORE FLOW DURING THIS HIGH TIDE ALLOWING FOR MINOR SPLASHOVER.
IF WIND GUSTS INCREASE THEN COULD POSSIBLE SEE MINOR COASTAL
FLOODING.

ON WEDNESDAY...WINDS WILL SWITCH TO A MORE SOUTHEASTERLY FLOW DURING
THE DAY AND INCREASE QUICKLY FROM APPROACHING SYSTEM AND DESCENT
PRESSURE FALLS. WEDNESDAY AFTERNOON HIGH TIDE IN BOSTON IS 11.7 FT
AND WITH ANY STRENGTH ON THE EASTERLY WIND FLOW WILL PUSH THE TIDE
OVER. RIGHT NOW BELIEVE MINOR COASTAL FLOODING IS POSSIBLE ALONG THE
EAST COASTLINE. HOWEVER WEDNESDAY EVENING...THE WIND GOES IN A MORE
SOUTHERLY DIRECTION AND HIGH TIDE IN PROVIDENCE WILL BE 5.2 FT. 925
MB LLJ STRENGTHENS TO 50-60 KTS WHICH COULD PUSH A DESCENT SURGE UP
ALONG THE SOUTH COAST DURING THE TIME OF HIGH TIDE. THINKING THAT
MINOR COASTAL FLOODING COULD OCCUR BUT CANNOT RULE OUT MODERATE
ALONG THE SOUTH COAST...ESP IF LLJ STRENGTHENS EVEN MORE.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...FRANK/DUNTEN
NEAR TERM...FRANK/DUNTEN
SHORT TERM...FRANK
LONG TERM...DUNTEN
AVIATION...FRANK/DUNTEN
MARINE...FRANK/DUNTEN
TIDES/COASTAL FLOODING...



000
FXUS61 KBOX 201204
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
704 AM EST SAT DEC 20 2014

.SYNOPSIS...
SCATTERED SNOW SHOWERS WILL GRADUALLY OVERSPREAD THE REGION FROM
EAST TO WEST LATER TODAY INTO SUNDAY.  THE EXCEPTION WILL BE THE
IMMEDIATE SOUTHEAST NEW ENGLAND COAST...WHERE IT SHOULD BECOME MILD
ENOUGH FOR SCATTERED RAIN SHOWERS. WEAK LOW PRESSURE WILL PASS SOUTH
OF NEW ENGLAND...BRINGING ANOTHER PERIOD OF PRECIPITATION. A MUCH
STRONGER STORM PASSING WEST OF NEW ENGLAND WILL BRING HEAVY
RAINFALL...GUSTY WINDS AND COASTAL FLOODING CONCERNS TO THE REGION
WEDNESDAY INTO WEDNESDAY EVENING. DRY BUT VERY WINDY CONDITIONS
FOLLOW FOR CHRISTMAS DAY INTO FRIDAY.

&&

.NEAR TERM /UNTIL NOON TODAY/...

700 AM UPDATE...

TREND IN THE FORECAST REMAINS ON TRACK. NORTHEASTERLY FLOW ONSHORE
HAS LEAD TO A FEW FLURRIES ACROSS THE CAPE AND PLYMOUTH COUNTY.
SHOULD BE LOCALIZED TO THIS REGION AS THE FLOW OVER BOSTON AND
TAUNTON ARE NORTHWEST. OTHERWISE CLOUDS ARE SLOWLY STARTING TO
FILL.

PREVIOUS DISCUSSION...

AN APPROACHING SHORTWAVE HAS ALLOWED WINDS JUST OFF THE GROUND TO
BECOME EASTERLY.  THIS WAS ALLOWING LOW CLOUDS TO BACK INTO
SOUTHEAST MA/RI EARLY THIS MORNING.  EXPECT THIS TREND TO CONTINUE
WITH LOW CLOUDS CONTINUING TO GRADUALLY WORK FURTHER WEST...BUT M.
SUNNY SKIES SHOULD PREVAIL THIS MORNING IN NORTHWEST MA.
MEANWHILE...SOME OCEAN EFFECT FLURRIES/LIGHT SNOW SHOWERS MAY
DEVELOP ACROSS PLYMOUTH COUNTY AND ONTO THE CAPE/ISLANDS THIS
MORNING.

&&

.SHORT TERM /NOON TODAY THROUGH 6 PM SUNDAY/...
THIS AFTERNOON AND TONIGHT...

INTERESTING MESOSCALE SETUP AS AN INVERTED TROUGH COMBINES WITH SOME
OCEAN ENHANCEMENT.  APPROACHING UPPER LEVEL SHORTWAVE WILL ALLOW FOR
EASTERLY FLOW JUST OFF THE GROUND.  THIS COMBINED WITH NORTHEAST
SURFACE WINDS WILL ALLOW LOW LEVEL OF THE ATMOSPHERE TO MOISTEN.
SOUNDINGS ACROSS EASTERN NEW ENGLAND BECOME SATURATED ALL THE WAY UP
TO THE -9C LAYER JUST ABOVE 850 MB.  THIS IS FAVORABLE FOR SOME
DECENT SNOWGROWTH...ITS JUST LOWER IN THE ATMOSPHERE THAN WE
TYPICALLY SEE WITH MORE SYNOPTIC SNOW EVENTS.  WHILE THIS IS NOT A
TRUE OCEAN EFFECT EVENT...DELTA T VALUES FROM THE MIXED LAYER TO THE
OCEAN ARE AROUND 15C.  THEREFORE...EXPECT SOME OCEAN ENHANCEMENT.

TIMING:

WHILE FLURRIES/LIGHT SNOW SHOWERS MAY OCCUR ACROSS FAR SOUTHEAST NEW
ENGLAND THIS MORNING.  THE MORE SUBSTANTIAL  PRECIPITATION SHOULD
OVERSPREAD PLYMOUTH COUNTY AS WELL AS THE CAPE AND ISLANDS THIS
AFTERNOON.  GIVEN EASTERLY FLOW JUST OFF THE GROUND...EXPECT SNOW
SHOWERS TO OVERSPREAD MOST OF EASTERN NEW ENGLAND THIS EVENING AS
LOW LEVELS MOISTEN.  IN FACT...SHOULD SEE AT LEAST SOME SCATTERED
SNOW SHOWERS AFFECT EVEN OUR FAR WESTERN ZONES.

PTYPE:

MAINLY SNOW FOR ALL BUT PORTIONS OF COASTAL PLYMOUTH COUNTY AND ONTO
THE CAPE/ISLANDS.  A SUBTLE COASTAL FRONT LOOKS TO SETUP ACROSS
SOUTHEAST COASTAL PLYMOUTH COUNTY.  PTYPE WILL BE SNOW TO THE
NORTHWEST OF THIS REGION...BUT ENOUGH MILD AIR SHOULD COME IN OFF
THE OCEAN FOR A CHANGE TO RAIN SHOWERS SOUTHEAST OF THIS REGION.
NOT EXPECTING THE POSITION OF THIS SUBTLE BOUNDARY TO CHANGE MUCH
THROUGH SUNDAY MORNING.

SNOW ACCUMULATIONS:

WE ARE GENERALLY LOOKING AT A COATING TO 2 INCHES OF SNOW ACROSS
MOST OF THE REGION.  THE MAIN FOCUS FOR 1 TO 2 INCHES WILL BE ACROSS
PORTIONS OF SOUTHEAST MA...AWAY FROM THE SOUTHEAST PLYMOUTH COUNTY
COAST.  ALSO...THE WORCESTER HILLS INTO NORTHWEST RHODE ISLAND MIGHT
BE ANOTHER AREA AS A RESULT OF THE SUBTLE UPSLOPE COMPONENT TO THE
WIND.  YOU CAN ACTUALLY SEE THAT IN SOME OF THE HIGH RESOLUTION
MODEL GUIDANCE.

THERE IS ONE AREA TO WATCH IN PARTICULAR...FROM NORTHWEST PLYMOUTH
COUNTY AND INTO NORFOLK COUNTY BASED ON MESOSCALE MODELS AND PATTERN
RECOGNITION.  WOULD NOT BE SURPRISED TO SEE VERY LOCALIZED 3 TO 4
INCH SNOW AMOUNTS...GIVEN SOME OCEAN ENHANCEMENT AND A LITTLE FOCUS
ON THE COASTAL FRONT.  WILL TRY TO HIGHLIGHT THIS AREA IN OUR
SNOWFALL AND PROBABILISTIC  GRAPHICS.

SUNDAY...

SCATTERED SNOW SHOWERS WILL CONTINUE DURING THE MORNING WITH MOIST
EASTERLY FLOW IN THE LOW LEVELS. AGAIN...PTYPE WILL BE SNOW EXCEPT
ACROSS SOUTHEAST PLYMOUTH COUNTY/CAPE AND ISLANDS WHERE BOUNDARY
LAYER WILL PROBABLY BE WARM ENOUGH FOR RAIN SHOWERS.  WHILE SOME
LIGHT PRECIPITATION MAY LINGER INTO SUNDAY AFTERNOON...EXPECT A
DECREASE IN AREAL COVERAGE THROUGH THE AFTERNOON AS LOW LEVEL LIFT
WEAKENS.  IT WILL REMAIN CLOUDY THOUGH WITH TEMPS IN THE 30S.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
HIGHLIGHTS...

* INVERTED TROUGH WILL BRING RAIN/SNOW SHOWERS TO THE MASS EAST
  COASTLINE MONDAY INTO TUES MORNING.
* WEAK WAVE OF LOW PRESSURE MON NIGHT/TUESDAY COULD BRING WINTRY
  MIX TO INTERIOR
* ANOMALOUS SYSTEM ACROSS THE GREAT LAKES WILL BRING HEAVY
  RAIN...GUSTY WINDS AND COASTAL FLOODING CONCERNS AROUND CHRISTMAS
  EVE

OVERVIEW...

OVERALL 00Z GUIDANCE IS IN AGREEMENT SYNOPTICALLY WITH ISSUES ON
TIMING AND SMALLER SCALE FEATURES. IT REMAINS EVIDENT THAT AN
AMPLIFIED MID-UPPER LEVEL TROUGH AND PCPN FOCUSING LEAD SURFACE
LOW/FRONTAL SYSTEM WILL STEADILY PROGRESS TO THE EAST-CENTRAL U.S.
TUE AS EMBEDDED IMPULSES DIG TO THE LEE OF AN AMPLIFIED ERN
PACIFIC/WEST COAST RIDGE ALOFT. THE SUPPORTING AND INCREASINGLY
NEGATIVE-TILT TROUGH ALOFT WORKS OVER THE ERN US AND OUT THROUGH THE
NERN STATES INTO DAYS 4/5 WED/THU.  MODELS/ENSEMBLES HAVE BEEN
FAIRLY CONSISTENT ON THIS AMPLIFIED PATTERN AND THE MOST RECENT
GEFS/ECMWF ENSEMBLE GUIDANCE SHOW GOOD CORRELATION TO NEXT THURSDAY.

HIGH PRESSURE AND UPPER LEVEL RIDGE OVER THE REGION WILL BEGIN TO
EXIT BY MONDAY. AT THE SURFACE APPEARS ANOTHER INVERTED
TROUGH/ONSHORE FLOW WILL YIELD TO PRECIP ALONG THE MASS COASTLINE ON
MONDAY. ASIDE FROM THIS QUICK MESOSCALE EVENT THE MAIN FOCUS IS ON
THE LONGWAVE DIGGING TROUGH OVER THE CENTRAL CONUS WHICH WILL PUSH A
FEW SHORTWAVES THROUGH THE FLOW. FIRST ONE DEVELOPS A WEAK WAVE
MOVING TOWARDS THE REGION LATE MONDAY INTO TUESDAY. THERE IS STILL
SOME UNCERTAINTY WITH THE LOCATION/STRENGTH OF THIS SYSTEM BUT
APPEARS THAT THERE IS THE POSSIBILITY OF A SNOW/WINTRY MIX IN THE
INTERIOR. AS THIS SYSTEM DEPARTS AN ANOMALOUS LOW OVER THE GREAT
LAKES WILL DEVELOP A SECONDARY LOW JUST WEST OF SOUTHERN NEW ENGLAND
     PER ENSEMBLE GUIDANCE. STILL A SOME SPREAD BUT IF THIS DOUBLE LOW
DOES DEVELOP THEN THE RAIN AND WIND ASPECT OF THE SYSTEM
INCREASES...DETAILS BELOW. STILL NEED TO WORK OUT MINOR DETAILS WITH
THIS PARTICULAR SYSTEM BUT WITH 3 TO 4 STANDARD DEVIATIONS AWAY AND
GENERAL MODEL AGREEMENT HAVE HIGH CONFIDENCE THIS SYSTEM WILL IMPACT
SOUTHERN NEW ENGLAND.

DETAILS...

SUNDAY NIGHT INTO TUESDAY...MODERATE CONFIDENCE.

HIGH PRESSURE AND UPPER LEVEL RIDGE WILL BEGIN TO MOVE OFFSHORE AS
DIGGING TROUGH BEGINS TO SET-UP OVER THE CENTRAL CONUS. APPEARS
ANOTHER MESO-SCALE INVERTED TROUGH WILL SET UP ON MONDAY AND LAST
INTO EARLY TUESDAY MORNING. GUIDANCE SHOWS THAT RAIN/SNOW SHOWERS
WILL DEVELOP ALONG THE MASS EAST COASTLINE THANKS TO ONSHORE
EASTERLY FLOW. APPEARS THE COLUMN WILL SATURATE PER BUFKIT SOUNDINGS
AND SOUTHERLY FLOW ALOFT. BOTH THE NAM AND GFS SHOW QPF MAKING IT
ONSHORE DURING THIS TIME FRAME. HOWEVER THE EC IS SLIGHTLY SLOWER
AND KEEP THE BULK OF THE PRECIP JUST OFFSHORE. ADD A CHANCE OF POPS
DUE TO THE NAM/GFS MODEL CONTINUITY.

BY LATE MONDAY NIGHT INTO TUESDAY A SOUTHERN BRANCH STORM SYSTEM
FORMS ALONG THE SE COAST AND TAKES A TRACK OFF THE MID ATLANTIC
COAST. THIS SYSTEM GETS CAUGHT UP WITH THE OVERALL LARGE SCALE
AMPLIFICATION OF THE UPPER AIR PATTERN. THERE IS DECENT WARM
ADVECTION WITH COLD AIR DAMMING ACROSS THE INTERIOR. BIGGEST
QUESTION WILL BE IS THERE ENOUGH MOISTURE FOR PRECIP DURING THIS
TIME FRAME. IF PRECIP OVERRUNS THEN COULD SEE FREEZING RAIN/DRIZZLE
ACROSS THE INTERIOR LATE MONDAY INTO TUESDAY MORNING. DURING THE DAY
ON TUESDAY...GOOD AMOUNT OF WARM AIR WILL PUSH SURFACE TEMPS ABOVE
FREEZING ALLOWING FOR ANY PRECIP TO BE MORE OF THE LIQUID VARIETY
AHEAD OF THE CHRISTMAS EVE STORM. HOWEVER GUIDANCE IS ALWAYS TOO
FAST IN SCOURING TEMPS OUT ESP ACROSS THE CT VALLEY SO WE WILL NEED
TO MONITOR THIS CLOSELY...ESP DUE TO LIGHT WINDS AND THE HIGH IN
EASTERN CANADA.

WE COULD ALSO SEE SOME MINOR COASTAL FLOODING CONCERNS ON TUESDAY. SEE
BELOW FOR MORE DETAILS.

WEDNESDAY INTO THURSDAY...HIGH CONFIDENCE IN SYSTEM LOW CONFIDENCE
ON DETAILS.

STRONG ANOMALOUS SYSTEM WILL STRENGTHEN OVER THE GREAT
LAKES...DEVELOPING A POTENTIAL SECONDARY SURFACE LOW JUST WEST OF
SOUTHERN NEW ENGLAND. STILL A LOT OF DETAILS TO WORK OUT AS THIS
SYSTEM IS STILL 5 DAYS AWAY...HOWEVER ENSEMBLES CONTINUE TO SHOW
STRONG AGREEMENT SO HAVE INCREASING CONFIDENCE THAT A POTENT STORM
WILL OCCUR. LATEST 00Z GUIDANCE SHOWS THAT MOST PRECIP WILL BE
LIQUID WITH A DEEP SUBTROPICAL CONNECTION BACK ACROSS THE GULF OF
MEXICO...PW ANOMALIES FORECAST TO RISE BETWEEN +3 TO +4. CURRENT
PWATS ARE PROGGED ABOVE 1.6 INCHES SO HAVE CONTINUED THE CATEGORICAL
POPS. TEMPERATURES WILL BE WELL ABOVE AVERAGE...IN FACT WE MAY BE
CLOSE AT BREAKING RECORD HIGH TEMPS IF TEMPS WARM TO 60F OR ABOVE ON
CHRISTMAS EVE.  AS THE SYSTEM WRAPS UP INTO CANADA...COLD AIR
ADVECTION SHOULD CIRCULATE AROUND AND BEGIN A TRANSITION FROM
SOUTHWEST TO NORTHEAST IN TURNING P-TYPE TO SNOW. HOWEVER LATEST
GUIDANCE DOES SHOW A QUICK MOVING DRY SLOT SO SNOWFALL WILL STRUGGLE
DUE TO LACK OF MOISTURE.

THIS SYSTEM IS QUITE POTENT SO WE WILL NEED TO WATCH FOR POTENTIAL
HAZARDS. CURRENTLY THINK THAT WE COULD POSSIBLE URBAN FLOODING
ISSUES AS MODELS PROGGED WELL OVER 1.5 INCHES OF QPF. LATEST EC EVEN
SHOWS 2.5 INCHES OF QPF IS POSSIBLE. THE GEFS SHOW A MOISTURE FLUX
AT 850 MB BEING 4 TO 5 STANDARD DEVIATIONS AWAY...AND WITH THE
TROPICAL CONNECTION AND STRONG SOUTHERLY FLOW COULD SEE HIGHER
AMOUNTS DUE TO TOPOGRAPHY ENHANCEMENTS. RAIN FALL RECORDS MAY FALL
IF EVERYTHING FALLS INTO PLACE.

ALSO BELIEVE THAT WE MAY SEE SOME WIND ISSUES WITH THIS SYSTEM.
GUIDANCE RIGHT NOW IS SHOWING A 45 TO 55 KT JET AT 925 MB...HOWEVER
IT WILL BE HARD TO BREAK THE INVERSION WITH THE SOUTHERLY FLOW.
RIGHT NOW BELIEVE THAT WIND ADVISORIES MAY BE NEEDED BUT IF THIS
SYSTEM STRENGTHEN EVEN MORE SO A STRONGER JET IS POSSIBLE.

CONTINUED THE MENTIONED OF ISOLATED THUNDER IN THE FORECAST PER PREV
FORECASTER SUGGESTION. BELIEVE IT COULD BE POSSIBLE AS SOUTHERN NEW
ENGLAND WILL BE IN THE WARM SECTOR...WITH THE ANOMALOUS JET AND
SHOWALTERS CLOSE TO ZERO.

FRIDAY...LOW CONFIDENCE.

ONCE UPPER LEVEL LOW MOVES INTO SOUTHERN CANADA...EXPECT A RATHER
FAST UPPER W FLOW IN PLACE. MAY SEE LEFTOVER SNOW SHOWERS BUT TEMPS
WILL FALL BACK CLOSE TO SEASONAL NORMS.

&&

.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH SUNDAY/...

700 AM UPDATE...

TODAY...MODERATE CONFIDENCE.  MVFR CIGS WILL CONTINUE TO OVERSPREAD
EASTERN NEW ENGLAND THIS MORNING AND EVENTUALLY INTO THE INTERIOR
THIS AFTERNOON.  SCATTERED PRECIPITATION WILL OVERSPREAD
SOUTHEAST MA/CAPE/ISLANDS THIS AFTERNOON.  PTYPE MAINLY SNOW SHOWERS
NORTHWEST OF THE SOUTHEAST PLYMOUTH COUNTY COAST AND RAIN SHOWERS
SOUTHEAST OF THAT REGION. LOCALIZED IFR CONDITIONS POSSIBLE JUST
INLAND FROM THE SOUTHEAST NEW ENGLAND COAST...WHERE PTYPE IS SNOW.

TONIGHT AND SUNDAY...MODERATE CONFIDENCE.  MVFR CONDITIONS DOMINATE
IN LOWER CLOUDS AND SCATTERED PRECIPITATION.  LOCALIZED IFR
CONDITIONS POSSIBLE WITH THE BEST CHANCE IN SNOW SHOWERS.
PRECIPITATION AFFECTS MAINLY EASTERN NEW ENGLAND BUT STILL SOME
SCATTERED ACTIVITY ACROSS WESTERN NEW ENGLAND. PTYPE MAINLY SNOW
SHOWERS NORTHWEST OF THE SOUTHEAST PLYMOUTH COUNTY COAST...WITH RAIN
SHOWERS SOUTHEAST OF THAT REGION.

KBOS TERMINAL...MODERATE CONFIDENCE IN TAF.  SNOW SHOWERS MAY ARRIVE
TOWARDS 00Z THIS EVENING.

KBDL TERMINAL...MODERATE CONFIDENCE IN TAF.

OUTLOOK...SUNDAY NIGHT THROUGH WEDNESDAY...

MONDAY INTO TUESDAY...MODERATE CONFIDENCE. EXPECT MOSTLY
VFR...ISOLATED MVFR ALONG THE MASS EAST COASTLINE IN RAIN/SNOW
SHOWERS.

TUESDAY NIGHT INTO WEDNESDAY...MODERATE CONFIDENCE. CONDITIONS WILL
BE DETERIORATING AS HEAVY DOWNPOURS...ISO THUNDER AND GUSTY SOUTHERLY
WINDS MOVE INTO THE REGION BY WEDNESDAY. COULD SEE MVFR TO IFR
CONDITIONS IN CIGS AND VSBYS.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /TODAY THROUGH SUNDAY/...HIGH CONFIDENCE.

HIGH PRESSURE ACROSS QUEBEC WILL RESULT IN PERSISTENT NORTHEAST
WINDS ACROSS THE WATERS THROUGH THE WEEKEND.  WIND GUSTS UP TO 20
KNOTS WITH SEAS BETWEEN 2 AND 4 FEET ARE EXPECTED FOR MOST
WATERS...SO NO HEADLINES PLANNED. THERE IS A LOW PROBABILITY THAT A
BRIEF SURGE OF NORTHEAST WIND GUSTS NEAR 25 KNOTS WITH MARGINAL 5
FOOT SEAS COULD AFFECT OUR NORTHERN WATERS LATE TONIGHT INTO SUN
MORNING...BUT NOT CONFIDENT ENOUGH TO ISSUE ANY HEADLINES AT THIS
POINT.

OUTLOOK...SUNDAY NIGHT INTO WEDNESDAY...MODERATE TO HIGH
CONFIDENCE.

SUNDAY INTO MONDAY. CONTINUOUS NORTHEAST FLOW WILL KEEP SEAS CHOPPY.
LINGERING NORTHEAST SWELL MAY BUMP SEAS ABOVE 5FT ESP ACROSS THE
NORTHEASTERN WATERS. SCA MAY BE NEEDED...BUT LOWER CONFIDENCE.

TUESDAY INTO WEDNESDAY...NE WINDS WILL INCREASE...GUSTING TO 30 KT
TUE THEN SHIFT TO SE GUSTING TO 30-35 KT WED...HIGHEST ON THE OUTER
WATERS. SEAS BUILD UP TO 7-11 FT BY WED. GALES WILL BE NEEDED.

&&

.TIDES/COASTAL FLOODING...
HIGH ASTRONOMICAL TIDES WILL OCCUR TUESDAY THROUGH THURSDAY. BREAKING
IT DOWN...ON TUESDAY HIGH TIDE AT BOSTON WILL BE 11.6 FT. THERE WILL
BE ONSHORE FLOW DURING THIS HIGH TIDE ALLOWING FOR MINOR SPLASHOVER.
IF WIND GUSTS INCREASE THEN COULD POSSIBLE SEE MINOR COASTAL
FLOODING.

ON WEDNESDAY...WINDS WILL SWITCH TO A MORE SOUTHEASTERLY FLOW DURING
THE DAY AND INCREASE QUICKLY FROM APPROACHING SYSTEM AND DESCENT
PRESSURE FALLS. WEDNESDAY AFTERNOON HIGH TIDE IN BOSTON IS 11.7 FT
AND WITH ANY STRENGTH ON THE EASTERLY WIND FLOW WILL PUSH THE TIDE
OVER. RIGHT NOW BELIEVE MINOR COASTAL FLOODING IS POSSIBLE ALONG THE
EAST COASTLINE. HOWEVER WEDNESDAY EVENING...THE WIND GOES IN A MORE
SOUTHERLY DIRECTION AND HIGH TIDE IN PROVIDENCE WILL BE 5.2 FT. 925
MB LLJ STRENGTHENS TO 50-60 KTS WHICH COULD PUSH A DESCENT SURGE UP
ALONG THE SOUTH COAST DURING THE TIME OF HIGH TIDE. THINKING THAT
MINOR COASTAL FLOODING COULD OCCUR BUT CANNOT RULE OUT MODERATE
ALONG THE SOUTH COAST...ESP IF LLJ STRENGTHENS EVEN MORE.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...FRANK/DUNTEN
NEAR TERM...FRANK/DUNTEN
SHORT TERM...FRANK
LONG TERM...DUNTEN
AVIATION...FRANK/DUNTEN
MARINE...FRANK/DUNTEN
TIDES/COASTAL FLOODING...




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