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000
FXAK67 PAJK 240050
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
350 PM AKST SUN NOV 23 2014

.SHORT TERM...CHALLENGE IS HOW MUCH SURFACE DEVELOPMENT OFF PRINCE
OF WALES ISLAND BY 24/12Z MON. OPS MODELS HAVE COME BACK INTO
AGREEMENT THAT A CLOSED LOW AROUND 1003 MB WILL BE OFF DALL ISL BY
24/12Z. THE 23/12Z AK-GFS-40 WAS PREFERRED FOR THE PRESSURE FIELD
AND THE 15Z SREF POPS WERE USED. MODERATED QPF USING THE GFS AND
TEMPS/THICKNESS INDICATED THAT SNOW LEVELS WILL REMAIN ABOVE THE
LOWLANDS SO INDICATED SNOW ONLY FOR WHITE PASS AND THE UPPER
HAINES HIGHWAY AND UPPER GLACIER BAY THROUGH MONDAY.

.LONG TERM...SOUTHWEST ONSHORE FLOW WITH SOME OROGRAPHIC
ENHANCEMENT WILL MAINTAIN SHOWERS IN THE FORECAST THROUGH THE
FIRST HALF OF THE WEEK. AT THE SAME TIME...MODELS SHOW LOWERING
HEIGHTS AND COOLING TEMPS WITH MINS FALLING TO AROUND FREEZING.
THIS MAKES THE PTYPE FCST MORE CHALLENGING. GIVEN THAT SHOWERS ARE
DIMINISHING...MOST PRECIP SHOULD FALL AS RAIN...BUT CANNOT RULE
OUT SOME SNOW MIXING IN ESPECIALLY DURING THE OVERNIGHT TUE INTO
WED.

NEXT FEATURE OF INTEREST WILL BE THE BUILDING RIDGE OVER THE GULF
OF AK AS ANOTHER TROUGH DEEPENS OVER THE BERING SEA. THIS BUILDING
RIDGE WILL RESULT IN DRIER WX AS NORTHERLY WINDS DEVELOP ACROSS SE
AK. EARLY ANALYSIS SHOWS POTENTIAL FOR SOME OUTFLOW WINDS
DEVELOPING WED INTO THU. FORECAST PRESSURE GRADIENTS RANGE AROUND
4-5MB BETWEEN PAGY/PAJN WED NIGHT INTO THU. THEREFORE...INCREASED
WINDS ACROSS LYNN CANAL AND TAKU INLET TO STRONG SCA/GALES. OTHER
CONCERN FOR THE SECOND HALF OF THE WEEK WILL BE TEMPS. GFS MOS
SHOWS LOW TEMPS IN THE SINGLE DIGITS WITH HIGHS IN THE LOW TO MID
20S HEADING INTO NEXT WEEKEND. EC MOS SUGGESTS WARMER
TEMPS...HOWEVER EC AND GFS ENSEMBLE MOS SUPPORT THE COOLER TEMPS.
LOWERED TEMPS ACROSS SE AK LATE THIS WEEK INTO THE WEEKEND
TRENDING TOWARDS THE ENSEMBLE MOS 50TH PERCENTILE TEMPS.

FORECAST CONFIDENCE AVERAGE TO ABOVE AVERAGE THROUGH THE FIRST
HALF OF THE WEEK...THEN DETERIORATES TO BELOW AVERAGE HEADING
INTO THE WEEKEND.

&&

.AVIATION...HARD TO GET RID OF SOME IFR FOG THIS MORNING DUE TO
TRAPPED MOISTURE AND SOME OF THE SHOWERS SO FAR TODAY HAVE
DROPPED CONDS TO MFVR BOTH CIGS/VSBY PARTICULARLY PAYA PASI PAKT.
AFTERNOON TAFS WILL HAVE TO ACCOUNT FOR SHOWERS AT THE LAST MINUTE
AND WILL INDICATE LOWER TREND IN CONDS LATER TONITE IF FOR NO
OTHER REASON THAN CLOSING DEW POINTS.

&&

.MARINE...SEA STATE ANALYSIS INDICATES A WIDESPREAD SWELL 8 TO 11
FT IN ALL OUTSIDE WATERS AND EXPECT THIS TO PERSIST THROUGH MON.
AS THE LOW DEVELOPS MOVING UP TO DIXON ENTRANCE WENT NEAR GALE
WITH GALE FORCE GUSTS FOR CLARENCE AND SUMNER. NORTHERLIES WILL
BEGIN INCREASING WED AFTERNOON AS OFFSHORE FLOW DEVELOPS. FORECAST
PRESSURE GRADIENTS SUPPORT NEAR GALE TO GALE FORCE WINDS WED INTO
THU.

&&

.HYDROLOGY...THIS MORNINGS FREEZING LEVELS WERE 2000-3000FT WITH
MINOR LOWERING EXPECTED THROUGH MON. PRECIP TOTALS IN SOME OF THE
MORE RAINY LOCATIONS WILL BE 1-2 INCHES ESPECIALLY SOUTHERN
PANHANDLE. NO HYDRO PROBLEMS EXPECTED.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...SMALL CRAFT ADVISORY FOR PKZ012-031-034>036-041-043-051-052.
         SMALL CRAFT ADVISORY DUE TO SEAS FOR PKZ022-042-053.

&&

$$

JC/BC

VISIT US AT HTTP://WWW.WEATHER.GOV/JUNEAU








000
FXAK67 PAJK 231449
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
549 AM AKST SUN NOV 23 2014

.SHORT TERM...WEAK UPPER LEVEL SHORTWAVE TROUGH IS MOVING INTO
SWRN B.C. THIS MORNING. ENHANCED AREA OF ASCENT ON ITS NRN
PERIPHERY SUPPORTED A BRIEF PERIOD OF HEAVY RAINFALL IN
KETCHIKAN DURING THE EARLY MORNING...BUT RATES ARE QUICKLY
DIMINISHING AS THE WAVES MOVES E. FARTHER N...MINOR WAVES OF
ASCENT CONTINUE TO SPREAD ACROSS THE NRN/CNTRL PANHANDLE...AND
WILL YIELD BANDS OF SHOWERS THROUGH THIS AFTERNOON AND TONIGHT.
SMALL CRAFT SEAS RANGING FROM 9-11 FEET ARE PRESENT OVER THE
OUTSIDE WATERS...AND ARE FORECAST TO PERSIST THROUGHOUT THE SHORT
TERM PERIOD.

LATER THIS AFTERNOON INTO TONIGHT...AN UPPER TROUGH WILL MOVE
ACROSS THE N PAC WITH MODEST HEIGHT RISES OCCURRING DOWNSTREAM
FROM THE NERN PAC INTO SWRN CANADA. THIS WILL TIGHTEN THE UPPER
HEIGHT GRADIENT RESULTING IN A WSWLY 300 MB JET STREAK
STRENGTHENING TO AROUND 170 KT. A VORTICITY STREAMER WILL FORM
ALONG THE CYCLONIC SIDE OF THIS JET AND AID IN MODEST SURFACE
CYCLOGENESIS OVER THE SERN GULF TONIGHT. THE POSITION AND
ULTIMATE MAGNITUDE OF THIS LOW IS STILL UNCERTAIN. THE GEM
PRODUCES A DEEPER AND SLOWER SOLUTION...THE GFS AND HI-RES ARW/NMM
ARE FARTHEST S AND MOST PROGRESSIVE...WHILE THE NAM/ECMWF DEVELOP
A LOW THAT LIFTS NNE ALONG THE COAST OF THE PANHANDLE. GIVEN THE
NAM/EC ROUGHLY RESIDE IN BETWEEN THE ENVELOPE OF MODEL
SOLUTIONS...DECIDED TO GO WITH THEIR GUIDANCE. AS A RESULT...SMALL
CRAFT WINDS ARE FORECAST TO DEVELOP LATE TONIGHT OVER MARINE ZONES
41 AND 42 AS WELL AS CLARENCE STRAIT. ATTM...EXPECT WIND GUSTS FOR
LAND ZONES 27 AND 28 TO FALL SHY OF STRONG WIND CRITERIA. IN
ADDITION...A ZONE OF STRENGTHENING LOW-LEVEL WAA OCCURRING AHEAD
OF THE LOW WILL SUPPORT ANOTHER ROUND OF MODERATE RAINFALL RATES
OVER THE SRN PANHANDLE.

.LONG TERM...THE SURFACE LOW DISCUSSED ABOVE WILL PUSH ONSHORE
AND FILL SOMEWHERE IN THE NORTH/CENTRAL PANHANDLE MONDAY MORNING.
THE RESULTING GRADIENT OVER THE SOUTH WILL KEEP SOLID SMALL CRAFTS
GOING FOR CLARENCE STRAIT AND MINIMUM SMALL CRAFT FOR SOUTHERN
CHATHAM AND SUMNER STRAITS. IN ADDITION HIGH SEAS ABOVE 10 FEET
WILL PERSIST IN THE LOW`S WAKE FOR ZONES 41 AND 42 WITH WINDS
TURNING A MORE SOUTHWESTERLY DIRECTION. A TONGUE OF WARM AIR WILL
HAVE SWEPT ACROSS THE PANHANDLE ALONG WITH ASSOCIATED ASCENT. THIS
WILL KEEP THE RAINFALL STRATIFORM PERHAPS FOR THE ENTIRE DAY.
HOWEVER, THE FORECAST TRANSITIONS TO SHOWERS TO COVER ANY
INSTABILITY TRYING TO WORK ITS WAY BEHIND THE SYSTEM.

SOUTHWEST ONSHORE FLOW WITH SOME OROGRAPHIC ENHANCEMENT WILL KEEP
SHOWERS IN THE FORECAST THROUGH THE EARLY WEEK WHILE AT THE SAME
TIME ATMOSPHERIC THICKNESSES SLOWLY DECREASE. AS A PROXY TO
MEASURE THE OVERALL LAYER TEMPERATURE FOR THE ATMOSPHERE, WE LOOK
FOR THICKNESSES, OR TEMPERATURES, LOW ENOUGH TO SUPPORT SNOW
THROUGH THE ENTIRE COLUMN. AT THIS TIME, MODEL THICKNESSES ARE
MARGINAL AT BEST FOR SNOW. SINCE SHOWERS WILL BE DIMINISHING DURING
THE SAME PERIOD AS THICKNESSES WILL BE FALLING, DESPITE FORECAST
LOW TEMPERATURES FALLING JUST BELOW FREEZING, THESE LOW
TEMPERATURES ARE LIKELY TO BE REACHED BETWEEN SHOWERS, AND MOST OF
THE PRECIPITATION SHOULD FALL AS RAIN. HOWEVER, MONDAY MORNING
CANNOT RULE OUT THE POSSIBILITY OF A FEW FLAKES MIXING IN OVER THE
NORTHERN PANHANDLE, BUT IMPACTS SHOULD BE MINIMAL. CONFIDENCE
GROWS FOR SNOWFLAKES MIXING IN WITH RESIDUAL SHOWERS TUESDAY
NIGHT AS 1000-850 MB THICKNESSES BEGIN TO CROSS A 1290-METER
RUBICON.

AS THE UPPER LEVEL RIDGE AXIS PASSES EAST OF SOUTHEAST ALASKA
TUESDAY NIGHT, THE ATMOSPHERE DRIES OUT QUICKLY. RIGHT NOW THE
HOLIDAY LOOKS DRY AND CLOUDS LOOK TO PART. HOWEVER, THIS USUALLY
MEANS FALLING TEMPERATURES THIS TIME OF YEAR. THEREFORE WE HAVE
DROPPED INTERIOR TEMPERATURES WELL INTO THE 20S ACROSS THE
PANHANDLE AND FREEZING TEMPERATURES EVEN TO THE FAR SOUTHERN
COAST. THE RIDGE LOOKS TO PERSIST OVER THE GULF IN SOME FORM OR
ANOTHER THROUGH THE EARLY WEEKEND WHEN PERHAPS A BREAKDOWN BEGINS
TO OCCUR. HOWEVER, GUIDANCE IS NOTORIOUSLY QUICK TO BREAK DOWN
REX BLOCKS. SO CONFIDENCE DROPS FOR THE WEEKEND. ONE DETERMINISTIC
SOLUTION ADVOCATED BY THE ECMWF LOOKS VERY INTERESTING FOR EARLY
NEXT WEEK: A SHORTWAVE DRIVES SOUTHWEST FROM THE NORTHERN BERING
SEA ACROSS THE ALASKA PENINSULA TO SPAWN A SURFACE LOW IN THE
NORTHERN GULF. WITH COLDER AIR HAVING ALREADY SETTLED, A SIGNATURE
SUCH AS THIS USUALLY MEANS SIGNIFICANT SNOW FOR THE NORTHERN
PANHANDLE, BUT THIS IS ONE OF MANY DIVERGENT SOLUTIONS AND WILL
LIKELY BE GONE IN THE MODEL`S NEXT RUN.

FORECAST CONFIDENCE IMPROVING THROUGH THE WEEK INTO THE THANKSGIVING
HOLIDAY WITH A DRYING/COOLING TREND. CONFIDENCE STARTS TO FALL FOR
THE WEEKEND.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...SMALL CRAFT ADVISORY FOR PKZ012-035-036-041-042-052.
         SMALL CRAFT ADVISORY DUE TO SEAS FOR PKZ043-051.

&&

$$

GARNER/ADKINS

VISIT US AT HTTP://WWW.WEATHER.GOV/JUNEAU












000
FXAK67 PAJK 231449
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
549 AM AKST SUN NOV 23 2014

.SHORT TERM...WEAK UPPER LEVEL SHORTWAVE TROUGH IS MOVING INTO
SWRN B.C. THIS MORNING. ENHANCED AREA OF ASCENT ON ITS NRN
PERIPHERY SUPPORTED A BRIEF PERIOD OF HEAVY RAINFALL IN
KETCHIKAN DURING THE EARLY MORNING...BUT RATES ARE QUICKLY
DIMINISHING AS THE WAVES MOVES E. FARTHER N...MINOR WAVES OF
ASCENT CONTINUE TO SPREAD ACROSS THE NRN/CNTRL PANHANDLE...AND
WILL YIELD BANDS OF SHOWERS THROUGH THIS AFTERNOON AND TONIGHT.
SMALL CRAFT SEAS RANGING FROM 9-11 FEET ARE PRESENT OVER THE
OUTSIDE WATERS...AND ARE FORECAST TO PERSIST THROUGHOUT THE SHORT
TERM PERIOD.

LATER THIS AFTERNOON INTO TONIGHT...AN UPPER TROUGH WILL MOVE
ACROSS THE N PAC WITH MODEST HEIGHT RISES OCCURRING DOWNSTREAM
FROM THE NERN PAC INTO SWRN CANADA. THIS WILL TIGHTEN THE UPPER
HEIGHT GRADIENT RESULTING IN A WSWLY 300 MB JET STREAK
STRENGTHENING TO AROUND 170 KT. A VORTICITY STREAMER WILL FORM
ALONG THE CYCLONIC SIDE OF THIS JET AND AID IN MODEST SURFACE
CYCLOGENESIS OVER THE SERN GULF TONIGHT. THE POSITION AND
ULTIMATE MAGNITUDE OF THIS LOW IS STILL UNCERTAIN. THE GEM
PRODUCES A DEEPER AND SLOWER SOLUTION...THE GFS AND HI-RES ARW/NMM
ARE FARTHEST S AND MOST PROGRESSIVE...WHILE THE NAM/ECMWF DEVELOP
A LOW THAT LIFTS NNE ALONG THE COAST OF THE PANHANDLE. GIVEN THE
NAM/EC ROUGHLY RESIDE IN BETWEEN THE ENVELOPE OF MODEL
SOLUTIONS...DECIDED TO GO WITH THEIR GUIDANCE. AS A RESULT...SMALL
CRAFT WINDS ARE FORECAST TO DEVELOP LATE TONIGHT OVER MARINE ZONES
41 AND 42 AS WELL AS CLARENCE STRAIT. ATTM...EXPECT WIND GUSTS FOR
LAND ZONES 27 AND 28 TO FALL SHY OF STRONG WIND CRITERIA. IN
ADDITION...A ZONE OF STRENGTHENING LOW-LEVEL WAA OCCURRING AHEAD
OF THE LOW WILL SUPPORT ANOTHER ROUND OF MODERATE RAINFALL RATES
OVER THE SRN PANHANDLE.

.LONG TERM...THE SURFACE LOW DISCUSSED ABOVE WILL PUSH ONSHORE
AND FILL SOMEWHERE IN THE NORTH/CENTRAL PANHANDLE MONDAY MORNING.
THE RESULTING GRADIENT OVER THE SOUTH WILL KEEP SOLID SMALL CRAFTS
GOING FOR CLARENCE STRAIT AND MINIMUM SMALL CRAFT FOR SOUTHERN
CHATHAM AND SUMNER STRAITS. IN ADDITION HIGH SEAS ABOVE 10 FEET
WILL PERSIST IN THE LOW`S WAKE FOR ZONES 41 AND 42 WITH WINDS
TURNING A MORE SOUTHWESTERLY DIRECTION. A TONGUE OF WARM AIR WILL
HAVE SWEPT ACROSS THE PANHANDLE ALONG WITH ASSOCIATED ASCENT. THIS
WILL KEEP THE RAINFALL STRATIFORM PERHAPS FOR THE ENTIRE DAY.
HOWEVER, THE FORECAST TRANSITIONS TO SHOWERS TO COVER ANY
INSTABILITY TRYING TO WORK ITS WAY BEHIND THE SYSTEM.

SOUTHWEST ONSHORE FLOW WITH SOME OROGRAPHIC ENHANCEMENT WILL KEEP
SHOWERS IN THE FORECAST THROUGH THE EARLY WEEK WHILE AT THE SAME
TIME ATMOSPHERIC THICKNESSES SLOWLY DECREASE. AS A PROXY TO
MEASURE THE OVERALL LAYER TEMPERATURE FOR THE ATMOSPHERE, WE LOOK
FOR THICKNESSES, OR TEMPERATURES, LOW ENOUGH TO SUPPORT SNOW
THROUGH THE ENTIRE COLUMN. AT THIS TIME, MODEL THICKNESSES ARE
MARGINAL AT BEST FOR SNOW. SINCE SHOWERS WILL BE DIMINISHING DURING
THE SAME PERIOD AS THICKNESSES WILL BE FALLING, DESPITE FORECAST
LOW TEMPERATURES FALLING JUST BELOW FREEZING, THESE LOW
TEMPERATURES ARE LIKELY TO BE REACHED BETWEEN SHOWERS, AND MOST OF
THE PRECIPITATION SHOULD FALL AS RAIN. HOWEVER, MONDAY MORNING
CANNOT RULE OUT THE POSSIBILITY OF A FEW FLAKES MIXING IN OVER THE
NORTHERN PANHANDLE, BUT IMPACTS SHOULD BE MINIMAL. CONFIDENCE
GROWS FOR SNOWFLAKES MIXING IN WITH RESIDUAL SHOWERS TUESDAY
NIGHT AS 1000-850 MB THICKNESSES BEGIN TO CROSS A 1290-METER
RUBICON.

AS THE UPPER LEVEL RIDGE AXIS PASSES EAST OF SOUTHEAST ALASKA
TUESDAY NIGHT, THE ATMOSPHERE DRIES OUT QUICKLY. RIGHT NOW THE
HOLIDAY LOOKS DRY AND CLOUDS LOOK TO PART. HOWEVER, THIS USUALLY
MEANS FALLING TEMPERATURES THIS TIME OF YEAR. THEREFORE WE HAVE
DROPPED INTERIOR TEMPERATURES WELL INTO THE 20S ACROSS THE
PANHANDLE AND FREEZING TEMPERATURES EVEN TO THE FAR SOUTHERN
COAST. THE RIDGE LOOKS TO PERSIST OVER THE GULF IN SOME FORM OR
ANOTHER THROUGH THE EARLY WEEKEND WHEN PERHAPS A BREAKDOWN BEGINS
TO OCCUR. HOWEVER, GUIDANCE IS NOTORIOUSLY QUICK TO BREAK DOWN
REX BLOCKS. SO CONFIDENCE DROPS FOR THE WEEKEND. ONE DETERMINISTIC
SOLUTION ADVOCATED BY THE ECMWF LOOKS VERY INTERESTING FOR EARLY
NEXT WEEK: A SHORTWAVE DRIVES SOUTHWEST FROM THE NORTHERN BERING
SEA ACROSS THE ALASKA PENINSULA TO SPAWN A SURFACE LOW IN THE
NORTHERN GULF. WITH COLDER AIR HAVING ALREADY SETTLED, A SIGNATURE
SUCH AS THIS USUALLY MEANS SIGNIFICANT SNOW FOR THE NORTHERN
PANHANDLE, BUT THIS IS ONE OF MANY DIVERGENT SOLUTIONS AND WILL
LIKELY BE GONE IN THE MODEL`S NEXT RUN.

FORECAST CONFIDENCE IMPROVING THROUGH THE WEEK INTO THE THANKSGIVING
HOLIDAY WITH A DRYING/COOLING TREND. CONFIDENCE STARTS TO FALL FOR
THE WEEKEND.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...SMALL CRAFT ADVISORY FOR PKZ012-035-036-041-042-052.
         SMALL CRAFT ADVISORY DUE TO SEAS FOR PKZ043-051.

&&

$$

GARNER/ADKINS

VISIT US AT HTTP://WWW.WEATHER.GOV/JUNEAU













000
FXAK67 PAJK 230033
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
333 PM AKST SAT NOV 22 2014

.SHORT TERM...AN UPPER LEVEL DISTURBANCE WITH A WEAK SURFACE
REFLECTION HAS BEEN MOVING OVER SOUTHEAST ALASKA FROM SOUTH TO
NORTH THROUGH THE DAY. EFFECT AT THE SURFACE HAS BEEN TO ENHANCE
SHOWER ACTIVITY AND BOOST WIND SPEEDS AND GUSTS IN THE AREA. THE
PARENT LOW ASSOCIATED WITH THE OLD FRONT REMAINS WELL TO THE WEST,
QUASI-STATIONARY OVER THE ALASKAN PENINSULA. SATELLITE IMAGERY IS
SHOWING THE LOW CONTINUING TO ADVECT UNSTABLE AIR AND SHOWERS
INTO THE GULF FROM THE WEST. ATMOSPHERE IS SUFFICIENTLY UNSTABLE
TO GIVE RISE TO THUNDERSTORMS, BUT THEY HAVE SO FAR REMAINED SOUTH
OF THE GULF. MODELED CAPE AND OTHER INSTABILITY PARAMETERS
INDICATE THE ATMOSPHERE OVER THE GULF WILL REMAIN CONVECTIVE. MID
LEVEL FORCING OVER THE GULF IS LACKING, HOWEVER, SO HAVE NOT
INCLUDED ANY THUNDERSTORMS IN THE AFTERNOON FORECAST.

DEEP, MOIST, SOUTHWESTERLY ONSHORE FLOW WILL KEEP SHOWER ACTIVITY
GOING THROUGH THE ENTIRE SHORT TERM FORECAST PERIOD. TO THE SOUTH
ALONG AN OLD FRONTAL BOUNDARY, A DEVELOPING WAVE WILL SPIN UP A
WEAK LOW LATE THIS EVENING OVER HAIDA GWAII, ENHANCING SHOWERS
OVER THE SOUTHERN PANHANDLE. THE DEVELOPING WAVE THAT FOLLOWS WILL
BE A BIT STRONGER AND TRACK FARTHER TO THE NORTH, BUT WILL NOT
ARRIVE UNTIL THE EARLY PORTION OF THE EXTENDED RANGE FORECAST.

TEMPERATURES OVER THE FAR NORTHERN INNER CHANNELS SUFFICIENTLY
COLD ENOUGH TO SUPPORT SNOW SHOWERS FOR AT LEAST PART OF THE
FORECAST AREA TONIGHT AND TOMORROW. HAVE 2.5 MORE INCHES IN THE FORECAST
THROUGH SUNDAY AFTERNOON FOR THE HAINES HIGHWAY TO ADD TO THE 4 INCHES
FROM FRIDAY NIGHT. HAVE 2 INCHES ALONG THE KLONDIKE HIGHWAY AS WELL.
EAGLE CREST SHOULD ALSO GET ABOUT 2 INCHES OF NEW SNOW TONIGHT WITH
ANOTHER 1.5 INCHES TOMORROW. ELSEWHERE DOWN LOW, NO ACCUMULATING
SNOW IS EXPECTED TONIGHT AND WITH SNOW LEVELS CREEPING BACK UP
TOMORROW, NONE TOMORROW EITHER.

SOUTHERLY WINDS ON THE INSIDE AND OVER THE COASTAL MARINE ZONES
GENERALLY 20 KTS OR LESS WITH SIMILAR VALUES FOR EASTERLY OUTFLOW
WINDS OUT OF CROSS SOUND AND ICY STRAIT. EXCEPTION IS COASTAL
MARINE ZONE 52, WHERE A WEAK BARRIER JET UP TO 25 KTS IS EXPECTED TO
FORM TOMORROW NEAR THE COAST AND WEST OF ICY BAY. SEAS ON THE
OUTSIDE ARE STILL RUNNING QUITE HIGH AT AROUND 13 FEET WITH MOST
OF THIS BEING A SOUTHWESTERLY SWELL AT 8 TO 11 SECONDS PERIOD.
SMALL CRAFT ADVISORIES FOR SEAS FOR THE REMAINDER OF THE COASTAL
MARINE ZONES. BRIEF WIND SPEED EXCURSIONS UP TO OR EVEN ABOVE 25
KTS POSSIBLE OVERNIGHT FOR THE INNER CHANNELS, BUT AM EXPECTING
OVERALL CONDITIONS ON THE INSIDE TO REMAIN BELOW SMALL CRAFT
LEVELS.

USED NAM FOR PRESSURE AND WIND TODAY. POP AND QPF A BLEND OF GEM
AND ECMWF. TEMPS FROM MOS AND NAM. SNOW LEVELS DERIVED FROM NAM AS
WELL. OVERALL FORECAST CONFIDENCE ABOVE AVERAGE.

.LONG TERM...MODEL SOLUTIONS CONTINUE TO DIVERGE EARLY IN THE
PERIOD WITH A MINOR SHORTWAVE ROTATING ACROSS THE PANHANDLE
RESULTING IN A BAROCLINIC LOW DEVELOPING NEAR PRINCE OF
WALES/SOUTHERN BARANOF ISLAND SUN NIGHT INTO MON MORNING. GEM
REMAINS A STRONG OUTLIER WITH SFC LOW DEEPENING TO 990MB WHILE THE
NAM BOTTOMS OUT AROUND 1002MB. MEANWHILE THE EC AND GFS DON`T
DEVELOP A CLOSED CIRCULATION WITH AN OPEN WAVE AROUND 1004MB
MOVING THROUGH MON. GIVEN THAT ALL MODELS SHOW A JET STREAK RIDING
OVER THE RIDGE TO THE SOUTH MON...THE RF QUADRANT OF THE STREAK
SUPPORTS A DEVELOPING LOW. MAIN FORECAST CHALLENGE IS THE
LOCATION OF THIS FEATURE. KEPT STRONGEST WINDS OVER THE SOUTHERN
PANHANDLE WITH THE SFC LOW PROGGED TO BEGIN MOVING INLAND NEAR
CAPE DECISION MON MORNING. KEPT WINDS BELOW STRONG WIND HEADLINE
CRITERIA BUT WOULDN`T BE SURPRISED IF CLARENCE STRAIT EXPERIENCED
GALES FROM THIS STORM. THIS DEVELOPING LOW ALONG WITH CONTINUED
DEEP ONSHORE AND DIFFLUENT FLOW ALOFT WILL MAINTAIN NUMEROUS TO
SCT SHOWERS THROUGH THE DAY BEFORE SLOWLY DIMINISHING TUE.

NEXT FEATURE OF INTEREST WILL BE ANOTHER TROUGH DEEPENING OVER THE
BERING SEA RESULTING IN A BUILDING RIDGE OVER THE GULF OF AK.
ALTHOUGH MODELS SHOW POOR RUN TO RUN CONSISTENCY WITH THIS FEATURE
ENSEMBLE MEANS CONTINUE TO FAVOR THIS DEVELOPMENT. TRENDED
FORECAST DRIER WED AND THU AS A MORE NORTHERLY FLOW DEVELOPS OVER
THE REGION. ONLY POTENTIAL FLY IN THE OINTMENT WILL BE AN UPPER
LOW S OF THE RIDGE. DEPENDING ON HOW FAR N THIS FEATURE MOVES...SOME
MOISTURE COULD SPREAD FAR ENOUGH N TO BRING SOME PRECIP TO THE
SOUTHERN PANHANDLE.

OVERALL...TRENDED FORECAST TOWARDS THE NAM MON...EC TUE AND THEN
USED WPC GUIDANCE THROUGH THE REMAINDER OF THE EXTENDED.
&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...SMALL CRAFT ADVISORY FOR PKZ012-052.
         SMALL CRAFT ADVISORY DUE TO SEAS FOR PKZ041>043-051.
&&

$$

FRITSCH/BC

VISIT US AT HTTP://WWW.WEATHER.GOV/JUNEAU






000
FXAK67 PAJK 230033
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
333 PM AKST SAT NOV 22 2014

.SHORT TERM...AN UPPER LEVEL DISTURBANCE WITH A WEAK SURFACE
REFLECTION HAS BEEN MOVING OVER SOUTHEAST ALASKA FROM SOUTH TO
NORTH THROUGH THE DAY. EFFECT AT THE SURFACE HAS BEEN TO ENHANCE
SHOWER ACTIVITY AND BOOST WIND SPEEDS AND GUSTS IN THE AREA. THE
PARENT LOW ASSOCIATED WITH THE OLD FRONT REMAINS WELL TO THE WEST,
QUASI-STATIONARY OVER THE ALASKAN PENINSULA. SATELLITE IMAGERY IS
SHOWING THE LOW CONTINUING TO ADVECT UNSTABLE AIR AND SHOWERS
INTO THE GULF FROM THE WEST. ATMOSPHERE IS SUFFICIENTLY UNSTABLE
TO GIVE RISE TO THUNDERSTORMS, BUT THEY HAVE SO FAR REMAINED SOUTH
OF THE GULF. MODELED CAPE AND OTHER INSTABILITY PARAMETERS
INDICATE THE ATMOSPHERE OVER THE GULF WILL REMAIN CONVECTIVE. MID
LEVEL FORCING OVER THE GULF IS LACKING, HOWEVER, SO HAVE NOT
INCLUDED ANY THUNDERSTORMS IN THE AFTERNOON FORECAST.

DEEP, MOIST, SOUTHWESTERLY ONSHORE FLOW WILL KEEP SHOWER ACTIVITY
GOING THROUGH THE ENTIRE SHORT TERM FORECAST PERIOD. TO THE SOUTH
ALONG AN OLD FRONTAL BOUNDARY, A DEVELOPING WAVE WILL SPIN UP A
WEAK LOW LATE THIS EVENING OVER HAIDA GWAII, ENHANCING SHOWERS
OVER THE SOUTHERN PANHANDLE. THE DEVELOPING WAVE THAT FOLLOWS WILL
BE A BIT STRONGER AND TRACK FARTHER TO THE NORTH, BUT WILL NOT
ARRIVE UNTIL THE EARLY PORTION OF THE EXTENDED RANGE FORECAST.

TEMPERATURES OVER THE FAR NORTHERN INNER CHANNELS SUFFICIENTLY
COLD ENOUGH TO SUPPORT SNOW SHOWERS FOR AT LEAST PART OF THE
FORECAST AREA TONIGHT AND TOMORROW. HAVE 2.5 MORE INCHES IN THE FORECAST
THROUGH SUNDAY AFTERNOON FOR THE HAINES HIGHWAY TO ADD TO THE 4 INCHES
FROM FRIDAY NIGHT. HAVE 2 INCHES ALONG THE KLONDIKE HIGHWAY AS WELL.
EAGLE CREST SHOULD ALSO GET ABOUT 2 INCHES OF NEW SNOW TONIGHT WITH
ANOTHER 1.5 INCHES TOMORROW. ELSEWHERE DOWN LOW, NO ACCUMULATING
SNOW IS EXPECTED TONIGHT AND WITH SNOW LEVELS CREEPING BACK UP
TOMORROW, NONE TOMORROW EITHER.

SOUTHERLY WINDS ON THE INSIDE AND OVER THE COASTAL MARINE ZONES
GENERALLY 20 KTS OR LESS WITH SIMILAR VALUES FOR EASTERLY OUTFLOW
WINDS OUT OF CROSS SOUND AND ICY STRAIT. EXCEPTION IS COASTAL
MARINE ZONE 52, WHERE A WEAK BARRIER JET UP TO 25 KTS IS EXPECTED TO
FORM TOMORROW NEAR THE COAST AND WEST OF ICY BAY. SEAS ON THE
OUTSIDE ARE STILL RUNNING QUITE HIGH AT AROUND 13 FEET WITH MOST
OF THIS BEING A SOUTHWESTERLY SWELL AT 8 TO 11 SECONDS PERIOD.
SMALL CRAFT ADVISORIES FOR SEAS FOR THE REMAINDER OF THE COASTAL
MARINE ZONES. BRIEF WIND SPEED EXCURSIONS UP TO OR EVEN ABOVE 25
KTS POSSIBLE OVERNIGHT FOR THE INNER CHANNELS, BUT AM EXPECTING
OVERALL CONDITIONS ON THE INSIDE TO REMAIN BELOW SMALL CRAFT
LEVELS.

USED NAM FOR PRESSURE AND WIND TODAY. POP AND QPF A BLEND OF GEM
AND ECMWF. TEMPS FROM MOS AND NAM. SNOW LEVELS DERIVED FROM NAM AS
WELL. OVERALL FORECAST CONFIDENCE ABOVE AVERAGE.

.LONG TERM...MODEL SOLUTIONS CONTINUE TO DIVERGE EARLY IN THE
PERIOD WITH A MINOR SHORTWAVE ROTATING ACROSS THE PANHANDLE
RESULTING IN A BAROCLINIC LOW DEVELOPING NEAR PRINCE OF
WALES/SOUTHERN BARANOF ISLAND SUN NIGHT INTO MON MORNING. GEM
REMAINS A STRONG OUTLIER WITH SFC LOW DEEPENING TO 990MB WHILE THE
NAM BOTTOMS OUT AROUND 1002MB. MEANWHILE THE EC AND GFS DON`T
DEVELOP A CLOSED CIRCULATION WITH AN OPEN WAVE AROUND 1004MB
MOVING THROUGH MON. GIVEN THAT ALL MODELS SHOW A JET STREAK RIDING
OVER THE RIDGE TO THE SOUTH MON...THE RF QUADRANT OF THE STREAK
SUPPORTS A DEVELOPING LOW. MAIN FORECAST CHALLENGE IS THE
LOCATION OF THIS FEATURE. KEPT STRONGEST WINDS OVER THE SOUTHERN
PANHANDLE WITH THE SFC LOW PROGGED TO BEGIN MOVING INLAND NEAR
CAPE DECISION MON MORNING. KEPT WINDS BELOW STRONG WIND HEADLINE
CRITERIA BUT WOULDN`T BE SURPRISED IF CLARENCE STRAIT EXPERIENCED
GALES FROM THIS STORM. THIS DEVELOPING LOW ALONG WITH CONTINUED
DEEP ONSHORE AND DIFFLUENT FLOW ALOFT WILL MAINTAIN NUMEROUS TO
SCT SHOWERS THROUGH THE DAY BEFORE SLOWLY DIMINISHING TUE.

NEXT FEATURE OF INTEREST WILL BE ANOTHER TROUGH DEEPENING OVER THE
BERING SEA RESULTING IN A BUILDING RIDGE OVER THE GULF OF AK.
ALTHOUGH MODELS SHOW POOR RUN TO RUN CONSISTENCY WITH THIS FEATURE
ENSEMBLE MEANS CONTINUE TO FAVOR THIS DEVELOPMENT. TRENDED
FORECAST DRIER WED AND THU AS A MORE NORTHERLY FLOW DEVELOPS OVER
THE REGION. ONLY POTENTIAL FLY IN THE OINTMENT WILL BE AN UPPER
LOW S OF THE RIDGE. DEPENDING ON HOW FAR N THIS FEATURE MOVES...SOME
MOISTURE COULD SPREAD FAR ENOUGH N TO BRING SOME PRECIP TO THE
SOUTHERN PANHANDLE.

OVERALL...TRENDED FORECAST TOWARDS THE NAM MON...EC TUE AND THEN
USED WPC GUIDANCE THROUGH THE REMAINDER OF THE EXTENDED.
&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...SMALL CRAFT ADVISORY FOR PKZ012-052.
         SMALL CRAFT ADVISORY DUE TO SEAS FOR PKZ041>043-051.
&&

$$

FRITSCH/BC

VISIT US AT HTTP://WWW.WEATHER.GOV/JUNEAU





000
FXAK67 PAJK 221440
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
540 AM AKST SAT NOV 22 2014

.SHORT TERM...BROAD UPPER LOW IS OBSERVED IN WV IMAGERY THIS
MORNING CENTERED OVER THE SWRN TIP OF THE AK PENINSULA. POLAR JET
RESIDES S OF THIS FEATURE...AND SPREADS EWD INTO ORE/WA. MIDLEVEL
VORT LOBE POSITIONED OVER THE CNTRL GULF IS ADVANCING N AND E
AROUND THE UPPER LOW. A PIECE OF THIS FEATURE WILL SHEAR EWD INTO
SERN AK THIS AFTERNOON/EVENING...LIKELY AIDING IN A MORE ORGANIZED
BAND OF SHOWERS. MIDLEVEL LAPSE RATES ARE STEEP ACROSS THE REGION
GIVEN THE PRESENCE OF H5 TEMPERATURES AROUND -32C. AS A
RESULT...WEAK MUCAPE VALUES ARE WIDESPREAD. THIS POTENTIAL
INSTABILITY COULD SUPPORT AN ISOLATED THUNDERSTORM OVER THE GULF
WATERS AND ADJACENT COAST. HOWEVER...THE COMBINATION OF
RELATIVELY COLD WATER TEMPERATURES /AROUND 9C/...AND WEAK FORCING
FOR ASCENT ASSOCIATED WITH THE PREVIOUSLY MENTIONED UPPER VORT
LOBE MAKES THE OVERALL PROBABILITY TOO LOW TO INCLUDE IN THE SHORT
TERM FORECAST.

THOUGH SURFACE ISOBARS ARE GENERALLY ORIENTED PARALLEL TO N-S
CHANNELS...SOME ENHANCEMENT TO SLY WINDS IS EXPECTED OVER LYNN
CANAL AND STEPHENS PASSAGE THROUGH THIS AFTERNOON/EVENING AS THE
DISTURBANCE OVER THE GULF APPROACHES THE CNTRL PANHANDLE. CURRENT
FORECAST CALLS FOR SLYS TO 20 KT...WITH WEAKENING OCCURRING OVERNIGHT.
ONLY MARINE HAZARD CONTINUES TO BE SMALL CRAFT SEAS OVER THE
OUTSIDE WATERS. SOME BREAKS IN MIDLEVEL CLOUD COVER WILL BE
POSSIBLE OVER THE SRN HALF OF THE PANHANDLE TONIGHT AS PRIMARY
BAND OF SHOWERS PASSES E WITH THE DISSIPATING UPPER WAVE. THIS MAY
YIELD ENHANCED RADIATIONAL COOLING AT THE SURFACE...AND WHEN
COMBINED WITH RECENT RAINFALL...WOULD INCREASE THE PROBABILITY FOR
FOG. HOWEVER...THIS SCENARIO COULD BE OFFSET BY THE STEEP LAPSE
RATE/CONVECTIVE ENVIRONMENT. DESPITE THIS CAVEAT...INCLUDED PATCHY
FOG FROM JUNEAU S TO KETCHIKAN LATE TONIGHT.

.LONG TERM...WHILE THE BROAD UPPER LOW NOTED ABOVE AGES IN PLACE
OVER THE FAR WESTERN GULF, THE RESULTANT ONSHORE FLOW PATTERN
OVER SOUTHEAST ALASKA WILL CONTINUE TO DIRECT SHOWERS OVER THE
PANHANDLE FOR SUNDAY. BUT LOOKING WESTWARD ACROSS THE PACIFIC TWO
OTHER CHARACTERS WILL ALSO IMPACT SOUTHEAST`S WEATHER, ONE
POTENTIALLY SHIFTING US TO A DRIER PATTERN BY MIDWEEK.

THE FIRST IS A SHORT-WAVE CURRENTLY DROPPING SOUTH ACROSS THE
ALEUTIANS INTO THE NORTH PACIFIC AROUND 45 N 175 W. THIS SHORTWAVE
WILL LATCH ON TO A 175 KT SOUTHWESTERLY JET DEVELOPING ACROSS THE
PACIFIC WHICH WILL USHER IT INTO THE SOUTHEASTERN GULF SUNDAY
NIGHT. A BAROCLINIC LOW WILL FORM ALONG THIS WAVE AS IT ARRIVES
SOMEWHERE CLOSE TO PRINCE OF WALES ISLAND/DIXON ENTRANCE LATE
SUNDAY NIGHT/EARLY MONDAY MORNING. THIS IS A NEW FEATURE THAT THE
MODELS HAVE RESOLVED AND MAKES SENSE WITH ITS DEVELOPMENT, GIVEN
ITS POSITION EXITING THE JET ALONG A REGION OF CLOSELY PACKED
ISOTHERMS. THE MAIN UNCERTAINTY IS PATH AND TO SOME DEGREE ITS
STRENGTH. THE ECMWF AT THIS JUNCTURE SEEMS A LITTLE WEAK WITH THE
FEATURE AND FARTHER SOUTH AND EAST THAN THE OTHER SOLUTIONS. AS
THE GEM ADVERTISED A SLIGHTLY STRONGER FEATURE AT 997 MB, WE
PREFERRED THE MIDDLE GROUND OF THE 06Z NAM AND THE 00Z GFS.
DESPITE A LOWER LEVEL JET AT 925 MB OF 40 KT, WE HELD CLARENCE
STRAIT TO 25 KT SINCE THE WARM AIR ADVECTION ASSOCIATED WITH IT
SHOULD MITIGATE MOMENTUM DOWN TO THE SURFACE. IN TURN WE DID
RAISE WIND SPEEDS TO 15 TO 25 MPH FOR ZONE 27, BUT DID NOT INCLUDE
GUSTS AT THIS POINT DUE TO INCREASING STABILITY. THIS FEATURE WILL
DAMPEN CONVECTION ACROSS THE NORTHERN PANHANDLE WITH SOME OFFSHORE
COMPONENT WINDS DEVELOPING, BUT WILL PERHAPS SPREAD SOME HEAVIER
RAINS FOR THE FAR SOUTHERN ZONES LATE SUNDAY NIGHT.

ANOTHER FEATURE JUMPING OFFSHORE FROM THE SIBERIAN COAST WILL REV
UP AS IT TAPS MOISTURE FROM THE PHILIPPINES. THIS DEEPENING LOW
WILL PROP UP THE RIDGE TO ITS EAST ESCORTING THE LOW INTO THE BERING
SEA. AS IT DOES SO, THE FORWARD MOMENTUM WILL PUSH THE FORMER
GULF UPPER LOW, NOW A TROUGH TO THE EAST. AS THE TROUGH PASSES THE
PANHANDLE, SOMETIME AROUND MID-WEEK, A DRYING PERIOD COULD EMERGE
WITH SOME CONTINUING COOLING AS WELL. BUT UNCERTAINTY STILL EXISTS
AS A THIRD PLAYER IN THE FORM OF CUT-OFF LOW TO THE SOUTH COULD
POTENTIALLY SPREAD MOISTURE LATE IN THE WEEK NORTHWARD. SO AT THIS
TIME, KEEPING RAIN LIKELY TO END THE WEEK, ESPECIALLY FOR THE
SOUTHERN PANHANDLE WITH A CHANCE FOR THE NORTH.

1000 TO 850 MB THICKNESSES STILL GREAT ENOUGH TO SEEMINGLY PREVENT
MOST RAIN SHOWERS FROM BEING MIXED WITH SNOW IN THE NEAR TERM. BUT
THEY DO DECREASE SLOWLY THROUGH EARLY NEXT WEEK. HOWEVER, THIS
COOLING IS LIKELY TO BE ACCOMPANIED BY A DIMINISHING TREND IN THE
SHOWERS. THUS WHILE A FEW FLAKES ARE NOT OUT OF THE QUESTION, A
FIRST BIG SHOVEL-DESERVING SNOW DOES NOT APPEAR TO BE IN THE CARDS
LEADING INTO THE BIG HOLIDAY.

USED 00Z GFS/06Z NAM FOR WIND UPDATES SUNDAY NIGHT INTO MONDAY
MORNING. NUDGED TO 00Z GFS FOR TUESDAY/WEDNESDAY TO CONTINUE A
DRYING TREND MID-WEEK. FORECAST CONFIDENCE GOOD THROUGH
MONDAY...INCREASING FOR MID-WEEK BUT STILL NOT GREAT.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...SMALL CRAFT ADVISORY DUE TO SEAS FOR PKZ041>043-051-052.

&&

$$

GARNER/ADKINS

VISIT US AT HTTP://WWW.WEATHER.GOV/JUNEAU










000
FXAK67 PAJK 221440
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
540 AM AKST SAT NOV 22 2014

.SHORT TERM...BROAD UPPER LOW IS OBSERVED IN WV IMAGERY THIS
MORNING CENTERED OVER THE SWRN TIP OF THE AK PENINSULA. POLAR JET
RESIDES S OF THIS FEATURE...AND SPREADS EWD INTO ORE/WA. MIDLEVEL
VORT LOBE POSITIONED OVER THE CNTRL GULF IS ADVANCING N AND E
AROUND THE UPPER LOW. A PIECE OF THIS FEATURE WILL SHEAR EWD INTO
SERN AK THIS AFTERNOON/EVENING...LIKELY AIDING IN A MORE ORGANIZED
BAND OF SHOWERS. MIDLEVEL LAPSE RATES ARE STEEP ACROSS THE REGION
GIVEN THE PRESENCE OF H5 TEMPERATURES AROUND -32C. AS A
RESULT...WEAK MUCAPE VALUES ARE WIDESPREAD. THIS POTENTIAL
INSTABILITY COULD SUPPORT AN ISOLATED THUNDERSTORM OVER THE GULF
WATERS AND ADJACENT COAST. HOWEVER...THE COMBINATION OF
RELATIVELY COLD WATER TEMPERATURES /AROUND 9C/...AND WEAK FORCING
FOR ASCENT ASSOCIATED WITH THE PREVIOUSLY MENTIONED UPPER VORT
LOBE MAKES THE OVERALL PROBABILITY TOO LOW TO INCLUDE IN THE SHORT
TERM FORECAST.

THOUGH SURFACE ISOBARS ARE GENERALLY ORIENTED PARALLEL TO N-S
CHANNELS...SOME ENHANCEMENT TO SLY WINDS IS EXPECTED OVER LYNN
CANAL AND STEPHENS PASSAGE THROUGH THIS AFTERNOON/EVENING AS THE
DISTURBANCE OVER THE GULF APPROACHES THE CNTRL PANHANDLE. CURRENT
FORECAST CALLS FOR SLYS TO 20 KT...WITH WEAKENING OCCURRING OVERNIGHT.
ONLY MARINE HAZARD CONTINUES TO BE SMALL CRAFT SEAS OVER THE
OUTSIDE WATERS. SOME BREAKS IN MIDLEVEL CLOUD COVER WILL BE
POSSIBLE OVER THE SRN HALF OF THE PANHANDLE TONIGHT AS PRIMARY
BAND OF SHOWERS PASSES E WITH THE DISSIPATING UPPER WAVE. THIS MAY
YIELD ENHANCED RADIATIONAL COOLING AT THE SURFACE...AND WHEN
COMBINED WITH RECENT RAINFALL...WOULD INCREASE THE PROBABILITY FOR
FOG. HOWEVER...THIS SCENARIO COULD BE OFFSET BY THE STEEP LAPSE
RATE/CONVECTIVE ENVIRONMENT. DESPITE THIS CAVEAT...INCLUDED PATCHY
FOG FROM JUNEAU S TO KETCHIKAN LATE TONIGHT.

.LONG TERM...WHILE THE BROAD UPPER LOW NOTED ABOVE AGES IN PLACE
OVER THE FAR WESTERN GULF, THE RESULTANT ONSHORE FLOW PATTERN
OVER SOUTHEAST ALASKA WILL CONTINUE TO DIRECT SHOWERS OVER THE
PANHANDLE FOR SUNDAY. BUT LOOKING WESTWARD ACROSS THE PACIFIC TWO
OTHER CHARACTERS WILL ALSO IMPACT SOUTHEAST`S WEATHER, ONE
POTENTIALLY SHIFTING US TO A DRIER PATTERN BY MIDWEEK.

THE FIRST IS A SHORT-WAVE CURRENTLY DROPPING SOUTH ACROSS THE
ALEUTIANS INTO THE NORTH PACIFIC AROUND 45 N 175 W. THIS SHORTWAVE
WILL LATCH ON TO A 175 KT SOUTHWESTERLY JET DEVELOPING ACROSS THE
PACIFIC WHICH WILL USHER IT INTO THE SOUTHEASTERN GULF SUNDAY
NIGHT. A BAROCLINIC LOW WILL FORM ALONG THIS WAVE AS IT ARRIVES
SOMEWHERE CLOSE TO PRINCE OF WALES ISLAND/DIXON ENTRANCE LATE
SUNDAY NIGHT/EARLY MONDAY MORNING. THIS IS A NEW FEATURE THAT THE
MODELS HAVE RESOLVED AND MAKES SENSE WITH ITS DEVELOPMENT, GIVEN
ITS POSITION EXITING THE JET ALONG A REGION OF CLOSELY PACKED
ISOTHERMS. THE MAIN UNCERTAINTY IS PATH AND TO SOME DEGREE ITS
STRENGTH. THE ECMWF AT THIS JUNCTURE SEEMS A LITTLE WEAK WITH THE
FEATURE AND FARTHER SOUTH AND EAST THAN THE OTHER SOLUTIONS. AS
THE GEM ADVERTISED A SLIGHTLY STRONGER FEATURE AT 997 MB, WE
PREFERRED THE MIDDLE GROUND OF THE 06Z NAM AND THE 00Z GFS.
DESPITE A LOWER LEVEL JET AT 925 MB OF 40 KT, WE HELD CLARENCE
STRAIT TO 25 KT SINCE THE WARM AIR ADVECTION ASSOCIATED WITH IT
SHOULD MITIGATE MOMENTUM DOWN TO THE SURFACE. IN TURN WE DID
RAISE WIND SPEEDS TO 15 TO 25 MPH FOR ZONE 27, BUT DID NOT INCLUDE
GUSTS AT THIS POINT DUE TO INCREASING STABILITY. THIS FEATURE WILL
DAMPEN CONVECTION ACROSS THE NORTHERN PANHANDLE WITH SOME OFFSHORE
COMPONENT WINDS DEVELOPING, BUT WILL PERHAPS SPREAD SOME HEAVIER
RAINS FOR THE FAR SOUTHERN ZONES LATE SUNDAY NIGHT.

ANOTHER FEATURE JUMPING OFFSHORE FROM THE SIBERIAN COAST WILL REV
UP AS IT TAPS MOISTURE FROM THE PHILIPPINES. THIS DEEPENING LOW
WILL PROP UP THE RIDGE TO ITS EAST ESCORTING THE LOW INTO THE BERING
SEA. AS IT DOES SO, THE FORWARD MOMENTUM WILL PUSH THE FORMER
GULF UPPER LOW, NOW A TROUGH TO THE EAST. AS THE TROUGH PASSES THE
PANHANDLE, SOMETIME AROUND MID-WEEK, A DRYING PERIOD COULD EMERGE
WITH SOME CONTINUING COOLING AS WELL. BUT UNCERTAINTY STILL EXISTS
AS A THIRD PLAYER IN THE FORM OF CUT-OFF LOW TO THE SOUTH COULD
POTENTIALLY SPREAD MOISTURE LATE IN THE WEEK NORTHWARD. SO AT THIS
TIME, KEEPING RAIN LIKELY TO END THE WEEK, ESPECIALLY FOR THE
SOUTHERN PANHANDLE WITH A CHANCE FOR THE NORTH.

1000 TO 850 MB THICKNESSES STILL GREAT ENOUGH TO SEEMINGLY PREVENT
MOST RAIN SHOWERS FROM BEING MIXED WITH SNOW IN THE NEAR TERM. BUT
THEY DO DECREASE SLOWLY THROUGH EARLY NEXT WEEK. HOWEVER, THIS
COOLING IS LIKELY TO BE ACCOMPANIED BY A DIMINISHING TREND IN THE
SHOWERS. THUS WHILE A FEW FLAKES ARE NOT OUT OF THE QUESTION, A
FIRST BIG SHOVEL-DESERVING SNOW DOES NOT APPEAR TO BE IN THE CARDS
LEADING INTO THE BIG HOLIDAY.

USED 00Z GFS/06Z NAM FOR WIND UPDATES SUNDAY NIGHT INTO MONDAY
MORNING. NUDGED TO 00Z GFS FOR TUESDAY/WEDNESDAY TO CONTINUE A
DRYING TREND MID-WEEK. FORECAST CONFIDENCE GOOD THROUGH
MONDAY...INCREASING FOR MID-WEEK BUT STILL NOT GREAT.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...SMALL CRAFT ADVISORY DUE TO SEAS FOR PKZ041>043-051-052.

&&

$$

GARNER/ADKINS

VISIT US AT HTTP://WWW.WEATHER.GOV/JUNEAU











000
FXAK67 PAJK 220120
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
420 PM AKST FRI NOV 21 2014

.SHORT TERM...WEATHER FRONT HAS PUSHED THROUGH ESSENTIALLY ALL OF
SOUTHEAST ALASKA THOUGH IT MAY BE HUNG UP ALONG THE COAST OF THE
NORTHEAST GULF WEST OF YAKUTAT. WINDS HAVE LOWERED BACK TO THE 10
TO 20 KT RANGE. SATELLITE AND RADAR IMAGERY SHOW A FAIR BIT OF
SHOWER ACTIVITY OUT OVER THE GULF THAT IS TRACKING NORTH TO
NORTHEAST AND ONSHORE OF THE PANHANDLE THIS EVENING. THERE IS A
MORE ORGANIZED STRONGER BAND OUT OVER THE CENTRAL GULF OF ALASKA.
EXPECT THIS TO TRACK MORE TO END UP WEST OF THE YAKUTAT AREA IF MY
THINKING IS CORRECT. CONVECTION FOR THE GULF WATERS NOT ACTING
SIGNIFICANTLY ENOUGH TO WARRANT THUNDER...SATELLITE DETECTION IS
PICKING UP SOME STRIKES HOWEVER FURTHER TO THE SOUTH.

BIGGEST ISSUE TONIGHT WILL BE HOW THE WINDS WILL BE SWIRLING ABOUT
THROUGH THE NORTHERN INNER CHANNELS. HAVE GONE WITH THE ONSHORE
PUSH THROUGH CROSS SOUND AND MUCH OF THAT WILL TRY TO PUSH INTO THE
GLACIER BAY AREA I THINK BUT MAY NEED TO WATCH LYNN CANAL.
PRESSURE GRADIENT THERE IS ALONG THE CHANNEL SO THAT IS NOT HELPING
MUCH DIRECTION WISE. HOWEVER MAY SEE WEAK LOW PRESSURE DEVELOP OVER
THE SOUTHERN YUKON AREA WHICH WOULD LEAD TO A SOUTHERLY WIND IN
THE CANAL.

FOR THE MOMENT HAVE LEFT CHILKAT VALLEY WITH A NORTH WIND THAT
WILL KEEP THE PRECIPITATION FALLING AS SNOW IN THAT AREA. EXPECTED
AMOUNTS SHOULD BE LIGHT. OTHERWISE EXPECT PRECIPITATION TYPE TO BE
MAINLY RAIN ACROSS THE REGION TONIGHT AND SATURDAY.

.LONG TERM...MODEL DIVERGENCE BY EARLY NEXT WEEK IS SEVERE, SO
OVERALL CONFIDENCE IN THE EXTENDED RANGE FORECAST IS BELOW
AVERAGE. ADDING TO THIS, SNOW LEVEL GRIDS DID NOT WORK OUT WELL AT
ALL TODAY IN TERMS OF CORRELATING SNOW LEVELS TO SURFACE
TEMPERATURES. MANUAL ADJUSTMENTS MADE WHEN INITIAL RESULTS IN
WEATHER GRIDS DID NOT PASS THE COMMON SENSE TEST.

SHOWERS WILL REMAIN OVER SOUTHEAST ALASKA THROUGH THE WEEKEND WITH
SOME LOCATIONS GETTING SNOW. BEST CHANCES FOR ACCUMULATIONS OVER
THE FAR NORTHERN INNER CHANNELS AS WELL AS IN HYDER. SIGNIFICANT
ACCUMULATIONS NORTH OF YAKUTAT AS WELL ALONG THE SHORES OF THE
BAY. ELSEWHERE, APART FROM THE CENTRAL OUTER COAST, IT IS A VERY
FINE LINE BETWEEN RAIN AND SNOW DURING THE OVERNIGHT HOURS.

SHOWERS WILL GIVE WAY TO STRATIFORM PRECIP AROUND TUESDAY WHEN THE
NEXT SIGNIFICANT FRONT IS FORECAST TO MOVE OVER THE PANHANDLE.
WENT WITH WPC BY THIS POINT IN THE FORECAST AS MODEL GUIDANCE TOO
DIVERGENT TO USE ANY FORM OF A BLEND WITHOUT WASHING OUT ALL
DETAIL. BELIEVE THE NEXT FRONT WILL APPROACH GENERALLY FROM THE SOUTH
AND HANG UP OVER THE CENTRAL COAST. THERE WILL BE SOME COLDER AIR
AT THE SURFACE - COLD ENOUGH TO SUPPORT SNOW - BUT THE TRAJECTORY
OF THE THIS NEXT FRONT DOES NOT FAVOR SNOW FOR MOST LOCATIONS.
H850 FLOW IS FROM THE SOUTHWEST AND THICKNESS VALUES ARE TOO HIGH.
SITUATION IMPROVES LATE THURSDAY NIGHT WITH A REVERSAL OF THE LOW
LEVEL FLOW AND DIMINISHING THICKNESS VALUES. HOWEVER, GIVEN THIS
IS A DAY 7 FORECAST, A LOT CAN HAPPEN BETWEEN NOW AND THEN. THE
BIGGEST THING TO WATCH WILL BE HOW THE MODELS RESOLVE THE TUESDAY
LOW AND ASSOCIATED FRONT.




&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...SMALL CRAFT ADVISORY FOR PKZ052.
         SMALL CRAFT ADVISORY DUE TO SEAS FOR PKZ041>043-051-053.

&&

$$

BEZENEK/FRITSCH

VISIT US AT HTTP://WWW.WEATHER.GOV/JUNEAU








000
FXAK67 PAJK 220120
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
420 PM AKST FRI NOV 21 2014

.SHORT TERM...WEATHER FRONT HAS PUSHED THROUGH ESSENTIALLY ALL OF
SOUTHEAST ALASKA THOUGH IT MAY BE HUNG UP ALONG THE COAST OF THE
NORTHEAST GULF WEST OF YAKUTAT. WINDS HAVE LOWERED BACK TO THE 10
TO 20 KT RANGE. SATELLITE AND RADAR IMAGERY SHOW A FAIR BIT OF
SHOWER ACTIVITY OUT OVER THE GULF THAT IS TRACKING NORTH TO
NORTHEAST AND ONSHORE OF THE PANHANDLE THIS EVENING. THERE IS A
MORE ORGANIZED STRONGER BAND OUT OVER THE CENTRAL GULF OF ALASKA.
EXPECT THIS TO TRACK MORE TO END UP WEST OF THE YAKUTAT AREA IF MY
THINKING IS CORRECT. CONVECTION FOR THE GULF WATERS NOT ACTING
SIGNIFICANTLY ENOUGH TO WARRANT THUNDER...SATELLITE DETECTION IS
PICKING UP SOME STRIKES HOWEVER FURTHER TO THE SOUTH.

BIGGEST ISSUE TONIGHT WILL BE HOW THE WINDS WILL BE SWIRLING ABOUT
THROUGH THE NORTHERN INNER CHANNELS. HAVE GONE WITH THE ONSHORE
PUSH THROUGH CROSS SOUND AND MUCH OF THAT WILL TRY TO PUSH INTO THE
GLACIER BAY AREA I THINK BUT MAY NEED TO WATCH LYNN CANAL.
PRESSURE GRADIENT THERE IS ALONG THE CHANNEL SO THAT IS NOT HELPING
MUCH DIRECTION WISE. HOWEVER MAY SEE WEAK LOW PRESSURE DEVELOP OVER
THE SOUTHERN YUKON AREA WHICH WOULD LEAD TO A SOUTHERLY WIND IN
THE CANAL.

FOR THE MOMENT HAVE LEFT CHILKAT VALLEY WITH A NORTH WIND THAT
WILL KEEP THE PRECIPITATION FALLING AS SNOW IN THAT AREA. EXPECTED
AMOUNTS SHOULD BE LIGHT. OTHERWISE EXPECT PRECIPITATION TYPE TO BE
MAINLY RAIN ACROSS THE REGION TONIGHT AND SATURDAY.

.LONG TERM...MODEL DIVERGENCE BY EARLY NEXT WEEK IS SEVERE, SO
OVERALL CONFIDENCE IN THE EXTENDED RANGE FORECAST IS BELOW
AVERAGE. ADDING TO THIS, SNOW LEVEL GRIDS DID NOT WORK OUT WELL AT
ALL TODAY IN TERMS OF CORRELATING SNOW LEVELS TO SURFACE
TEMPERATURES. MANUAL ADJUSTMENTS MADE WHEN INITIAL RESULTS IN
WEATHER GRIDS DID NOT PASS THE COMMON SENSE TEST.

SHOWERS WILL REMAIN OVER SOUTHEAST ALASKA THROUGH THE WEEKEND WITH
SOME LOCATIONS GETTING SNOW. BEST CHANCES FOR ACCUMULATIONS OVER
THE FAR NORTHERN INNER CHANNELS AS WELL AS IN HYDER. SIGNIFICANT
ACCUMULATIONS NORTH OF YAKUTAT AS WELL ALONG THE SHORES OF THE
BAY. ELSEWHERE, APART FROM THE CENTRAL OUTER COAST, IT IS A VERY
FINE LINE BETWEEN RAIN AND SNOW DURING THE OVERNIGHT HOURS.

SHOWERS WILL GIVE WAY TO STRATIFORM PRECIP AROUND TUESDAY WHEN THE
NEXT SIGNIFICANT FRONT IS FORECAST TO MOVE OVER THE PANHANDLE.
WENT WITH WPC BY THIS POINT IN THE FORECAST AS MODEL GUIDANCE TOO
DIVERGENT TO USE ANY FORM OF A BLEND WITHOUT WASHING OUT ALL
DETAIL. BELIEVE THE NEXT FRONT WILL APPROACH GENERALLY FROM THE SOUTH
AND HANG UP OVER THE CENTRAL COAST. THERE WILL BE SOME COLDER AIR
AT THE SURFACE - COLD ENOUGH TO SUPPORT SNOW - BUT THE TRAJECTORY
OF THE THIS NEXT FRONT DOES NOT FAVOR SNOW FOR MOST LOCATIONS.
H850 FLOW IS FROM THE SOUTHWEST AND THICKNESS VALUES ARE TOO HIGH.
SITUATION IMPROVES LATE THURSDAY NIGHT WITH A REVERSAL OF THE LOW
LEVEL FLOW AND DIMINISHING THICKNESS VALUES. HOWEVER, GIVEN THIS
IS A DAY 7 FORECAST, A LOT CAN HAPPEN BETWEEN NOW AND THEN. THE
BIGGEST THING TO WATCH WILL BE HOW THE MODELS RESOLVE THE TUESDAY
LOW AND ASSOCIATED FRONT.




&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...SMALL CRAFT ADVISORY FOR PKZ052.
         SMALL CRAFT ADVISORY DUE TO SEAS FOR PKZ041>043-051-053.

&&

$$

BEZENEK/FRITSCH

VISIT US AT HTTP://WWW.WEATHER.GOV/JUNEAU









000
FXAK67 PAJK 211407
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
507 AM AKST FRI NOV 21 2014

.SHORT TERM...SHARP FRONTAL BOUNDARY APPROACHING FROM THE SOUTH CAUSING
STRONG WINDS AND INCREASED PRECIP IN SOUTHERN AND SOUTHWESTERN
AREAS AS EXPECTED. GUSTS UP TO 50KT OVER THE PAST COUPLE HOURS
HAVE OCCURRED AT A COUPLE LOCATIONS...HYDABURG AND METLAKATLA. THIS
BOUNDARY IS PRIMARILY FRONTAL AND NOT A DEVELOPING CLOSED LOW...SO
IMPACTS WILL BE BRIEF...WIND SHIFT WILL LIKELY BEGIN TO MAKE
LANDFALL OVER FAR SOUTHERN REACHES BY 16-18Z. THE IMPACTED ZONES
ARE CURRENTLY UNDER STRONG WIND WORDING IN ZONES. MEANWHILE WE ARE
STARTING OFF WITH GALES OFFSHORE IN 41-43 AND 51 THROUGH 15Z.
CLARENCE STRAIT ALSO IN GALE THROUGH 21Z. INSTABILITY IS CONFINED
TO WELL SOUTH OF OUR FORECAST AREA AS A FEW LIGHTNING HITS HAVE
OCCURRED AT 11Z SOUTH OF 50N. ON THE SHORT-RANGE MODELS INCLUDING
THE HIGH-RES VERSIONS...850MB SOUTHEASTERLY JET 35-50KT OVER THE
SOUTHERN/CENTRAL PANHANDLE UP INTO THE NORTHERN GULF IS ALREADY
WEAKENING BY 15Z AND DOWN TO 25-40 KT AT 18Z. WINDS SHOULD BEGIN
TO SUBSIDE BY LATE MORNING...BUT A SWITCH TO POSTFRONTAL
SOUTHWESTERLIES (10-15 KT WEAKER) FOR EXPOSED LOCATIONS IN OUR
SOUTHERNMOST ZONES 23, 25 AND 28 WILL LIKELY OCCUR PRIOR TO A
RELAXATION OF WINDS TO UNDER 20 KNOTS OR SO. WENT TO A POSTFRONTAL
SHOWERS SCENARIO FOR THE WESTERN PORTION OF THE SOUTHERN PANHANDLE
FROM 21Z ON. SOME NORTHERN AREAS WILL LIKELY SEE SOME BRIEF SNOW
AT THE BEGINNING OF THE PRECIP THIS MORNING AS PREEXISTING AIRMASS
IS DRY. HAINES IS THE CURRENT EXAMPLE. A SNOW/RAIN MIX IS LIKELY
FRIDAY NIGHT AT SEA LEVEL ON THE NORTHERN FRINGES AS WELL AS THE
HYDER VICINITY. MINOR ACCUMULATIONS EXPECTED. AFTER THE WEAKENING
SYSTEM MOVES ONSHORE, WE GO INTO A COUPLE DAYS OF MOIST SWLY
ONSHORE FLOW WITH CYCLONIC FLOW ALOFT AND GENERALLY WEAK WINDS.
WITH THE LACK OF AN ORGANIZED MARINE LOW...SNOWFALL MAY END UP A
BIT ENHANCED FOR THE NORTHERN AND EASTERN PORTIONS LATE TONIGHT
THAN WHAT MODEL GUIDANCE SUGGESTS AS CONTINENTAL AIR WONT BE
PUSHED INLAND AFTER A BRIEF PERIOD TODAY. ANOTHER POTENTIAL
SCENARIO IS SOME ISOLATED FOG POSSIBLE LATE TONIGHT AND EARLY
TOMORROW FOR ANY AREAS THAT HAVE PARTIAL CLEARING...NOT LIKELY BUT
WORTH KEEPING AN EYE ON.

FOR THE GRIDS, UPDATED QPF FIELDS WITH SLIGHT ADJUSTMENTS PER
NAM/EC GUIDANCE FOR LATER TODAY AND TONIGHT AND TWEAKED THE
PREDICTED WIND FIELDS ALONG THE COASTLINE FOR BETTER CONTINUITY
ACCORDING TO THE PRESSURE FIELD. MODEL CONSISTENCY HAS LED TO VERY
GOOD AGREEMENT IN THE FIELDS FOR SATURDAY MORNING WITH ONLY MINOR
ADJUSTMENTS TO PREVIOUS FORECASTS.

.LONG TERM...UPPER LOW CURRENTLY POSITIONED OVER THE SWRN TIP OF
THE AK PENINSULA IS FORECAST TO REMAIN QUASI-STATIONARY THROUGH
MON...AND THEN MOVE EWD ACROSS THE NRN GULF ON TUE BEFORE SHEARING
APART/WEAKENING OVER THE PANHANDLE TUE NIGHT INTO WED. IN THE
MEANTIME...COLD MIDLEVEL AIRMASS /H5 TEMPERATURES AROUND -33C/
WILL BE PRESENT FROM THE GULF NWWD ACROSS THE PANHANDLE. THIS
AIRMASS COMBINED WITH PERSISTENT SWLY FLOW ALOFT WILL FAVOR
SHOWERS THROUGH THE WEEKEND.

THERE WILL ALSO BE A NON-ZERO THREAT FOR AN ISOLATED THUNDERSTORM
OVER MARINE ZONES 310...41...42...AND 43 SAT AFTERNOON/EVENING.
DID NOT INCLUDE THIS POSSIBILITY IN CURRENT FORECAST DUE TO THE
OVERALL LOW PROBABILITY...BUT WILL CONTINUE TO EVALUATE IN FUTURE
FORECASTS. NO SIGNIFICANT FRONTAL SYSTEMS ARE EXPECTED TO IMPACT
THE REGION THROUGH EARLY NEXT WEEK...AND PRESSURE GRADIENT OVER
THE INSIDE CHANNELS WILL GENERALLY BE WEAK. THUS...MARINE HAZARDS
WILL BE LIMITED TO SMALL CRAFT SEAS OVER THE OUTSIDE WATERS.

BY THE MIDDLE OF NEXT WEEK...SPREAD AMONGST DETERMINISTIC MODEL
SOLUTIONS BECOMES VERY LARGE...AS THE ECMWF DEVELOPS A STRONG LOW
OVER THE NERN PAC/SERN GULF...WHILE THE GFS FAVORS A DOMINANT
RIDGE CENTERED OVER THE GULF. AS A RESULT...FORECAST UNCERTAINTY
IS CONSIDERABLE. PATTERN DOES APPEAR TO SUPPORT A GENERAL COOLING
TREND GOING INTO NEXT WEEK...WHICH WILL YIELD INCREASING
POTENTIAL FOR LIGHT SNOW OVER THE NRN HALF OF THE PANHANDLE...AS
WELL AS HYDER.

INHERITED PRESSURE GRIDS WERE LEFT UNCHANGED THROUGH 18Z
SUN...THEN ECMWF WAS BLENDED IN WITH PREVIOUS FORECAST THROUGH 12Z
MON...AFTER WHICH WPC WAS COMBINED WITH THE 00Z GFS IN ORDER TO
MAINTAIN CONSISTENCY WITH AFC BORDER. COMBINATION OF GFS AND
ECMWF WAS USED TO REFRESH POP/QPF...THROUGH MAGNITUDE OF BOTH
FIELDS WAS DECREASED BY THE MIDDLE OF NEXT WEEK DUE TO PREVIOUSLY
MENTIONED MODEL SPREAD. WEATHER GRIDS WERE UPDATED TO REFLECT
UNSTABLE SHOWER REGIME THROUGH MON.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...STRONG WIND UNTIL 9 AM AKST THIS MORNING FOR AKZ027-028.
         STRONG WIND UNTIL 6 AM AKST EARLY THIS MORNING FOR AKZ023.
MARINE...GALE WARNING FOR PKZ036-041>043-051.
         SMALL CRAFT ADVISORY FOR PKZ012-021-022-031>035-052.
         SMALL CRAFT ADVISORY DUE TO SEAS FOR PKZ053.

&&

$$

WESLEY/GARNER

VISIT US AT HTTP://WWW.WEATHER.GOV/JUNEAU







000
FXAK67 PAJK 211407
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
507 AM AKST FRI NOV 21 2014

.SHORT TERM...SHARP FRONTAL BOUNDARY APPROACHING FROM THE SOUTH CAUSING
STRONG WINDS AND INCREASED PRECIP IN SOUTHERN AND SOUTHWESTERN
AREAS AS EXPECTED. GUSTS UP TO 50KT OVER THE PAST COUPLE HOURS
HAVE OCCURRED AT A COUPLE LOCATIONS...HYDABURG AND METLAKATLA. THIS
BOUNDARY IS PRIMARILY FRONTAL AND NOT A DEVELOPING CLOSED LOW...SO
IMPACTS WILL BE BRIEF...WIND SHIFT WILL LIKELY BEGIN TO MAKE
LANDFALL OVER FAR SOUTHERN REACHES BY 16-18Z. THE IMPACTED ZONES
ARE CURRENTLY UNDER STRONG WIND WORDING IN ZONES. MEANWHILE WE ARE
STARTING OFF WITH GALES OFFSHORE IN 41-43 AND 51 THROUGH 15Z.
CLARENCE STRAIT ALSO IN GALE THROUGH 21Z. INSTABILITY IS CONFINED
TO WELL SOUTH OF OUR FORECAST AREA AS A FEW LIGHTNING HITS HAVE
OCCURRED AT 11Z SOUTH OF 50N. ON THE SHORT-RANGE MODELS INCLUDING
THE HIGH-RES VERSIONS...850MB SOUTHEASTERLY JET 35-50KT OVER THE
SOUTHERN/CENTRAL PANHANDLE UP INTO THE NORTHERN GULF IS ALREADY
WEAKENING BY 15Z AND DOWN TO 25-40 KT AT 18Z. WINDS SHOULD BEGIN
TO SUBSIDE BY LATE MORNING...BUT A SWITCH TO POSTFRONTAL
SOUTHWESTERLIES (10-15 KT WEAKER) FOR EXPOSED LOCATIONS IN OUR
SOUTHERNMOST ZONES 23, 25 AND 28 WILL LIKELY OCCUR PRIOR TO A
RELAXATION OF WINDS TO UNDER 20 KNOTS OR SO. WENT TO A POSTFRONTAL
SHOWERS SCENARIO FOR THE WESTERN PORTION OF THE SOUTHERN PANHANDLE
FROM 21Z ON. SOME NORTHERN AREAS WILL LIKELY SEE SOME BRIEF SNOW
AT THE BEGINNING OF THE PRECIP THIS MORNING AS PREEXISTING AIRMASS
IS DRY. HAINES IS THE CURRENT EXAMPLE. A SNOW/RAIN MIX IS LIKELY
FRIDAY NIGHT AT SEA LEVEL ON THE NORTHERN FRINGES AS WELL AS THE
HYDER VICINITY. MINOR ACCUMULATIONS EXPECTED. AFTER THE WEAKENING
SYSTEM MOVES ONSHORE, WE GO INTO A COUPLE DAYS OF MOIST SWLY
ONSHORE FLOW WITH CYCLONIC FLOW ALOFT AND GENERALLY WEAK WINDS.
WITH THE LACK OF AN ORGANIZED MARINE LOW...SNOWFALL MAY END UP A
BIT ENHANCED FOR THE NORTHERN AND EASTERN PORTIONS LATE TONIGHT
THAN WHAT MODEL GUIDANCE SUGGESTS AS CONTINENTAL AIR WONT BE
PUSHED INLAND AFTER A BRIEF PERIOD TODAY. ANOTHER POTENTIAL
SCENARIO IS SOME ISOLATED FOG POSSIBLE LATE TONIGHT AND EARLY
TOMORROW FOR ANY AREAS THAT HAVE PARTIAL CLEARING...NOT LIKELY BUT
WORTH KEEPING AN EYE ON.

FOR THE GRIDS, UPDATED QPF FIELDS WITH SLIGHT ADJUSTMENTS PER
NAM/EC GUIDANCE FOR LATER TODAY AND TONIGHT AND TWEAKED THE
PREDICTED WIND FIELDS ALONG THE COASTLINE FOR BETTER CONTINUITY
ACCORDING TO THE PRESSURE FIELD. MODEL CONSISTENCY HAS LED TO VERY
GOOD AGREEMENT IN THE FIELDS FOR SATURDAY MORNING WITH ONLY MINOR
ADJUSTMENTS TO PREVIOUS FORECASTS.

.LONG TERM...UPPER LOW CURRENTLY POSITIONED OVER THE SWRN TIP OF
THE AK PENINSULA IS FORECAST TO REMAIN QUASI-STATIONARY THROUGH
MON...AND THEN MOVE EWD ACROSS THE NRN GULF ON TUE BEFORE SHEARING
APART/WEAKENING OVER THE PANHANDLE TUE NIGHT INTO WED. IN THE
MEANTIME...COLD MIDLEVEL AIRMASS /H5 TEMPERATURES AROUND -33C/
WILL BE PRESENT FROM THE GULF NWWD ACROSS THE PANHANDLE. THIS
AIRMASS COMBINED WITH PERSISTENT SWLY FLOW ALOFT WILL FAVOR
SHOWERS THROUGH THE WEEKEND.

THERE WILL ALSO BE A NON-ZERO THREAT FOR AN ISOLATED THUNDERSTORM
OVER MARINE ZONES 310...41...42...AND 43 SAT AFTERNOON/EVENING.
DID NOT INCLUDE THIS POSSIBILITY IN CURRENT FORECAST DUE TO THE
OVERALL LOW PROBABILITY...BUT WILL CONTINUE TO EVALUATE IN FUTURE
FORECASTS. NO SIGNIFICANT FRONTAL SYSTEMS ARE EXPECTED TO IMPACT
THE REGION THROUGH EARLY NEXT WEEK...AND PRESSURE GRADIENT OVER
THE INSIDE CHANNELS WILL GENERALLY BE WEAK. THUS...MARINE HAZARDS
WILL BE LIMITED TO SMALL CRAFT SEAS OVER THE OUTSIDE WATERS.

BY THE MIDDLE OF NEXT WEEK...SPREAD AMONGST DETERMINISTIC MODEL
SOLUTIONS BECOMES VERY LARGE...AS THE ECMWF DEVELOPS A STRONG LOW
OVER THE NERN PAC/SERN GULF...WHILE THE GFS FAVORS A DOMINANT
RIDGE CENTERED OVER THE GULF. AS A RESULT...FORECAST UNCERTAINTY
IS CONSIDERABLE. PATTERN DOES APPEAR TO SUPPORT A GENERAL COOLING
TREND GOING INTO NEXT WEEK...WHICH WILL YIELD INCREASING
POTENTIAL FOR LIGHT SNOW OVER THE NRN HALF OF THE PANHANDLE...AS
WELL AS HYDER.

INHERITED PRESSURE GRIDS WERE LEFT UNCHANGED THROUGH 18Z
SUN...THEN ECMWF WAS BLENDED IN WITH PREVIOUS FORECAST THROUGH 12Z
MON...AFTER WHICH WPC WAS COMBINED WITH THE 00Z GFS IN ORDER TO
MAINTAIN CONSISTENCY WITH AFC BORDER. COMBINATION OF GFS AND
ECMWF WAS USED TO REFRESH POP/QPF...THROUGH MAGNITUDE OF BOTH
FIELDS WAS DECREASED BY THE MIDDLE OF NEXT WEEK DUE TO PREVIOUSLY
MENTIONED MODEL SPREAD. WEATHER GRIDS WERE UPDATED TO REFLECT
UNSTABLE SHOWER REGIME THROUGH MON.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...STRONG WIND UNTIL 9 AM AKST THIS MORNING FOR AKZ027-028.
         STRONG WIND UNTIL 6 AM AKST EARLY THIS MORNING FOR AKZ023.
MARINE...GALE WARNING FOR PKZ036-041>043-051.
         SMALL CRAFT ADVISORY FOR PKZ012-021-022-031>035-052.
         SMALL CRAFT ADVISORY DUE TO SEAS FOR PKZ053.

&&

$$

WESLEY/GARNER

VISIT US AT HTTP://WWW.WEATHER.GOV/JUNEAU








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