000
FXUS61 KPBZ 220453
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
1253 AM EDT TUE MAY 22 2012

.SYNOPSIS...
A FRONTAL BOUNDARY WILL SLOWLY MOVE ACROSS THE AREA INTO TUESDAY.
SHOWERS AND THUNDERSTORMS WILL RE-DEVELOP ALONG AND AHEAD OF THE
FRONT TUESDAY AFTERNOON AND CONTINUE INTO TUESDAY NIGHT. WARM
WEATHER CAN BE EXPECTED TO CONTINUE WITH HUMIDITY INCREASING LATE
THIS WEEK INTO THE HOLIDAY WEEKEND.

&&

.NEAR TERM /THROUGH TODAY/...
UPDATE TO POPS AND TEMPS OTHERWISE NO CHANGES TO PREVIOUS
FORECAST.

A BROAD MID-LEVEL TROUGH ALONG WITH A SURFACE FRONTAL BOUNDARY
WILL MOVE SLOWLY ACROSS THE OHIO VALLEY OVERNIGHT. AN ISOLATED
SHOWER OR THUNDERSTORM CANNOT BE RULED OUT AHEAD OF THE FRONT
OVERNIGHT WITH WEAK ELEVATED INSTABILITY AND DEW POINTS NEAR 60.
NAM/LAMP SUPPORT THE DEVELOPMENT OF FOG IN LOCATIONS THAT RECEIVED
RAINFALL IN WESTERN PA, NORTHERN WV, AND WESTERN MD EARLIER THIS
EVENING. THUS, PATCHY FOG IS MENTIONED ACROSS THE LOWLANDS MOSTLY
WITH AREAS OF FOG ACROSS THE EASTERN RIDGES.

OVERNIGHT LOWS WILL REMAIN RELATIVELY WARM AS INCREASED BOUNDARY
LAYER MOISTURE WILL PRECLUDE A DRAMATIC DROP. TEMPERATURES ARE
FAIRLY CLOSE TO LAMP GUIDANCE OVERNIGHT, WITH LOWS IN RANGING FROM
THE MID 50S ACROSS THE EASTERN RIDGES TO THE LOWER 60S IN PORTIONS
OF EASTERN OHIO.

&&

.SHORT TERM /TONIGHT THROUGH THURSDAY/...
THE PROGRESS OF THE FRONT WILL BE SLOW GIVEN THE AFOREMENTIONED
WEAKNESS OF THE OVERALL WIND FIELD. WITH PERSISTENT UPPER/MID
LEVEL TROUGH FORECAST OVER THE EASTERN CONUS...EXPECT CONVECTIVE
TEMPERATURES TO REMAIN SUFFICIENTLY LOW FOR DIURNALLY SUPPORTED
SHOWER AND THUNDERSTORM DEVELOPMENT WITH FOCUS VIA THE
FRONT...RIDGES...OR OUTFLOW BOUNDARIES. WILL THUS FORECAST LIKELY
POPS ON TUESDAY WITH PASSAGE OF THE FRONT...FOLLOWED BY SCATTERED
PRECIP POTENTIAL THROUGH THE REMAINDER OF THE SHORT TERM.

WARM...HUMID CONDITIONS CAN BE EXPECTED TO CONTINUE THROUGH THE PERIOD.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
UPPER TROUGH MOVING OFF TO THE EAST WILL STILL SPAWN ISOLATED
SHOWERS/THUNDERSTORMS FRIDAY. AFTER THAT...UPPER RIDGE WILL BUILD
INTO THE REGION AND REMAIN NEARLY STATIONARY. ISOLATED
SHOWERS/THUNDERSTORMS CANNOT BE RULED OUT AS A WEAK SURFACE FRONT
TRIES TO MOVE THROUGH. TEMPERATURES SHOULD BE WELL ABOVE
NORMAL...WITH UPPER 80S AND LOWER 90S EXPECTED FOR THE HOLIDAY
WEEKEND.

&&

.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
SCATTERED EVENING SHOWERS HAVE SUBSIDED AND WILL CONTINUE TO
WEAKEN. ALL PORTS ESCAPED SIGNIFICANT RAIN THIS EVENING WHICH MAY
LIMIT FOG THREAT TOWARD DAYBREAK. HAVE USED JUST MVFR FOG LEVELS
FOR THE EARLY MORNING WITH GENERAL VFR CONDITIONS FOR TUESDAY. A
WEAK COLD FRONT WILL PUSH THROUGH THE DISTRICT BY TUESDAY
AFTERNOON...BRINGING A THREAT OF SHOWERS AND THUNDERSTORMS.

.OUTLOOK...TUESDAY NIGHT THROUGH SATURDAY...
SCATTERED SHOWERS ARE POSSIBLE THROUGH THURSDAY...WITH DIURNAL
CYCLE BRINGING GREATER COVERAGE DURING THE DAYTIME HOURS THAN
NIGHTTIME HOURS. AS THE FRONT STALLS EAST OF THE DISTRICT
TUESDAY EVENING... SURFACE DEW POINTS WILL REMAIN ELEVATED
AND WILL LIKELY RESULT IN MVFR VISIBILITY RESTRICTIONS IN FOG AT MOST
AIRPORT LOCATIONS DURING THE EARLY MORNING HOURS THROUGH THURSDAY.
COVERAGE OF SHOWERS SHOULD BE ISOLATED FOR FRIDAY AND SATURDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$

000
FXUS61 KPHI 220435
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1235 AM EDT TUE MAY 22 2012

.SYNOPSIS...
A LOW PRESSURE SYSTEM OFF THE MIDDLE ATLANTIC COAST IS FORECAST TO
DRIFT SLOWLY NORTHEAST AND REACH THE CANADIAN MARITIMES ON
WEDNESDAY. THEREAFTER AN ATLANTIC HIGH PRESSURE SYSTEM WILL BUILD
WEST AND PERSIST INTO THE START OF THE MEMORIAL DAY WEEKEND. A
BACKDOOR COLD FRONT FROM EASTERN CANADA IS THEN FORECAST TO APPROACH
AND STALL NEAR THE REGION ON SUNDAY AND MONDAY.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
UPDATED GRIDS INCLUDED INCREASED POPS ALONG NJ AND ERN PA WITH
SHOWERS ROTATING ACROSS THOSE AREAS ATTM. FEW OTHER CHANGES WERE
NEEDED. LOW PRESSURE WILL MOVE EAST OF THE AREA OVERNIGHT.
WINDS...WHICH ARE MOSTLY ERLY OR NERLY WILL SHIFT TO NRLY BY DAWN
IN MANY AREAS.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM WEDNESDAY/...
NOT MUCH CHANGE IN THE OVERALL TRENDS TOMORROW, EVEN THOUGH THE MDL
SOLNS AGAIN DIFFER ON HOW WET WE WILL BE.  THIS IS MAINLY DUE TO THE
FACT THAT ANY PRECIP WILL BE DEPENDENT ON THESE WAVES ON ELY FLOW
THAT HAVE BEEN DIFFICULT TO FORECAST MORE THAN A FEW HOURS IN
ADVANCE.  SO WHILE ALL MDLS FCST IT TO BE WARMER, THE MOST
OPTIMISTIC MDLS HAVE IT LESS DREARY AND THE MOST PESSIMISTIC...WELL
NOT SO MUCH...

ONCE AGAIN ANY PRECIP WAVES COULD PRODUCE LOCALLY HEAVY RAINFALL AS
THEY WILL BE SLOW MOVING, BUT OVERALL QPF WILL BE LIGHT.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/...
ITS GOING TO BE A SLOW RECOVERY FROM PRECIPITATION CHANCES AS THE
LONG TERM PROGRESSES WITH SOME UNSEASONABLY WARM WEATHER EXPECTED
OVER THE MEMORIAL DAY WEEKEND. THE LAZY FLOW ALOFT IS MORE TYPICAL
OF LATE AUGUST THAN LATE MAY AND AS SUCH THE SLOW MOVING CONVECTION
WILL PRODUCE SOME LOCALLY HEAVY DOWNPOURS. CONVECTION SHOULD BE
DIURNALLY DRIVEN AND THERE WILL BE A TRAIL OFF IN THE POPS AT
NIGHT.

SO BEGINNING WITH TUESDAY NIGHT CONVECTIVE COVERAGE AND CHANCES WILL
LOWER AS THE NIGHT PROGRESSES. WE DROP THE MENTION OF THUNDER AFTER
THE EVENING. FORECAST SOUNDINGS SUGGEST EITHER LOW CLOUDS AND OR FOG
WILL FORM. FOR NOW WE KEPT THE MENTION OF PATCHY FOG AS CONFIDENCE
ABOUT ONE OVER THE OTHER IS NOT HIGH ENOUGH TO MAKE A CHOICE OR CHANGE.
STAT GUIDANCE WAS CLOSE AND ACCEPTED.

THE CLOSED LOW ACROSS THE SERN CONUS IS FORECAST TO COME CLOSER ON
WEDNESDAY DAY. WITH CONVECTIVE TEMPS FORECAST TO BE IN THE MID 70S
WITH SOME DPVA AND OMEGA FORECAST ESPECIALLY SOUTHWEST. WE UPPED
THE POPS TO LIKELY BY LATE AFTERNOON PRETTY MUCH FROM THE LEHIGH
AND DELAWARE VALLEY SOUTHWESTWARD. MODELS ARE ALSO HINTING AND
SOME CONVERGENCE FROM DIFFERENT BAY BREEZES ON THE DELMARVA
PENINSULA. DIFFERENCES AS TO FORECAST INSTAB, BUT THE OVERALL WIND
FIELD IS FORECAST TO BE VERY WEAK AND NOT MUCH OF A DROP OFF OF
THETA E WITH HEIGHT IN THE MID LEVELS. SO MAIN CONCERN LOOKS LIKE
LOCALLY HEAVY RAIN. GIVEN THE FORECAST CONVECTIVE TEMPS, STAT
GUIDANCE LOOKS REASONABLE.

WE THROTTLE DOWN THE PRECIPITATION CHANCES AGAIN ON WEDNESDAY NIGHT.
ON THURSDAY A HIGH PRESSURE SYSTEM FROM JAMES BAY IS FORECAST TO
BUILD OVER THE NEW ENGLAND COASTAL WATERS. ITS TRACK IS A BIT
FARTHER TO THE EAST THAN SOME OF THE DIRTY HIGHS WE HAVE HAD THIS
SPRING. NEVERTHELESS IT GIVES US PAUSE AS TO HOW WARM A DAY THURSDAY
WILL BE AND HOW MANY LOW CLOUDS WILL COME IN OFF THE OCEAN. AS FAR
AS POPS GO, THINKING GFS EASTWARD EMPHASIS MAY BE GIVING THE HIGH
TOO LITTLE CREDIT, SO WE LEANED HIGHEST POPS FARTHER TO THE WEST.

THE 500MB TROF IS STILL LINGERING INTO THURSDAY NIGHT AND FRIDAY, SO
WE MAINTAIN SOME CHANCES. THE MARINE INFLUENCE ON FRIDAY BY THE
SURFACE HIGH APPEARS LESS, SO WE WENT ALONG WITH A COMPROMISE
BETWEEN GFS AND EURO MOS FOR MAX TEMPS.

THEN FOR MEMORIAL DAY WEEKEND PRETTY MUCH THE GIRL WITH THE CURL
TYPE WEEKEND IT SEEMS FOR US, EITHER VERY GOOD OR VERY BAD, SELDOM
IN THE MIDDLE. THIS TIME THE MODELS ARE CONTINUING TO OUTLOOK WHAT
WOULD BE A "SUMMER" TIME WEEKEND. THERE IS PRETTY MUCH GOOD
AGREEMENT ABOUT A WARM DAY FOR SATURDAY WITH RELATIVELY SPEAKING
OUR LOWEST CHANCES FOR PRECIPITATION. AFTER THAT THERE REMAINS
DIFFERENCES AS TO HOW MUCH CAN A BACKDOOR FRONT SLIP TOWARD OR
INTO OUR CWA ON SUNDAY OR MONDAY. THE GFS HAS BEEN MORE
AGGRESSIVE. THE 12Z EURO HAS TRENDED THE GFS`S WAY BUT MORE IN A
YOU WON THE BATTLE BUT NOT NECESSARILY THE TEMPERATURE WAR. WE
HAVE SOME SLIGHT CHANCES IN BECAUSE OF THE PROXIMITY TO THE FRONT.
FOR NOW WE ARE BANKING ON NOT MUCH OF A THERMAL EFFECT FROM THE
FRONT WITH MAX TEMPS PROGGED MUCH CLOSER TO EC MOS THAN GFS MOS.

&&

.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.

THE BREAK IN THE CLOUDS OVER DELAWARE AND NORTHEAST MARYLAND NOT
WITHSTANDING...MVFR AND IFR CONDITIONS WILL TRANSITION TO LIFR
CONDITIONS OVERNIGHT. THE QUESTION BECOMES JUST HOW QUICKLY.

PATCHY LIGHT RAIN AND DRIZZLE WILL CONTINUE ACROSS THE REGION DURING
THE NEXT FEW HOURS. THE LIGHT RAIN WILL HELP TO SATURATE THE LOW
LEVELS...AND AID THE TRANSITION TO LIFR. RIGHT NOW...IT WOULD APPEAR
TO ALL LOCATIONS WILL DROP TO LIFR BY 0400 UTC...AND STAY THERE
THROUGH AT LEAST 1300 UTC. THE STATISTICAL GUIDANCE SUGGESTS THAT
THE LOWER LEVELS COULD MOISTEN ENOUGH FOR 1/2SM IN FOG AT KACY AND
KMIV BETWEEN 0800 UTC AND 1300 UTC.

THE TRANSITION FROM LIFR THROUGH IFR TO MVFR SHOULD OCCUR BETWEEN
1300 UTC AND 1600 UTC...OCCURRING FIRST AT KRDG AND KABE...AND LAST
AT KACY. THE BOUNDARY LAYER COULD WARM ENOUGH FOR SOME LOCATIONS TO
REACH VFR FOR A TIME AT THE KPHL METRO AIRPORTS TUESDAY AFTERNOON.
BREAKS COULD ALLOW FOR SCATTERED THUNDERSTORMS...BUT THE CONFIDENCE
SIMPLY IS NOT THERE TO INCLUDE IN THE FORECAST YET.

OUTLOOK...
TUESDAY NIGHT THROUGH FRIDAY...MVFR OR IFR CONDS LATER EACH NIGHT
AND EARLY EACH DAY IN STRATUS OR FOG BECOMING VFR MIDDAY INTO THE
EVENING. LOCAL MVFR OR IFR CONDS IN SHOWERS OR TSTMS. OUTLOOKING
LESS COVERAGE AND DURATION OF IFR AND MVFR CONDITIONS ON FRIDAY.

SATURDAY...POSSIBLY SOME MVFR EARLY, OTHERWISE VFR.

&&

.MARINE...
SEAS HAVE BEEN SLOWLY CREEPING UP IN THE SOUTHEASTERLY
SWELL...ASSOCIATED WITH THE PERSISTENT ONSHORE FLOW. THE LATEST
WAVEWATCH GUIDANCE HAS SEAS REACHING SMALL CRAFT LEVELS AFTER
MIDNIGHT...SO THERE WAS NO APPRECIABLE CHANGE IN THE WAVE HEIGHT
FORECAST FOR THE OVERNIGHT.

A LOCAL ENHANCEMENT ON THE PRESSURE GRADIENT HAS RESULTED IN AN
INCREASE IN THE WIND SPEEDS ACROSS THE SOUTHERNMOST OCEAN WATERS
AND THE LOWER DELAWARE BAY. WINDS ARE STILL EXPECTED TO REMAIN
BELOW SMALL CRAFT LEVELS...BUT GUSTS TO 20 KNOTS IN THIS AREA IS
POSSIBLE THROUGH ABOUT 0600 UTC.

PERHAPS THE BIGGEST FORECAST ISSUE FOR THE OVERNIGHT WILL BE THE
FOG. SURFACE OBSERVATIONS ALONG THE COAST...AS WELL AS WEBCAMS
ALONG ANZ450-451 SHOW THE FOG IN PLACE...AND IT HAS BECOME DENSE
IN SPOTS. THE SHOWERS MOVING IN FROM THE SOUTHEAST COULD BE ENOUGH
TO KEEP VISIBILITIES FROM PLUMMETING OVERNIGHT. A MARINE WEATHER STATEMENT
WAS ISSUED TO HIGHLIGHT THE FOG THREAT IN THE ABOVEMENTIONED AREAS
OVERNIGHT.

FOR TUESDAY...WINDS ARE EXPECTED TO REMAIN BELOW SMALL CRAFT
LEVELS. HOWEVER...THE SOUTHEASTERLY SWELL SHOULD REMAIN AT OR
ABOVE 5 FEET ON THE OCEAN WATERS ALL TODAY INTO THE EVENING.

OUTLOOK...
WE ARE EXPECTING SMALL CRAFT ADVISORY CONDITIONS FROM SEAS TO
PERSIST INTO TUESDAY NIGHT. AFTER THAT WE ARE NOT OUTLOOKING SMALL
CRAFT ADVISORY CONDITIONS TO BE MET THROUGH THE REST OF THE
DETERMINISTIC FORECAST. THE ONSHORE GRADIENT AND SWELLS FROM THE
HIGH BUILDING ACROSS THE CANADIAN MARITIMES IS NOT EXPECTED TO BE
STRONG ENOUGH TO GENERATE SMALL CRAFT CONDITIONS CENTERED AROUND
THURSDAY. AFTER THAT THE HIGH BUILDS FARTHER INTO OUR MARINE AREA
REDUCING THE THREAT OF SMALL CRAFT CONDITIONS EVEN FURTHER. THE
APPROACHING BACK DOOR FRONT SHOULD NOT BE AN ISSUE, IF EVER AT ALL,
THROUGH SATURDAY.

&&

.HYDROLOGY...
IN THE LAST 24 HOURS...THERE ARE NUMEROUS REPORTS OF 1 TO 1.4
INCHES OF RAIN IN NE NJ. CONTD INFLOW IN THE MOST UNSTABLE CORRIDOR
OF MOISTURE TRANSPORT CONTINUES NOSED IN TOWD NE NJ AND W LI AND
WHILE THUNDER WONT OCCUR...POCKETS OF HEAVY RAIN ARE POSSIBLE.

IT LOOKS LIKE NORTHERN NEW JERSEY WILL BE THE LOCATION THAT SEES
THE MOST RAIN DURING THE OVERNIGHT. BASED ON THE LATEST MODEL
FORECASTS (WITH THE GFS DOING A MUCH BETTER JOB WITH THE PLACEMENT
OF THE RAIN THAN THE NAM THIS AFTERNOON)...AS MUCH AS AN INCH OF
RAIN COULD FALL BASINWIDE IN THIS AREA.

UPDATED FLASH FLOOD AND HEADWATER GUIDANCE SUGGESTS THAT 1 TO 2
INCHES OF RAIN WOULD NEED TO FALL IN NORTHERN NEW JERSEY BEFORE
PROBLEMS STARTED. THIS IS NOT EXPECTED OVERNIGHT.

SHOULD THE AXIS OF HEAVIEST OVERNIGHT RAIN COME IN FURTHER
SOUTHWEST...ANY SMALL STREAM FLOOD PROBLEMS WOULD MORE LIKELY
OCCUR IN EASTERN PENNSYLVANIA WHERE GRIDDED FLASH FLOOD GUIDANCE
SHOWS GREATER VULNERABILITY. 1 HR FFG NEAR 1.3 INCHES AND 6 TO 24
HR GUIDANCE IS CURRENTLY NEAR 1.9 INCHES.

&&

.RIP CURRENTS...
SWELL HEIGHTS NEAR 5 FEET...COMBINED WITH A DOMINANT 9 SECOND
PERIOD...WILL OUTWEIGH THE SLACKENING PRESSURE GRADIENT TUESDAY.
THE COMBINATION OF THE SWELL HEIGHT AND RELATIVELY LONG PERIOD
WILL RESULT IN A MODERATE RISK OF RIP CURRENTS TUESDAY. WHILE THE
COMBINATION SHOULD HAVE A LESSER EFFECT ON THE DELAWARE
BEACHES...IT WAS INCLUDED IN THE MODERATE RISK.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 AM EDT
     WEDNESDAY FOR ANZ450>455.

&&

$$
SYNOPSIS...GIGI
NEAR TERM...
SHORT TERM...NIERENBERG
LONG TERM...GIGI
AVIATION...GIGI/HAYES
MARINE...GIGI/NIERENBERG
HYDROLOGY...
RIP CURRENTS...

000
FXUS61 KCTP 220332
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1132 PM EDT MON MAY 21 2012

.SYNOPSIS...
AN UPPER LOW OVER THE SOUTHEAST COAST WILL OPEN UP AND LIFT
TONIGHT. A DEEPENING SHORTWAVE WILL SLOW DOWN AND CUT OFF OVR THE
CENTRAL APPALACHIANS DURING THE MIDDLE OF THE WEEK. PENNSYLVANIA
WILL BE ON THE EDGE OF THE REBUILDING UPPER RIDGE ACROSS THE OHIO
VALLEY BY THE END OF WEEK. THIS BUILDING RIDGE WILL KEEP WARM
TEMPERATURES ACROSS THE REGION INTO THE HOLIDAY WEEKEND.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
 A CIRCULATION AROUND A BROAD UPPER LOW OVER THE SOUTHEASTERN
UNITED STATES AND WESTERN ATLANTIC AND SFC HIGH TO THE EAST OF NEW
ENGLAND CONTINUES TO DIRECT HIGHER PW AIR INTO SOUTHEAST AND
CENTRAL PA COINCIDING WITH MARITIME EASTERLY FLOW PROGRESSING WNW
INTO THE ALLEGHENIES. THIS CONVERGENCE OF UPPER LEVEL SOUTHEAST
MOIST FLOW CONTINUES TO BRING STEADY PRECIPITATION THROUGH
CENTRAL PA OVERNIGHT...AND INTO TUESDAY MORNING. THE BAND OF
PRECIPITATION WILL SLOWLY MOVE NORTHWARD...WITH STEADY...BUT ONLY
BRIEF PERIODS OF HEAVY PRECIPITATION. NOT EXPECTING ANY FLOODING
AS THE REGION IT IS OVER IS PREDOMINANTLY NOT PRONE TO ANY FLASHY
BASINS. THE PRECIP IS MOVING SLOWLY...BUT A LIGHT ENOUGH INTENSITY
WHERE FLOODING ISNT A THREAT. HOWEVER WILL CONTINUE TO KEEP AN EYE
ON THINGS...AS IT HAS BEEN WET THE LAST 2 WEEKS. EXPECTING THE
PRECIP TO FADE TOWARDS SUNRISE AS THE CONVERGENCE SHIFTS
EASTWARD...AND THE UPPER LEVEL WAVE PROPAGATING EASTWARD BRINGS A
BROADER SWATH OF MOISTURE THROUGH PA.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/...
A GENERAL DECREASE IN SHOWER ACTIVITY IS EXPECTED LATE AS UPPER
LOW OPENS UP AND LIFTS NE. BIGGER STORY EARLY TUESDAY MORNING COULD BE
AREAS OF POTENTIALLY DENSE FOG. PLENTY OF LL MOISTURE AND A NEARLY
CALM WIND WILL BE FAVORABLE FOR FOG.

AS E COAST UPPER LOW OPENS UP AND LIFTS INTO THE CANADIAN
MARITIMES...UPSTREAM SHORTWAVE WILL DEEPEN AND CUTOFF OVR THE
TN VALLEY ON TUESDAY. LG SCALE FORCING AHEAD OF THIS FEATURE WILL
PRODUCE MORE SHRA/TSRA...MAINLY DURING THE AFT...AS SOME HEATING
TAKES PLACE...AND TEMPS WARM INTO THE 70S. GEFS/SREF DATA BOTH
SUGGEST BEST CHC OF SHRA/TSRA WILL BE ALONG THE SPINE OF THE
APPALACHIANS. OVERCAST SKIES AND VERY LGT WINDS ALOFT SUGGEST
THERE WILL BE VERY LITTLE THREAT OF SVR WX. BLEND OF GEFS/SREF
QPF RANGES FROM 0.2 TO 0.3 INCHES TONIGHT AND TUESDAY.

&&

.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
STILL SOME CHC OF A SHOWER OR THUNDERSTORM WED INTO FRIDAY...
MAINLY ACROSS THE SE DURING THE AFTERNOON AND PERHAPS EARLY
EVENING HOURS...AS THE REMAINS OF THE UPPER LVL LOW REMAIN
NEARBY.

GFS AND OTHERS MORE IN LINE WITH KEEPING FRONT NORTH OF OUR
AREA THIS COMING HOLIDAY WEEKEND...GFS WAS TOO COLD AND TOO
FAR SOUTH YESTERDAY WITH THINGS. EC HAS BEEN HINTING AT A
LARGE RIDGE BUILDING EASTWARD WITH TIME...AND VERY WARM
TEMPS. LEFT FCST DRY AFTER SAT...AS IF FRONT MAKES INTO
N PA...IT WOULD HAVE VERY LITTLE SUPPORT AND NOT MUCH MORE
THAN A WIND SHIFT LINE.

&&

.AVIATION /03Z TUESDAY THROUGH SATURDAY/...
SEMI-PERSISTENT AXIS OF RAIN CONTINUES TO STREAM FROM SOUTH TO
NORTH ACROSS CENTRAL PENNSYLVANIA. VFR CONDITIONS AT KBFD AND
KLNS WILL BE SHORT LIVED AS FOG WILL LIKELY DEVELOP IN THESE AREAS
OVER THE NEXT FEW HOURS. CLOSER TO THE AXIS OF RAIN...CONDITIONS
RANGE FROM MVFR TO LIFR...WITH CIGS 300 TO 700 FT AT KAOO AND KUNV
RESPECTIVELY. OVERALL...CONDITIONS TO FLUCTUATE FROM MVFR TO IFR
OVERNIGHT...WITH LOWEST CONDITIONS IN THE VICINITY OF PERSISTENT
RAIN.

SOME DIURNAL IMPROVEMENT IN CONDITIONS POSSIBLE TUESDAY AFTERNOON
AS UPPER FLOW BECOMES A BIT MORE SOUTHERLY IN ADVANCE OF NEWLY
DEVELOPING TN VALLEY UPPER LEVEL LOW. WITH THE POTENTIAL INCREASE
IN CIGS AND VSBYS WILL BE INCREASING CHANCES OF SHOWERS AND
POSSIBLE TSRA.

OUTLOOK...
WED...WIDESPREAD MVFR/IFR CIGS AND VSBYS LIKELY IN SHRA AND SCT
TSRA.
THU...PRIMARILY VFR. SCT SHRA/TSRA POSS MAINLY SE.
FRI...PRIMARILY VFR. ISOLD SHRA/TSRA POSS MAINLY SE.
SAT...VFR. A CHC OF A SHRA OR TSRA ACROSS THE NORTH.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...DEVOIR/MARTIN
NEAR TERM...CERU/MARTIN
SHORT TERM...DEVOIR/FITZGERALD/MARTIN
LONG TERM...MARTIN
AVIATION...JUNG

000
FXUS61 KCTP 220257
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1057 PM EDT MON MAY 21 2012

.SYNOPSIS...
AN UPPER LOW OVER THE SOUTHEAST COAST WILL OPEN UP AND LIFT
TONIGHT. A DEEPENING SHORTWAVE WILL SLOW DOWN AND CUT OFF OVR THE
CENTRAL APPALACHIANS DURING THE MIDDLE OF THE WEEK. PENNSYLVANIA
WILL BE ON THE EDGE OF THE REBUILDING UPPER RIDGE ACROSS THE OHIO
VALLEY BY THE END OF WEEK. THIS BUILDING RIDGE WILL KEEP WARM
TEMPERATURES ACROSS THE REGION INTO THE HOLIDAY WEEKEND.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
UPPER LOW OVER THE CAROLINA COAST WILL LIFT NORTH ALONG THE E
COAST DURING THE NEXT 24HRS. MOIST...EASTERLY LL JET AND UPPER
LVL DIVERGENCE PRECEDING THE UPPER LOW WILL BRING SHOWERS TO MOST
OF CENTRAL PA THROUGH TONIGHT. MAIN BAND OF SHOWERS WILL MOVE
THROUGH THE CENTER OF THE STATE OVERNIGHT. THE CIRCULATION AROUND
A BROAD UPPER LOW OVER THE SOUTHEASTERN UNITED STATES AND WESTERN
ATLANTIC AND SFC HIGH TO THE EAST OF NEW ENGLAND IS DIRECTING
HIGHER PW AIR INTO SOUTHEAST AND CENTRAL PA COINCIDING WITH
MARITIME EASTERLY FLOW PROGRESSING WNW INTO THE ALLEGHENIES. THE
PRECIP IS MOVING SLOWLY...BUT A LIGHT ENOUGH INTENSITY WHERE
FLOODING ISNT A THREAT. HOWEVER WILL CONTINUE TO KEEP AN EYE ON
THINGS...AS IT HAS BEEN WET THE LAST 2 WEEKS.

PRECIP WILL CONTINUE OVERNIGHT BUT FADE INTO TOMORROW
MORNING...WITH PRECIP ENDING FROM THIS BAND.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/...
A GENERAL DECREASE IN SHOWER ACTIVITY IS EXPECTED LATE AS UPPER
LOW OPENS UP AND LIFTS NE. BIGGER STORY EARLY TUESDAY MORNING COULD BE
AREAS OF POTENTIALLY DENSE FOG. PLENTY OF LL MOISTURE AND A NEARLY
CALM WIND WILL BE FAVORABLE FOR FOG.

AS E COAST UPPER LOW OPENS UP AND LIFTS INTO THE CANADIAN
MARITIMES...UPSTREAM SHORTWAVE WILL DEEPEN AND CUTOFF OVR THE
TN VALLEY ON TUESDAY. LG SCALE FORCING AHEAD OF THIS FEATURE WILL
PRODUCE MORE SHRA/TSRA...MAINLY DURING THE AFT...AS SOME HEATING
TAKES PLACE...AND TEMPS WARM INTO THE 70S. GEFS/SREF DATA BOTH
SUGGEST BEST CHC OF SHRA/TSRA WILL BE ALONG THE SPINE OF THE
APPALACHIANS. OVERCAST SKIES AND VERY LGT WINDS ALOFT SUGGEST
THERE WILL BE VERY LITTLE THREAT OF SVR WX. BLEND OF GEFS/SREF
QPF RANGES FROM 0.2 TO 0.3 INCHES TONIGHT AND TUESDAY.

&&

.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
STILL SOME CHC OF A SHOWER OR THUNDERSTORM WED INTO FRIDAY...
MAINLY ACROSS THE SE DURING THE AFTERNOON AND PERHAPS EARLY
EVENING HOURS...AS THE REMAINS OF THE UPPER LVL LOW REMAIN
NEARBY.

GFS AND OTHERS MORE IN LINE WITH KEEPING FRONT NORTH OF OUR
AREA THIS COMING HOLIDAY WEEKEND...GFS WAS TOO COLD AND TOO
FAR SOUTH YESTERDAY WITH THINGS. EC HAS BEEN HINTING AT A
LARGE RIDGE BUILDING EASTWARD WITH TIME...AND VERY WARM
TEMPS. LEFT FCST DRY AFTER SAT...AS IF FRONT MAKES INTO
N PA...IT WOULD HAVE VERY LITTLE SUPPORT AND NOT MUCH MORE
THAN A WIND SHIFT LINE.

&&

.AVIATION /03Z TUESDAY THROUGH SATURDAY/...
SEMI-PERSISTENT AXIS OF RAIN CONTINUES TO STREAM FROM SOUTH TO
NORTH ACROSS CENTRAL PENNSYLVANIA. VFR CONDITIONS AT KBFD AND
KLNS WILL BE SHORT LIVED AS FOG WILL LIKELY DEVELOP IN THESE AREAS
OVER THE NEXT FEW HOURS. CLOSER TO THE AXIS OF RAIN...CONDITIONS
RANGE FROM MVFR TO LIFR...WITH CIGS 300 TO 700 FT AT KAOO AND KUNV
RESPECTIVELY. OVERALL...CONDITIONS TO FLUCTUATE FROM MVFR TO IFR
OVERNIGHT...WITH LOWEST CONDITIONS IN THE VICINITY OF PERSISTENT
RAIN.

SOME DIURNAL IMPROVEMENT IN CONDITIONS POSSIBLE TUESDAY AFTERNOON
AS UPPER FLOW BECOMES A BIT MORE SOUTHERLY IN ADVANCE OF NEWLY
DEVELOPING TN VALLEY UPPER LEVEL LOW. WITH THE POTENTIAL INCREASE
IN CIGS AND VSBYS WILL BE INCREASING CHANCES OF SHOWERS AND
POSSIBLE TSRA.

OUTLOOK...
WED...WIDESPREAD MVFR/IFR CIGS AND VSBYS LIKELY IN SHRA AND SCT
TSRA.
THU...PRIMARILY VFR. SCT SHRA/TSRA POSS MAINLY SE.
FRI...PRIMARILY VFR. ISOLD SHRA/TSRA POSS MAINLY SE.
SAT...VFR. A CHC OF A SHRA OR TSRA ACROSS THE NORTH.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...DEVOIR/MARTIN
NEAR TERM...CERU/MARTIN
SHORT TERM...DEVOIR/FITZGERALD/MARTIN
LONG TERM...MARTIN
AVIATION...JUNG

000
FXUS61 KPBZ 220243
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
1043 PM EDT MON MAY 21 2012

.SYNOPSIS...
A FRONTAL BOUNDARY WILL SLOWLY MOVE ACROSS THE AREA OVERNIGHT INTO
TUESDAY. SHOWERS AND THUNDERSTORMS WILL RE-DEVELOP ALONG AND AHEAD
OF THE FRONT TUESDAY AFTERNOON AND CONTINUE INTO TUESDAY NIGHT.
WARM WEATHER CAN BE EXPECTED TO CONTINUE WITH HUMIDITY INCREASING
LATE THIS WEEK INTO THE HOLIDAY WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
AN ENHANCED SHORT TERM FORECAST UPDATE HAS BEEN ISSUED IN ORDER TO
REDUCE POPS TO SCHC OVERNIGHT AND TO ADD THE MENTION OF FOG.

A BROAD MID-LEVEL TROUGH ALONG WITH A SURFACE FRONTAL BOUNDARY
WILL MOVE SLOWLY ACROSS THE OHIO VALLEY OVERNIGHT. AN ISOLATED
SHOWER OR THUNDERSTORM CANNOT BE RULED OUT AHEAD OF THE FRONT
OVERNIGHT WITH WEAK ELEVATED INSTABILITY AND DEW POINTS NEAR 60.
NAM/LAMP SUPPORT THE DEVELOPMENT OF FOG IN LOCATIONS THAT RECEIVED
RAINFALL IN WESTERN PA, NORTHERN WV, AND WESTERN MD EARLIER THIS
EVENING. THUS, PATCHY FOG IS MENTIONED ACROSS THE LOWLANDS MOSTLY
WITH AREAS OF FOG ACROSS THE EASTERN RIDGES.

OVERNIGHT LOWS WILL REMAIN RELATIVELY WARM AS INCREASED BOUNDARY
LAYER MOISTURE WILL PRECLUDE A DRAMATIC DROP. TEMPERATURES ARE
FAIRLY CLOSE TO LAMP GUIDANCE OVERNIGHT, WITH LOWS IN RANGING FROM
THE MID 50S ACROSS THE EASTERN RIDGES TO THE LOWER 60S IN PORTIONS
OF EASTERN OHIO.

&&

.SHORT TERM /TUESDAY THROUGH THURSDAY/...
THE PROGRESS OF THE FRONT WILL BE SLOW GIVEN THE AFOREMENTIONED
WEAKNESS OF THE OVERALL WIND FIELD. WITH PERSISTENT UPPER/MID
LEVEL TROUGH FORECAST OVER THE EASTERN CONUS...EXPECT CONVECTIVE
TEMPERATURES TO REMAIN SUFFICIENTLY LOW FOR DIURNALLY SUPPORTED
SHOWER AND THUNDERSTORM DEVELOPMENT WITH FOCUS VIA THE
FRONT...RIDGES...OR OUTFLOW BOUNDARIES. WILL THUS FORECAST LIKELY
POPS ON TUESDAY WITH PASSAGE OF THE FRONT...FOLLOWED BY SCATTERED
PRECIP POTENTIAL THROUGH THE REMAINDER OF THE SHORT TERM.

WARM...HUMID CONDITIONS CAN BE EXPECTED TO CONTINUE THROUGH THE PERIOD.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
UPPER TROUGH MOVING OFF TO THE EAST WILL STILL SPAWN ISOLATED
SHOWERS/THUNDERSTORMS FRIDAY. AFTER THAT...UPPER RIDGE WILL BUILD
INTO THE REGION AND REMAIN NEARLY STATIONARY. ISOLATED
SHOWERS/THUNDERSTORMS CANNOT BE RULED OUT AS A WEAK SURFACE FRONT
TRIES TO MOVE THROUGH. TEMPERATURES SHOULD BE WELL ABOVE
NORMAL...WITH UPPER 80S AND LOWER 90S EXPECTED FOR THE HOLIDAY
WEEKEND.

&&

.AVIATION /02Z TUESDAY THROUGH SATURDAY/...
SCATTERED EVENING SHOWERS HAVE SUBSIDED AND WILL CONTINUE TO
WEAKEN. ALL PORTS ESCAPED SIGNIFICANT RAIN THIS EVENING WHICH MAY
LIMIT FOG THREAT TOWARD DAYBREAK. HAVE USED JUST MVFR FOG LEVELS
FOR THE EARLY MORNING WITH GENERAL VFR CONDITIONS FOR TUESDAY. A
WEAK COLD FRONT WILL PUSH THROUGH THE DISTRICT BY TUESDAY
AFTERNOON...BRINGING A THREAT OF SHOWERS AND THUNDERSTORMS.

.OUTLOOK...TUESDAY NIGHT THROUGH SATURDAY...
SCATTERED SHOWERS ARE POSSIBLE THROUGH THURSDAY...WITH DIURNAL
CYCLE BRINGING GREATER COVERAGE DURING THE DAYTIME HOURS THAN
NIGHTTIME HOURS. AS THE FRONT STALLS EAST OF THE DISTRICT
TUESDAY EVENING... SURFACE DEW POINTS WILL REMAIN ELEVATED
AND WILL LIKELY RESULT IN MVFR VISIBILITY RESTRICTIONS IN FOG AT MOST
AIRPORT LOCATIONS DURING THE EARLY MORNING HOURS THROUGH THURSDAY.
COVERAGE OF SHOWERS SHOULD BE ISOLATED FOR FRIDAY AND SATURDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$

000
FXUS61 KPHI 220234
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1034 PM EDT MON MAY 21 2012

.SYNOPSIS...
A LOW PRESSURE SYSTEM OFF THE MIDDLE ATLANTIC COAST IS FORECAST TO
DRIFT SLOWLY NORTHEAST AND REACH THE CANADIAN MARITIMES ON
WEDNESDAY. THEREAFTER AN ATLANTIC HIGH PRESSURE SYSTEM WILL BUILD
WEST AND PERSIST INTO THE START OF THE MEMORIAL DAY WEEKEND. A
BACKDOOR COLD FRONT FROM EASTERN CANADA IS THEN FORECAST TO APPROACH
AND STALL NEAR THE REGION ON SUNDAY AND MONDAY.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
THE MAIN FORECAST PROBLEM FOR THE OVERNIGHT WILL BE THE COVERAGE OF
SHOWERS...ESPECIALLY ACROSS EASTERN SECTIONS.

THE AREA OF SHOWERS THAT HAS LURKED IN THE AREA OF HIGHER PRECIPITABLE
WATER WANED EARLIER THIS EVENING...BUT HAS COME BACK INT HE PAST
90 MINUTES. THE IR IMAGES IN THE AREA EAST OF SOUTHEAST VIRGINIA
HAVE SHOWN WARMING TOPS FOR THE MOST PART. BASED ON EXTRAPOLATION
OF THE AREA OF HEAVIEST RAIN NOW EAST OF THE SOUTHERN DELAWARE
COAST...PARTS OF NORTHERN NEW JERSEY LOOK TO SEE THE HEAVIEST RAIN
OVERNIGHT. BASIN AVERAGE OF 0.75 INCHES LOOKS ABOUT RIGHT...AND
THIS MUCH ADDITIONAL RAIN SHOULD NOW RESULT IN MUCH MORE THAN
NUISANCE FLOODING.

THE NEXT FORECAST PROBLEM IS THE FOG. THE AREA OF FOG OVER
MONMOUTH AND OCEAN COUNTIES DOES NOT APPEAR TO HAVE GROWN MUCH IN
THE PAST 90 MINUTES. SURFACE OBSERVATIONS AND WEBCAMS IN THE AREA
SUGGEST THAT THE FOG IS DENSE IN SPOTS...BUT NOT ENOUGH COVERAGE
YET FOR A DENSE FOG ADVISORY. THE FOG WAS HIGHLIGHTED IN THE
LATEST FORECAST UPDATE...AND THE SPECIAL WEATHER STATEMENT WILL BE
UPDATED TO DRAW MORE ATTENTION TO IT.

NOT MUCH CHANGE IN THE TEMPERATURE AND WIND FORECASTS FOR THE
OVERNIGHT FROM THE PREVIOUS FORECAST.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/...
NOT MUCH CHANGE IN THE OVERALL TRENDS TOMORROW, EVEN THOUGH THE MDL
SOLNS AGAIN DIFFER ON HOW WET WE WILL BE.  THIS IS MAINLY DUE TO THE
FACT THAT ANY PRECIP WILL BE DEPENDENT ON THESE WAVES ON ELY FLOW
THAT HAVE BEEN DIFFICULT TO FORECAST MORE THAN A FEW HOURS IN
ADVANCE.  SO WHILE ALL MDLS FCST IT TO BE WARMER, THE MOST
OPTIMISTIC MDLS HAVE IT LESS DREARY AND THE MOST PESSIMISTIC...WELL
NOT SO MUCH...

ONCE AGAIN ANY PRECIP WAVES COULD PRODUCE LOCALLY HEAVY RAINFALL AS
THEY WILL BE SLOW MOVING, BUT OVERALL QPF WILL BE LIGHT.

&&

.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
ITS GOING TO BE A SLOW RECOVERY FROM PRECIPITATION CHANCES AS THE
LONG TERM PROGRESSES WITH SOME UNSEASONABLY WARM WEATHER EXPECTED
OVER THE MEMORIAL DAY WEEKEND. THE LAZY FLOW ALOFT IS MORE TYPICAL
OF LATE AUGUST THAN LATE MAY AND AS SUCH THE SLOW MOVING CONVECTION
WILL PRODUCE SOME LOCALLY HEAVY DOWNPOURS. CONVECTION SHOULD BE
DIURNALLY DRIVEN AND THERE WILL BE A TRAIL OFF IN THE POPS AT
NIGHT.

SO BEGINNING WITH TUESDAY NIGHT CONVECTIVE COVERAGE AND CHANCES WILL
LOWER AS THE NIGHT PROGRESSES. WE DROP THE MENTION OF THUNDER AFTER
THE EVENING. FORECAST SOUNDINGS SUGGEST EITHER LOW CLOUDS AND OR FOG
WILL FORM. FOR NOW WE KEPT THE MENTION OF PATCHY FOG AS CONFIDENCE
ABOUT ONE OVER THE OTHER IS NOT HIGH ENOUGH TO MAKE A CHOICE OR CHANGE.
STAT GUIDANCE WAS CLOSE AND ACCEPTED.

THE CLOSED LOW ACROSS THE SERN CONUS IS FORECAST TO COME CLOSER ON
WEDNESDAY DAY. WITH CONVECTIVE TEMPS FORECAST TO BE IN THE MID 70S
WITH SOME DPVA AND OMEGA FORECAST ESPECIALLY SOUTHWEST. WE UPPED
THE POPS TO LIKELY BY LATE AFTERNOON PRETTY MUCH FROM THE LEHIGH
AND DELAWARE VALLEY SOUTHWESTWARD. MODELS ARE ALSO HINTING AND
SOME CONVERGENCE FROM DIFFERENT BAY BREEZES ON THE DELMARVA
PENINSULA. DIFFERENCES AS TO FORECAST INSTAB, BUT THE OVERALL WIND
FIELD IS FORECAST TO BE VERY WEAK AND NOT MUCH OF A DROP OFF OF
THETA E WITH HEIGHT IN THE MID LEVELS. SO MAIN CONCERN LOOKS LIKE
LOCALLY HEAVY RAIN. GIVEN THE FORECAST CONVECTIVE TEMPS, STAT
GUIDANCE LOOKS REASONABLE.

WE THROTTLE DOWN THE PRECIPITATION CHANCES AGAIN ON WEDNESDAY NIGHT.
ON THURSDAY A HIGH PRESSURE SYSTEM FROM JAMES BAY IS FORECAST TO
BUILD OVER THE NEW ENGLAND COASTAL WATERS. ITS TRACK IS A BIT
FARTHER TO THE EAST THAN SOME OF THE DIRTY HIGHS WE HAVE HAD THIS
SPRING. NEVERTHELESS IT GIVES US PAUSE AS TO HOW WARM A DAY THURSDAY
WILL BE AND HOW MANY LOW CLOUDS WILL COME IN OFF THE OCEAN. AS FAR
AS POPS GO, THINKING GFS EASTWARD EMPHASIS MAY BE GIVING THE HIGH
TOO LITTLE CREDIT, SO WE LEANED HIGHEST POPS FARTHER TO THE WEST.

THE 500MB TROF IS STILL LINGERING INTO THURSDAY NIGHT AND FRIDAY, SO
WE MAINTAIN SOME CHANCES. THE MARINE INFLUENCE ON FRIDAY BY THE
SURFACE HIGH APPEARS LESS, SO WE WENT ALONG WITH A COMPROMISE
BETWEEN GFS AND EURO MOS FOR MAX TEMPS.

THEN FOR MEMORIAL DAY WEEKEND PRETTY MUCH THE GIRL WITH THE CURL
TYPE WEEKEND IT SEEMS FOR US, EITHER VERY GOOD OR VERY BAD, SELDOM
IN THE MIDDLE. THIS TIME THE MODELS ARE CONTINUING TO OUTLOOK WHAT
WOULD BE A "SUMMER" TIME WEEKEND. THERE IS PRETTY MUCH GOOD
AGREEMENT ABOUT A WARM DAY FOR SATURDAY WITH RELATIVELY SPEAKING
OUR LOWEST CHANCES FOR PRECIPITATION. AFTER THAT THERE REMAINS
DIFFERENCES AS TO HOW MUCH CAN A BACKDOOR FRONT SLIP TOWARD OR
INTO OUR CWA ON SUNDAY OR MONDAY. THE GFS HAS BEEN MORE
AGGRESSIVE. THE 12Z EURO HAS TRENDED THE GFS`S WAY BUT MORE IN A
YOU WON THE BATTLE BUT NOT NECESSARILY THE TEMPERATURE WAR. WE
HAVE SOME SLIGHT CHANCES IN BECAUSE OF THE PROXIMITY TO THE FRONT.
FOR NOW WE ARE BANKING ON NOT MUCH OF A THERMAL EFFECT FROM THE
FRONT WITH MAX TEMPS PROGGED MUCH CLOSER TO EC MOS THAN GFS MOS.

&&

.AVIATION /03Z TUESDAY THROUGH SATURDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.

THE BREAK IN THE CLOUDS OVER DELAWARE AND NORTHEAST MARYLAND NOT
WITHSTANDING...MVFR AND IFR CONDITIONS WILL TRANSITION TO LIFR
CONDITIONS OVERNIGHT. THE QUESTION BECOMES JUST HOW QUICKLY.

PATCHY LIGHT RAIN AND DRIZZLE WILL CONTINUE ACROSS THE REGION DURING
THE NEXT FEW HOURS. THE LIGHT RAIN WILL HELP TO SATURATE THE LOW
LEVELS...AND AID THE TRANSITION TO LIFR. RIGHT NOW...IT WOULD APPEAR
TO ALL LOCATIONS WILL DROP TO LIFR BY 0400 UTC...AND STAY THERE
THROUGH AT LEAST 1300 UTC. THE STATISTICAL GUIDANCE SUGGESTS THAT
THE LOWER LEVELS COULD MOISTEN ENOUGH FOR 1/2SM IN FOG AT KACY AND
KMIV BETWEEN 0800 UTC AND 1300 UTC.

THE TRANSITION FROM LIFR THROUGH IFR TO MVFR SHOULD OCCUR BETWEEN
1300 UTC AND 1600 UTC...OCCURRING FIRST AT KRDG AND KABE...AND LAST
AT KACY. THE BOUNDARY LAYER COULD WARM ENOUGH FOR SOME LOCATIONS TO
REACH VFR FOR A TIME AT THE KPHL METRO AIRPORTS TUESDAY AFTERNOON.
BREAKS COULD ALLOW FOR SCATTERED THUNDERSTORMS...BUT THE CONFIDENCE
SIMPLY IS NOT THERE TO INCLUDE IN THE FORECAST YET.

OUTLOOK...
TUESDAY NIGHT THROUGH FRIDAY...MVFR OR IFR CONDS LATER EACH NIGHT
AND EARLY EACH DAY IN STRATUS OR FOG BECOMING VFR MIDDAY INTO THE
EVENING. LOCAL MVFR OR IFR CONDS IN SHOWERS OR TSTMS. OUTLOOKING
LESS COVERAGE AND DURATION OF IFR AND MVFR CONDITIONS ON FRIDAY.

SATURDAY...POSSIBLY SOME MVFR EARLY, OTHERWISE VFR.

&&

.MARINE...
SEAS HAVE BEEN SLOWLY CREEPING UP IN THE SOUTHEASTERLY
SWELL...ASSOCIATED WITH THE PERSISTENT ONSHORE FLOW. THE LATEST
WAVEWATCH GUIDANCE HAS SEAS REACHING SMALL CRAFT LEVELS AFTER
MIDNIGHT...SO THERE WAS NO APPRECIABLE CHANGE IN THE WAVE HEIGHT
FORECAST FOR THE OVERNIGHT.

A LOCAL ENHANCEMENT ON THE PRESSURE GRADIENT HAS RESULTED IN AN
INCREASE IN THE WIND SPEEDS ACROSS THE SOUTHERNMOST OCEAN WATERS
AND THE LOWER DELAWARE BAY. WINDS ARE STILL EXPECTED TO REMAIN
BELOW SMALL CRAFT LEVELS...BUT GUSTS TO 20 KNOTS IN THIS AREA IS
POSSIBLE THROUGH ABOUT 0600 UTC.

PERHAPS THE BIGGEST FORECAST ISSUE FOR THE OVERNIGHT WILL BE THE
FOG. SURFACE OBSERVATIONS ALONG THE COAST...AS WELL AS WEBCAMS
ALONG ANZ450-451 SHOW THE FOG IN PLACE...AND IT HAS BECOME DENSE
IN SPOTS. THE SHOWERS MOVING IN FROM THE SOUTHEAST COULD BE ENOUGH
TO KEEP VISIBILITIES FROM PLUMMETING OVERNIGHT. A MARINE WEATHER STATEMENT
WAS ISSUED TO HIGHLIGHT THE FOG THREAT IN THE ABOVEMENTIONED AREAS
OVERNIGHT.

FOR TUESDAY...WINDS ARE EXPECTED TO REMAIN BELOW SMALL CRAFT
LEVELS. HOWEVER...THE SOUTHEASTERLY SWELL SHOULD REMAIN AT OR
ABOVE 5 FEET ON THE OCEAN WATERS ALL TODAY INTO THE EVENING.

OUTLOOK...
WE ARE EXPECTING SMALL CRAFT ADVISORY CONDITIONS FROM SEAS TO
PERSIST INTO TUESDAY NIGHT. AFTER THAT WE ARE NOT OUTLOOKING SMALL
CRAFT ADVISORY CONDITIONS TO BE MET THROUGH THE REST OF THE
DETERMINISTIC FORECAST. THE ONSHORE GRADIENT AND SWELLS FROM THE
HIGH BUILDING ACROSS THE CANADIAN MARITIMES IS NOT EXPECTED TO BE
STRONG ENOUGH TO GENERATE SMALL CRAFT CONDITIONS CENTERED AROUND
THURSDAY. AFTER THAT THE HIGH BUILDS FARTHER INTO OUR MARINE AREA
REDUCING THE THREAT OF SMALL CRAFT CONDITIONS EVEN FURTHER. THE
APPROACHING BACK DOOR FRONT SHOULD NOT BE AN ISSUE, IF EVER AT ALL,
THROUGH SATURDAY.

&&

.HYDROLOGY...
IN THE LAST 24 HOURS...THERE ARE NUMEROUS REPORTS OF 1 TO 1.4
INCHES OF RAIN IN NE NJ. CONTD INFLOW IN THE MOST UNSTABLE CORRIDOR
OF MOISTURE TRANSPORT CONTINUES NOSED IN TOWD NE NJ AND W LI AND
WHILE THUNDER WONT OCCUR...POCKETS OF HEAVY RAIN ARE POSSIBLE.

IT LOOKS LIKE NORTHERN NEW JERSEY WILL BE THE LOCATION THAT SEES
THE MOST RAIN DURING THE OVERNIGHT. BASED ON THE LATEST MODEL
FORECASTS (WITH THE GFS DOING A MUCH BETTER JOB WITH THE PLACEMENT
OF THE RAIN THAN THE NAM THIS AFTERNOON)...AS MUCH AS AN INCH OF
RAIN COULD FALL BASINWIDE IN THIS AREA.

UPDATED FLASH FLOOD AND HEADWATER GUIDANCE SUGGESTS THAT 1 TO 2
INCHES OF RAIN WOULD NEED TO FALL IN NORTHERN NEW JERSEY BEFORE
PROBLEMS STARTED. THIS IS NOT EXPECTED OVERNIGHT.

SHOULD THE AXIS OF HEAVIEST OVERNIGHT RAIN COME IN FURTHER
SOUTHWEST...ANY SMALL STREAM FLOOD PROBLEMS WOULD MORE LIKELY
OCCUR IN EASTERN PENNSYLVANIA WHERE GRIDDED FLASH FLOOD GUIDANCE
SHOWS GREATER VULNERABILITY. 1 HR FFG NEAR 1.3 INCHES AND 6 TO 24
HR GUIDANCE IS CURRENTLY NEAR 1.9 INCHES.

&&

.RIP CURRENTS...
SWELL HEIGHTS NEAR 5 FEET...COMBINED WITH A DOMINANT 9 SECOND
PERIOD...WILL OUTWEIGH THE SLACKENING PRESSURE GRADIENT TUESDAY.
THE COMBINATION OF THE SWELL HEIGHT AND RELATIVELY LONG PERIOD
WILL RESULT IN A MODERATE RISK OF RIP CURRENTS TUESDAY. WHILE THE
COMBINATION SHOULD HAVE A LESSER EFFECT ON THE DELAWARE
BEACHES...IT WAS INCLUDED IN THE MODERATE RISK.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 AM EDT
     WEDNESDAY FOR ANZ450>455.

&&

$$
SYNOPSIS...GIGI
NEAR TERM...HAYES
SHORT TERM...NIERENBERG
LONG TERM...GIGI
AVIATION...GIGI/HAYES
MARINE...GIGI/NIERENBERG
HYDROLOGY...1034P
RIP CURRENTS...

000
FXUS61 KPHI 220145
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
945 PM EDT MON MAY 21 2012

.SYNOPSIS...
A LOW PRESSURE SYSTEM OFF THE MIDDLE ATLANTIC COAST IS FORECAST TO
DRIFT SLOWLY NORTHEAST AND REACH THE CANADIAN MARITIMES ON
WEDNESDAY. THEREAFTER AN ATLANTIC HIGH PRESSURE SYSTEM WILL BUILD
WEST AND PERSIST INTO THE START OF THE MEMORIAL DAY WEEKEND. A
BACKDOOR COLD FRONT FROM EASTERN CANADA IS THEN FORECAST TO APPROACH
AND STALL NEAR THE REGION ON SUNDAY AND MONDAY.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
THE MAIN FORECAST PROBLEM FOR THE OVERNIGHT WILL BE THE COVERAGE OF
SHOWERS...ESPECIALLY ACROSS EASTERN SECTIONS.

THE AREA OF SHOWERS THAT HAS LURKED IN THE AREA OF HIGHER PRECIPITABLE
WATER WANED EARLIER THIS EVENING...BUT HAS COME BACK INT HE PAST
90 MINUTES. THE IR IMAGES IN THE AREA EAST OF SOUTHEAST VIRGINIA
HAVE SHOWN WARMING TOPS FOR THE MOST PART. BASED ON EXTRAPOLATION
OF THE AREA OF HEAVIEST RAIN NOW EAST OF THE SOUTHERN DELAWARE
COAST...PARTS OF NORTHERN NEW JERSEY LOOK TO SEE THE HEAVIEST RAIN
OVERNIGHT. BASIN AVERAGE OF 0.75 INCHES LOOKS ABOUT RIGHT...AND
THIS MUCH ADDITIONAL RAIN SHOULD NOW RESULT IN MUCH MORE THAN
NUISANCE FLOODING.

THE NEXT FORECAST PROBLEM IS THE FOG. THE AREA OF FOG OVER
MONMOUTH AND OCEAN COUNTIES DOES NOT APPEAR TO HAVE GROWN MUCH IN
THE PAST 90 MINUTES. SURFACE OBSERVATIONS AND WEBCAMS IN THE AREA
SUGGEST THAT THE FOG IS DENSE IN SPOTS...BUT NOT ENOUGH COVERAGE
YET FOR A DENSE FOG ADVISORY. THE FOG WAS HIGHLIGHTED IN THE
LATEST FORECAST UPDATE...AND THE SPECIAL WEATHER STATEMENT WILL BE
UPDATED TO DRAW MORE ATTENTION TO IT.

NOT MUCH CHANGE IN THE TEMPERATURE AND WIND FORECASTS FOR THE
OVERNIGHT FROM THE PREVIOUS FORECAST.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/...
NOT MUCH CHANGE IN THE OVERALL TRENDS TOMORROW, EVEN THOUGH THE MDL
SOLNS AGAIN DIFFER ON HOW WET WE WILL BE.  THIS IS MAINLY DUE TO THE
FACT THAT ANY PRECIP WILL BE DEPENDENT ON THESE WAVES ON ELY FLOW
THAT HAVE BEEN DIFFICULT TO FORECAST MORE THAN A FEW HOURS IN
ADVANCE.  SO WHILE ALL MDLS FCST IT TO BE WARMER, THE MOST
OPTIMISTIC MDLS HAVE IT LESS DREARY AND THE MOST PESSIMISTIC...WELL
NOT SO MUCH...

ONCE AGAIN ANY PRECIP WAVES COULD PRODUCE LOCALLY HEAVY RAINFALL AS
THEY WILL BE SLOW MOVING, BUT OVERALL QPF WILL BE LIGHT.

&&

.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
ITS GOING TO BE A SLOW RECOVERY FROM PRECIPITATION CHANCES AS THE
LONG TERM PROGRESSES WITH SOME UNSEASONABLY WARM WEATHER EXPECTED
OVER THE MEMORIAL DAY WEEKEND. THE LAZY FLOW ALOFT IS MORE TYPICAL
OF LATE AUGUST THAN LATE MAY AND AS SUCH THE SLOW MOVING CONVECTION
WILL PRODUCE SOME LOCALLY HEAVY DOWNPOURS. CONVECTION SHOULD BE
DIURNALLY DRIVEN AND THERE WILL BE A TRAIL OFF IN THE POPS AT
NIGHT.

SO BEGINNING WITH TUESDAY NIGHT CONVECTIVE COVERAGE AND CHANCES WILL
LOWER AS THE NIGHT PROGRESSES. WE DROP THE MENTION OF THUNDER AFTER
THE EVENING. FORECAST SOUNDINGS SUGGEST EITHER LOW CLOUDS AND OR FOG
WILL FORM. FOR NOW WE KEPT THE MENTION OF PATCHY FOG AS CONFIDENCE
ABOUT ONE OVER THE OTHER IS NOT HIGH ENOUGH TO MAKE A CHOICE OR CHANGE.
STAT GUIDANCE WAS CLOSE AND ACCEPTED.

THE CLOSED LOW ACROSS THE SERN CONUS IS FORECAST TO COME CLOSER ON
WEDNESDAY DAY. WITH CONVECTIVE TEMPS FORECAST TO BE IN THE MID 70S
WITH SOME DPVA AND OMEGA FORECAST ESPECIALLY SOUTHWEST. WE UPPED
THE POPS TO LIKELY BY LATE AFTERNOON PRETTY MUCH FROM THE LEHIGH
AND DELAWARE VALLEY SOUTHWESTWARD. MODELS ARE ALSO HINTING AND
SOME CONVERGENCE FROM DIFFERENT BAY BREEZES ON THE DELMARVA
PENINSULA. DIFFERENCES AS TO FORECAST INSTAB, BUT THE OVERALL WIND
FIELD IS FORECAST TO BE VERY WEAK AND NOT MUCH OF A DROP OFF OF
THETA E WITH HEIGHT IN THE MID LEVELS. SO MAIN CONCERN LOOKS LIKE
LOCALLY HEAVY RAIN. GIVEN THE FORECAST CONVECTIVE TEMPS, STAT
GUIDANCE LOOKS REASONABLE.

WE THROTTLE DOWN THE PRECIPITATION CHANCES AGAIN ON WEDNESDAY NIGHT.
ON THURSDAY A HIGH PRESSURE SYSTEM FROM JAMES BAY IS FORECAST TO
BUILD OVER THE NEW ENGLAND COASTAL WATERS. ITS TRACK IS A BIT
FARTHER TO THE EAST THAN SOME OF THE DIRTY HIGHS WE HAVE HAD THIS
SPRING. NEVERTHELESS IT GIVES US PAUSE AS TO HOW WARM A DAY THURSDAY
WILL BE AND HOW MANY LOW CLOUDS WILL COME IN OFF THE OCEAN. AS FAR
AS POPS GO, THINKING GFS EASTWARD EMPHASIS MAY BE GIVING THE HIGH
TOO LITTLE CREDIT, SO WE LEANED HIGHEST POPS FARTHER TO THE WEST.

THE 500MB TROF IS STILL LINGERING INTO THURSDAY NIGHT AND FRIDAY, SO
WE MAINTAIN SOME CHANCES. THE MARINE INFLUENCE ON FRIDAY BY THE
SURFACE HIGH APPEARS LESS, SO WE WENT ALONG WITH A COMPROMISE
BETWEEN GFS AND EURO MOS FOR MAX TEMPS.

THEN FOR MEMORIAL DAY WEEKEND PRETTY MUCH THE GIRL WITH THE CURL
TYPE WEEKEND IT SEEMS FOR US, EITHER VERY GOOD OR VERY BAD, SELDOM
IN THE MIDDLE. THIS TIME THE MODELS ARE CONTINUING TO OUTLOOK WHAT
WOULD BE A "SUMMER" TIME WEEKEND. THERE IS PRETTY MUCH GOOD
AGREEMENT ABOUT A WARM DAY FOR SATURDAY WITH RELATIVELY SPEAKING
OUR LOWEST CHANCES FOR PRECIPITATION. AFTER THAT THERE REMAINS
DIFFERENCES AS TO HOW MUCH CAN A BACKDOOR FRONT SLIP TOWARD OR
INTO OUR CWA ON SUNDAY OR MONDAY. THE GFS HAS BEEN MORE
AGGRESSIVE. THE 12Z EURO HAS TRENDED THE GFS`S WAY BUT MORE IN A
YOU WON THE BATTLE BUT NOT NECESSARILY THE TEMPERATURE WAR. WE
HAVE SOME SLIGHT CHANCES IN BECAUSE OF THE PROXIMITY TO THE FRONT.
FOR NOW WE ARE BANKING ON NOT MUCH OF A THERMAL EFFECT FROM THE
FRONT WITH MAX TEMPS PROGGED MUCH CLOSER TO EC MOS THAN GFS MOS.

&&

.AVIATION /02Z TUESDAY THROUGH SATURDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.

THE BREAK IN THE CLOUDS OVER DELAWARE AND NORTHEAST MARYLAND NOT
WITHSTANDING...MVFR AND IFR CONDITIONS WILL TRANSITION TO LIFR
CONDITIONS OVERNIGHT. THE QUESTION BECOMES JUST HOW QUICKLY.

PATCHY LIGHT RAIN AND DRIZZLE WILL CONTINUE ACROSS THE REGION DURING
THE NEXT FEW HOURS. THE LIGHT RAIN WILL HELP TO SATURATE THE LOW
LEVELS...AND AID THE TRANSITION TO LIFR. RIGHT NOW...IT WOULD APPEAR
TO ALL LOCATIONS WILL DROP TO LIFR BY 0400 UTC...AND STAY THERE
THROUGH AT LEAST 1300 UTC. THE STATISTICAL GUIDANCE SUGGESTS THAT
THE LOWER LEVELS COULD MOISTEN ENOUGH FOR 1/2SM IN FOG AT KACY AND
KMIV BETWEEN 0800 UTC AND 1300 UTC.

THE TRANSITION FROM LIFR THROUGH IFR TO MVFR SHOULD OCCUR BETWEEN
1300 UTC AND 1600 UTC...OCCURRING FIRST AT KRDG AND KABE...AND LAST
AT KACY. THE BOUNDARY LAYER COULD WARM ENOUGH FOR SOME LOCATIONS TO
REACH VFR FOR A TIME AT THE KPHL METRO AIRPORTS TUESDAY AFTERNOON.
BREAKS COULD ALLOW FOR SCATTERED THUNDERSTORMS...BUT THE CONFIDENCE
SIMPLY IS NOT THERE TO INCLUDE IN THE FORECAST YET.

OUTLOOK...
TUESDAY NIGHT THROUGH FRIDAY...MVFR OR IFR CONDS LATER EACH NIGHT
AND EARLY EACH DAY IN STRATUS OR FOG BECOMING VFR MIDDAY INTO THE
EVENING. LOCAL MVFR OR IFR CONDS IN SHOWERS OR TSTMS. OUTLOOKING
LESS COVERAGE AND DURATION OF IFR AND MVFR CONDITIONS ON FRIDAY.

SATURDAY...POSSIBLY SOME MVFR EARLY, OTHERWISE VFR.

&&

.MARINE...
SEAS HAVE BEEN SLOWLY CREEPING UP IN THE SOUTHEASTERLY
SWELL...ASSOCIATED WITH THE PERSISTENT ONSHORE FLOW. THE LATEST
WAVEWATCH GUIDANCE HAS SEAS REACHING SMALL CRAFT LEVELS AFTER
MIDNIGHT...SO THERE WAS NO APPRECIABLE CHANGE IN THE WAVE HEIGHT
FORECAST FOR THE OVERNIGHT.

A LOCAL ENHANCEMENT ON THE PRESSURE GRADIENT HAS RESULTED IN AN
INCREASE IN THE WIND SPEEDS ACROSS THE SOUTHERNMOST OCEAN WATERS
AND THE LOWER DELAWARE BAY. WINDS ARE STILL EXPECTED TO REMAIN
BELOW SMALL CRAFT LEVELS...BUT GUSTS TO 20 KNOTS IN THIS AREA IS
POSSIBLE THROUGH ABOUT 0600 UTC.

PERHAPS THE BIGGEST FORECAST ISSUE FOR THE OVERNIGHT WILL BE THE
FOG. SURFACE OBSERVATIONS ALONG THE COAST...AS WELL AS WEBCAMS
ALONG ANZ450-451 SHOW THE FOG IN PLACE...AND IT HAS BECOME DENSE
IN SPOTS. THE SHOWERS MOVING IN FROM THE SOUTHEAST COULD BE ENOUGH
TO KEEP VISIBILITIES FROM PLUMMETING OVERNIGHT. A MARINE WEATHER STATEMENT
WAS ISSUED TO HIGHLIGHT THE FOG THREAT IN THE ABOVEMENTIONED AREAS
OVERNIGHT.

FOR TUESDAY...WINDS ARE EXPECTED TO REMAIN BELOW SMALL CRAFT
LEVELS. HOWEVER...THE SOUTHEASTERLY SWELL SHOULD REMAIN AT OR
ABOVE 5 FEET ON THE OCEAN WATERS ALL TODAY INTO THE EVENING.

OUTLOOK...
WE ARE EXPECTING SMALL CRAFT ADVISORY CONDITIONS FROM SEAS TO
PERSIST INTO TUESDAY NIGHT. AFTER THAT WE ARE NOT OUTLOOKING SMALL
CRAFT ADVISORY CONDITIONS TO BE MET THROUGH THE REST OF THE
DETERMINISTIC FORECAST. THE ONSHORE GRADIENT AND SWELLS FROM THE
HIGH BUILDING ACROSS THE CANADIAN MARITIMES IS NOT EXPECTED TO BE
STRONG ENOUGH TO GENERATE SMALL CRAFT CONDITIONS CENTERED AROUND
THURSDAY. AFTER THAT THE HIGH BUILDS FARTHER INTO OUR MARINE AREA
REDUCING THE THREAT OF SMALL CRAFT CONDITIONS EVEN FURTHER. THE
APPROACHING BACK DOOR FRONT SHOULD NOT BE AN ISSUE, IF EVER AT ALL,
THROUGH SATURDAY.

&&

.HYDROLOGY...
IT LOOKS LIKE NORTHERN NEW JERSEY WILL BE THE LOCATION THAT SEES
THE MOST RAIN DURING THE OVERNIGHT. BASED ON THE LATEST MODEL
FORECASTS (WITH THE GFS DOING A MUCH BETTER JOB WITH THE PLACEMENT
OF THE RAIN THAN THE NAM THIS AFTERNOON)...AS MUCH AS AN INCH OF
RAIN COULD FALL BASINWIDE IN THIS AREA.

UPDATED FLASH FLOOD AND HEADWATER GUIDANCE SUGGESTS THAT 1 TO 2
INCHES OF RAIN WOULD NEED TO FALL IN NORTHERN NEW JERSEY BEFORE
PROBLEMS STARTED. THIS IS NOT EXPECTED OVERNIGHT.

SHOULD THE AXIS OF HEAVIEST OVERNIGHT RAIN COME IN FURTHER
SOUTHWEST...ANY SMALL STREAM FLOOD PROBLEMS WOULD MORE LIKELY
OCCUR IN EASTERN PENNSYLVANIA WHERE GRIDDED FLASH FLOOD GUIDANCE
SHOWS GREATER VULNERABILITY. 1 HR FFG NEAR 1.3 INCHES AND 6 TO 24
HR GUIDANCE IS CURRENTLY NEAR 1.9 INCHES.

&&

.RIP CURRENTS...
SWELL HEIGHTS NEAR 5 FEET...COMBINED WITH A DOMINANT 9 SECOND
PERIOD...WILL OUTWEIGH THE SLACKENING PRESSURE GRADIENT TUESDAY.
THE COMBINATION OF THE SWELL HEIGHT AND RELATIVELY LONG PERIOD
WILL RESULT IN A MODERATE RISK OF RIP CURRENTS TUESDAY. WHILE THE
COMBINATION SHOULD HAVE A LESSER EFFECT ON THE DELAWARE
BEACHES...IT WAS INCLUDED IN THE MODERATE RISK.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 AM EDT
     WEDNESDAY FOR ANZ450>455.

&&

$$

SYNOPSIS...GIGI
NEAR TERM...HAYES
SHORT TERM...NIERENBERG
LONG TERM...GIGI
AVIATION...GIGI/HAYES
MARINE...GIGI/NIERENBERG
HYDROLOGY...GIGI/HAYES
RIP CURRENTS...HAYES

000
FXUS61 KCTP 220043
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
843 PM EDT MON MAY 21 2012

.SYNOPSIS...
AN UPPER LOW OVER THE SOUTHEAST COAST WILL OPEN UP AND LIFT
TONIGHT. A DEEPENING SHORTWAVE WILL SLOW DOWN AND CUT OFF OVR THE
CENTRAL APPALACHIANS DURING THE MIDDLE OF THE WEEK. PENNSYLVANIA
WILL BE ON THE EDGE OF THE REBUILDING UPPER RIDGE ACROSS THE OHIO
VALLEY BY THE END OF WEEK. THIS BUILDING RIDGE WILL KEEP WARM
TEMPERATURES ACROSS THE REGION INTO THE HOLIDAY WEEKEND.

&&

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

UPPER LOW OVER THE CAROLINA COAST WILL LIFT NORTH ALONG THE E
COAST DURING THE NEXT 24HRS. MOIST...EASTERLY LL JET AND UPPER
LVL DIVERGENCE PRECEDING THE UPPER LOW WILL BRING SHOWERS TO MOST
OF CENTRAL PA THROUGH TONIGHT. MAIN BAND OF SHOWERS WILL MOVE
THROUGH THE CENTER OF THE STATE OVERNIGHT. THE CIRCULATION AROUND
A BROAD UPPER LOW OVER THE SOUTHEASTERN UNITED STATES AND WESTERN
ATLANTIC AND SFC HIGH TO THE EAST OF NEW ENGLAND IS DIRECTING
HIGHER PW AIR INTO SOUTHEAST AND CENTRAL PA COINCIDING WITH
MARITIME EASTERLY FLOW PROGRESSING WNW INTO THE ALLEGHENIES. THE
PRECIP IS MOVING SLOWLY...BUT A LIGHT ENOUGH INTENSITY WHERE
FLOODING ISNT A THREAT. HOWEVER WILL CONTINUE TO KEEP AN EYE ON
THINGS...AS IT HAS BEEN WET THE LAST 2 WEEKS.

PRECIP WILL CONTINUE OVERNIGHT BUT FADE INTO TOMORROW
MORNING...WITH PRECIP ENDING FROM THIS BAND.


&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/...
A GENERAL DECREASE IN SHOWER ACTIVITY IS EXPECTED LATE AS UPPER
LOW OPENS UP AND LIFTS NE. BIGGER STORY EARLY TUESDAY MORNING COULD BE
AREAS OF POTENTIALLY DENSE FOG. PLENTY OF LL MOISTURE AND A NEARLY
CALM WIND WILL BE FAVORABLE FOR FOG.

AS E COAST UPPER LOW OPENS UP AND LIFTS INTO THE CANADIAN
MARITIMES...UPSTREAM SHORTWAVE WILL DEEPEN AND CUTOFF OVR THE
TN VALLEY ON TUESDAY. LG SCALE FORCING AHEAD OF THIS FEATURE WILL
PRODUCE MORE SHRA/TSRA...MAINLY DURING THE AFT...AS SOME HEATING
TAKES PLACE...AND TEMPS WARM INTO THE 70S. GEFS/SREF DATA BOTH
SUGGEST BEST CHC OF SHRA/TSRA WILL BE ALONG THE SPINE OF THE
APPALACHIANS. OVERCAST SKIES AND VERY LGT WINDS ALOFT SUGGEST
THERE WILL BE VERY LITTLE THREAT OF SVR WX. BLEND OF GEFS/SREF
QPF RANGES FROM 0.2 TO 0.3 INCHES TONIGHT AND TUESDAY.

&&

.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
STILL SOME CHC OF A SHOWER OR THUNDERSTORM WED INTO FRIDAY...
MAINLY ACROSS THE SE DURING THE AFTERNOON AND PERHAPS EARLY
EVENING HOURS...AS THE REMAINS OF THE UPPER LVL LOW REMAIN
NEARBY.

GFS AND OTHERS MORE IN LINE WITH KEEPING FRONT NORTH OF OUR
AREA THIS COMING HOLIDAY WEEKEND...GFS WAS TOO COLD AND TOO
FAR SOUTH YESTERDAY WITH THINGS. EC HAS BEEN HINTING AT A
LARGE RIDGE BUILDING EASTWARD WITH TIME...AND VERY WARM
TEMPS. LEFT FCST DRY AFTER SAT...AS IF FRONT MAKES INTO
N PA...IT WOULD HAVE VERY LITTLE SUPPORT AND NOT MUCH MORE
THAN A WIND SHIFT LINE.

&&

.AVIATION /01Z TUESDAY THROUGH SATURDAY/...
GENERALLY MVFR CONDITIONS PERSIST ACROSS THE REGION THIS EVENING
AS THE AREA IS UNDER THE INFLUENCE OF LARGE UPPER LEVEL TROF AND
LOWER LEVEL EASTERLY FLOW. EXPECT MOST AREAS TO DROP INTO IFR
CONDITIONS OVERNIGHT WITH LIGHT WINDS...FOG AND LOWERING CIGS AS
AN UPPER LEVEL TROF APPROACHES FROM THE GREAT LAKES.

SOME DIURNAL IMPROVEMENT IN CONDITIONS POSSIBLE TUESDAY AFTERNOON
AS UPPER FLOW BECOMES A BIT MORE SOUTHERLY IN ADVANCE OF NEWLY
DEVELOPING TN VALLEY UPPER LEVEL LOW. WITH THE POTENTIAL INCREASE
IN CIGS AND VSBYS WILL BE INCREASING CHANCES OF SHOWERS AND
POSSIBLE TSRA.

OUTLOOK...
WED...WIDESPREAD MVFR/IFR CIGS AND VSBYS LIKELY IN SHRA AND SCT
TSRA.
THU...PRIMARILY VFR. SCT SHRA/TSRA POSS MAINLY SE.
FRI...PRIMARILY VFR. ISOLD SHRA/TSRA POSS MAINLY SE.
SAT...VFR. A CHC OF A SHRA OR TSRA ACROSS THE NORTH.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...DEVOIR/MARTIN
NEAR TERM...CERU/MARTIN
SHORT TERM...DEVOIR/FITZGERALD/MARTIN
LONG TERM...MARTIN
AVIATION...JUNG

000
FXUS61 KPBZ 220014
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
814 PM EDT MON MAY 21 2012

.SYNOPSIS...
RAIN CHANCES WILL BE ON THE INCREASE THROUGH TUESDAY AS A COLD
FRONT SLOWLY APPROACHES FROM THE WEST AND AS LOW PRESSURE MOVES UP
THE EAST COAST.

&&

.NEAR TERM /THROUGH TUESDAY/...
AN EARLY EVENING UPDATE HAS BEEN ISSUED TO ACCOUNT FOR THE LATEST
TRENDS IN RADAR AND SKY COVERAGE.

RAP MID-LEVEL ANALYSIS A BROAD MID-LEVEL TROUGH EXTENDING ACROSS
THE OHIO VALLEY. MSAS SURFACE ANALYSIS INDICATES A WEAK LOW
CENTERED ACROSS CENTRAL OHIO WITH A NORTH- SOUTH ORIENTED FRONTAL
BOUNDARY BISECTING THE STATE. A POCKET OF DEW POINTS IN THE LOWER
50S IS LOCATED IN EASTERN OHIO. SKIES REMAIN CLEAR IN THIS POCKET
WITH SCATTERED SHOWERS AND THUNDERSTORMS DEVELOPING IN LOCATIONS
TO THE EAST AND WEST WHERE TDS ARE IN THE UPPER 50S TO LOWER 60S.
POCKETS OF MODERATE INSTABILITY LOCATED WITH LITTLE OR WIND SHEAR
HAVE ALLOWED FOR VERY SLOW MOVING SHOWERS AND THUNDERSTORMS WITH
HEAVY DOWNPOURS THIS EVENING IN WESTERN PA AND NORTH-CENTRAL WV.

THIS EVENING AND TONIGHT...THE BROAD MID-LEVEL TROUGH WILL
CONTINUE TO MOVE SLOWLY ACROSS THE OHIO VALLEY. MODERATE INSTABILITY
WILL FUEL CONVECTION EARLY WITH WEAK WINDS ALOFT ALLOWING FOR
SHOWERS AND THUNDERSTORMS TO HAVE VERY LITTLE MOVEMENT. SCATTERED
COVERAGE WILL BECOME MORE ISOLATED WITH THE LOSS OF HEATING AND
INHERENT INSTABILITY TONIGHT. THE POTENTIAL OF LOCALLY HEAVY
RAINFALL LEADING TO MINOR FLOODING HAS BEEN MENTIONED THE HWO.

OVERNIGHT LOWS WILL REMAIN RELATIVELY WARM AS INCREASED BOUNDARY
LAYER MOISTURE WILL PRECLUDE A DRAMATIC DROP. TEMPERATURES ARE
FAIRLY CLOSE TO LAMP GUIDANCE OVERNIGHT, WITH LOWS IN RANGING FROM
THE MID 50S ACROSS THE EASTERN RIDGES TO THE LOWER 60S IN PORTIONS
OF EASTERN OHIO.

&&

.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
PROGRESS OF THE FRONT WILL BE SLOW GIVEN THE AFOREMENTIONED WEAKNESS
OF THE OVERALL WIND FIELD. WITH PERSISTENT UPPER/MID LEVEL TROUGH FORECAST
OVER THE EASTERN CONUS...EXPECT CONVECTIVE TEMPERATURES TO REMAIN SUFFICIENTLY
LOW FOR DIURNALLY SUPPORTED SHOWER AND THUNDERSTORM DEVELOPMENT WITH
FOCUS VIA THE FRONT...RIDGES...OR OUTFLOW BOUNDARIES. WILL THUS FORECAST
LIKELY POPS ON TUESDAY WITH PASSAGE OF THE FRONT...FOLLOWED BY SCATTERED
PRECIP POTENTIAL THROUGH THE REMAINDER OF THE SHORT TERM.

WARM...HUMID CONDITIONS CAN BE EXPECTED TO CONTINUE THROUGH THE PERIOD.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
UPPER TROUGH MOVING OFF TO THE EAST WILL STILL SPAWN ISOLATED
SHOWERS/THUNDERSTORMS FRIDAY. AFTER THAT...UPPER RIDGE WILL BUILD
INTO THE REGION AND REMAIN NEARLY STATIONARY. ISOLATED
SHOWERS/THUNDERSTORMS CANNOT BE RULED OUT AS A WEAK SURFACE FRONT
TRIES TO MOVE THROUGH. TEMPERATURES SHOULD BE WELL ABOVE
NORMAL...WITH UPPER 80S AND LOWER 90S EXPECTED FOR THE HOLIDAY
WEEKEND.

&&

.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
SCATTERED EVENING SHOWERS HAVE SUBSIDED AND WILL CONTINUE TO
WEAKEN AFTER SUNSET. ALL PORTS ESCAPED SIGNIFICANT RAIN THIS
EVENING WHICH MAY LIMIT FOG THREAT TOWARD DAYBREAK. HAVE USED
JUST MVFR FOG LEVELS FOR THE EARLY MORNING WITH GENERAL VFR
CONDITIONS FOR TUESDAY. A WEAK COLD FRONT WILL PUSH THROUGH
THE DISTRICT BY TUESDAY AFTERNOON...BRINGING A THREAT OF
SHOWERS AND THUNDERSTORMS.

.OUTLOOK...TUESDAY NIGHT THROUGH SATURDAY...
SCATTERED SHOWERS ARE POSSIBLE THROUGH THURSDAY...WITH DIURNAL
CYCLE BRINGING GREATER COVERAGE DURING THE DAYTIME HOURS THAN
NIGHTTIME HOURS. AS THE FRONT STALLS EAST OF THE DISTRICT
TUESDAY EVENING... SURFACE DEW POINTS WILL REMAIN ELEVATED
AND WILL LIKELY RESULT IN MVFR VISIBILITY RESTRICTIONS IN FOG AT MOST
AIRPORT LOCATIONS DURING THE EARLY MORNING HOURS THROUGH THURSDAY.
COVERAGE OF SHOWERS SHOULD BE ISOLATED FOR FRIDAY AND SATURDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$

000
FXUS61 KPHI 212349
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
749 PM EDT MON MAY 21 2012

.SYNOPSIS...
A LOW PRESSURE SYSTEM OFF THE MIDDLE ATLANTIC COAST IS FORECAST TO
DRIFT SLOWLY NORTHEAST AND REACH THE CANADIAN MARITIMES ON
WEDNESDAY. THEREAFTER AN ATLANTIC HIGH PRESSURE SYSTEM WILL BUILD
WEST AND PERSIST INTO THE START OF THE MEMORIAL DAY WEEKEND. A
BACKDOOR COLD FRONT FROM EASTERN CANADA IS THEN FORECAST TO APPROACH
AND STALL NEAR THE REGION ON SUNDAY AND MONDAY.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
THE MAIN FORECAST PROBLEM FOR THE OVERNIGHT WILL BE THE COVERAGE OF
SHOWERS...ESPECIALLY ACROSS EASTERN SECTIONS.

THE TRAIN OF SHOWERS THAT EXTENDED FROM EAST OF THE VIRGINIA COAST
INTO SOUTHEAST NEW YORK STATE IS STILL MORE OR LESS IN PLACE. THERE
APPEARS TO BE ANOTHER AREAS OF MORE CONVECTIVE LOOKING SHOWERS
APPROACHING SOUTHERNMOST NEW JERSEY EARLY THIS EVENING. THE TRAIN IS
LODGED IN AN AXIS OF HIGH PRECIPITABLE WATER (LATEST ANALYSIS SHOWS
PRECIPITABLE WATER VALUES NEAR 1.60 INCHES).

THERE HAS BEEN SOME LIGHTNING ON THE SOUTHERN EDGE OF THE TRAIN EAST
OF THE VIRGINIA COAST...BUT THE WARM CORE PROCESSES THIS FAR NORTH
ARE NOT PRODUCING ENOUGH CHARGE SEPARATION FOR LIGHTNING. NEAR AND
SHORT TERM MODELS ARE SHOWING SOME SPREAD ON JUST HOW MUCH OF THE
ACTIVITY TO THE SOUTH GETS INTO NEW JERSEY LATER THIS EVENING. HEAVY
RAIN EARLIER TODAY PRODUCED 1 TO 2 INCHES OF RAIN ACROSS PORTIONS OF
NORTH CENTRAL NEW JERSEY...AS WELL AS THE MONMOUTH COUNTY COAST.

AT THIS POINT...IT DOES NOT APPEAR AS THOUGH THE ADDITIONAL RAIN
WOULD HIT THE ABOVEMENTIONED AREAS HARD AGAIN THIS EVENING. MOST
AREAS SHOULD BE ABLE TO ABSORB THE ADDITIONAL RAINFALL WITH LOCAL
NUISANCE FLOODING EXPECTED.

A HOLE IN THE OVERCAST HAS MOVED INTO DELAWARE AND NORTHEAST
MARYLAND. THE AIRMASS HAS RESPONDED BY BECOMING MARGINALLY UNSTABLE.
HOWEVER...THE INSTABILITY HAS NO FOCUS OR UPSTREAM MEANS FOR
RELEASE...SO AT THIS POINT...THE MENTION OF THUNDER WILL BE REMOVED
FROM THE FORECAST. THE AREA OF CLEARING SHOULD FILL BACK IN AS LOWER
CLOUDS FORM AGAIN IN THE MOISTENING LOW LEVEL FLOW.

DEW POINTS HAVE CLIMBED INTO THE 60S ACROSS THE AREA. WITH LITTLE
CHANGE IN THE AIRMASS OVERNIGHT...THE DEW POINTS SHOULD ACT AS A
LOWER END OF THE RANGE FOR LOWS. THIS IS MORE OR LESS WHAT MOS
VALUES ARE SHOWING FOR LOWS...AND A BLEND OF THOSE NUMBERS IS
ACCEPTED. THE BOUNDARY CONDITIONS NEAR A WASHING OUT WARM FRONT
ARE INDEED ALLOWING FOG TO DEVELOP NEAR THE MONMOUTH AND OCEAN
COUNTY COAST THIS EVENING. STATISTICAL GUIDANCE SUGGESTS THAT MUCH
OF EASTERN NEW JERSEY GETS INTO THE FOG...AND THE FORECAST WAS
UPDATED TO INDICATE THIS.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/...
NOT MUCH CHANGE IN THE OVERALL TRENDS TOMORROW, EVEN THOUGH THE MDL
SOLNS AGAIN DIFFER ON HOW WET WE WILL BE.  THIS IS MAINLY DUE TO THE
FACT THAT ANY PRECIP WILL BE DEPENDENT ON THESE WAVES ON ELY FLOW
THAT HAVE BEEN DIFFICULT TO FORECAST MORE THAN A FEW HOURS IN
ADVANCE.  SO WHILE ALL MDLS FCST IT TO BE WARMER, THE MOST
OPTIMISTIC MDLS HAVE IT LESS DREARY AND THE MOST PESSIMISTIC...WELL
NOT SO MUCH...

ONCE AGAIN ANY PRECIP WAVES COULD PRODUCE LOCALLY HEAVY RAINFALL AS
THEY WILL BE SLOW MOVING, BUT OVERALL QPF WILL BE LIGHT.

&&

.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
ITS GOING TO BE A SLOW RECOVERY FROM PRECIPITATION CHANCES AS THE
LONG TERM PROGRESSES WITH SOME UNSEASONABLY WARM WEATHER EXPECTED
OVER THE MEMORIAL DAY WEEKEND. THE LAZY FLOW ALOFT IS MORE TYPICAL
OF LATE AUGUST THAN LATE MAY AND AS SUCH THE SLOW MOVING CONVECTION
WILL PRODUCE SOME LOCALLY HEAVY DOWNPOURS. CONVECTION SHOULD BE
DIURNALLY DRIVEN AND THERE WILL BE A TRAIL OFF IN THE POPS AT
NIGHT.

SO BEGINNING WITH TUESDAY NIGHT CONVECTIVE COVERAGE AND CHANCES WILL
LOWER AS THE NIGHT PROGRESSES. WE DROP THE MENTION OF THUNDER AFTER
THE EVENING. FORECAST SOUNDINGS SUGGEST EITHER LOW CLOUDS AND OR FOG
WILL FORM. FOR NOW WE KEPT THE MENTION OF PATCHY FOG AS CONFIDENCE
ABOUT ONE OVER THE OTHER IS NOT HIGH ENOUGH TO MAKE A CHOICE OR CHANGE.
STAT GUIDANCE WAS CLOSE AND ACCEPTED.

THE CLOSED LOW ACROSS THE SERN CONUS IS FORECAST TO COME CLOSER ON
WEDNESDAY DAY. WITH CONVECTIVE TEMPS FORECAST TO BE IN THE MID 70S
WITH SOME DPVA AND OMEGA FORECAST ESPECIALLY SOUTHWEST. WE UPPED
THE POPS TO LIKELY BY LATE AFTERNOON PRETTY MUCH FROM THE LEHIGH
AND DELAWARE VALLEY SOUTHWESTWARD. MODELS ARE ALSO HINTING AND
SOME CONVERGENCE FROM DIFFERENT BAY BREEZES ON THE DELMARVA
PENINSULA. DIFFERENCES AS TO FORECAST INSTAB, BUT THE OVERALL WIND
FIELD IS FORECAST TO BE VERY WEAK AND NOT MUCH OF A DROP OFF OF
THETA E WITH HEIGHT IN THE MID LEVELS. SO MAIN CONCERN LOOKS LIKE
LOCALLY HEAVY RAIN. GIVEN THE FORECAST CONVECTIVE TEMPS, STAT
GUIDANCE LOOKS REASONABLE.

WE THROTTLE DOWN THE PRECIPITATION CHANCES AGAIN ON WEDNESDAY NIGHT.
ON THURSDAY A HIGH PRESSURE SYSTEM FROM JAMES BAY IS FORECAST TO
BUILD OVER THE NEW ENGLAND COASTAL WATERS. ITS TRACK IS A BIT
FARTHER TO THE EAST THAN SOME OF THE DIRTY HIGHS WE HAVE HAD THIS
SPRING. NEVERTHELESS IT GIVES US PAUSE AS TO HOW WARM A DAY THURSDAY
WILL BE AND HOW MANY LOW CLOUDS WILL COME IN OFF THE OCEAN. AS FAR
AS POPS GO, THINKING GFS EASTWARD EMPHASIS MAY BE GIVING THE HIGH
TOO LITTLE CREDIT, SO WE LEANED HIGHEST POPS FARTHER TO THE WEST.

THE 500MB TROF IS STILL LINGERING INTO THURSDAY NIGHT AND FRIDAY, SO
WE MAINTAIN SOME CHANCES. THE MARINE INFLUENCE ON FRIDAY BY THE
SURFACE HIGH APPEARS LESS, SO WE WENT ALONG WITH A COMPROMISE
BETWEEN GFS AND EURO MOS FOR MAX TEMPS.

THEN FOR MEMORIAL DAY WEEKEND PRETTY MUCH THE GIRL WITH THE CURL
TYPE WEEKEND IT SEEMS FOR US, EITHER VERY GOOD OR VERY BAD, SELDOM
IN THE MIDDLE. THIS TIME THE MODELS ARE CONTINUING TO OUTLOOK WHAT
WOULD BE A "SUMMER" TIME WEEKEND. THERE IS PRETTY MUCH GOOD
AGREEMENT ABOUT A WARM DAY FOR SATURDAY WITH RELATIVELY SPEAKING
OUR LOWEST CHANCES FOR PRECIPITATION. AFTER THAT THERE REMAINS
DIFFERENCES AS TO HOW MUCH CAN A BACKDOOR FRONT SLIP TOWARD OR
INTO OUR CWA ON SUNDAY OR MONDAY. THE GFS HAS BEEN MORE
AGGRESSIVE. THE 12Z EURO HAS TRENDED THE GFS`S WAY BUT MORE IN A
YOU WON THE BATTLE BUT NOT NECESSARILY THE TEMPERATURE WAR. WE
HAVE SOME SLIGHT CHANCES IN BECAUSE OF THE PROXIMITY TO THE FRONT.
FOR NOW WE ARE BANKING ON NOT MUCH OF A THERMAL EFFECT FROM THE
FRONT WITH MAX TEMPS PROGGED MUCH CLOSER TO EC MOS THAN GFS MOS.

&&

.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.

THE BREAK IN THE CLOUDS OVER DELAWARE AND NORTHEAST MARYLAND NOT
WITHSTANDING...MVFR AND IFR CONDITIONS WILL TRANSITION TO LIFR
CONDITIONS OVERNIGHT. THE QUESTION BECOMES JUST HOW QUICKLY.

PATCHY LIGHT RAIN AND DRIZZLE WILL CONTINUE ACROSS THE REGION DURING
THE NEXT FEW HOURS. THE LIGHT RAIN WILL HELP TO SATURATE THE LOW
LEVELS...AND AID THE TRANSITION TO LIFR. RIGHT NOW...IT WOULD APPEAR
TO ALL LOCATIONS WILL DROP TO LIFR BY 0400 UTC...AND STAY THERE
THROUGH AT LEAST 1300 UTC. THE STATISTICAL GUIDANCE SUGGESTS THAT
THE LOWER LEVELS COULD MOISTEN ENOUGH FOR 1/2SM IN FOG AT KACY AND
KMIV BETWEEN 0800 UTC AND 1300 UTC.

THE TRANSITION FROM LIFR THROUGH IFR TO MVFR SHOULD OCCUR BETWEEN
1300 UTC AND 1600 UTC...OCCURRING FIRST AT KRDG AND KABE...AND LAST
AT KACY. THE BOUNDARY LAYER COULD WARM ENOUGH FOR SOME LOCATIONS TO
REACH VFR FOR A TIME AT THE KPHL METRO AIRPORTS TUESDAY AFTERNOON.
BREAKS COULD ALLOW FOR SCATTERED THUNDERSTORMS...BUT THE CONFIDENCE
SIMPLY IS NOT THERE TO INCLUDE IN THE FORECAST YET.

OUTLOOK...
TUESDAY NIGHT THROUGH FRIDAY...MVFR OR IFR CONDS LATER EACH NIGHT
AND EARLY EACH DAY IN STRATUS OR FOG BECOMING VFR MIDDAY INTO THE
EVENING. LOCAL MVFR OR IFR CONDS IN SHOWERS OR TSTMS. OUTLOOKING
LESS COVERAGE AND DURATION OF IFR AND MVFR CONDITIONS ON FRIDAY.

SATURDAY...POSSIBLY SOME MVFR EARLY, OTHERWISE VFR.

&&

.MARINE...
THE PROLONGED ELY TO EVENTUALLY SELY FLOW WILL CONTINUE AND THE SCA
REMAINS IN PLACE.  WE OPTED TO CONVERT IT TO A SCA FOR HIGH SEAS AS
WE DON`T BELIEVE WINDS WILL PROLONGED BE A SIGNIFICANT FACTOR
OUTSIDE OF ANY SHOWERS OR TSTMS.  SO FAR THIS AFTN, SEAS HAVE
REMAINED BELOW CRITERIA, BUT WITH A LARGE AREA OF PRECIP OFF THE
COAST AND RADAR SHOWING ENHANCEMENT, EXPECT THINGS TO PICK UP.

OUTLOOK...
WE ARE EXPECTING SMALL CRAFT ADVISORY CONDITIONS FROM SEAS TO
PERSIST INTO TUESDAY NIGHT. AFTER THAT WE ARE NOT OUTLOOKING SMALL
CRAFT ADVISORY CONDITIONS TO BE MET THROUGH THE REST OF THE
DETERMINISTIC FORECAST. THE ONSHORE GRADIENT AND SWELLS FROM THE
HIGH BUILDING ACROSS THE CANADIAN MARITIMES IS NOT EXPECTED TO BE
STRONG ENOUGH TO GENERATE SMALL CRAFT CONDITIONS CENTERED AROUND
THURSDAY. AFTER THAT THE HIGH BUILDS FARTHER INTO OUR MARINE AREA
REDUCING THE THREAT OF SMALL CRAFT CONDITIONS EVEN FURTHER. THE
APPROACHING BACK DOOR FRONT SHOULD NOT BE AN ISSUE, IF EVER AT ALL,
THROUGH SATURDAY.

&&

.HYDROLOGY...
OCCASIONAL INSTABILITY IN ASSOCIATION WITH PERSISTENTLY HIGH HUMIDITY
AND COOL TROUGHING ALOFT WILL YIELD SOME LOCALLY HEAVY DOWNPOURS.
MOST OF THE AREA SHOULD RECEIVE HALF AN INCH THIS WEEK...INCLUDING
AMOUNTS THAT BEGAN THIS PAST SUNDAY EVENING. IF THERE WERE TO BE ANY
SMALL STREAM FLOOD PROBLEMS...IT WOULD MORE LIKELY OCCUR IN EASTERN
PENNSYLVANIA OR NORTHERN NEW JERSEY WHERE GRIDDED FLASH FLOOD
GUIDANCE SHOWS GREATER VULNERABILITY. 1 HR FFG NEAR 1.3 INCHES AND 6
TO 24 HR GUIDANCE IS CURRENTLY NEAR 1.9 INCHES. THAT WOULD PLACE
MONTGOMERY...WITH THE NEARBY CHESTER COUNTY PA BORDER AND CENTRAL
MORRIS COUNTY NJ AS SEEMINGLY MOST VULNERABLE.

&&

.RIP CURRENTS...
SWELL HEIGHTS NEAR 5 FEET...COMBINED WITH A DOMINANT 9 SECOND
PERIOD...WILL OUTWEIGH THE SLACKENING PRESSURE GRADIENT TUESDAY.
THE COMBINATION OF THE SWELL HEIGHT AND RELATIVELY LONG PERIOD
WILL RESULT IN A MODERATE RISK OF RIP CURRENTS TUESDAY. WHILE THE
COMBINATION SHOULD HAVE A LESSER EFFECT ON THE DELAWARE
BEACHES...IT WAS INCLUDED IN THE MODERATE RISK.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 AM EDT
     WEDNESDAY FOR ANZ450>455.

&&

$$

SYNOPSIS...GIGI
NEAR TERM...HAYES
SHORT TERM...NIERENBERG
LONG TERM...GIGI
AVIATION...GIGI/HAYES
MARINE...GIGI/NIERENBERG
HYDROLOGY...GIGI
RIP CURRENTS...HAYES

000
FXUS61 KCTP 212345
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
745 PM EDT MON MAY 21 2012

.SYNOPSIS...
AN UPPER LOW OVER THE SOUTHEAST COAST WILL OPEN UP AND LIFT
TONIGHT. A DEEPENING SHORTWAVE WILL SLOW DOWN AND CUT OFF OVR THE
CENTRAL APPALACHIANS DURING THE MIDDLE OF THE WEEK. PENNSYLVANIA
WILL BE ON THE EDGE OF THE REBUILDING UPPER RIDGE ACROSS THE OHIO
VALLEY BY THE END OF WEEK. THIS BUILDING RIDGE WILL KEEP WARM
TEMPERATURES ACROSS THE REGION INTO THE HOLIDAY WEEKEND.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
UPPER LOW OVER THE CAROLINA COAST WILL LIFT NORTH ALONG THE E
COAST DURING THE NEXT 24HRS. MOIST...EASTERLY LL JET AND UPPER
LVL DIVERGENCE PRECEDING THE UPPER LOW WILL BRING SHOWERS TO MOST
OF CENTRAL PA THROUGH TONIGHT. CIRCULATION AROUND BROAD UPPER LOW
OVER THE SOUTHEASTERN UNITED STATES AND WESTERN ATLANTIC AND SFC
HIGH TO THE EAST OF NEW ENGLAND IS DIRECTING HIGHER PW AIR INTO
SOUTHEAST AND CENTRAL PA THIS AFT...COINCIDING WITH MARITIME
EASTERLY FLOW PROGRESSING WNW INTO THE ALLEGHENIES. MOIST AND
COOLER EASTERLY LLVL FLOW IS LIMITING CAPE...BUT SHOWERS ARE
TAPPING THE 1.5" PW AIR AND HAVE SOME TROPICAL CHARACTERISTICS
WITH QUICK DOWNPOURS PRODUCING ONE TO TWO TENTHS OF AN INCH IN 15
TO 20 MINUTES. SHOWERS ARE MOVING ALONG NICELY SO NO FLOOD THREAT...
BUT WILL CONTINUE TO KEEP AN EYE ON THINGS...AS IT HAS BEEN WET
THE LAST 2 WEEKS.

BEST CONVERGENCE ALONG THE NOSE OF THE LLVL SELY FLOW PUSHES INTO
WESTERN AND NORTHERN PA THIS AFTERNOON. SOME CHC OF THUNDER IN
THESE AREAS...AS TEMPS HAVE WARMED UP NICELY TO THE NORTH AND WEST.
CAPES MAY NEAR 1000 IN THESE AREAS.

THE LARGEST AREA OF SHOWERS IS NOW LIFTING NW FROM JUST WEST
OF MDT.

CLOUD COVER...PRECIP AND EASTERLY FLOW OFF THE ATLANTIC WILL
RESULT IN MUCH COOLER TEMPS DURING THE DAY AND MILDER TEMPS
AT NIGHT...THEN OVER THE PAST WEEKEND.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/...
SCT SHRA WILL CONTINUE TO FALL OVER CENTRAL PA TONIGHT...AS MOIST
EASTERLY LL JET AND UPPER LVL DIVERGENCE REMAIN OVR THE AREA IN
ADVANCE OF UPPER LOW. A GENERAL DECREASE IN SHOWER ACTIVITY IS
EXPECTED LATE AS UPPER LOW OPENS UP AND LIFTS NE. BIGGER STORY
LATE TONIGHT COULD BE AREAS OF POTENTIALLY DENSE FOG. PLENTY OF
LL MOISTURE AND A NEARLY CALM WIND WILL BE FAVORABLE FOR FOG.

AS E COAST UPPER LOW OPENS UP AND LIFTS INTO THE CANADIAN
MARITIMES...UPSTREAM SHORTWAVE WILL DEEPEN AND CUTOFF OVR THE
TN VALLEY ON TUESDAY. LG SCALE FORCING AHEAD OF THIS FEATURE WILL
PRODUCE MORE SHRA/TSRA...MAINLY DURING THE AFT...AS SOME HEATING
TAKES PLACE...AND TEMPS WARM INTO THE 70S. GEFS/SREF DATA BOTH
SUGGEST BEST CHC OF SHRA/TSRA WILL BE ALONG THE SPINE OF THE
APPALACHIANS. OVERCAST SKIES AND VERY LGT WINDS ALOFT SUGGEST
THERE WILL BE VERY LITTLE THREAT OF SVR WX. BLEND OF GEFS/SREF
QPF RANGES FROM 0.2 TO 0.3 INCHES TONIGHT AND TUESDAY.

&&

.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
STILL SOME CHC OF A SHOWER OR THUNDERSTORM WED INTO FRIDAY...
MAINLY ACROSS THE SE DURING THE AFTERNOON AND PERHAPS EARLY
EVENING HOURS...AS THE REMAINS OF THE UPPER LVL LOW REMAIN
NEARBY.

GFS AND OTHERS MORE IN LINE WITH KEEPING FRONT NORTH OF OUR
AREA THIS COMING HOLIDAY WEEKEND...GFS WAS TOO COLD AND TOO
FAR SOUTH YESTERDAY WITH THINGS. EC HAS BEEN HINTING AT A
LARGE RIDGE BUILDING EASTWARD WITH TIME...AND VERY WARM
TEMPS. LEFT FCST DRY AFTER SAT...AS IF FRONT MAKES INTO
N PA...IT WOULD HAVE VERY LITTLE SUPPORT AND NOT MUCH MORE
THAN A WIND SHIFT LINE.

&&

.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
GENERALLY MVFR CONDITIONS PERSIST ACROSS THE REGION THIS EVENING
AS THE AREA IS UNDER THE INFLUENCE OF LARGE UPPER LEVEL TROF AND
LOWER LEVEL EASTERLY FLOW. EXPECT MOST AREAS TO DROP INTO IFR
CONDITIONS OVERNIGHT WITH LIGHT WINDS...FOG AND LOWERING CIGS AS
AN UPPER LEVEL TROF APPROACHES FROM THE GREAT LAKES.

SOME DIURNAL IMPROVEMENT IN CONDITIONS POSSIBLE TUESDAY AFTERNOON
AS UPPER FLOW BECOMES A BIT MORE SOUTHERLY IN ADVANCE OF NEWLY
DEVELOPING TN VALLEY UPPER LEVEL LOW. WITH THE POTENTIAL INCREASE
IN CIGS AND VSBYS WILL BE INCREASING CHANCES OF SHOWERS AND
POSSIBLE TSRA.

OUTLOOK...
WED...WIDESPREAD MVFR/IFR CIGS AND VSBYS LIKELY IN SHRA AND SCT
TSRA.
THU...PRIMARILY VFR. SCT SHRA/TSRA POSS MAINLY SE.
FRI...PRIMARILY VFR. ISOLD SHRA/TSRA POSS MAINLY SE.
SAT...VFR. A CHC OF A SHRA OR TSRA ACROSS THE NORTH.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...DEVOIR/MARTIN
NEAR TERM...DEVOIR/MARTIN
SHORT TERM...DEVOIR/FITZGERALD/MARTIN
LONG TERM...MARTIN
AVIATION...JUNG

000
FXUS61 KPHI 212323
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
723 PM EDT MON MAY 21 2012

.SYNOPSIS...
A LOW PRESSURE SYSTEM OFF THE MIDDLE ATLANTIC COAST IS FORECAST TO
DRIFT SLOWLY NORTHEAST AND REACH THE CANADIAN MARITIMES ON
WEDNESDAY. THEREAFTER AN ATLANTIC HIGH PRESSURE SYSTEM WILL BUILD
WEST AND PERSIST INTO THE START OF THE MEMORIAL DAY WEEKEND. A
BACKDOOR COLD FRONT FROM EASTERN CANADA IS THEN FORECAST TO APPROACH
AND STALL NEAR THE REGION ON SUNDAY AND MONDAY.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
THE MAIN FORECAST PROBLEM FOR THE OVERNIGHT WILL BE THE COVERAGE OF
SHOWERS...ESPECIALLY ACROSS EASTERN SECTIONS.

THE TRAIN OF SHOWERS THAT EXTENDED FROM EAST OF THE VIRGINIA COAST
INTO SOUTHEAST NEW YORK STATE IS STILL MORE OR LESS IN PLACE. THERE
APPEARS TO BE ANOTHER AREAS OF MORE CONVECTIVE LOOKING SHOWERS
APPROACHING SOUTHERNMOST NEW JERSEY EARLY THIS EVENING. THE TRAIN IS
LODGED IN AN AXIS OF HIGH PRECIPITABLE WATER (LATEST ANALYSIS SHOWS
PRECIPITABLE WATER VALUES NEAR 1.60 INCHES).

THERE HAS BEEN SOME LIGHTNING ON THE SOUTHERN EDGE OF THE TRAIN EAST
OF THE VIRGINIA COAST...BUT THE WARM CORE PROCESSES THIS FAR NORTH
ARE NOT PRODUCING ENOUGH CHARGE SEPARATION FOR LIGHTNING. NEAR AND
SHORT TERM MODELS ARE SHOWING SOME SPREAD ON JUST HOW MUCH OF THE
ACTIVITY TO THE SOUTH GETS INTO NEW JERSEY LATER THIS EVENING. HEAVY
RAIN EARLIER TODAY PRODUCED 1 TO 2 INCHES OF RAIN ACROSS PORTIONS OF
NORTH CENTRAL NEW JERSEY...AS WELL AS THE MONMOUTH COUNTY COAST.

AT THIS POINT...IT DOES NOT APPEAR AS THOUGH THE ADDITIONAL RAIN
WOULD HIT THE ABOVEMENTIONED AREAS HARD AGAIN THIS EVENING. MOST
AREAS SHOULD BE ABLE TO ABSORB THE ADDITIONAL RAINFALL WITH LOCAL
NUISANCE FLOODING EXPECTED.

A HOLE IN THE OVERCAST HAS MOVED INTO DELAWARE AND NORTHEAST
MARYLAND. THE AIRMASS HAS RESPONDED BY BECOMING MARGINALLY UNSTABLE.
HOWEVER...THE INSTABILITY HAS NO FOCUS OR UPSTREAM MEANS FOR
RELEASE...SO AT THIS POINT...THE MENTION OF THUNDER WILL BE REMOVED
FROM THE FORECAST. THE AREA OF CLEARING SHOULD FILL BACK IN AS LOWER
CLOUDS FORM AGAIN IN THE MOISTENING LOW LEVEL FLOW.

DEW POINTS HAVE CLIMBED INTO THE 60S ACROSS THE AREA. WITH LITTLE
CHANGE IN THE AIRMASS OVERNIGHT...THE DEW POINTS SHOULD ACT AS A
LOWER END OF THE RANGE FOR LOWS. THIS IS MORE OR LESS WHAT MOS
VALUES ARE SHOWING FOR LOWS...AND A BLEND OF THOSE NUMBERS IS
ACCEPTED. THE BOUNDARY LAYER DOES NOT APPEAR AS THOUGH IT WILL
SATURATE OVERNIGHT...SO FOR NOW THE FOG WAS NOT HIT THAT HARD.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/...
NOT MUCH CHANGE IN THE OVERALL TRENDS TOMORROW, EVEN THOUGH THE MDL
SOLNS AGAIN DIFFER ON HOW WET WE WILL BE.  THIS IS MAINLY DUE TO THE
FACT THAT ANY PRECIP WILL BE DEPENDENT ON THESE WAVES ON ELY FLOW
THAT HAVE BEEN DIFFICULT TO FORECAST MORE THAN A FEW HOURS IN
ADVANCE.  SO WHILE ALL MDLS FCST IT TO BE WARMER, THE MOST
OPTIMISTIC MDLS HAVE IT LESS DREARY AND THE MOST PESSIMISTIC...WELL
NOT SO MUCH...

ONCE AGAIN ANY PRECIP WAVES COULD PRODUCE LOCALLY HEAVY RAINFALL AS
THEY WILL BE SLOW MOVING, BUT OVERALL QPF WILL BE LIGHT.

&&

.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
ITS GOING TO BE A SLOW RECOVERY FROM PRECIPITATION CHANCES AS THE
LONG TERM PROGRESSES WITH SOME UNSEASONABLY WARM WEATHER EXPECTED
OVER THE MEMORIAL DAY WEEKEND. THE LAZY FLOW ALOFT IS MORE TYPICAL
OF LATE AUGUST THAN LATE MAY AND AS SUCH THE SLOW MOVING CONVECTION
WILL PRODUCE SOME LOCALLY HEAVY DOWNPOURS. CONVECTION SHOULD BE
DIURNALLY DRIVEN AND THERE WILL BE A TRAIL OFF IN THE POPS AT
NIGHT.

SO BEGINNING WITH TUESDAY NIGHT CONVECTIVE COVERAGE AND CHANCES WILL
LOWER AS THE NIGHT PROGRESSES. WE DROP THE MENTION OF THUNDER AFTER
THE EVENING. FORECAST SOUNDINGS SUGGEST EITHER LOW CLOUDS AND OR FOG
WILL FORM. FOR NOW WE KEPT THE MENTION OF PATCHY FOG AS CONFIDENCE
ABOUT ONE OVER THE OTHER IS NOT HIGH ENOUGH TO MAKE A CHOICE OR CHANGE.
STAT GUIDANCE WAS CLOSE AND ACCEPTED.

THE CLOSED LOW ACROSS THE SERN CONUS IS FORECAST TO COME CLOSER ON
WEDNESDAY DAY. WITH CONVECTIVE TEMPS FORECAST TO BE IN THE MID 70S
WITH SOME DPVA AND OMEGA FORECAST ESPECIALLY SOUTHWEST. WE UPPED
THE POPS TO LIKELY BY LATE AFTERNOON PRETTY MUCH FROM THE LEHIGH
AND DELAWARE VALLEY SOUTHWESTWARD. MODELS ARE ALSO HINTING AND
SOME CONVERGENCE FROM DIFFERENT BAY BREEZES ON THE DELMARVA
PENINSULA. DIFFERENCES AS TO FORECAST INSTAB, BUT THE OVERALL WIND
FIELD IS FORECAST TO BE VERY WEAK AND NOT MUCH OF A DROP OFF OF
THETA E WITH HEIGHT IN THE MID LEVELS. SO MAIN CONCERN LOOKS LIKE
LOCALLY HEAVY RAIN. GIVEN THE FORECAST CONVECTIVE TEMPS, STAT
GUIDANCE LOOKS REASONABLE.

WE THROTTLE DOWN THE PRECIPITATION CHANCES AGAIN ON WEDNESDAY NIGHT.
ON THURSDAY A HIGH PRESSURE SYSTEM FROM JAMES BAY IS FORECAST TO
BUILD OVER THE NEW ENGLAND COASTAL WATERS. ITS TRACK IS A BIT
FARTHER TO THE EAST THAN SOME OF THE DIRTY HIGHS WE HAVE HAD THIS
SPRING. NEVERTHELESS IT GIVES US PAUSE AS TO HOW WARM A DAY THURSDAY
WILL BE AND HOW MANY LOW CLOUDS WILL COME IN OFF THE OCEAN. AS FAR
AS POPS GO, THINKING GFS EASTWARD EMPHASIS MAY BE GIVING THE HIGH
TOO LITTLE CREDIT, SO WE LEANED HIGHEST POPS FARTHER TO THE WEST.

THE 500MB TROF IS STILL LINGERING INTO THURSDAY NIGHT AND FRIDAY, SO
WE MAINTAIN SOME CHANCES. THE MARINE INFLUENCE ON FRIDAY BY THE
SURFACE HIGH APPEARS LESS, SO WE WENT ALONG WITH A COMPROMISE
BETWEEN GFS AND EURO MOS FOR MAX TEMPS.

THEN FOR MEMORIAL DAY WEEKEND PRETTY MUCH THE GIRL WITH THE CURL
TYPE WEEKEND IT SEEMS FOR US, EITHER VERY GOOD OR VERY BAD, SELDOM
IN THE MIDDLE. THIS TIME THE MODELS ARE CONTINUING TO OUTLOOK WHAT
WOULD BE A "SUMMER" TIME WEEKEND. THERE IS PRETTY MUCH GOOD
AGREEMENT ABOUT A WARM DAY FOR SATURDAY WITH RELATIVELY SPEAKING
OUR LOWEST CHANCES FOR PRECIPITATION. AFTER THAT THERE REMAINS
DIFFERENCES AS TO HOW MUCH CAN A BACKDOOR FRONT SLIP TOWARD OR
INTO OUR CWA ON SUNDAY OR MONDAY. THE GFS HAS BEEN MORE
AGGRESSIVE. THE 12Z EURO HAS TRENDED THE GFS`S WAY BUT MORE IN A
YOU WON THE BATTLE BUT NOT NECESSARILY THE TEMPERATURE WAR. WE
HAVE SOME SLIGHT CHANCES IN BECAUSE OF THE PROXIMITY TO THE FRONT.
FOR NOW WE ARE BANKING ON NOT MUCH OF A THERMAL EFFECT FROM THE
FRONT WITH MAX TEMPS PROGGED MUCH CLOSER TO EC MOS THAN GFS MOS.

&&

.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.

THE BREAK IN THE CLOUDS OVER DELAWARE AND NORTHEAST MARYLAND NOT
WITHSTANDING...MVFR AND IFR CONDITIONS WILL TRANSITION TO LIFR
CONDITIONS OVERNIGHT. THE QUESTION BECOMES JUST HOW QUICKLY.

PATCHY LIGHT RAIN AND DRIZZLE WILL CONTINUE ACROSS THE REGION DURING
THE NEXT FEW HOURS. THE LIGHT RAIN WILL HELP TO SATURATE THE LOW
LEVELS...AND AID THE TRANSITION TO LIFR. RIGHT NOW...IT WOULD APPEAR
TO ALL LOCATIONS WILL DROP TO LIFR BY 0400 UTC...AND STAY THERE
THROUGH AT LEAST 1300 UTC. THE STATISTICAL GUIDANCE SUGGESTS THAT
THE LOWER LEVELS COULD MOISTEN ENOUGH FOR 1/2SM IN FOG AT KACY AND
KMIV BETWEEN 0800 UTC AND 1300 UTC.

THE TRANSITION FROM LIFR THROUGH IFR TO MVFR SHOULD OCCUR BETWEEN
1300 UTC AND 1600 UTC...OCCURRING FIRST AT KRDG AND KABE...AND LAST
AT KACY. THE BOUNDARY LAYER COULD WARM ENOUGH FOR SOME LOCATIONS TO
REACH VFR FOR A TIME AT THE KPHL METRO AIRPORTS TUESDAY AFTERNOON.
BREAKS COULD ALLOW FOR SCATTERED THUNDERSTORMS...BUT THE CONFIDENCE
SIMPLY IS NOT THERE TO INCLUDE IN THE FORECAST YET.

OUTLOOK...
TUESDAY NIGHT THROUGH FRIDAY...MVFR OR IFR CONDS LATER EACH NIGHT
AND EARLY EACH DAY IN STRATUS OR FOG BECOMING VFR MIDDAY INTO THE
EVENING. LOCAL MVFR OR IFR CONDS IN SHOWERS OR TSTMS. OUTLOOKING
LESS COVERAGE AND DURATION OF IFR AND MVFR CONDITIONS ON FRIDAY.

SATURDAY...POSSIBLY SOME MVFR EARLY, OTHERWISE VFR.

&&

.MARINE...
THE PROLONGED ELY TO EVENTUALLY SELY FLOW WILL CONTINUE AND THE SCA
REMAINS IN PLACE.  WE OPTED TO CONVERT IT TO A SCA FOR HIGH SEAS AS
WE DON`T BELIEVE WINDS WILL PROLONGED BE A SIGNIFICANT FACTOR
OUTSIDE OF ANY SHOWERS OR TSTMS.  SO FAR THIS AFTN, SEAS HAVE
REMAINED BELOW CRITERIA, BUT WITH A LARGE AREA OF PRECIP OFF THE
COAST AND RADAR SHOWING ENHANCEMENT, EXPECT THINGS TO PICK UP.

OUTLOOK...
WE ARE EXPECTING SMALL CRAFT ADVISORY CONDITIONS FROM SEAS TO
PERSIST INTO TUESDAY NIGHT. AFTER THAT WE ARE NOT OUTLOOKING SMALL
CRAFT ADVISORY CONDITIONS TO BE MET THROUGH THE REST OF THE
DETERMINISTIC FORECAST. THE ONSHORE GRADIENT AND SWELLS FROM THE
HIGH BUILDING ACROSS THE CANADIAN MARITIMES IS NOT EXPECTED TO BE
STRONG ENOUGH TO GENERATE SMALL CRAFT CONDITIONS CENTERED AROUND
THURSDAY. AFTER THAT THE HIGH BUILDS FARTHER INTO OUR MARINE AREA
REDUCING THE THREAT OF SMALL CRAFT CONDITIONS EVEN FURTHER. THE
APPROACHING BACK DOOR FRONT SHOULD NOT BE AN ISSUE, IF EVER AT ALL,
THROUGH SATURDAY.

&&

.HYDROLOGY...
OCCASIONAL INSTABILITY IN ASSOCIATION WITH PERSISTENTLY HIGH HUMIDITY
AND COOL TROUGHING ALOFT WILL YIELD SOME LOCALLY HEAVY DOWNPOURS.
MOST OF THE AREA SHOULD RECEIVE HALF AN INCH THIS WEEK...INCLUDING
AMOUNTS THAT BEGAN THIS PAST SUNDAY EVENING. IF THERE WERE TO BE ANY
SMALL STREAM FLOOD PROBLEMS...IT WOULD MORE LIKELY OCCUR IN EASTERN
PENNSYLVANIA OR NORTHERN NEW JERSEY WHERE GRIDDED FLASH FLOOD
GUIDANCE SHOWS GREATER VULNERABILITY. 1 HR FFG NEAR 1.3 INCHES AND 6
TO 24 HR GUIDANCE IS CURRENTLY NEAR 1.9 INCHES. THAT WOULD PLACE
MONTGOMERY...WITH THE NEARBY CHESTER COUNTY PA BORDER AND CENTRAL
MORRIS COUNTY NJ AS SEEMINGLY MOST VULNERABLE.

&&

.RIP CURRENTS...
SWELL HEIGHTS NEAR 5 FEET...COMBINED WITH A DOMINANT 9 SECOND
PERIOD...WILL OUTWEIGH THE SLACKENING PRESSURE GRADIENT TUESDAY.
THE COMBINATION OF THE SWELL HEIGHT AND RELATIVELY LONG PERIOD
WILL RESULT IN A MODERATE RISK OF RIP CURRENTS TUESDAY. WHILE THE
COMBINATION SHOULD HAVE A LESSER EFFECT ON THE DELAWARE
BEACHES...IT WAS INCLUDED IN THE MODERATE RISK.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 AM EDT
     WEDNESDAY FOR ANZ450>455.

&&

$$

SYNOPSIS...GIGI
NEAR TERM...HAYES
SHORT TERM...NIERENBERG
LONG TERM...GIGI
AVIATION...GIGI/HAYES
MARINE...GIGI/NIERENBERG
HYDROLOGY...GIGI
RIP CURRENTS...HAYES

000
FXUS61 KPBZ 212235
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
635 PM EDT MON MAY 21 2012

.SYNOPSIS...
RAIN CHANCES WILL BE ON THE INCREASE THROUGH TUESDAY AS A COLD
FRONT SLOWLY APPROACHES FROM THE WEST AND AS LOW PRESSURE MOVES UP
THE EAST COAST.

&&

.NEAR TERM /THROUGH TUESDAY/...
AN EARLY EVENING UPDATE HAS BEEN ISSUED TO ACCOUNT FOR THE LATEST
TRENDS IN RADAR AND SKY COVERAGE.

RAP MID-LEVEL ANALYSIS A BROAD MID-LEVEL TROUGH EXTENDING ACROSS
THE OHIO VALLEY. MSAS SURFACE ANALYSIS INDICATES A WEAK LOW
CENTERED ACROSS CENTRAL OHIO WITH A NORTH- SOUTH ORIENTED FRONTAL
BOUNDARY BISECTING THE STATE. A POCKET OF DEW POINTS IN THE LOWER
50S IS LOCATED IN EASTERN OHIO. SKIES REMAIN CLEAR IN THIS POCKET
WITH SCATTERED SHOWERS AND THUNDERSTORMS DEVELOPING IN LOCATIONS
TO THE EAST AND WEST WHERE TDS ARE IN THE UPPER 50S TO LOWER 60S.
POCKETS OF MODERATE INSTABILITY LOCATED WITH LITTLE OR WIND SHEAR
HAVE ALLOWED FOR VERY SLOW MOVING SHOWERS AND THUNDERSTORMS WITH
HEAVY DOWNPOURS THIS EVENING IN WESTERN PA AND NORTH-CENTRAL WV.

THIS EVENING AND TONIGHT...THE BROAD MID-LEVEL TROUGH WILL
CONTINUE TO MOVE SLOWLY ACROSS THE OHIO VALLEY. MODERATE INSTABILITY
WILL FUEL CONVECTION EARLY WITH WEAK WINDS ALOFT ALLOWING FOR
SHOWERS AND THUNDERSTORMS TO HAVE VERY LITTLE MOVEMENT. SCATTERED
COVERAGE WILL BECOME MORE ISOLATED WITH THE LOSS OF HEATING AND
INHERENT INSTABILITY TONIGHT. THE POTENTIAL OF LOCALLY HEAVY
RAINFALL LEADING TO MINOR FLOODING HAS BEEN MENTIONED THE HWO.

OVERNIGHT LOWS WILL REMAIN RELATIVELY WARM AS INCREASED BOUNDARY
LAYER MOISTURE WILL PRECLUDE A DRAMATIC DROP. TEMPERATURES ARE
FAIRLY CLOSE TO LAMP GUIDANCE OVERNIGHT, WITH LOWS IN RANGING FROM
THE MID 50S ACROSS THE EASTERN RIDGES TO THE LOWER 60S IN PORTIONS
OF EASTERN OHIO.

&&

.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
PROGRESS OF THE FRONT WILL BE SLOW GIVEN THE AFOREMENTIONED WEAKNESS
OF THE OVERALL WIND FIELD. WITH PERSISTENT UPPER/MID LEVEL TROUGH FORECAST
OVER THE EASTERN CONUS...EXPECT CONVECTIVE TEMPERATURES TO REMAIN SUFFICIENTLY
LOW FOR DIURNALLY SUPPORTED SHOWER AND THUNDERSTORM DEVELOPMENT WITH
FOCUS VIA THE FRONT...RIDGES...OR OUTFLOW BOUNDARIES. WILL THUS FORECAST
LIKELY POPS ON TUESDAY WITH PASSAGE OF THE FRONT...FOLLOWED BY SCATTERED
PRECIP POTENTIAL THROUGH THE REMAINDER OF THE SHORT TERM.

WARM...HUMID CONDITIONS CAN BE EXPECTED TO CONTINUE THROUGH THE PERIOD.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
UPPER TROUGH MOVING OFF TO THE EAST WILL STILL SPAWN ISOLATED
SHOWERS/THUNDERSTORMS FRIDAY. AFTER THAT...UPPER RIDGE WILL BUILD
INTO THE REGION AND REMAIN NEARLY STATIONARY. ISOLATED
SHOWERS/THUNDERSTORMS CANNOT BE RULED OUT AS A WEAK SURFACE FRONT
TRIES TO MOVE THROUGH. TEMPERATURES SHOULD BE WELL ABOVE
NORMAL...WITH UPPER 80S AND LOWER 90S EXPECTED FOR THE HOLIDAY
WEEKEND.

&&

.AVIATION /22Z MONDAY THROUGH SATURDAY/...
CLOUDS WILL CONTINUE TO INCREASE FROM EAST TO WEST AS LOW PRESSURE
MOVES IN FROM THE ATLANTIC OCEAN. IN ADDITION...A FRONT WILL
CROSS THE REGION VERY SLOWLY TONIGHT INTO TUESDAY. ISOLATED
SHOWERS WILL SLOWLY INCREASE IN COVERAGE...BUT WITH NO FOCUSING
MECHANISM TO PINPOINT A LOCATION...WILL NOT INCLUDE SHOWERS IN THE
TAFS AT THIS TIME. AN ISOLATED THUNDERSTORM CANNOT BE RULED OUT
EITHER. EASTERLY FLOW WILL ALLOW FOR ADDITIONAL LOW-LEVEL MOISTURE
TO MOVE IN AFTER MIDNIGHT...AND HAVE DROPPED ALL TAFS (EXCEPT ZZV)
TO IFR CONDITIONS IN FOG/STRATUS. CATEGORIES SHOULD RISE BACK TO
MVFR BY LATE TUESDAY MORNING.

.OUTLOOK...TUESDAY THROUGH SATURDAY...
SCATTERED SHOWERS ARE POSSIBLE THROUGH THURSDAY...WITH DIURNAL
CYCLE BRINGING GREATER COVERAGE DURING THE DAYTIME HOURS THAN
NIGHTTIME HOURS. AS THE FRONT MOVES THROUGH TUESDAY
AFTERNOON...SHOWERS APPEAR LIKELY FROM PITTSBURGH EAST FOR THIS
TIME PERIOD. SURFACE DEW POINTS WILL INCREASE THROUGH THE PERIOD
AND WILL LIKELY RESULT IN MVFR VISIBILITY RESTRICTIONS AT MOST
AIRPORT LOCATIONS DURING THE EARLY MORNING HOURS THROUGH THURSDAY.
COVERAGE OF SHOWERS SHOULD BE ISOLATED FOR FRIDAY AND SATURDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$

000
FXUS61 KPHI 212220
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
620 PM EDT MON MAY 21 2012

.SYNOPSIS...
A LOW PRESSURE SYSTEM OFF THE MIDDLE ATLANTIC COAST IS FORECAST TO
DRIFT SLOWLY NORTHEAST AND REACH THE CANADIAN MARITIMES ON
WEDNESDAY. THEREAFTER AN ATLANTIC HIGH PRESSURE SYSTEM WILL BUILD
WEST AND PERSIST INTO THE START OF THE MEMORIAL DAY WEEKEND. A
BACKDOOR COLD FRONT FROM EASTERN CANADA IS THEN FORECAST TO APPROACH
AND STALL NEAR THE REGION ON SUNDAY AND MONDAY.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
THE MAIN FORECAST PROBLEM FOR THE OVERNIGHT WILL BE THE COVERAGE OF
SHOWERS...ESPECIALLY ACROSS EASTERN SECTIONS.

THE TRAIN OF SHOWERS THAT EXTENDED FROM EAST OF THE VIRGINIA COAST
INTO SOUTHEAST NEW YORK STATE IS STILL MORE OR LESS IN PLACE. THERE
APPEARS TO BE ANOTHER AREAS OF MORE CONVECTIVE LOOKING SHOWERS
APPROACHING SOUTHERNMOST NEW JERSEY EARLY THIS EVENING. THE TRAIN IS
LODGED IN AN AXIS OF HIGH PRECIPITABLE WATER (LATEST ANALYSIS SHOWS
PRECIPITABLE WATER VALUES NEAR 1.60 INCHES).

THERE HAS BEEN SOME LIGHTNING ON THE SOUTHERN EDGE OF THE TRAIN EAST
OF THE VIRGINIA COAST...BUT THE WARM CORE PROCESSES THIS FAR NORTH
ARE NOT PRODUCING ENOUGH CHARGE SEPARATION FOR LIGHTNING. NEAR AND
SHORT TERM MODELS ARE SHOWING SOME SPREAD ON JUST HOW MUCH OF THE
ACTIVITY TO THE SOUTH GETS INTO NEW JERSEY LATER THIS EVENING. HEAVY
RAIN EARLIER TODAY PRODUCED 1 TO 2 INCHES OF RAIN ACROSS PORTIONS OF
NORTH CENTRAL NEW JERSEY...AS WELL AS THE MONMOUTH COUNTY COAST.

AT THIS POINT...IT DOES NOT APPEAR AS THOUGH THE ADDITIONAL RAIN
WOULD HIT THE ABOVEMENTIONED AREAS HARD AGAIN THIS EVENING. MOST
AREAS SHOULD BE ABLE TO ABSORB THE ADDITIONAL RAINFALL WITH LOCAL
NUISANCE FLOODING EXPECTED.

A HOLE IN THE OVERCAST HAS MOVED INTO DELAWARE AND NORTHEAST
MARYLAND. THE AIRMASS HAS RESPONDED BY BECOMING MARGINALLY UNSTABLE.
HOWEVER...THE INSTABILITY HAS NO FOCUS OR UPSTREAM MEANS FOR
RELEASE...SO AT THIS POINT...THE MENTION OF THUNDER WILL BE REMOVED
FROM THE FORECAST. THE AREA OF CLEARING SHOULD FILL BACK IN AS LOWER
CLOUDS FORM AGAIN IN THE MOISTENING LOW LEVEL FLOW.

DEW POINTS HAVE CLIMBED INTO THE 60S ACROSS THE AREA. WITH LITTLE
CHANGE IN THE AIRMASS OVERNIGHT...THE DEW POINTS SHOULD ACT AS A
LOWER END OF THE RANGE FOR LOWS. THIS IS MORE OR LESS WHAT MOS
VALUES ARE SHOWING FOR LOWS...AND A BLEND OF THOSE NUMBERS IS
ACCEPTED. THE BOUNDARY LAYER DOES NOT APPEAR AS THOUGH IT WILL
SATURATE OVERNIGHT...SO FOR NOW THE FOG WAS NOT HIT THAT HARD.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/...
NOT MUCH CHANGE IN THE OVERALL TRENDS TOMORROW, EVEN THOUGH THE MDL
SOLNS AGAIN DIFFER ON HOW WET WE WILL BE.  THIS IS MAINLY DUE TO THE
FACT THAT ANY PRECIP WILL BE DEPENDENT ON THESE WAVES ON ELY FLOW
THAT HAVE BEEN DIFFICULT TO FORECAST MORE THAN A FEW HOURS IN
ADVANCE.  SO WHILE ALL MDLS FCST IT TO BE WARMER, THE MOST
OPTIMISTIC MDLS HAVE IT LESS DREARY AND THE MOST PESSIMISTIC...WELL
NOT SO MUCH...

ONCE AGAIN ANY PRECIP WAVES COULD PRODUCE LOCALLY HEAVY RAINFALL AS
THEY WILL BE SLOW MOVING, BUT OVERALL QPF WILL BE LIGHT.

&&

.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
ITS GOING TO BE A SLOW RECOVERY FROM PRECIPITATION CHANCES AS THE
LONG TERM PROGRESSES WITH SOME UNSEASONABLY WARM WEATHER EXPECTED
OVER THE MEMORIAL DAY WEEKEND. THE LAZY FLOW ALOFT IS MORE TYPICAL
OF LATE AUGUST THAN LATE MAY AND AS SUCH THE SLOW MOVING CONVECTION
WILL PRODUCE SOME LOCALLY HEAVY DOWNPOURS. CONVECTION SHOULD BE
DIURNALLY DRIVEN AND THERE WILL BE A TRAIL OFF IN THE POPS AT
NIGHT.

SO BEGINNING WITH TUESDAY NIGHT CONVECTIVE COVERAGE AND CHANCES WILL
LOWER AS THE NIGHT PROGRESSES. WE DROP THE MENTION OF THUNDER AFTER
THE EVENING. FORECAST SOUNDINGS SUGGEST EITHER LOW CLOUDS AND OR FOG
WILL FORM. FOR NOW WE KEPT THE MENTION OF PATCHY FOG AS CONFIDENCE
ABOUT ONE OVER THE OTHER IS NOT HIGH ENOUGH TO MAKE A CHOICE OR CHANGE.
STAT GUIDANCE WAS CLOSE AND ACCEPTED.

THE CLOSED LOW ACROSS THE SERN CONUS IS FORECAST TO COME CLOSER ON
WEDNESDAY DAY. WITH CONVECTIVE TEMPS FORECAST TO BE IN THE MID 70S
WITH SOME DPVA AND OMEGA FORECAST ESPECIALLY SOUTHWEST. WE UPPED
THE POPS TO LIKELY BY LATE AFTERNOON PRETTY MUCH FROM THE LEHIGH
AND DELAWARE VALLEY SOUTHWESTWARD. MODELS ARE ALSO HINTING AND
SOME CONVERGENCE FROM DIFFERENT BAY BREEZES ON THE DELMARVA
PENINSULA. DIFFERENCES AS TO FORECAST INSTAB, BUT THE OVERALL WIND
FIELD IS FORECAST TO BE VERY WEAK AND NOT MUCH OF A DROP OFF OF
THETA E WITH HEIGHT IN THE MID LEVELS. SO MAIN CONCERN LOOKS LIKE
LOCALLY HEAVY RAIN. GIVEN THE FORECAST CONVECTIVE TEMPS, STAT
GUIDANCE LOOKS REASONABLE.

WE THROTTLE DOWN THE PRECIPITATION CHANCES AGAIN ON WEDNESDAY NIGHT.
ON THURSDAY A HIGH PRESSURE SYSTEM FROM JAMES BAY IS FORECAST TO
BUILD OVER THE NEW ENGLAND COASTAL WATERS. ITS TRACK IS A BIT
FARTHER TO THE EAST THAN SOME OF THE DIRTY HIGHS WE HAVE HAD THIS
SPRING. NEVERTHELESS IT GIVES US PAUSE AS TO HOW WARM A DAY THURSDAY
WILL BE AND HOW MANY LOW CLOUDS WILL COME IN OFF THE OCEAN. AS FAR
AS POPS GO, THINKING GFS EASTWARD EMPHASIS MAY BE GIVING THE HIGH
TOO LITTLE CREDIT, SO WE LEANED HIGHEST POPS FARTHER TO THE WEST.

THE 500MB TROF IS STILL LINGERING INTO THURSDAY NIGHT AND FRIDAY, SO
WE MAINTAIN SOME CHANCES. THE MARINE INFLUENCE ON FRIDAY BY THE
SURFACE HIGH APPEARS LESS, SO WE WENT ALONG WITH A COMPROMISE
BETWEEN GFS AND EURO MOS FOR MAX TEMPS.

THEN FOR MEMORIAL DAY WEEKEND PRETTY MUCH THE GIRL WITH THE CURL
TYPE WEEKEND IT SEEMS FOR US, EITHER VERY GOOD OR VERY BAD, SELDOM
IN THE MIDDLE. THIS TIME THE MODELS ARE CONTINUING TO OUTLOOK WHAT
WOULD BE A "SUMMER" TIME WEEKEND. THERE IS PRETTY MUCH GOOD
AGREEMENT ABOUT A WARM DAY FOR SATURDAY WITH RELATIVELY SPEAKING
OUR LOWEST CHANCES FOR PRECIPITATION. AFTER THAT THERE REMAINS
DIFFERENCES AS TO HOW MUCH CAN A BACKDOOR FRONT SLIP TOWARD OR
INTO OUR CWA ON SUNDAY OR MONDAY. THE GFS HAS BEEN MORE
AGGRESSIVE. THE 12Z EURO HAS TRENDED THE GFS`S WAY BUT MORE IN A
YOU WON THE BATTLE BUT NOT NECESSARILY THE TEMPERATURE WAR. WE
HAVE SOME SLIGHT CHANCES IN BECAUSE OF THE PROXIMITY TO THE FRONT.
FOR NOW WE ARE BANKING ON NOT MUCH OF A THERMAL EFFECT FROM THE
FRONT WITH MAX TEMPS PROGGED MUCH CLOSER TO EC MOS THAN GFS MOS.

&&

.AVIATION /22Z MONDAY THROUGH SATURDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.

CONDS ACRS THE REGION RANGED FROM MVFR TO IFR WITH CLOUD COVER AND
SOME SHOWERS.  A LARGER AREA OF PRECIP LOOKS LIKE IT IS "FINALLY"
TRYING TO MOVE ONSHORE OVER S JERSEY.  THINGS IMPROVED FASTER THAN
EXPECTED THIS AFTN AND EXPECT THESE IMPROVEMENTS TO STAY OUTSIDE OF
ANY LOCAL SHOWERS THRU EARLY EVENING, WHEN A RETURN TO A MORE
GENERAL IFR AND EVENTUAL LIFR IN SOME AREAS IS ANTICIPATED
OVERNIGHT.

OVERALL, STILL NOT THE BEST PD TO BE FLYING.

OUTLOOK...
TUESDAY NIGHT THROUGH FRIDAY...MVFR OR IFR CONDS LATER EACH NIGHT
AND EARLY EACH DAY IN STRATUS OR FOG BECOMING VFR MIDDAY INTO THE
EVENING. LOCAL MVFR OR IFR CONDS IN SHOWERS OR TSTMS. OUTLOOKING
LESS COVERAGE AND DURATION OF IFR AND MVFR CONDITIONS ON FRIDAY.

SATURDAY...POSSIBLY SOME MVFR EARLY, OTHERWISE VFR.

&&

.MARINE...
THE PROLONGED ELY TO EVENTUALLY SELY FLOW WILL CONTINUE AND THE SCA
REMAINS IN PLACE.  WE OPTED TO CONVERT IT TO A SCA FOR HIGH SEAS AS
WE DON`T BELIEVE WINDS WILL PROLONGED BE A SIGNIFICANT FACTOR
OUTSIDE OF ANY SHOWERS OR TSTMS.  SO FAR THIS AFTN, SEAS HAVE
REMAINED BELOW CRITERIA, BUT WITH A LARGE AREA OF PRECIP OFF THE
COAST AND RADAR SHOWING ENHANCEMENT, EXPECT THINGS TO PICK UP.

OUTLOOK...
WE ARE EXPECTING SMALL CRAFT ADVISORY CONDITIONS FROM SEAS TO
PERSIST INTO TUESDAY NIGHT. AFTER THAT WE ARE NOT OUTLOOKING SMALL
CRAFT ADVISORY CONDITIONS TO BE MET THROUGH THE REST OF THE
DETERMINISTIC FORECAST. THE ONSHORE GRADIENT AND SWELLS FROM THE
HIGH BUILDING ACROSS THE CANADIAN MARITIMES IS NOT EXPECTED TO BE
STRONG ENOUGH TO GENERATE SMALL CRAFT CONDITIONS CENTERED AROUND
THURSDAY. AFTER THAT THE HIGH BUILDS FARTHER INTO OUR MARINE AREA
REDUCING THE THREAT OF SMALL CRAFT CONDITIONS EVEN FURTHER. THE
APPROACHING BACK DOOR FRONT SHOULD NOT BE AN ISSUE, IF EVER AT ALL,
THROUGH SATURDAY.

&&

.HYDROLOGY...
OCCASIONAL INSTABILITY IN ASSOCIATION WITH PERSISTENTLY HIGH HUMIDITY
AND COOL TROUGHING ALOFT WILL YIELD SOME LOCALLY HEAVY DOWNPOURS.
MOST OF THE AREA SHOULD RECEIVE HALF AN INCH THIS WEEK...INCLUDING
AMOUNTS THAT BEGAN THIS PAST SUNDAY EVENING. IF THERE WERE TO BE ANY
SMALL STREAM FLOOD PROBLEMS...IT WOULD MORE LIKELY OCCUR IN EASTERN
PENNSYLVANIA OR NORTHERN NEW JERSEY WHERE GRIDDED FLASH FLOOD
GUIDANCE SHOWS GREATER VULNERABILITY. 1 HR FFG NEAR 1.3 INCHES AND 6
TO 24 HR GUIDANCE IS CURRENTLY NEAR 1.9 INCHES. THAT WOULD PLACE
MONTGOMERY...WITH THE NEARBY CHESTER COUNTY PA BORDER AND CENTRAL
MORRIS COUNTY NJ AS SEEMINGLY MOST VULNERABLE.

&&

.RIP CURRENTS...
SWELL HEIGHTS NEAR 5 FEET...COMBINED WITH A DOMINANT 9 SECOND
PERIOD...WILL OUTWEIGH THE SLACKENING PRESSURE GRADIENT TUESDAY.
THE COMBINATION OF THE SWELL HEIGHT AND RELATIVELY LONG PERIOD
WILL RESULT IN A MODERATE RISK OF RIP CURRENTS TUESDAY. WHILE THE
COMBINATION SHOULD HAVE A LESSER EFFECT ON THE DELAWARE
BEACHES...IT WAS INCLUDED IN THE MODERATE RISK.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 AM EDT
     WEDNESDAY FOR ANZ450>455.

&&

$$

SYNOPSIS...GIGI
NEAR TERM...HAYES
SHORT TERM...NIERENBERG
LONG TERM...GIGI
AVIATION...GIGI/NIERENBERG
MARINE...GIGI/NIERENBERG
HYDROLOGY...GIGI
RIP CURRENTS...HAYES

000
FXUS61 KCTP 211952
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
352 PM EDT MON MAY 21 2012

.SYNOPSIS...
AN UPPER LOW OVER THE SOUTHEAST COAST WILL OPEN UP AND LIFT
TONIGHT. A DEEPENING SHORTWAVE WILL SLOW DOWN AND CUT OFF OVR THE
CENTRAL APPALACHIANS DURING THE MIDDLE OF THE WEEK. PENNSYLVANIA
WILL BE ON THE EDGE OF THE REBUILDING UPPER RIDGE ACROSS THE OHIO
VALLEY BY THE END OF WEEK. THIS BUILDING RIDGE WILL KEEP WARM
TEMPERATURES ACROSS THE REGION INTO THE HOLIDAY WEEKEND.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
UPPER LOW OVER THE CAROLINA COAST WILL LIFT NORTH ALONG THE E
COAST DURING THE NEXT 24HRS. MOIST...EASTERLY LL JET AND UPPER
LVL DIVERGENCE PRECEDING THE UPPER LOW WILL BRING SHOWERS TO MOST
OF CENTRAL PA THROUGH TONIGHT. CIRCULATION AROUND BROAD UPPER LOW
OVER THE SOUTHEASTERN UNITED STATES AND WESTERN ATLANTIC AND SFC
HIGH TO THE EAST OF NEW ENGLAND IS DIRECTING HIGHER PW AIR INTO
SOUTHEAST AND CENTRAL PA THIS AFT...COINCIDING WITH MARITIME
EASTERLY FLOW PROGRESSING WNW INTO THE ALLEGHENIES. MOIST AND
COOLER EASTERLY LLVL FLOW IS LIMITING CAPE...BUT SHOWERS ARE
TAPPING THE 1.5" PW AIR AND HAVE SOME TROPICAL CHARACTERISTICS
WITH QUICK DOWNPOURS PRODUCING ONE TO TWO TENTHS OF AN INCH IN 15
TO 20 MINUTES. SHOWERS ARE MOVING ALONG NICELY SO NO FLOOD THREAT...
BUT WILL CONTINUE TO KEEP AN EYE ON THINGS...AS IT HAS BEEN WET
THE LAST 2 WEEKS.

BEST CONVERGENCE ALONG THE NOSE OF THE LLVL SELY FLOW PUSHES INTO
WESTERN AND NORTHERN PA THIS AFTERNOON. SOME CHC OF THUNDER IN
THESE AREAS...AS TEMPS HAVE WARMED UP NICELY TO THE NORTH AND WEST.
CAPES MAY NEAR 1000 IN THESE AREAS.

THE LARGEST AREA OF SHOWERS IS NOW LIFTING NW FROM JUST WEST
OF MDT.

CLOUD COVER...PRECIP AND EASTERLY FLOW OFF THE ATLANTIC WILL
RESULT IN MUCH COOLER TEMPS DURING THE DAY AND MILDER TEMPS
AT NIGHT...THEN OVER THE PAST WEEKEND.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/...
SCT SHRA WILL CONTINUE TO FALL OVER CENTRAL PA TONIGHT...AS MOIST
EASTERLY LL JET AND UPPER LVL DIVERGENCE REMAIN OVR THE AREA IN
ADVANCE OF UPPER LOW. A GENERAL DECREASE IN SHOWER ACTIVITY IS
EXPECTED LATE AS UPPER LOW OPENS UP AND LIFTS NE. BIGGER STORY
LATE TONIGHT COULD BE AREAS OF POTENTIALLY DENSE FOG. PLENTY OF
LL MOISTURE AND A NEARLY CALM WIND WILL BE FAVORABLE FOR FOG.

AS E COAST UPPER LOW OPENS UP AND LIFTS INTO THE CANADIAN
MARITIMES...UPSTREAM SHORTWAVE WILL DEEPEN AND CUTOFF OVR THE
TN VALLEY ON TUESDAY. LG SCALE FORCING AHEAD OF THIS FEATURE WILL
PRODUCE MORE SHRA/TSRA...MAINLY DURING THE AFT...AS SOME HEATING
TAKES PLACE...AND TEMPS WARM INTO THE 70S. GEFS/SREF DATA BOTH
SUGGEST BEST CHC OF SHRA/TSRA WILL BE ALONG THE SPINE OF THE
APPALACHIANS. OVERCAST SKIES AND VERY LGT WINDS ALOFT SUGGEST
THERE WILL BE VERY LITTLE THREAT OF SVR WX. BLEND OF GEFS/SREF
QPF RANGES FROM 0.2 TO 0.3 INCHES TONIGHT AND TUESDAY.

&&

.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
STILL SOME CHC OF A SHOWER OR THUNDERSTORM WED INTO FRIDAY...
MAINLY ACROSS THE SE DURING THE AFTERNOON AND PERHAPS EARLY
EVENING HOURS...AS THE REMAINS OF THE UPPER LVL LOW REMAIN
NEARBY.

GFS AND OTHERS MORE IN LINE WITH KEEPING FRONT NORTH OF OUR
AREA THIS COMING HOLIDAY WEEKEND...GFS WAS TOO COLD AND TOO
FAR SOUTH YESTERDAY WITH THINGS. EC HAS BEEN HINTING AT A
LARGE RIDGE BUILDING EASTWARD WITH TIME...AND VERY WARM
TEMPS. LEFT FCST DRY AFTER SAT...AS IF FRONT MAKES INTO
N PA...IT WOULD HAVE VERY LITTLE SUPPORT AND NOT MUCH MORE
THAN A WIND SHIFT LINE.

&&

.AVIATION /20Z MONDAY THROUGH SATURDAY/...
AN UPPER LOW OVER THE SOUTHEAST COAST WILL OPEN UP AND LIFT
NORTHEAST TONIGHT...AND AN INCREASING LL JET WILL BRING MOIST
SOUTHEAST FLOW AND GENERALLY POOR FLYING CONDITIONS TO THE REGION
OVER THE NEXT SEVERAL DAYS.

CIGS DETERIORATE FURTHER OVERNIGHT...BECOMING IFR AS AN UPPER
LEVEL TROF APPROACHES FROM THE GREAT LAKES.

OUTLOOK...
TUE-WED...WIDESPREAD MVFR/IFR CIGS AND VSBYS LIKELY IN SHOWERS
AND SCT TSRA.
THU...PRIMARILY VFR. SCT SHRA/TSTM POSS MAINLY SE.
FRI...PRIMARILY VFR. ISOLD SHRA/TSTM POSS MAINLY SE.
SAT...VFR. A CHC OF A SHOWER OR THUNDERSTORM ACROSS THE NORTH.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...DEVOIR/MARTIN
NEAR TERM...DEVOIR/MARTIN
SHORT TERM...DEVOIR/FITZGERALD/MARTIN
LONG TERM...MARTIN
AVIATION...DEVOIR/MARTIN/RXR

000
FXUS61 KPHI 211922
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
322 PM EDT MON MAY 21 2012

.SYNOPSIS...
A LOW PRESSURE SYSTEM OFF THE MIDDLE ATLANTIC COAST IS FORECAST TO
DRIFT SLOWLY NORTHEAST AND REACH THE CANADIAN MARITIMES ON
WEDNESDAY. THEREAFTER AN ATLANTIC HIGH PRESSURE SYSTEM WILL BUILD
WEST AND PERSIST INTO THE START OF THE MEMORIAL DAY WEEKEND. A
BACKDOOR COLD FRONT FROM EASTERN CANADA IS THEN FORECAST TO APPROACH
AND STALL NEAR THE REGION ON SUNDAY AND MONDAY.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
ONSHORE FLOW WILL CONTINUE AS LOW PRESSURE MOVES BY TO OUR EAST WITH
HIGH PRESSURE TO THE EAST OF THE CANADIAN MARITIMES.

LATEST RADAR IMAGERY CONTINUED TO SHOW WAVES OF SHOWERS IN THE ATLANTIC,
AND HAS DONE SO ALL DAY.  HOWEVER, THESE SHOWERS HAVE BEEN MOVG
SLOWLY WWD BUT HAVE HAD A HARD TIME MAKING IT INLAND EN MASSE OVER
SOUTH JERSEY.  NEVERTHELESS, SMALLER AREAS OF RAIN HAVE MADE IT
ONSHORE.  EXPECT MORE OF THE SAME OVERNIGHT WITH A CLOUDY SKY AND A
ELY FLOW 10 KTS OR LESS.  GUID TEMPS LOOK REASONABLE AND WAS GENLY
FOLLOWED.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/...
NOT MUCH CHANGE IN THE OVERALL TRENDS TOMORROW, EVEN THOUGH THE MDL
SOLNS AGAIN DIFFER ON HOW WET WE WILL BE.  THIS IS MAINLY DUE TO THE
FACT THAT ANY PRECIP WILL BE DEPENDENT ON THESE WAVES ON ELY FLOW
THAT HAVE BEEN DIFFICULT TO FORECAST MORE THAN A FEW HOURS IN
ADVANCE.  SO WHILE ALL MDLS FCST IT TO BE WARMER, THE MOST
OPTIMISTIC MDLS HAVE IT LESS DREARY AND THE MOST PESSIMISTIC...WELL
NOT SO MUCH...

ONCE AGAIN ANY PRECIP WAVES COULD PRODUCE LOCALLY HEAVY RAINFALL AS
THEY WILL BE SLOW MOVING, BUT OVERALL QPF WILL BE LIGHT.

&&

.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
ITS GOING TO BE A SLOW RECOVERY FROM PRECIPITATION CHANCES AS THE
LONG TERM PROGRESSES WITH SOME UNSEASONABLY WARM WEATHER EXPECTED
OVER THE MEMORIAL DAY WEEKEND. THE LAZY FLOW ALOFT IS MORE TYPICAL
OF LATE AUGUST THAN LATE MAY AND AS SUCH THE SLOW MOVING CONVECTION
WILL PRODUCE SOME LOCALLY HEAVY DOWNPOURS. CONVECTION SHOULD BE
DIURNALLY DRIVEN AND THERE WILL BE A TRAIL OFF IN THE POPS AT
NIGHT.

SO BEGINNING WITH TUESDAY NIGHT CONVECTIVE COVERAGE AND CHANCES WILL
LOWER AS THE NIGHT PROGRESSES. WE DROP THE MENTION OF THUNDER AFTER
THE EVENING. FORECAST SOUNDINGS SUGGEST EITHER LOW CLOUDS AND OR FOG
WILL FORM. FOR NOW WE KEPT THE MENTION OF PATCHY FOG AS CONFIDENCE
ABOUT ONE OVER THE OTHER IS NOT HIGH ENOUGH TO MAKE A CHOICE OR CHANGE.
STAT GUIDANCE WAS CLOSE AND ACCEPTED.

THE CLOSED LOW ACROSS THE SERN CONUS IS FORECAST TO COME CLOSER ON
WEDNESDAY DAY. WITH CONVECTIVE TEMPS FORECAST TO BE IN THE MID 70S
WITH SOME DPVA AND OMEGA FORECAST ESPECIALLY SOUTHWEST. WE UPPED
THE POPS TO LIKELY BY LATE AFTERNOON PRETTY MUCH FROM THE LEHIGH
AND DELAWARE VALLEY SOUTHWESTWARD. MODELS ARE ALSO HINTING AND
SOME CONVERGENCE FROM DIFFERENT BAY BREEZES ON THE DELMARVA
PENINSULA. DIFFERENCES AS TO FORECAST INSTAB, BUT THE OVERALL WIND
FIELD IS FORECAST TO BE VERY WEAK AND NOT MUCH OF A DROP OFF OF
THETA E WITH HEIGHT IN THE MID LEVELS. SO MAIN CONCERN LOOKS LIKE
LOCALLY HEAVY RAIN. GIVEN THE FORECAST CONVECTIVE TEMPS, STAT
GUIDANCE LOOKS REASONABLE.

WE THROTTLE DOWN THE PRECIPITATION CHANCES AGAIN ON WEDNESDAY NIGHT.
ON THURSDAY A HIGH PRESSURE SYSTEM FROM JAMES BAY IS FORECAST TO
BUILD OVER THE NEW ENGLAND COASTAL WATERS. ITS TRACK IS A BIT
FARTHER TO THE EAST THAN SOME OF THE DIRTY HIGHS WE HAVE HAD THIS
SPRING. NEVERTHELESS IT GIVES US PAUSE AS TO HOW WARM A DAY THURSDAY
WILL BE AND HOW MANY LOW CLOUDS WILL COME IN OFF THE OCEAN. AS FAR
AS POPS GO, THINKING GFS EASTWARD EMPHASIS MAY BE GIVING THE HIGH
TOO LITTLE CREDIT, SO WE LEANED HIGHEST POPS FARTHER TO THE WEST.

THE 500MB TROF IS STILL LINGERING INTO THURSDAY NIGHT AND FRIDAY, SO
WE MAINTAIN SOME CHANCES. THE MARINE INFLUENCE ON FRIDAY BY THE
SURFACE HIGH APPEARS LESS, SO WE WENT ALONG WITH A COMPROMISE
BETWEEN GFS AND EURO MOS FOR MAX TEMPS.

THEN FOR MEMORIAL DAY WEEKEND PRETTY MUCH THE GIRL WITH THE CURL
TYPE WEEKEND IT SEEMS FOR US, EITHER VERY GOOD OR VERY BAD, SELDOM
IN THE MIDDLE. THIS TIME THE MODELS ARE CONTINUING TO OUTLOOK WHAT
WOULD BE A "SUMMER" TIME WEEKEND. THERE IS PRETTY MUCH GOOD
AGREEMENT ABOUT A WARM DAY FOR SATURDAY WITH RELATIVELY SPEAKING
OUR LOWEST CHANCES FOR PRECIPITATION. AFTER THAT THERE REMAINS
DIFFERENCES AS TO HOW MUCH CAN A BACKDOOR FRONT SLIP TOWARD OR
INTO OUR CWA ON SUNDAY OR MONDAY. THE GFS HAS BEEN MORE
AGGRESSIVE. THE 12Z EURO HAS TRENDED THE GFS`S WAY BUT MORE IN A
YOU WON THE BATTLE BUT NOT NECESSARILY THE TEMPERATURE WAR. WE
HAVE SOME SLIGHT CHANCES IN BECAUSE OF THE PROXIMITY TO THE FRONT.
FOR NOW WE ARE BANKING ON NOT MUCH OF A THERMAL EFFECT FROM THE
FRONT WITH MAX TEMPS PROGGED MUCH CLOSER TO EC MOS THAN GFS MOS.

&&

.AVIATION /19Z MONDAY THROUGH SATURDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.

CONDS ACRS THE REGION RANGED FROM MVFR TO IFR WITH CLOUD COVER AND
SOME SHOWERS.  A LARGER AREA OF PRECIP LOOKS LIKE IT IS "FINALLY"
TRYING TO MOVE ONSHORE OVER S JERSEY.  THINGS IMPROVED FASTER THAN
EXPECTED THIS AFTN AND EXPECT THESE IMPROVEMENTS TO STAY OUTSIDE OF
ANY LOCAL SHOWERS THRU EARLY EVENING, WHEN A RETURN TO A MORE
GENERAL IFR AND EVENTUAL LIFR IN SOME AREAS IS ANTICIPATED
OVERNIGHT.

OVERALL, STILL NOT THE BEST PD TO BE FLYING.

OUTLOOK...
TUESDAY NIGHT THROUGH FRIDAY...MVFR OR IFR CONDS LATER EACH NIGHT
AND EARLY EACH DAY IN STRATUS OR FOG BECOMING VFR MIDDAY INTO THE
EVENING. LOCAL MVFR OR IFR CONDS IN SHOWERS OR TSTMS. OUTLOOKING
LESS COVERAGE AND DURATION OF IFR AND MVFR CONDITIONS ON FRIDAY.

SATURDAY...POSSIBLY SOME MVFR EARLY, OTHERWISE VFR.

&&

.MARINE...
THE PROLONGED ELY TO EVENTUALLY SELY FLOW WILL CONTINUE AND THE SCA
REMAINS IN PLACE.  WE OPTED TO CONVERT IT TO A SCA FOR HIGH SEAS AS
WE DON`T BELIEVE WINDS WILL PROLONGED BE A SIGNIFICANT FACTOR
OUTSIDE OF ANY SHOWERS OR TSTMS.  SO FAR THIS AFTN, SEAS HAVE
REMAINED BELOW CRITERIA, BUT WITH A LARGE AREA OF PRECIP OFF THE
COAST AND RADAR SHOWING ENHANCEMENT, EXPECT THINGS TO PICK UP.

OUTLOOK...
WE ARE EXPECTING SMALL CRAFT ADVISORY CONDITIONS FROM SEAS TO
PERSIST INTO TUESDAY NIGHT. AFTER THAT WE ARE NOT OUTLOOKING SMALL
CRAFT ADVISORY CONDITIONS TO BE MET THROUGH THE REST OF THE
DETERMINISTIC FORECAST. THE ONSHORE GRADIENT AND SWELLS FROM THE
HIGH BUILDING ACROSS THE CANADIAN MARITIMES IS NOT EXPECTED TO BE
STRONG ENOUGH TO GENERATE SMALL CRAFT CONDITIONS CENTERED AROUND
THURSDAY. AFTER THAT THE HIGH BUILDS FARTHER INTO OUR MARINE AREA
REDUCING THE THREAT OF SMALL CRAFT CONDITIONS EVEN FURTHER. THE
APPROACHING BACK DOOR FRONT SHOULD NOT BE AN ISSUE, IF EVER AT ALL,
THROUGH SATURDAY.

&&

.HYDROLOGY...
OCCASIONAL INSTABILITY IN ASSOCIATION WITH PERSISTENTLY HIGH HUMIDITY
AND COOL TROUGHING ALOFT WILL YIELD SOME LOCALLY HEAVY DOWNPOURS.
MOST OF THE AREA SHOULD RECEIVE HALF AN INCH THIS WEEK...INCLUDING
AMOUNTS THAT BEGAN THIS PAST SUNDAY EVENING. IF THERE WERE TO BE ANY
SMALL STREAM FLOOD PROBLEMS...IT WOULD MORE LIKELY OCCUR IN EASTERN
PENNSYLVANIA OR NORTHERN NEW JERSEY WHERE GRIDDED FLASH FLOOD
GUIDANCE SHOWS GREATER VULNERABILITY. 1 HR FFG NEAR 1.3 INCHES AND 6
TO 24 HR GUIDANCE IS CURRENTLY NEAR 1.9 INCHES. THAT WOULD PLACE
MONTGOMERY...WITH THE NEARBY CHESTER COUNTY PA BORDER AND CENTRAL
MORRIS COUNTY NJ AS SEEMINGLY MOST VULNERABLE.

&&

.RIP CURRENTS...
SWELL HEIGHTS NEAR 5 FEET...COMBINED WITH A DOMINANT 9 SECOND
PERIOD...WILL OUTWEIGH THE SLACKENING PRESSURE GRADIENT TUESDAY.
THE COMBINATION OF THE SWELL HEIGHT AND RELATIVELY LONG PERIOD
WILL RESULT IN A MODERATE RISK OF RIP CURRENTS TUESDAY. WHILE THE
COMBINATION SHOULD HAVE A LESSER EFFECT ON THE DELAWARE
BEACHES...IT WAS INCLUDED IN THE MODERATE RISK.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 AM EDT
     WEDNESDAY FOR ANZ450>455.

&&

$$
SYNOPSIS...GIGI
NEAR TERM...NIERENBERG
SHORT TERM...NIERENBERG
LONG TERM...GIGI
AVIATION...DRAG/GIGI/NIERENBERG
MARINE...GIGI/NIERENBERG
HYDROLOGY...DRAG
RIP CURRENTS...HAYES

000
FXUS61 KPBZ 211842
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
242 PM EDT MON MAY 21 2012

.SYNOPSIS...
RAIN CHANCES WILL BE ON THE INCREASE THROUGH TUESDAY AS A COLD
FRONT SLOWLY APPROACHES FROM THE WEST AND AS LOW PRESSURE MOVES UP
THE EAST COAST.

&&

.NEAR TERM /THROUGH TONIGHT/...

SHOWER AND THUNDERSTORM COVERAGE IS FORECAST TO INCREASE LATE THIS
AFTERNOON AND THIS EVENING AS BROAD MID LEVEL TROUGH EXTENDING
FROM THE UPPER MISSISSIPPI VALLEY TO THE SOUTHEAST COAST BECOMES
MORE INFLUENTIAL ON UPPER OHIO VALLEY WEATHER. MOISTURE SUPPLY IS
ON THE INCREASE WITH INFLUX VIA EASTERLY FLOW...AND CONVECTIVE
TEMPERATURES HAVE DROPPED WITH EROSION OF THE RIDGE. HOWEVER...GIVEN
THE WEAK WIND FIELD OVER THE REGION...SHOWER AND THUNDERSTORM COVERAGE
IS EXPECTED TO REMAIN SCATTERED AND SEVERE POTENTIAL LIMITED TO
PULSE-TYPE WIND GUSTS AS UPDRAFTS COLLAPSE WITHOUT ORGANIZATION.
WITH PRECIPITAL WATER VALUES RAP-ANALYZED ABOVE AN INCH...SOME
LOCALLY HEAVY RAINFALL CANNOT BE RULED OUT ALTHOUGH LACK OF
SUSTAINABILITY AS MENTIONED ABOVE SHOULD PRECLUDE PROBLEMS.

SHOWER CHANCES WILL BE MAINTAINED TONIGHT DESPITE THE WANING DIURNAL
SUPPORT AS MIDWESTERN SURFACE FRONT SLIDES EASTWARD WITH THE
PASSING OF SURFACE LOW PRESSURE.

OVERNIGHT LOWS WILL REMAIN RELATIVELY WARM AS INCREASED BOUNDARY
LAYER MOISTURE WILL PRECLUDE A DRAMATIC DROP. TEMPERATURES WERE
FORECAST USING A BLEND OF THE LATEST GUIDANCE.

&&

.SHORT TERM /TUESDAY THROUGH THURSDAY/...
PROGRESS OF THE FRONT WILL BE SLOW GIVEN THE AFOREMENTIONED WEAKNESS
OF THE OVERALL WIND FIELD. WITH PERSISTENT UPPER/MID LEVEL TROUGH FORECAST
OVER THE EASTERN CONUS...EXPECT CONVECTIVE TEMPERATURES TO REMAIN SUFFICIENTLY
LOW FOR DIURNALLY SUPPORTED SHOWER AND THUNDERSTORM DEVELOPMENT WITH
FOCUS VIA THE FRONT...RIDGES...OR OUTFLOW BOUNDARIES. WILL THUS FORECAST
LIKELY POPS ON TUESDAY WITH PASSAGE OF THE FRONT...FOLLOWED BY SCATTERED
PRECIP POTENTIAL THROUGH THE REMAINDER OF THE SHORT TERM.

WARM...HUMID CONDITIONS CAN BE EXPECTED TO CONTINUE THROUGH THE PERIOD.

&&

.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
UPPER TROUGH MOVING OFF TO THE EAST WILL STILL SPAWN ISOLATED
SHOWERS/THUNDERSTORMS FRIDAY. AFTER THAT...UPPER RIDGE WILL BUILD
INTO THE REGION AND REMAIN NEARLY STATIONARY. ISOLATED
SHOWERS/THUNDERSTORMS CANNOT BE RULED OUT AS A WEAK SURFACE FRONT
TRIES TO MOVE THROUGH. TEMPERATURES SHOULD BE WELL ABOVE
NORMAL...WITH UPPER 80S AND LOWER 90S EXPECTED FOR THE HOLIDAY
WEEKEND.

&&

.AVIATION /18Z MONDAY THROUGH SATURDAY/...
CLOUDS WILL CONTINUE TO INCREASE FROM EAST TO WEST AS LOW PRESSURE
MOVES IN FROM THE ATLANTIC OCEAN. IN ADDITION...A FRONT WILL
CROSS THE REGION VERY SLOWLY TONIGHT INTO TUESDAY. ISOLATED
SHOWERS WILL SLOWLY INCREASE IN COVERAGE...BUT WITH NO FOCUSING
MECHANISM TO PINPOINT A LOCATION...WILL NOT INCLUDE SHOWERS IN THE
TAFS AT THIS TIME. AN ISOLATED THUNDERSTORM CANNOT BE RULED OUT
EITHER. EASTERLY FLOW WILL ALLOW FOR ADDITIONAL LOW-LEVEL MOISTURE
TO MOVE IN AFTER MIDNIGHT...AND HAVE DROPPED ALL TAFS (EXCEPT ZZV)
TO IFR CONDITIONS IN FOG/STRATUS. CATEGORIES SHOULD RISE BACK TO
MVFR BY LATE TUESDAY MORNING.

.OUTLOOK...TUESDAY THROUGH SATURDAY...
SCATTERED SHOWERS ARE POSSIBLE THROUGH THURSDAY...WITH DIURNAL
CYCLE BRINGING GREATER COVERAGE DURING THE DAYTIME HOURS THAN
NIGHTTIME HOURS. AS THE FRONT MOVES THROUGH TUESDAY
AFTERNOON...SHOWERS APPEAR LIKELY FROM PITTSBURGH EAST FOR THIS
TIME PERIOD. SURFACE DEW POINTS WILL INCREASE THROUGH THE PERIOD
AND WILL LIKELY RESULT IN MVFR VISIBILITY RESTRICTIONS AT MOST
AIRPORT LOCATIONS DURING THE EARLY MORNING HOURS THROUGH THURSDAY.
COVERAGE OF SHOWERS SHOULD BE ISOLATED FOR FRIDAY AND SATURDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$

15/33

000
FXUS61 KPBZ 211730
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
130 PM EDT MON MAY 21 2012

.SYNOPSIS...
RAIN CHANCES WILL INCREASE EARLY THIS WEEK AS A COLD FRONT
SLOWLY APPROACHES FROM THE WEST AND AS LOW PRESSURE MOVES UP THE
EAST COAST.

&&

.NEAR TERM /THROUGH TONIGHT/...
SHOWER AND THUNDERSTORM COVERAGE IS STILL EXPECTED TO INCREASE
THIS AFTERNOON AS BROAD MID LEVEL TROUGH EXTENDING FROM THE UPPER
MISSISSIPPI VALLEY TO THE SOUTHEAST COAST BECOMES MORE INFLUENTIAL
ON UPPER OHIO VALLEY WEATHER. MOISTURE SUPPLY IS ON THE INCREASE
WITH INFLUX VIA EASTERLY FLOW...AND CONVECTIVE TEMPERATURES ARE
PROJECTED TO DROP WITH EROSION OF THE RIDGE. HOWEVER...GIVEN THE
WEAK WIND FIELD OVER THE REGION...SHOWER AND THUNDERSTORM COVERAGE
IS EXPECTED TO REMAIN SCATTERED AND SEVERE POTENTIAL LIMITED TO
PULSE-TYPE WIND GUSTS AS UPDRAFTS COLLAPSE WITHOUT ORGANIZATION.

SHOWER CHANCES WILL BE MAINTAINED TONIGHT DESPITE THE WANING DIURNAL
SUPPORT AS MIDWESTERN SURFACE FRONT SLIDES EASTWARD WITH THE
PASSING OF SURFACE LOW PRESSURE.

GIVEN VARIANCES IN CLOUD COVER AND TIMING OF RAIN DEVELOPMENT...HIGHS
TODAY WILL RANGE FROM SEASONAL READINGS OVER EASTERN ZONES TO AS
MUCH AS 10 DEGREES ABOVE AVERAGE OVER WESTERN COUNTIES OF THE
COUNTY WARNING AREA. OVERNIGHT LOWS WILL ALSO BE WARM AS INCREASED
BOUNDARY LAYER MOISTURE WILL PRECLUDE A DRAMATIC DROP.
TEMPERATURES WERE FORECAST USING THE LATEST NAM NUMBERS.

&&

.SHORT TERM /TUESDAY THROUGH THURSDAY/...
PROGRESS OF THE FRONT WILL BE SLOW GIVEN THE AFOREMENTIONED WEAKNESS
OF THE OVERALL WIND FIELD. WITH UPPER/MID LEVEL LOW FORECAST OVER
THE EASTERN CONUS...EXPECT CONVECTIVE TEMPERATURES TO REMAIN
SUFFICIENTLY LOW FOR DIURNALLY SUPPORTED SHOWER AND THUNDERSTORM
DEVELOPMENT WITH FOCUS VIA THE FRONT...RIDGES...OR OUTFLOW
BOUNDARIES. WILL THUS FORECAST LIKELY POPS ON TUESDAY WITH PASSAGE
OF THE FRONT...FOLLOWED BY SCATTERED PRECIP POTENTIAL THROUGH
THE REMAINDER OF THE SHORT TERM.

WARM...HUMID CONDITIONS CAN BE EXPECTED TO CONTINUE THROUGH THE
PERIOD.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
UPPER TROUGH MOVING OFF TO THE EAST WILL STILL SPAWN ISOLATED
SHOWERS/THUNDERSTORMS FRIDAY. AFTER THAT...UPPER RIDGE WILL BUILD
INTO THE REGION AND REMAIN NEARLY STATIONARY. ISOLATED
SHOWERS/THUNDERSTORMS CANNOT BE RULED OUT AS A WEAK SURFACE FRONT
TRIES TO MOVE THROUGH. TEMPERATURES SHOULD BE WELL ABOVE
NORMAL...WITH UPPER 80S AND LOWER 90S EXPECTED FOR THE HOLIDAY
WEEKEND.

&&

.AVIATION /17Z MONDAY THROUGH SATURDAY/...
CLOUDS WILL CONTINUE TO INCREASE FROM EAST TO WEST AS LOW PRESSURE
MOVES IN FROM THE ATLANTIC OCEAN. IN ADDITION...A FRONT WILL
CROSS THE REGION VERY SLOWLY TONIGHT INTO TUESDAY. ISOLATED
SHOWERS WILL SLOWLY INCREASE IN COVERAGE...BUT WITH NO FOCUSING
MECHANISM TO PINPOINT A LOCATION...WILL NOT INCLUDE SHOWERS IN THE
TAFS AT THIS TIME. AN ISOLATED THUNDERSTORM CANNOT BE RULED OUT
EITHER. EASTERLY FLOW WILL ALLOW FOR ADDITIONAL LOW-LEVEL MOISTURE
TO MOVE IN AFTER MIDNIGHT...AND HAVE DROPPED ALL TAFS (EXCEPT ZZV)
TO IFR CONDITIONS IN FOG/STRATUS. CATEGORIES SHOULD RISE BACK TO
MVFR BY LATE TUESDAY MORNING.

.OUTLOOK...TUESDAY THROUGH SATURDAY...
SCATTERED SHOWERS ARE POSSIBLE THROUGH THURSDAY...WITH DIURNAL
CYCLE BRINGING GREATER COVERAGE DURING THE DAYTIME HOURS THAN
NIGHTTIME HOURS. AS THE FRONT MOVES THROUGH TUESDAY
AFTERNOON...SHOWERS APPEAR LIKELY FROM PITTSBURGH EAST FOR THIS
TIME PERIOD. SURFACE DEW POINTS WILL INCREASE THROUGH THE PERIOD
AND WILL LIKELY RESULT IN MVFR VISIBILITY RESTRICTIONS AT MOST
AIRPORT LOCATIONS DURING THE EARLY MORNING HOURS THROUGH THURSDAY.
COVERAGE OF SHOWERS SHOULD BE ISOLATED FOR FRIDAY AND SATURDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$

000
FXUS61 KPHI 211643
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1243 PM EDT MON MAY 21 2012

.SYNOPSIS...
LOW PRESSURE ALONG THE EAST COAST WILL PERSIST THROUGH WEDNESDAY.
THEREAFTER...CENTRAL ATLANTIC HIGH PRESSURE WILL CONTINUE A
SOUTHERLY FLOW OF RELATIVELY HUMID AIR UP THE EAST COAST THURSDAY
INTO AT LEAST THE START OF THE MEMORIAL DAY WEEKEND. THE PASSAGE OF
ANY COOL FRONT HERE ON SUNDAY OR MONDAY IS HIGHLY UNCERTAIN AND IF
IT DOESN`T OCCUR...HOT WEATHER WILL ARRIVE FROM OHIO VALLEY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE LARGE HIGH PRESSURE SYSTEM OFF THE CANADIAN WATERS AND LOW
PRESSURE OFF THE SOUTHEAST U.S. COAST WILL CONTINUE THE ONSHORE FLOW
OVER THE AREA TODAY. WEAK DISTURBANCES EMBEDDED IN THE FLOW WILL
PROVIDE OPPORTUNITIES FOR SHOWERS ACROSS THE AREA TODAY. THE
TIMING OF THESE DISTURBANCES IS DIFFICULT...BUT THE WEATHER IS
NOT EXPECTED TO MAKE ANY GREAT IMPROVEMENTS TODAY.

THE AREA OF SHOWERS ACROSS NORTHERN NEW JERSEY HAS PUSHED A LITTLE
BIT FURTHER NORTHWARD AND HAS ALLOWED FOR SOME AREAS TO GT A
LITTLE BIT OF A BREAK FROM THE RAIN. THE LARGER AREA OFFSHORE HAS
BEEN SLOWLY MAKING PROGRESS WESTWARD. HOWEVER, IT IS HAVING A HARD
TIME MOVING INLAND, ESPECIALLY ALONG THE DELAWARE AND SOUTHERN NEW
JERSEY COASTS. THE NORTHERN EXTENT OF THIS AREA IS PUSHING LAND
INTO OCEAN AND MONMOUTH COUNTIES. SOME SHOWERS ARE POPPING UP IN
AHEAD OF THE LARGER BATCH OF RAIN SO AREAS WHERE IT HAS BEEN DRIER
MAY START TO SEE SOME MORE RAIN AS THE DAY PROGRESSES.

LOWERED MAX TEMPERATURES ACROSS NORTHERN AREAS BY A FEW DEGREES AS
LIMITED HEATING IS OCCURRING AND THE RAIN IS KEEPING THE COLUMN
COOLER AS WELL.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM TUESDAY/...
NOT MUCH CHANGE TONIGHT. ONE SFC LOW WILL MOVE UP ALONG THE WATERS
TONIGHT...OTHER SHORTWAVES ALOFT WILL TRAVERSE THE AREA. POPS ARE
REDUCED BACK TO LOW LIKELY OR HIGH CHC POPS FOR TONIGHT. QPF AROUND
.10 TO .25 ACROSS THE AREA. WINDS BACK AROUND FROM ERLY TO NRLY AS
THE LOW MOVES NORTHWARD WELL EAST OF THE WATERS.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
TEMPERATURES: AVERAGE A BIT ABOVE NORMAL MOST OF THIS WORKWEEK
"POSSIBLY" TRENDING SUBSTANTIALLY ABOVE NORMAL THIS ENTIRE MEMORIAL
DAY WEEKEND...WITH THE CAVEAT THAT A BACKDOOR COLD FRONT MOVING
DOWN THROUGH NEW ENGLAND DOES NOT COME IN THE SIDE DOOR DOWN
HERE...IN OTHER WORDS...SLIDING SOUTHWEST THROUGH NEW JERSEY AND
DELAWARE.

THE HUMID CONDITIONS AND CONSIDERABLE CLOUDINESS MOST OF THIS WEEK
WILL FORCE NIGHTTIMES TO BE NOTABLY ABOVE NORMAL /5 TO 10 DEGREES
ON A DAILY BASIS/ WITH OUR DAYTIME MAXIMUM TEMPS CLOSER TO NORMAL.

WE ARE AWARE THE ECMWF IS CONSIDERABLY COOLER ON OUR DAYTIME MAX
TEMPS MUCH OF THIS WORKWEEK AND THEN WELL ABOVE OUR FORECAST FOR
NEXT SUNDAY AND MONDAY.

CLOUD COVER AND TIMING OF THE SHOWERY WEATHER CREATES THE UNCERTAINTY
OF FORECASTING MAX TEMPS THIS WORKWEEK AND THEN THE UNCERTAIN PASSAGE
OF ANY COLD FRONT HERE NEXT WEEKEND LIMITS EXPRESSION OF CONFIDENCE
REGARDING A POTENTIAL HEAT WAVE STARTING HERE SOMETIME DURING THE
MEMORIAL DAY WEEKEND.

500 MB: TROUGHING ALOFT IN THE EASTERN UNITED STATES PRODUCES A
PERSISTENTLY MORE HUMID AND INTERMITTENTLY SHOWERY REGIME HERE
THIS WEEK. THE TROUGH WILL BE REPLACED BY STRONG RIDGING...AND
DRYING ALOFT...RESULTING IN HEAT WAVE CONDITIONS OF 90 DEGREE HEAT
IN THE MIDWEST AND SOUTHERN UNITED STATES EVENTUALLY BUILDING
NORTHEASTWARD TOWARD OR INTO OUR AREA DURING THE MEMORIAL DAY
WEEKEND.


THE DAILIES...

TUESDAY THROUGH FRIDAY...WEAK FORCING AND OCCASIONAL INSTABILITY
WILL PRODUCE BANDS OF SHOWERS. SINCE THE STEERING WINDS ALOFT WILL
BE VERY LIGHT...THE BANDS OF CONVECTION WILL BE SLOW MOVING...
PERMITTING BANDS OR POCKETS OF HEAVY RAINFALL.  DAILY DETAILS CANNOT
BE RELIABLY OFFERED SO A BLEND OF 00Z/21 NCEP MOS GUIDANCE WAS USED
TO DEVELOP THE FCST ELEMENTS. WE NOTE THE ECMWF IS COOLER THAN OUR
330 AM DETERMINISTIC FCST THIS WEEK...BUT I THINK THIS IS LARGELY
PREDICATED ON THEIR CONSTANCY OF SHOWERY WEATHER. USUALLY IN THESE
PATTERNS THERE ARE LARGE CHUNKS OF TIME WHEN ITS NOT RAINING.
CONFIDENCE IMAGERY FOCUSED ON GFS 2M TEMPS FROM FSU EXPRESSES
ABOVE AVERAGE CONFIDENCE IN THE GFS 2M TEMP FCST THIS WEEK...IN
OTHER WORDS LEANING WARMER WHEN COMPARING THE 00Z/21 GFS TO THE
00Z/21 ECMWF IS THE WAY TO THINK ATTM.

MEMORIAL DAY WEEKEND...ON THE OTHER HAND...A DRYING OUT DOWN TO
800 MB AND HEATING UP IS FORECAST THIS 3 DAY PERIOD AND HERE THE
GFS 2M TEMP FCST IS EXPRESSING LESS THAN AVERAGE CONFIDENCE FOR
THIS 00Z/21 CYCLE. THAT SUGGESTS TO ME THAT THE ECMWF AND UKMET
ARE ON THE RIGHT TRACK SENDING 90 DEGREE HEAT INTO THE MID
ATLANTIC STATES BY SUNDAY OR MONDAY. THERE IS MODEL SPREAD ON THE
SOLUTION WHICH MEANS WE CANT BE SURE HOW WARM IT BECOME. THERE
STILL MAY BE CONSIDERABLE MOISTURE BELOW 800MB WHICH COULD LIMIT
REALIZING THE POTENTIAL THAT 850 MB TEMPS WILL BE OFFERING.

IN ANY CASE...THE SHOWERY WEATHER OF THIS WORK WEEK SHOULD BE
ALMOST NON EXISTENT THIS WEEKEND DUE TO SUBSIDENCE ASSOCIATED
WITH THE VERY STRONG RIDGE DEVELOPING ALOFT.

&&

.AVIATION /16Z MONDAY THROUGH FRIDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.

A LARGE AREA OF PRECIP IS LURKING OFF THE NJ COAST AND MOVING
SLOWLY WWD. EARLIER THINKING WAS THAT THIS RAIN WOULD MOVE OVER
THE TAF SITES FROM KACY TO KTTN AND COULD HELP RAISE CIGS TO
PERHAPS MVFR. UNFORTUNATELY, THIS PRECIP IS NOT MOVG VERY MUCH AT
ALL AND WITHOUT IT, CIGS ARE PRETTY MUCH GOING TO STAY WHERE THEY
ARE. THERE HAVE BEEN SOME SHOWERS AHEAD OF THE MAIN SURGE BUT
THESE HAVE BEEN HAVING A HARD TIME MAKING IT WWD AS WELL. SO,
FUTURE TAF AMENDMENTS WILL LIKELY PUSH BACK AND POSSIBLY ELIMINATE
THE CIG IMPROVEMENTS FCST, SUBJECT TO RADAR TRENDS AT THAT TIME.

OVERALL, POOR FLYING CONDS ARE EXPECTED TO CONTINUE.  SCT TSRA CAN
NOT BE RULED OUT FOR AREA ARPTS, ESPECIALLY ACRS NJ, WHICH ONLY
FURTHER COMPLICATES MATTERS.  CHC OF OCCURRENCE AT ANY INDIVIDUAL
SITE IS LOW BUT ITS THERE, NONETHELESS.

OUTLOOK...
TUESDAY THROUGH FRIDAY...MVFR OR IFR CONDS LATER EACH NIGHT AND
EARLY EACH DAY IN ST/FOG BECOMES VFR CIGS MIDDAY INTO THE EVENING.
LOCAL MVFR OR IFR CONDS IN SCATTERED SHOWERS OR EVEN A TSTM. LIGHT
WIND...TENDING TO BE MOSTLY SOUTHEAST TO SOUTH.

&&

.MARINE...
WINDS HAVE DECREASED ACROSS THE LOWER DELAWARE BAY AND THE SMALL
CRAFT ADVISORY WAS ALLOWED TO EXPIRE. OTHERWISE, ONGOING SCA
CONDITIONS WILL CONTINUE ON THE OCEAN FOR SEVERAL PERIODS (BEYOND
THE SHORT TERM) WHILE EITHER LOW END SCA OR MARGINALLY CLOSE TO
SCA CONDITIONS FOR THE LOWER DEL BAY OVER THE NEXT FEW DAYS.
SHOWERY CONDITIONS TODAY WITH A FEW TSTMS...MOSTLY OVER THE SRN
COASTAL WATERS.


OUTLOOK...
TUESDAY THROUGH FRIDAY.

WIND SPEEDS ARE FORECAST TO REMAIN BELOW THE SMALL CRAFT ADVISORY
CRITERION.

WAVE HEIGHTS ON OUR OCEAN WATERS MAY BE FLIRTING WITH HAZARDOUS
SEAS CRITERIA AT TIMES...ESPECIALLY TUESDAY...BUT FOR NOW...OTHER
THAN A 3 TO 4 FT SE SWELL OF 8 SECONDS...MUCH OF THIS TIME SHOULD
BE SCA FREE.

&&

.HYDROLOGY...
OCCASIONAL INSTABILITY IN ASSOCIATION WITH PERSISTENTLY HIGH HUMIDITY
AND COOL TROUGHING ALOFT WILL PROBABLY YIELD A COUPLE OF SWATHS OF
STORM TOTALS EXCEEDING 3 INCHES THIS WEEK. MOST OF THE AREA SHOULD
BE DOUSED BY AT LEAST HALF AN INCH THIS WEEK...INCLUDING AMOUNTS
THAT BEGAN THIS PAST SUNDAY EVENING. IF THERE WERE TO BE ANY SMALL
STREAM FLOOD PROBLEMS...IT WOULD MORE LIKELY OCCUR IN EASTERN
PENNSYLVANIA OR NORTHEAST NEW JERSEY WHERE GRIDDED FLASH FLOOD
GUIDANCE SHOWS GREATER VULNERABILITY. 1 HR FFG NEAR 1.3 INCHES AND
6 TO 24 HR GUIDANCE IS CURRENTLY NEAR 1.9 INCHES. THAT WOULD PLACE
MONTGOMERY...WITH THE NEARBY CHESTER COUNTY PA BORDER AND CENTRAL
MORRIS COUNTY NJ AS SEEMINGLY MOST VULNERABLE.

&&

.RIP CURRENTS...
WHILE THE ONSHORE FLOW WILL PERSIST TODAY, IT IS FORECAST TO NOT
BE AS STRONG AS YESTERDAY. SEAS ARE LESS THAN YESTERDAY BY 2 FEET
BUT THE SE SWELL IS STILL NEAR 5 FEET WITH AN 8 SECOND PERIOD. BASED
ON THIS, WE PROBABLY WILL HAVE A MODERATE RISK OF RIP CURRENTS
TODAY.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT TUESDAY FOR ANZ452>455.
     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 AM EDT TUESDAY
     FOR ANZ450-451.

&&

$$
SYNOPSIS...DRAG
NEAR TERM...MEOLA/O`HARA
SHORT TERM...O`HARA
LONG TERM...DRAG
AVIATION...DRAG/NIERENBERG
MARINE...DRAG/MEOLA/O`HARA
HYDROLOGY...
RIP CURRENTS...

000
FXUS61 KCTP 211523
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1123 AM EDT MON MAY 21 2012

.SYNOPSIS...
AN UPPER LOW OVER THE SOUTHEAST COAST WILL OPEN UP AND LIFT
NORTHEAST TODAY AND TONIGHT. A DEEPENING SHORTWAVE WILL SLOW DOWN
AND CUT OFF OVR THE CENTRAL APPALACHIANS DURING THE MIDDLE OF THE
WEEK. PENNSYLVANIA WILL BE ON THE EDGE OF THE REBUILDING UPPER RIDGE
ACROSS THE OHIO VALLEY BY THE END OF NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPPER LOW OVER THE CAROLINA COAST WILL LIFT NORTH ALONG THE E
COAST DURING THE NEXT 24HRS. MOIST...EASTERLY LL JET AND UPPER
LVL DIVERGENCE PRECEDING THE UPPER LOW WILL BRING SHOWERS TO MOST
OF CENTRAL PA THIS AFTERNOON. CIRCULATION AROUND BROAD UPPER LOW
OVER THE SOUTHEASTERN UNITED STATES AND WESTERN ATLANTIC AND SFC
HIGH TO THE EAST OF NEW ENGLAND IS DIRECTING HIGHER PW AIR INTO
SOUTHEAST AND CENTRAL PA THIS MORNING...COINCIDING WITH MARITIME
EASTERLY FLOW PROGRESSING WNW INTO THE ALLEGHENIES THIS MORNING.
MOIST AND COOLER EASTERLY LLVL FLOW IS LIMITING CAPE...BUT SHOWERS
ARE TAPPING THE 1.5" PW AIR AND HAVE SOME TROPICAL CHARACTERISTICS
WITH QUICK DOWNPOURS PRODUCING ONE TO TWO TENTHS OF AN INCH IN 15
TO 20 MINUTES. SHOWERS ARE MOVING ALONG NICELY SO NO FLOOD THREAT.
BEST CONVERGENCE ALONG THE NOSE OF THE LLVL SELY FLOW PUSHES INTO
WESTERN AND NORTHERN PA THIS AFTERNOON...BUT UPSTREAM SHOWERS CONT
TO DEVELOP AND WILL BE SCATTERED ABOUT THE RIDGE AND VALLEY AND
CENTRAL MOUNTAIN REGIONS AFTER A LATE MORNING/EARLY AFTERNOON
BREAK IN THE ACTIVITY.

CLOUD COVER...PRECIP AND EASTERLY FLOW OFF THE ATLANTIC WILL
RESULT IN MUCH COOLER TEMPS TODAY WITH MAXIMUMS ONLY ARND 70F.
BLEND OF OPER AND ENSEMBLE QPF INDICATES LIKELY RAINFALL AMTS
TODAY OF BTWN 0.1 AND 0.2 INCHES.

DOWNSLOPING SE FLOW WILL RESULT IN PARTIAL SUNSHINE AND A
SOMEWHAT WARMER MONDAY OVR WARREN COUNTY...WHERE A LATE DAY
TSRA IS POSSIBLE. OPER GFS/NAM INDICATE CAPE VALUES NR 1000JK-1
ACROSS WARREN CO BY THIS EVENING. FURTHER EAST...A COOLER MORE
STABLE EASTERLY FLOW WILL LIKELY PRECLUDE THUNDER.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
SCT SHRA WILL CONTINUE TO FALL OVER CENTRAL PA TONIGHT...AS MOIST
EASTERLY LL JET AND UPPER LVL DIVERGENCE REMAIN OVR THE AREA IN
ADVANCE OF UPPER LOW. A GENERAL DECREASE IN SHOWER ACTIVITY IS
EXPECTED LATE TONIGHT AS UPPER LOW OPENS UP AND LIFTS NE. BIGGER
STORY LATE TONIGHT COULD BE AREAS OF POTENTIALLY DENSE FOG. PLENTY
OF LL MOISTURE AND A NEARLY CALM WIND WILL BE FAVORABLE FOR FOG.

AS E COAST UPPER LOW OPENS UP AND LIFTS INTO THE CANADIAN
MARITIMES...UPSTREAM SHORTWAVE WILL DEEPEN AND CUT OFF OVR THE
TENN VALLEY ON TUESDAY. LG SCALE FORCING AHEAD OF THIS FEATURE
WILL PRODUCE MORE SHRA/TSRA TUESDAY. GEFS/SREF DATA BOTH SUGGEST
BEST CHC OF SHRA/TSRA WILL BE ALONG THE SPINE OF THE APPALACHIANS.
OVERCAST SKIES AND VERY LGT WINDS ALOFT SUGGEST THERE WILL BE VERY
LITTLE THREAT OF SVR WX. BLEND OF GEFS/SREF QPF RANGES FROM 0.2 TO
0.3 INCHES TONIGHT AND TUESDAY.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
RELATIVELY GOOD AGREEMENT AMONG MED RANGE GUIDANCE LATER THIS
WEEK...ALL OF WHICH INDICATES UPPER LOW SLOWLY LIFTING NORTH ALONG
THE CENTRAL APPALACHIANS. THIS SCENARIO SUPPORTS THE CHC OF
DIURNALLY ENHANCED SHRA/TSRA WED-THU AND POSSIBLY EVEN FRIDAY. NEARLY
ALL MDL DATA TRACKS TS ALBERTO WELL EAST OFF THE MID ATLANTIC
COAST TUE NIGHT WITH NO DIRECT IMPACT ON PA.

TEMPS THIS WEEK LOOK TO BE ABOVE NORMAL...MAINLY DUE TO WARM
OVERNIGHT LOWS. DEEP SOUTHERLY FLOW AHEAD OF UPPER LOW WILL
TRANSPORT ABOVE NORMAL MOISTURE NORTH ALONG THE E COAST...RESULTING
IN THE WARM NIGHTS.

EVEN WARMER WX APPEARS VERY LIKELY BY NEXT WEEKEND WHEN ALL MDL
DATA INDICATES A BUILDING UPPER LVL RIDGE OVER THE OHIO VALLEY.
HOWEVER...PA MAY BE ON PERIPHERY OF THIS FEATURE...PLACING AT
LEAST NORTHERN PA IN RING OF FIRE WITH CHC OF PM CONVECTION.

&&

.AVIATION /16Z MONDAY THROUGH FRIDAY/...
15Z TAFS UPDATED SEVERAL TIMES FOR CURRENT AND EXPECTED
CONDITIONS OVER THE NEXT FEW HOURS.

FIRST BATCH OF SHOWERS LOOKS LIKE IT WILL MAKE IT TO BFD...
CLDS BUILDING UP TO THE WEST. LEFT THUNDER OUT OF BFD FOR NOW.

NEXT BATCH OF SHOWERS WEST OF MDT...SEVERAL HOURS AWAY FROM
OTHER TAF SITES.

EARLIER DISCUSSION BELOW.

AN UPPER LOW OVER THE SOUTHEAST COAST WILL OPEN UP
AND LIFT NORTHEAST TODAY AND TONIGHT...AND AN INCREASING LL JET
WILL BRING MOIST SOUTHEAST FLOW AND GENERALLY POOR FLYING
CONDITIONS TO THE REGION OVER THE NEXT SEVERAL DAYS.

INCREASING MOISTURE HAS ALREADY RESULTED IN LOWERING CIGS ACROSS
MUCH OF CENTRAL PA. IFR CIGS PREVALENT IN THE LOWER SUSQ...WITH
MVFR GRADUALLY SPREADING NW ACROSS CENTRAL MTNS. SHOWERS WILL ALSO
INCREASE FROM THE SE DURING THE DAY TODAY...WITH NORTHERN EDGE OF
SHOWERS REACHING FROM AROUND JST-UNV-IPT BY LATE MORNING.

CIGS DETERIORATE FURTHER OVERNIGHT...BECOMING IFR AS AN UPPER
LEVEL TROF APPROACHES FROM THE GREAT LAKES.

OUTLOOK...
MON NIGHT-WED...WIDESPREAD MVFR/IFR CIGS AND VSBYS LIKELY IN
SHOWERS AND SCT TSRA.
THU...PRIMARILY VFR. SCT SHRA/TSTM POSS MAINLY SE.
FRI...PRIMARILY VFR. ISOLD SHRA/TSTM POSS MAINLY SE.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...FITZGERALD
NEAR TERM...DEVOIR/FITZGERALD
SHORT TERM...FITZGERALD
LONG TERM...FITZGERALD/MARTIN
AVIATION...MARTIN/RXR

000
FXUS61 KCTP 211458
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1058 AM EDT MON MAY 21 2012

.SYNOPSIS...
AN UPPER LOW OVER THE SOUTHEAST COAST WILL OPEN UP AND LIFT
NORTHEAST TODAY AND TONIGHT. A DEEPENING SHORTWAVE WILL SLOW DOWN
AND CUT OFF OVR THE CENTRAL APPALACHIANS DURING THE MIDDLE OF THE
WEEK. PENNSYLVANIA WILL BE ON THE EDGE OF THE REBUILDING UPPER RIDGE
ACROSS THE OHIO VALLEY BY THE END OF NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPPER LOW OVER THE CAROLINA COAST WILL LIFT NORTH ALONG THE E
COAST DURING THE NEXT 24HRS. MOIST...EASTERLY LL JET AND UPPER
LVL DIVERGENCE PRECEDING THE UPPER LOW WILL BRING SHOWERS TO MOST
OF CENTRAL PA THIS AFTERNOON. CIRCULATION AROUND BROAD UPPER LOW
OVER THE SOUTHEASTERN UNITED STATES AND WESTERN ATLANTIC AND SFC
HIGH TO THE EAST OF NEW ENGLAND IS DIRECTING HIGHER PW AIR INTO
SOUTHEAST AND CENTRAL PA THIS MORNING...COINCIDING WITH MARITIME
EASTERLY FLOW PROGRESSING WNW INTO THE ALLEGHENIES THIS MORNING.
MOIST AND COOLER EASTERLY LLVL FLOW IS LIMITING CAPE...BUT SHOWERS
ARE TAPPING THE 1.5" PW AIR AND HAVE SOME TROPICAL CHARACTERISTICS
WITH QUICK DOWNPOURS PRODUCING ONE TO TWO TENTHS OF AN INCH IN 15
TO 20 MINUTES. SHOWERS ARE MOVING ALONG NICELY SO NO FLOOD THREAT.
BEST CONVERGENCE ALONG THE NOSE OF THE LLVL SELY FLOW PUSHES INTO
WESTERN AND NORTHERN PA THIS AFTERNOON...BUT UPSTREAM SHOWERS CONT
TO DEVELOP AND WILL BE SCATTERED ABOUT THE RIDGE AND VALLEY AND
CENTRAL MOUNTAIN REGIONS AFTER A LATE MORNING/EARLY AFTERNOON
BREAK IN THE ACTIVITY.

CLOUD COVER...PRECIP AND EASTERLY FLOW OFF THE ATLANTIC WILL
RESULT IN MUCH COOLER TEMPS TODAY WITH MAXIMUMS ONLY ARND 70F.
BLEND OF OPER AND ENSEMBLE QPF INDICATES LIKELY RAINFALL AMTS
TODAY OF BTWN 0.1 AND 0.2 INCHES.

DOWNSLOPING SE FLOW WILL RESULT IN PARTIAL SUNSHINE AND A
SOMEWHAT WARMER MONDAY OVR WARREN COUNTY...WHERE A LATE DAY
TSRA IS POSSIBLE. OPER GFS/NAM INDICATE CAPE VALUES NR 1000JK-1
ACROSS WARREN CO BY THIS EVENING. FURTHER EAST...A COOLER MORE
STABLE EASTERLY FLOW WILL LIKELY PRECLUDE THUNDER.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
SCT SHRA WILL CONTINUE TO FALL OVER CENTRAL PA TONIGHT...AS MOIST
EASTERLY LL JET AND UPPER LVL DIVERGENCE REMAIN OVR THE AREA IN
ADVANCE OF UPPER LOW. A GENERAL DECREASE IN SHOWER ACTIVITY IS
EXPECTED LATE TONIGHT AS UPPER LOW OPENS UP AND LIFTS NE. BIGGER
STORY LATE TONIGHT COULD BE AREAS OF POTENTIALLY DENSE FOG. PLENTY
OF LL MOISTURE AND A NEARLY CALM WIND WILL BE FAVORABLE FOR FOG.

AS E COAST UPPER LOW OPENS UP AND LIFTS INTO THE CANADIAN
MARITIMES...UPSTREAM SHORTWAVE WILL DEEPEN AND CUT OFF OVR THE
TENN VALLEY ON TUESDAY. LG SCALE FORCING AHEAD OF THIS FEATURE
WILL PRODUCE MORE SHRA/TSRA TUESDAY. GEFS/SREF DATA BOTH SUGGEST
BEST CHC OF SHRA/TSRA WILL BE ALONG THE SPINE OF THE APPALACHIANS.
OVERCAST SKIES AND VERY LGT WINDS ALOFT SUGGEST THERE WILL BE VERY
LITTLE THREAT OF SVR WX. BLEND OF GEFS/SREF QPF RANGES FROM 0.2 TO
0.3 INCHES TONIGHT AND TUESDAY.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
RELATIVELY GOOD AGREEMENT AMONG MED RANGE GUIDANCE LATER THIS
WEEK...ALL OF WHICH INDICATES UPPER LOW SLOWLY LIFTING NORTH ALONG
THE CENTRAL APPALACHIANS. THIS SCENARIO SUPPORTS THE CHC OF
DIURNALLY ENHANCED SHRA/TSRA WED-THU AND POSSIBLY EVEN FRIDAY. NEARLY
ALL MDL DATA TRACKS TS ALBERTO WELL EAST OFF THE MID ATLANTIC
COAST TUE NIGHT WITH NO DIRECT IMPACT ON PA.

TEMPS THIS WEEK LOOK TO BE ABOVE NORMAL...MAINLY DUE TO WARM
OVERNIGHT LOWS. DEEP SOUTHERLY FLOW AHEAD OF UPPER LOW WILL
TRANSPORT ABOVE NORMAL MOISTURE NORTH ALONG THE E COAST...RESULTING
IN THE WARM NIGHTS.

EVEN WARMER WX APPEARS VERY LIKELY BY NEXT WEEKEND WHEN ALL MDL
DATA INDICATES A BUILDING UPPER LVL RIDGE OVER THE OHIO VALLEY.
HOWEVER...PA MAY BE ON PERIPHERY OF THIS FEATURE...PLACING AT
LEAST NORTHERN PA IN RING OF FIRE WITH CHC OF PM CONVECTION.

&&

.AVIATION /15Z MONDAY THROUGH FRIDAY/...
AN UPPER LOW OVER THE SOUTHEAST COAST WILL OPEN UP AND LIFT
NORTHEAST TODAY AND TONIGHT...AND AN INCREASING LL JET WILL
BRING MOIST SOUTHEAST FLOW AND GENERALLY POOR FLYING CONDITIONS
TO THE REGION OVER THE NEXT SEVERAL DAYS.

INCREASING MOISTURE HAS ALREADY RESULTED IN LOWERING CIGS ACROSS
MUCH OF CENTRAL PA. IFR CIGS PREVALENT IN THE LOWER SUSQ...WITH
MVFR GRADUALLY SPREADING NW ACROSS CENTRAL MTNS. SHOWERS WILL ALSO
INCREASE FROM THE SE DURING THE DAY TODAY...WITH NORTHERN EDGE OF
SHOWERS REACHING FROM AROUND JST-UNV-IPT BY LATE MORNING.

CIGS DETERIORATE FURTHER OVERNIGHT...BECOMING IFR AS AN UPPER
LEVEL TROF APPROACHES FROM THE GREAT LAKES.

OUTLOOK...
MON NIGHT-WED...WIDESPREAD MVFR/IFR CIGS AND VSBYS LIKELY IN
SHOWERS AND SCT TSRA.
THU...PRIMARILY VFR. SCT SHRA/TSTM POSS MAINLY SE.
FRI...PRIMARILY VFR. ISOLD SHRA/TSTM POSS MAINLY SE.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...FITZGERALD
NEAR TERM...DEVOIR/FITZGERALD
SHORT TERM...FITZGERALD
LONG TERM...FITZGERALD/MARTIN
AVIATION...RXR

000
FXUS61 KPBZ 211417
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
1017 AM EDT MON MAY 21 2012

.SYNOPSIS...
RAIN CHANCES WILL INCREASE EARLY THIS WEEK AS A COLD FRONT
SLOWLY APPROACHES FROM THE WEST AND AS LOW PRESSURE MOVES UP THE
EAST COAST.

&&

.NEAR TERM /THROUGH TONIGHT/...

SHOWER AND THUNDERSTORM COVERAGE IS STILL EXPECTED TO INCREASE
TODAY AS BROAD MID LEVEL TROUGH EXTENDING FROM THE UPPER
MISSISSIPPI VALLEY TO THE SOUTHEAST COAST BECOMES MORE INFLUENTIAL
ON UPPER OHIO VALLEY WEATHER. MOISTURE SUPPLY IS ON THE INCREASE
WITH INFLUX VIA EASTERLY FLOW...AND CONVECTIVE TEMPERATURES ARE
PROJECTED TO DROP WITH EROSION OF THE RIDGE. HOWEVER...GIVEN THE
WEAK WIND FIELD OVER THE REGION...SHOWER AND THUNDERSTORM COVERAGE
IS EXPECTED TO REMAIN SCATTERED AND SEVERE POTENTIAL LIMITED TO
PULSE-TYPE WIND GUSTS AS UPDRAFTS COLLAPSE WITHOUT ORGANIZATION.

SHOWER CHANCES WILL BE DIMINISHED GRADUALLY TONIGHT AS DIURNAL
SUPPORT WANES.

GIVEN VARIANCES IN CLOUD COVER AND TIMING OF RAIN DEVELOPMENT...HIGHS
TODAY WILL RANGE FROM SEASONAL READINGS OVER EASTERN ZONES TO AS
MUCH AS 10 DEGREES ABOVE AVERAGE OVER WESTERN COUNTIES OF THE
COUNTY WARNING AREA. OVERNIGHT LOWS WILL ALSO BE WARM AS INCREASED
BOUNDARY LAYER MOISTURE WILL PRECLUDE A DRAMATIC DROP.
TEMPERATURES WERE FORECAST USING THE LATEST NAM NUMBERS.

&&

.SHORT TERM /TUESDAY THROUGH THURSDAY/...
MID WESTERN COLD FRONT IS PROJECTED TO PROGRESS EASTWARD TONIGHT.
LATEST ECMWF IS SLOWER TO EXIT THE UPPER TROUGH TO THE EAST AND
HOLDS DEEPER MOISTURE BACK ACROSS UPPER OHIO VALLEY INTO THURSDAY.
PREVIOUS FORECAST HAS THIS WELL HANDLED WITH HIGHEST POPS TUESDAY
WITH FRONT. CHANCE POPS WEDNESDAY INTO THURSDAY MAINLY ALONG THE
RIDGES BUT SLIGHT CHANCE POPS ACROSS MUCH OF THE REGION AS LOW
LEVEL MOISTURE WILL REMAIN. IF ECMWF SOLUTION IS MORE CORRECT MAY
NEED HIGHER POPS WEDNESDAY AND THURSDAY. TEMPERATURES WILL AVERAGE
ABOVE NORMAL ESPECIALLY OVERNIGHT. DEW POINTS HOVERING IN THE
UPPER 50S TO NEAR 60 WILL MAKE FOR MORE HUMID CONDITIONS.

&&

.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
00Z MODEL RUNS BRING RISING HEIGHTS ACROSS REGION BUT DIFFER ON
PLACEMENT AND INTENSITY OF DEVELOPING UPPER RIDGE. WILL KEEP
PREVIOUS TREND FOR ONLY ISOLATED POPS WITH ABOVE AVERAGE
TEMPERATURES APPROACHING 90 DEGREES AND SFC DEW POINTS IN THE LOW
TO MID 60S FOR THE START OF THE MEMORIAL DAY WEEKEND.

&&

.AVIATION /14Z MONDAY THROUGH FRIDAY/...
LOW PRESSURE WILL PULL ATLANTIC MOISTURE INTO THE AREA FROM THE
SOUTHEAST AND A FRONTAL BOUNDARY WILL APPROACH FROM THE WEST
LATER TODAY. ISOLATED SHOWERS AND THUNDERSTORMS WITH MVFR
RESTRICTIONS ARE POSSIBLE ACROSS THE TERMINALS LATE THIS
AFTERNOON AND EVENING. WITH ISOLATED COVERAGE...THUNDERSTORMS ARE
NOT MENTIONED IN THE TAFS AT THIS POINT. INCREASING LOW-LEVEL
MOISTURE MAKES IFR CONDITIONS LIKELY AFTER MIDNIGHT.

.OUTLOOK...TUESDAY THROUGH FRIDAY...
MOISTURE WILL INCREASE FROM THE EAST AS LOW PRESSURE MOVES UP THE
EASTERN SEABOARD. AN INCREASE IN LOW LEVEL MOISTURE MAY SET OFF
ISOLATED SHOWERS AND THUNDERSTORMS WITH RESTRICTIONS CONTINUING
THROUGH WEDNESDAY. SURFACE DEW POINTS WILL INCREASE THROUGH THE
PERIOD AND WILL LIKELY RESULT IN MVFR VISIBILITY RESTRICTIONS AT
MOST AIRPORT LOCATIONS DURING THE EARLY MORNING HOURS TUESDAY
THROUGH THURSDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$

15

000
FXUS61 KPHI 211337
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
937 AM EDT MON MAY 21 2012

.SYNOPSIS...
LOW PRESSURE ALONG THE EAST COAST WILL PERSIST THROUGH WEDNESDAY.
THEREAFTER...CENTRAL ATLANTIC HIGH PRESSURE WILL CONTINUE A
SOUTHERLY FLOW OF RELATIVELY HUMID AIR UP THE EAST COAST THURSDAY
INTO AT LEAST THE START OF THE MEMORIAL DAY WEEKEND. THE PASSAGE OF
ANY COOL FRONT HERE ON SUNDAY OR MONDAY IS HIGHLY UNCERTAIN AND IF
IT DOESN`T OCCUR...HOT WEATHER WILL ARRIVE FROM OHIO VALLEY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE LARGE HIGH PRESSURE SYSTEM OFF THE CANADIAN WATERS AND LOW
PRESSURE OFF THE SOUTHEAST U.S. COAST WILL CONTINUE THE ONSHORE FLOW
OVER THE AREA TODAY. WEAK DISTURBANCES EMBEDDED IN THE FLOW WILL
PROVIDE OPPORTUNITIES FOR SHOWERS ACROSS THE AREA TODAY. THE
TIMING OF THESE DISTURBANCES IS DIFFICULT...BUT THE WEATHER IS
NOT EXPECTED TO MAKE ANY GREAT IMPROVEMENTS TODAY.

AN AREA OF SHOWERS WITH EMBEDDED THUNDERSTORMS HAS BEEN SLOWLY
MOVING ACROSS NORTHERN NEW JERSEY AND WILL CONTINUE TO PUSH
NORTHWESTWARD OVER THE NEXT SEVERAL HOURS. ANOTHER AREA OF SHOWERS
WITH EMBEDDED THUNDERSTORMS IS SLOWLY MAKING ITS WAY TOWARD THE
COAST. WE HAVE ADDED ISOLATED THUNDER TO THE FORECAST AND CONTINUE
IT THROUGH THIS AFTERNOON FOR THE EASTERN 2/3RDS OF THE FORECAST
AREA. CHANCES FOR THUNDER WILL DECREASE AS WE HEAD TOWARD EVENING.
QPF WILL GENERALLY BE AROUND .50 INCH BUT LOCALLY HIGHER AMOUNTS
WILL REMAIN POSSIBLE IN HEAVIER SHOWERS.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM TUESDAY/...
NOT MUCH CHANGE TONIGHT. ONE SFC LOW WILL MOVE UP ALONG THE WATERS
TONIGHT...OTHER SHORTWAVES ALOFT WILL TRAVERSE THE AREA. POPS ARE
REDUCED BACK TO LOW LIKELY OR HIGH CHC POPS FOR TONIGHT. QPF AROUND
.10 TO .25 ACROSS THE AREA. WINDS BACK AROUND FROM ERLY TO NRLY AS
THE LOW MOVES NORTHWARD WELL EAST OF THE WATERS.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
TEMPERATURES: AVERAGE A BIT ABOVE NORMAL MOST OF THIS WORKWEEK
"POSSIBLY" TRENDING SUBSTANTIALLY ABOVE NORMAL THIS ENTIRE MEMORIAL
DAY WEEKEND...WITH THE CAVEAT THAT A BACKDOOR COLD FRONT MOVING
DOWN THROUGH NEW ENGLAND DOES NOT COME IN THE SIDE DOOR DOWN
HERE...IN OTHER WORDS...SLIDING SOUTHWEST THROUGH NEW JERSEY AND
DELAWARE.

THE HUMID CONDITIONS AND CONSIDERABLE CLOUDINESS MOST OF THIS WEEK
WILL FORCE NIGHTTIMES TO BE NOTABLY ABOVE NORMAL /5 TO 10 DEGREES
ON A DAILY BASIS/ WITH OUR DAYTIME MAXIMUM TEMPS CLOSER TO NORMAL.

WE ARE AWARE THE ECMWF IS CONSIDERABLY COOLER ON OUR DAYTIME MAX
TEMPS MUCH OF THIS WORKWEEK AND THEN WELL ABOVE OUR FORECAST FOR
NEXT SUNDAY AND MONDAY.

CLOUD COVER AND TIMING OF THE SHOWERY WEATHER CREATES THE UNCERTAINTY
OF FORECASTING MAX TEMPS THIS WORKWEEK AND THEN THE UNCERTAIN PASSAGE
OF ANY COLD FRONT HERE NEXT WEEKEND LIMITS EXPRESSION OF CONFIDENCE
REGARDING A POTENTIAL HEAT WAVE STARTING HERE SOMETIME DURING THE
MEMORIAL DAY WEEKEND.

500 MB: TROUGHING ALOFT IN THE EASTERN UNITED STATES PRODUCES A
PERSISTENTLY MORE HUMID AND INTERMITTENTLY SHOWERY REGIME HERE
THIS WEEK. THE TROUGH WILL BE REPLACED BY STRONG RIDGING...AND
DRYING ALOFT...RESULTING IN HEAT WAVE CONDITIONS OF 90 DEGREE HEAT
IN THE MIDWEST AND SOUTHERN UNITED STATES EVENTUALLY BUILDING
NORTHEASTWARD TOWARD OR INTO OUR AREA DURING THE MEMORIAL DAY
WEEKEND.


THE DAILIES...

TUESDAY THROUGH FRIDAY...WEAK FORCING AND OCCASIONAL INSTABILITY
WILL PRODUCE BANDS OF SHOWERS. SINCE THE STEERING WINDS ALOFT WILL
BE VERY LIGHT...THE BANDS OF CONVECTION WILL BE SLOW MOVING...
PERMITTING BANDS OR POCKETS OF HEAVY RAINFALL.  DAILY DETAILS CANNOT
BE RELIABLY OFFERED SO A BLEND OF 00Z/21 NCEP MOS GUIDANCE WAS USED
TO DEVELOP THE FCST ELEMENTS. WE NOTE THE ECMWF IS COOLER THAN OUR
330 AM DETERMINISTIC FCST THIS WEEK...BUT I THINK THIS IS LARGELY
PREDICATED ON THEIR CONSTANCY OF SHOWERY WEATHER. USUALLY IN THESE
PATTERNS THERE ARE LARGE CHUNKS OF TIME WHEN ITS NOT RAINING.
CONFIDENCE IMAGERY FOCUSED ON GFS 2M TEMPS FROM FSU EXPRESSES
ABOVE AVERAGE CONFIDENCE IN THE GFS 2M TEMP FCST THIS WEEK...IN
OTHER WORDS LEANING WARMER WHEN COMPARING THE 00Z/21 GFS TO THE
00Z/21 ECMWF IS THE WAY TO THINK ATTM.

MEMORIAL DAY WEEKEND...ON THE OTHER HAND...A DRYING OUT DOWN TO
800 MB AND HEATING UP IS FORECAST THIS 3 DAY PERIOD AND HERE THE
GFS 2M TEMP FCST IS EXPRESSING LESS THAN AVERAGE CONFIDENCE FOR
THIS 00Z/21 CYCLE. THAT SUGGESTS TO ME THAT THE ECMWF AND UKMET
ARE ON THE RIGHT TRACK SENDING 90 DEGREE HEAT INTO THE MID
ATLANTIC STATES BY SUNDAY OR MONDAY. THERE IS MODEL SPREAD ON THE
SOLUTION WHICH MEANS WE CANT BE SURE HOW WARM IT BECOME. THERE
STILL MAY BE CONSIDERABLE MOISTURE BELOW 800MB WHICH COULD LIMIT
REALIZING THE POTENTIAL THAT 850 MB TEMPS WILL BE OFFERING.

IN ANY CASE...THE SHOWERY WEATHER OF THIS WORK WEEK SHOULD BE
ALMOST NON EXISTENT THIS WEEKEND DUE TO SUBSIDENCE ASSOCIATED
WITH THE VERY STRONG RIDGE DEVELOPING ALOFT.

&&

.AVIATION /14Z MONDAY THROUGH FRIDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.

MOST LOCATIONS ARE IFR OR LIFR EARLY THIS MORNING, WITH THE
EXCEPTION OF KABE, WHICH IS MVFR.  EXPECT THE REDUCED CIGS TO
CONTINUE THRU THE DAY.  CONFIDENCE IS VERY LOW ON IMPROVEMENT ACRS
THE SRN TAF SITES LATER THIS MORNING.

A LARGE AREA OF PRECIP IS LURKING OFF THE NJ COAST AND MOVING SLOWLY
WWD.  EARLIER THINKING WAS THAT THIS RAIN WOULD MOVE OVER THE TAF
SITES FROM KACY TO KTTN AND COULD HELP RAISE CIGS TO PERHAPS MVFR BY
LATER THIS MORNING.  UNFORTUNATELY, THIS PRECIP IS NOT MOVG VERY
MUCH AT ALL AND WITHOUT IT, CIGS ARE PRETTY MUCH GOING TO STAY WHERE
THEY ARE.  THERE HAVE BEEN SOME SHOWERS AHEAD OF THE MAIN SURGE BUT
THESE HAVE BEEN HAVING A HARD TIME MAKING IT WWD AS WELL.  SO,
FUTURE TAF AMENDMENTS WILL LIKELY PUSH BACK AND POSSIBLY ELIMINATE
THE CIG IMPROVEMENTS FCST LATER THIS MORNING, SUBJECT TO RADAR
TRENDS AT THAT TIME.

OVERALL, POOR FLYING CONDS ARE EXPECTED TO CONTINUE.  SCT TSRA CAN
NOT BE RULED OUT FOR AREA ARPTS, ESPECIALLY ACRS NJ, WHICH ONLY
FURTHER COMPLICATES MATTERS.  CHC OF OCCURRENCE AT ANY INDIVIDUAL
SITE IS LOW BUT ITS THERE, NONETHELESS.

OUTLOOK...
TUESDAY THROUGH FRIDAY...MVFR OR IFR CONDS LATER EACH NIGHT AND
EARLY EACH DAY IN ST/FOG BECOMES VFR CIGS MIDDAY INTO THE EVENING.
LOCAL MVFR OR IFR CONDS IN SCATTERED SHOWERS OR EVEN A TSTM. LIGHT
WIND...TENDING TO BE MOSTLY SOUTHEAST TO SOUTH.

&&

.MARINE...
ONGOING SCA CONDITIONS WILL CONTINUE ON THE OCEAN FOR SEVERAL
PERIODS (BEYOND THE SHORT TERM) WHILE EITHER LOW END SCA OR
MARGINALLY CLOSE TO SCA CONDITIONS FOR THE LOWER DEL BAY OVER THE
NEXT FEW DAYS. CHOSE TO EXTEND THE PREVIOUS SCA FLAG FOR THE LOWER
BAY UNTIL 16Z...IT MAY BE EXTENDED BEYOND THAT CLOSE TO EXPIRATION
TIME...UNLESS THE WINDS SHOW SOME DOWNWARD TREND THAT LOOKS TO HOLD.
SCA WINDS AND SEAS WILL NOT EXTEND INTO NRN DEL BAY. SHOWERY
CONDITIONS WITH A FEW TSTMS THIS MORNING...MOSTLY OVER THE SRN
COASTAL WATERS.


OUTLOOK...
TUESDAY THROUGH FRIDAY.

WIND SPEEDS ARE FORECAST TO REMAIN BELOW THE SMALL CRAFT ADVISORY
CRITERION.

WAVE HEIGHTS ON OUR OCEAN WATERS MAY BE FLIRTING WITH HAZARDOUS
SEAS CRITERIA AT TIMES...ESPECIALLY TUESDAY...BUT FOR NOW...OTHER
THAN A 3 TO 4 FT SE SWELL OF 8 SECONDS...MUCH OF THIS TIME SHOULD
BE SCA FREE.

&&

.HYDROLOGY...
OCCASIONAL INSTABILITY IN ASSOCIATION WITH PERSISTENTLY HIGH HUMIDITY
AND COOL TROUGHING ALOFT WILL PROBABLY YIELD A COUPLE OF SWATHS OF
STORM TOTALS EXCEEDING 3 INCHES THIS WEEK. MOST OF THE AREA SHOULD
BE DOUSED BY AT LEAST HALF AN INCH THIS WEEK...INCLUDING AMOUNTS
THAT BEGAN THIS PAST SUNDAY EVENING. IF THERE WERE TO BE ANY SMALL
STREAM FLOOD PROBLEMS...IT WOULD MORE LIKELY OCCUR IN EASTERN
PENNSYLVANIA OR NORTHEAST NEW JERSEY WHERE GRIDDED FLASH FLOOD
GUIDANCE SHOWS GREATER VULNERABILITY. 1 HR FFG NEAR 1.3 INCHES AND
6 TO 24 HR GUIDANCE IS CURRENTLY NEAR 1.9 INCHES. THAT WOULD PLACE
MONTGOMERY...WITH THE NEARBY CHESTER COUNTY PA BORDER AND CENTRAL
MORRIS COUNTY NJ AS SEEMINGLY MOST VULNERABLE.

&&

.RIP CURRENTS...
WHILE THE ONSHORE FLOW WILL PERSIST TODAY, IT IS FORECAST TO NOT
BE AS STRONG AS YESTERDAY. SEAS ARE LESS THAN YESTERDAY BY 2 FEET
BUT THE SE SWELL IS STILL NEAR 5 FEET WITH AN 8 SECOND PERIOD. BASED
ON THIS, WE PROBABLY WILL HAVE A MODERATE RISK OF RIP CURRENTS
TODAY.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT TUESDAY FOR ANZ452>455.
     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 AM EDT TUESDAY
     FOR ANZ450-451.
     SMALL CRAFT ADVISORY UNTIL NOON EDT TODAY FOR ANZ431.

&&

$$
SYNOPSIS...DRAG
NEAR TERM...MEOLA/O`HARA
SHORT TERM...O`HARA
LONG TERM...DRAG
AVIATION...DRAG/NIERENBERG
MARINE...DRAG/O`HARA
HYDROLOGY...
RIP CURRENTS...

000
FXUS61 KPHI 211329
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ




&&

.AVIATION /07Z THURSDAY THROUGH MONDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.

MOST LOCATIONS ARE IFR OR LIFR EARLY THIS MORNING, WITH THE
EXCEPTION OF KABE, WHICH IS MVFR.  EXPECT THE REDUCED CIGS TO
CONTINUE THRU THE DAY.  CONFIDENCE IS VERY LOW ON IMPROVEMENT ACRS
THE SRN TAF SITES LATER THIS MORNING.

A LARGE AREA OF PRECIP IS LURKING OFF THE NJ COAST AND MOVING SLOWLY
WWD.  EARLIER THINKING WAS THAT THIS RAIN WOULD MOVE OVER THE TAF
SITES FROM KACY TO KTTN AND COULD HELP RAISE CIGS TO PERHAPS MVFR BY
LATER THIS MORNING.  UNFORTUNATELY, THIS PRECIP IS NOT MOVG VERY
MUCH AT ALL AND WITHOUT IT, CIGS ARE PRETTY MUCH GOING TO STAY WHERE
THEY ARE.  THERE HAVE BEEN SOME SHOWERS AHEAD OF THE MAIN SURGE BUT
THESE HAVE BEEN HAVING A HARD TIME MAKING IT WWD AS WELL.  SO,
FUTURE TAF AMENDMENTS WILL LIKELY PUSH BACK AND POSSIBLY ELIMINATE
THE CIG IMPROVEMENTS FCST LATER THIS MORNING, SUBJECT TO RADAR
TRENDS AT THAT TIME.

OVERALL, POOR FLYING CONDS ARE EXPECTED TO CONTINUE.  SCT TSRA CAN
NOT BE RULED OUT FOR AREA ARPTS, ESPECIALLY ACRS NJ, WHICH ONLY
FURTHER COMPLICATES MATTERS.  CHC OF OCCURRENCE AT ANY INDIVIDUAL
SITE IS LOW BUT ITS THERE, NONETHELESS.




&&

000
FXUS61 KCTP 211200
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
748 AM EDT MON MAY 21 2012

.SYNOPSIS...
AN UPPER LOW OVER THE SOUTHEAST COAST WILL OPEN UP AND LIFT
NORTHEAST TODAY AND TONIGHT. A DEEPENING SHORTWAVE WILL SLOW DOWN
AND CUT OFF OVR THE CENTRAL APPALACHIANS DURING THE MIDDLE OF THE
WEEK. PENNSYLVANIA WILL BE ON THE EDGE OF THE REBUILDING UPPER RIDGE
ACROSS THE OHIO VALLEY BY THE END OF NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPPER LOW OVER THE CAROLINA COAST WILL LIFT NORTH ALONG THE E
COAST DURING THE NEXT 24HRS. ASSOCIATED MOIST...EASTERLY LL JET AND
UPPER LVL DIVERGENCE PRECEDING THE UPPER LOW WILL BRING SHOWERS
TO MOST OF CENTRAL PA TODAY. RADAR SHOWS SCT SHOWERS HAVE ALREADY
OVERSPREAD THE LOWER SUSQ VALLEY AS OF 09Z AND LATEST RUC AND 4KM
NAM SUGGEST NORTHERN EDGE OF SHOWERS/DRIZZLE WILL REACH FROM ARND
JST TO IPT BY LATE MORNING.

CLOUD COVER...PRECIP AND EASTERLY FLOW OFF THE ATLANTIC WILL
RESULT IN MUCH COOLER TEMPS TODAY WITH MAXIMUMS ONLY ARND 70F.
BLEND OF OPER AND ENSEMBLE QPF INDICATES LIKELY RAINFALL AMTS
TODAY OF BTWN 0.1 AND 0.2 INCHES.

DOWNSLOPING SE FLOW WILL RESULT IN PARTIAL SUNSHINE AND A
SOMEWHAT WARMER MONDAY OVR WARREN COUNTY...WHERE A LATE DAY
TSRA IS POSSIBLE. OPER GFS/NAM INDICATE CAPE VALUES NR 1000JK-1
ACROSS WARREN CO BY THIS EVENING. FURTHER EAST...A COOLER MORE
STABLE EASTERLY FLOW WILL LIKELY PRECLUDE THUNDER.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
SCT SHRA WILL CONTINUE TO FALL OVER CENTRAL PA TONIGHT...AS MOIST
EASTERLY LL JET AND UPPER LVL DIVERGENCE REMAIN OVR THE AREA IN
ADVANCE OF UPPER LOW. A GENERAL DECREASE IN SHOWER ACTIVITY IS
EXPECTED LATE TONIGHT AS UPPER LOW OPENS UP AND LIFTS NE. BIGGER
STORY LATE TONIGHT COULD BE AREAS OF POTENTIALLY DENSE FOG. PLENTY
OF LL MOISTURE AND A NEARLY CALM WIND WILL BE FAVORABLE FOR FOG.

AS E COAST UPPER LOW OPENS UP AND LIFTS INTO THE CANADIAN
MARITIMES...UPSTREAM SHORTWAVE WILL DEEPEN AND CUT OFF OVR THE
TENN VALLEY ON TUESDAY. LG SCALE FORCING AHEAD OF THIS FEATURE
WILL PRODUCE MORE SHRA/TSRA TUESDAY. GEFS/SREF DATA BOTH SUGGEST
BEST CHC OF SHRA/TSRA WILL BE ALONG THE SPINE OF THE APPALACHIANS.
OVERCAST SKIES AND VERY LGT WINDS ALOFT SUGGEST THERE WILL BE VERY
LITTLE THREAT OF SVR WX. BLEND OF GEFS/SREF QPF RANGES FROM 0.2 TO
0.3 INCHES TONIGHT AND TUESDAY.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
RELATIVELY GOOD AGREEMENT AMONG MED RANGE GUIDANCE LATER THIS
WEEK...ALL OF WHICH INDICATES UPPER LOW SLOWLY LIFTING NORTH ALONG
THE CENTRAL APPALACHIANS. THIS SCENARIO SUPPORTS THE CHC OF
DIURNALLY ENHANCED SHRA/TSRA WED-THU AND POSSIBLY EVEN FRIDAY. NEARLY
ALL MDL DATA TRACKS TS ALBERTO WELL EAST OFF THE MID ATLANTIC
COAST TUE NIGHT WITH NO DIRECT IMPACT ON PA.

TEMPS THIS WEEK LOOK TO BE ABOVE NORMAL...MAINLY DUE TO WARM
OVERNIGHT LOWS. DEEP SOUTHERLY FLOW AHEAD OF UPPER LOW WILL
TRANSPORT ABOVE NORMAL MOISTURE NORTH ALONG THE E COAST...RESULTING
IN THE WARM NIGHTS.

EVEN WARMER WX APPEARS VERY LIKELY BY NEXT WEEKEND WHEN ALL MDL
DATA INDICATES A BUILDING UPPER LVL RIDGE OVER THE OHIO VALLEY.
HOWEVER...PA MAY BE ON PERIPHERY OF THIS FEATURE...PLACING AT
LEAST NORTHERN PA IN RING OF FIRE WITH CHC OF PM CONVECTION.

&&

.AVIATION /12Z MONDAY THROUGH FRIDAY/...
AN UPPER LOW OVER THE SOUTHEAST COAST WILL OPEN UP AND LIFT
NORTHEAST TODAY AND TONIGHT...AND AN INCREASING LL JET WILL
BRING MOIST SOUTHEAST FLOW AND GENERALLY POOR FLYING CONDITIONS
TO THE REGION OVER THE NEXT SEVERAL DAYS.

INCREASING MOISTURE HAS ALREADY RESULTED IN LOWERING CIGS ACROSS
MUCH OF CENTRAL PA. IFR CIGS PREVALENT IN THE LOWER SUSQ...WITH
MVFR GRADUALLY SPREADING NW ACROSS CENTRAL MTNS. SHOWERS WILL ALSO
INCREASE FROM THE SE DURING THE DAY TODAY...WITH NORTHERN EDGE OF
SHOWERS REACHING FROM AROUND JST-UNV-IPT BY LATE MORNING.

CIGS DETERIORATE FURTHER OVERNIGHT...BECOMING IFR AS AN UPPER
LEVEL TROF APPROACHES FROM THE GREAT LAKES.

OUTLOOK...
MON NIGHT-WED...WIDESPREAD MVFR/IFR CIGS AND VSBYS LIKELY IN
SHOWERS AND SCT TSRA.
THU...PRIMARILY VFR. SCT SHRA/TSTM POSS MAINLY SE.
FRI...PRIMARILY VFR. ISOLD SHRA/TSTM POSS MAINLY SE.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...FITZGERALD
NEAR TERM...FITZGERALD
SHORT TERM...FITZGERALD
LONG TERM...FITZGERALD/MARTIN
AVIATION...RXR

000
FXUS61 KCTP 211148
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
748 AM EDT MON MAY 21 2012

.SYNOPSIS...
AN UPPER LOW OVER THE SOUTHEAST COAST WILL OPEN UP AND LIFT
NORTHEAST TODAY AND TONIGHT. A DEEPENING SHORTWAVE WILL SLOW DOWN
AND CUT OFF OVR THE CENTRAL APPALACHIANS DURING THE MIDDLE OF THE
WEEK. PENNSYLVANIA WILL BE ON THE EDGE OF A BUILDING 500 HPA RIDGE
ACROSS THE OHIO VALLEY BY THE END OF NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPPER LOW OVER THE CAROLINA COAST WILL LIFT NORTH ALONG THE E
COAST DURING THE NEXT 24HRS. ASSOCIATED MOIST...EASTERLY LL JET AND
UPPER LVL DIVERGENCE PRECEDING THE UPPER LOW WILL BRING SHOWERS
TO MOST OF CENTRAL PA TODAY. RADAR SHOWS SCT SHOWERS HAVE ALREADY
OVERSPREAD THE LOWER SUSQ VALLEY AS OF 09Z AND LATEST RUC AND 4KM
NAM SUGGEST NORTHERN EDGE OF SHOWERS/DRIZZLE WILL REACH FROM ARND
JST TO IPT BY LATE MORNING.

CLOUD COVER...PRECIP AND EASTERLY FLOW OFF THE ATLANTIC WILL
RESULT IN MUCH COOLER TEMPS TODAY WITH MAXIMUMS ONLY ARND 70F.
BLEND OF OPER AND ENSEMBLE QPF INDICATES LIKELY RAINFALL AMTS
TODAY OF BTWN 0.1 AND 0.2 INCHES.

DOWNSLOPING SE FLOW WILL RESULT IN PARTIAL SUNSHINE AND A
SOMEWHAT WARMER MONDAY OVR WARREN COUNTY...WHERE A LATE DAY
TSRA IS POSSIBLE. OPER GFS/NAM INDICATE CAPE VALUES NR 1000JK-1
ACROSS WARREN CO BY THIS EVENING. FURTHER EAST...A COOLER MORE
STABLE EASTERLY FLOW WILL LIKELY PRECLUDE THUNDER.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
SCT SHRA WILL CONTINUE TO FALL OVER CENTRAL PA TONIGHT...AS MOIST
EASTERLY LL JET AND UPPER LVL DIVERGENCE REMAIN OVR THE AREA IN
ADVANCE OF UPPER LOW. A GENERAL DECREASE IN SHOWER ACTIVITY IS
EXPECTED LATE TONIGHT AS UPPER LOW OPENS UP AND LIFTS NE. BIGGER
STORY LATE TONIGHT COULD BE AREAS OF POTENTIALLY DENSE FOG. PLENTY
OF LL MOISTURE AND A NEARLY CALM WIND WILL BE FAVORABLE FOR FOG.

AS E COAST UPPER LOW OPENS UP AND LIFTS INTO THE CANADIAN
MARITIMES...UPSTREAM SHORTWAVE WILL DEEPEN AND CUT OFF OVR THE
TENN VALLEY ON TUESDAY. LG SCALE FORCING AHEAD OF THIS FEATURE
WILL PRODUCE MORE SHRA/TSRA TUESDAY. GEFS/SREF DATA BOTH SUGGEST
BEST CHC OF SHRA/TSRA WILL BE ALONG THE SPINE OF THE APPALACHIANS.
OVERCAST SKIES AND VERY LGT WINDS ALOFT SUGGEST THERE WILL BE VERY
LITTLE THREAT OF SVR WX. BLEND OF GEFS/SREF QPF RANGES FROM 0.2 TO
0.3 INCHES TONIGHT AND TUESDAY.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
RELATIVELY GOOD AGREEMENT AMONG MED RANGE GUIDANCE LATER THIS
WEEK...ALL OF WHICH INDICATES UPPER LOW SLOWLY LIFTING NORTH ALONG
THE CENTRAL APPALACHIANS. THIS SCENARIO SUPPORTS THE CHC OF
DIURNALLY ENHANCED SHRA/TSRA WED-THU AND POSSIBLY EVEN FRIDAY. NEARLY
ALL MDL DATA TRACKS TS ALBERTO WELL EAST OFF THE MID ATLANTIC
COAST TUE NIGHT WITH NO DIRECT IMPACT ON PA.

TEMPS THIS WEEK LOOK TO BE ABOVE NORMAL...MAINLY DUE TO WARM
OVERNIGHT LOWS. DEEP SOUTHERLY FLOW AHEAD OF UPPER LOW WILL
TRANSPORT ABOVE NORMAL MOISTURE NORTH ALONG THE E COAST...RESULTING
IN THE WARM NIGHTS.

EVEN WARMER WX APPEARS VERY LIKELY BY NEXT WEEKEND WHEN ALL MDL
DATA INDICATES A BUILDING UPPER LVL RIDGE OVER THE OHIO VALLEY.
HOWEVER...PA MAY BE ON PERIPHERY OF THIS FEATURE...PLACING AT
LEAST NORTHERN PA IN RING OF FIRE WITH CHC OF PM CONVECTION.

&&

.AVIATION /12Z MONDAY THROUGH FRIDAY/...
AN UPPER LOW OVER THE SOUTHEAST COAST WILL OPEN UP AND LIFT
NORTHEAST TODAY AND TONIGHT...AND AN INCREASING LL JET WILL
BRING MOIST SOUTHEAST FLOW AND GENERALLY POOR FLYING CONDITIONS
TO THE REGION OVER THE NEXT SEVERAL DAYS.

INCREASING MOISTURE HAS ALREADY RESULTED IN LOWERING CIGS ACROSS
MUCH OF CENTRAL PA. IFR CIGS PREVALENT IN THE LOWER SUSQ...WITH
MVFR GRADUALLY SPREADING NW ACROSS CENTRAL MTNS. SHOWERS WILL ALSO
INCREASE FROM THE SE DURING THE DAY TODAY...WITH NORTHERN EDGE OF
SHOWERS REACHING FROM AROUND JST-UNV-IPT BY LATE MORNING.

CIGS DETERIORATE FURTHER OVERNIGHT...BECOMING IFR AS AN UPPER
LEVEL TROF APPROACHES FROM THE GREAT LAKES.

OUTLOOK...
MON NIGHT-WED...WIDESPREAD MVFR/IFR CIGS AND VSBYS LIKELY IN
SHOWERS AND SCT TSRA.
THU...PRIMARILY VFR. SCT SHRA/TSTM POSS MAINLY SE.
FRI...PRIMARILY VFR. ISOLD SHRA/TSTM POSS MAINLY SE.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...FITZGERALD
NEAR TERM...FITZGERALD
SHORT TERM...FITZGERALD
LONG TERM...FITZGERALD/MARTIN
AVIATION...RXR

000
FXUS61 KPBZ 211118
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
718 AM EDT MON MAY 21 2012

.SYNOPSIS...
RAIN CHANCES WILL INCREASE EARLY THIS WEEK AS A COLD FRONT
SLOWLY APPROACHES FROM THE WEST AND AS LOW PRESSURE MOVES UP THE
EAST COAST.

&&

.NEAR TERM /THROUGH TONIGHT/...
NO CHANGES NEEDED FOR THE POST DAWN UPDATE OTHER THAN TWEAKS TO
HOURLY TRENDS.

RIDGE AXIS WILL WEAKEN ACROSS REGION TODAY AND WITH LOW PRESSURE
OVER VIRGINIA SLOWLY MOVING NORTHWEST, DEEPER MOISTURE WILL SPREAD
ACROSS THE RIDGES. A COLD FRONT NEAR THE INDIANA AND OHIO BORDER
WILL EDGE EAST AS WELL. THIS WILL BRING CHANCE POPS MAINLY THIS
AFTERNOON WITH HIGHER POPS ACROSS EASTERN 2/3RDS OF REGION.
LOWERED MAX TEMPS CLOSER TO NEW MAV GUIDANCE WHICH SEEMS
REASONABLE.

&&

.SHORT TERM /TUESDAY THROUGH THURSDAY/...
COLD FRONT WILL CONTINUE TO PROGRESS EAST MONDAY NIGHT AND MODELS IN
A BIT OF DISARRAY ON PLACEMENT OF UPPER TROUGH AS SURFACE LOW MOVES
OFF THE NEW ENGLAND COAST THROUGH PERIOD. NEW ECMWF SLOWER TO EXIT
UPPER TROUGH TO THE EAST AND HOLDS DEEPER MOISTURE BACK ACROSS UPPER
OHIO VALLEY INTO THURSDAY. PREVIOUS FORECAST HAS THIS WELL HANDLED
WITH HIGHEST POPS TUESDAY WITH FRONT. CHANCE POPS WEDNESDAY INTO
THURSDAY MAINLY ALONG THE RIDGES BUT SLIGHT CHANCE POPS ACROSS
MUCH OF THE REGION AS LOW LEVEL MOISTURE WILL REMAIN. IF ECMWF
SOLUTION IS MORE CORRECT MAY NEED HIGHER POPS WEDNESDAY AND
THURSDAY. TEMPERATURES WILL AVERAGE ABOVE NORMAL ESPECIALLY
OVERNIGHT. DEW POINTS HOVERING IN THE UPPER 50S TO NEAR 60 WILL
MAKE FOR MORE HUMID CONDITIONS.

&&

.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
00Z MODEL RUNS BRING RISING HEIGHTS ACROSS REGION BUT DIFFER ON
PLACEMENT AND INTENSITY OF DEVELOPING UPPER RIDGE. WILL KEEP
PREVIOUS TREND FOR ONLY ISOLATED POPS WITH ABOVE AVERAGE
TEMPERATURES APPROACHING 90 DEGREES AND SFC DEW POINTS IN THE LOW
TO MID 60S FOR THE START OF THE MEMORIAL DAY WEEKEND.

&&

.AVIATION /11Z MONDAY THROUGH FRIDAY/...
LOW PRESSURE WILL PULL ATLANTIC MOISTURE INTO THE AREA FROM THE
SOUTHEAST AND A FRONTAL BOUNDARY WILL APPROACH FROM THE WEST
LATER TODAY. ISOLATED SHOWERS AND THUNDERSTORMS WITH MVFR
RESTRICTIONS ARE POSSIBLE ACROSS THE TERMINALS LATE THIS
AFTERNOON AND EVENING. WITH ISOLATED COVERAGE...THUNDERSTORMS ARE
NOT MENTIONED IN THE TAFS AT THIS POINT. INCREASING LOW-LEVEL
MOISTURE MAKES IFR CONDITIONS LIKELY AFTER MIDNIGHT.

.OUTLOOK...TUESDAY THROUGH FRIDAY...
MOISTURE WILL INCREASE FROM THE EAST AS LOW PRESSURE MOVES UP THE
EASTERN SEABOARD. AN INCREASE IN LOW LEVEL MOISTURE MAY SET OFF
ISOLATED SHOWERS AND THUNDERSTORMS WITH RESTRICTIONS CONTINUING
THROUGH WEDNESDAY. SURFACE DEW POINTS WILL INCREASE THROUGH THE
PERIOD AND WILL LIKELY RESULT IN MVFR VISIBILITY RESTRICTIONS AT
MOST AIRPORT LOCATIONS DURING THE EARLY MORNING HOURS TUESDAY
THROUGH THURSDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$

000
FXUS61 KPBZ 211113
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
713 AM EDT MON MAY 21 2012

.SYNOPSIS...
RAIN CHANCES WILL INCREASE EARLY THIS WEEK AS A COLD FRONT
SLOWLY APPROACHES FROM THE WEST AND AS LOW PRESSURE MOVES UP THE
EAST COAST.

&&

.NEAR TERM /THROUGH TONIGHT/...

NO CHANGES NEEDED FOR THE POST DAWN UPDATE OTHER THAN TWEAKS TO
HOURLY TRENDS.

RIDGE AXIS WILL WEAKEN ACROSS REGION TODAY AND WITH LOW PRESSURE
OVER VIRGINIA SLOWLY MOVING NORTHWEST, DEEPER MOISTURE WILL SPREAD
ACROSS THE RIDGES. A COLD FRONT NEAR THE INDIANA AND OHIO BORDER
WILL EDGE EAST AS WELL. THIS WILL BRING CHANCE POPS MAINLY THIS
AFTERNOON WITH HIGHER POPS ACROSS EASTERN 2/3RDS OF REGION.
LOWERED MAX TEMPS CLOSER TO NEW MAV GUIDANCE WHICH SEEMS
REASONABLE.

&&

.SHORT TERM /TUESDAY THROUGH THURSDAY/...
COLD FRONT WILL CONTINUE TO PROGRESS EAST MONDAY NIGHT AND MODELS IN
A BIT OF DISARRAY ON PLACEMENT OF UPPER TROUGH AS SURFACE LOW MOVES
OFF THE NEW ENGLAND COAST THROUGH PERIOD. NEW ECMWF SLOWER TO EXIT
UPPER TROUGH TO THE EAST AND HOLDS DEEPER MOISTURE BACK ACROSS UPPER
OHIO VALLEY INTO THURSDAY. PREVIOUS FORECAST HAS THIS WELL HANDLED
WITH HIGHEST POPS TUESDAY WITH FRONT. CHANCE POPS WEDNESDAY INTO
THURSDAY MAINLY ALONG THE RIDGES BUT SLIGHT CHANCE POPS ACROSS
MUCH OF THE REGION AS LOW LEVEL MOISTURE WILL REMAIN. IF ECMWF
SOLUTION IS MORE CORRECT MAY NEED HIGHER POPS WEDNESDAY AND
THURSDAY. TEMPERATURES WILL AVERAGE ABOVE NORMAL ESPECIALLY
OVERNIGHT. DEW POINTS HOVERING IN THE UPPER 50S TO NEAR 60 WILL
MAKE FOR MORE HUMID CONDITIONS.

&&

.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
00Z MODEL RUNS BRING RISING HEIGHTS ACROSS REGION BUT DIFFER ON
PLACEMENT AND INTENSITY OF DEVELOPING UPPER RIDGE. WILL KEEP
PREVIOUS TREND FOR ONLY ISOLATED POPS WITH ABOVE AVERAGE
TEMPERATURES APPROACHING 90 DEGREES AND SFC DEW POINTS IN THE LOW
TO MID 60S FOR THE START OF THE MEMORIAL DAY WEEKEND.

&&

.AVIATION /11Z MONDAY THROUGH FRIDAY/...
LOW PRESSURE WILL PULL ATLANTIC MOISTURE INTO THE AREA FROM THE
SOUTHEAST AND A FRONTAL BOUNDARY WILL APPROACH FROM THE WEST
LATER TODAY. ISOLATED SHOWERS AND THUNDERSTORMS WITH MVFR
RESTRICTIONS ARE POSSIBLE ACROSS THE TERMINALS LATE THIS
AFTERNOON AND EVENING. WITH ISOLATED COVERAGE...THUNDERSTORMS ARE
NOT MENTIONED IN THE TAFS AT THIS POINT.

.OUTLOOK...MONDAY NIGHT THROUGH FRIDAY...
MOISTURE WILL INCREASE FROM THE EAST AS LOW PRESSURE MOVES UP THE
EASTERN SEABOARD. AN INCREASE IN LOW LEVEL MOISTURE MAY SET OFF
ISOLATED SHOWERS AND THUNDERSTORMS WITH RESTRICTIONS TONIGHT
THROUGH WEDNESDAY. SURFACE DEW POINTS WILL INCREASE THROUGH THE
PERIOD AND WILL LIKELY RESULT IN MVFR VISIBILITY RESTRICTIONS AT
MOST AIRPORT LOCATIONS DURING THE EARLY MORNING HOURS TUESDAY
THROUGH THURSDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$

15

000
FXUS61 KCTP 210950
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
550 AM EDT MON MAY 21 2012

.SYNOPSIS...
AN UPPER LOW OVER THE SOUTHEAST COAST WILL OPEN UP AND LIFT
NORTHEAST TODAY AND TONIGHT. A DEEPENING SHORTWAVE WILL SLOW DOWN
AND CUT OFF OVR THE CENTRAL APPALACHIANS DURING THE MIDDLE OF THE
WEEK. PENNSYLVANIA WILL BE ON THE EDGE OF A BUILDING 500 HPA RIDGE
ACROSS THE OHIO VALLEY BY THE END OF NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPPER LOW OVER THE CAROLINA COAST WILL LIFT NORTH ALONG THE E
COAST DURING THE NEXT 24HRS. ASSOCIATED MOIST...EASTERLY LL JET AND
UPPER LVL DIVERGENCE PRECEDING THE UPPER LOW WILL BRING SHOWERS
TO MOST OF CENTRAL PA TODAY. RADAR SHOWS SCT SHOWERS HAVE ALREADY
OVERSPREAD THE LOWER SUSQ VALLEY AS OF 09Z AND LATEST RUC AND 4KM
NAM SUGGEST NORTHERN EDGE OF SHOWERS/DRIZZLE WILL REACH FROM ARND
JST TO IPT BY LATE MORNING.

CLOUD COVER...PRECIP AND EASTERLY FLOW OFF THE ATLANTIC WILL
RESULT IN MUCH COOLER TEMPS TODAY WITH MAXIMUMS ONLY ARND 70F.
BLEND OF OPER AND ENSEMBLE QPF INDICATES LIKELY RAINFALL AMTS
TODAY OF BTWN 0.1 AND 0.2 INCHES.

DOWNSLOPING SE FLOW WILL RESULT IN PARTIAL SUNSHINE AND A
SOMEWHAT WARMER MONDAY OVR WARREN COUNTY...WHERE A LATE DAY
TSRA IS POSSIBLE. OPER GFS/NAM INDICATE CAPE VALUES NR 1000JK-1
ACROSS WARREN CO BY THIS EVENING. FURTHER EAST...A COOLER MORE
STABLE EASTERLY FLOW WILL LIKELY PRECLUDE THUNDER.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
SCT SHRA WILL CONTINUE TO FALL OVER CENTRAL PA TONIGHT...AS MOIST
EASTERLY LL JET AND UPPER LVL DIVERGENCE REMAIN OVR THE AREA IN
ADVANCE OF UPPER LOW. A GENERAL DECREASE IN SHOWER ACTIVITY IS
EXPECTED LATE TONIGHT AS UPPER LOW OPENS UP AND LIFTS NE. BIGGER
STORY LATE TONIGHT COULD BE AREAS OF POTENTIALLY DENSE FOG. PLENTY
OF LL MOISTURE AND A NEARLY CALM WIND WILL BE FAVORABLE FOR FOG.

AS E COAST UPPER LOW OPENS UP AND LIFTS INTO THE CANADIAN
MARITIMES...UPSTREAM SHORTWAVE WILL DEEPEN AND CUT OFF OVR THE
TENN VALLEY ON TUESDAY. LG SCALE FORCING AHEAD OF THIS FEATURE
WILL PRODUCE MORE SHRA/TSRA TUESDAY. GEFS/SREF DATA BOTH SUGGEST
BEST CHC OF SHRA/TSRA WILL BE ALONG THE SPINE OF THE APPALACHIANS.
OVERCAST SKIES AND VERY LGT WINDS ALOFT SUGGEST THERE WILL BE VERY
LITTLE THREAT OF SVR WX. BLEND OF GEFS/SREF QPF RANGES FROM 0.2 TO
0.3 INCHES TONIGHT AND TUESDAY.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
RELATIVELY GOOD AGREEMENT AMONG MED RANGE GUIDANCE LATER THIS
WEEK...ALL OF WHICH INDICATES UPPER LOW SLOWLY LIFTING NORTH ALONG
THE CENTRAL APPALACHIANS. THIS SCENARIO SUPPORTS THE CHC OF
DIURNALLY ENHANCED SHRA/TSRA WED-THU AND POSSIBLY EVEN FRIDAY. NEARLY
ALL MDL DATA TRACKS TS ALBERTO WELL EAST OFF THE MID ATLANTIC
COAST TUE NIGHT WITH NO DIRECT IMPACT ON PA.

TEMPS THIS WEEK LOOK TO BE ABOVE NORMAL...MAINLY DUE TO WARM
OVERNIGHT LOWS. DEEP SOUTHERLY FLOW AHEAD OF UPPER LOW WILL
TRANSPORT ABOVE NORMAL MOISTURE NORTH ALONG THE E COAST...RESULTING
IN THE WARM NIGHTS.

EVEN WARMER WX APPEARS VERY LIKELY BY NEXT WEEKEND WHEN ALL MDL
DATA INDICATES A BUILDING UPPER LVL RIDGE OVER THE OHIO VALLEY.
HOWEVER...PA MAY BE ON PERIPHERY OF THIS FEATURE...PLACING AT
LEAST NORTHERN PA IN RING OF FIRE WITH CHC OF PM CONVECTION.

&&

.AVIATION /09Z MONDAY THROUGH FRIDAY/...
HIGH PRESSURE NOW MOVING OFF TO THE NORTHEAST. AN INCREASING MOIST
EAST TO SOUTHEAST FLOW HAS ALREADY BEGUN TO PUSH ATLANTIC MOISTURE
INTO CENTRAL PA...RESULTING IN MVFR CIGS ALREADY WORKING INTO THE
LOWER SUSQ. THESE LOWER CLOUDS WILL CONTINUE TO GRADUALLY SPREAD
NW THROUGH THE MORNING HOURS...EVENTUALLY ENCOMPASSING ALL TAF
SITES EXCEPT KBFD...AND LOWERING CIGS IN THE LOWER SUSQ /KMDT-
KLNS/ TO IFR. SHOWERS WILL ALSO INCREASE FROM THE SE DURING THE
DAY TODAY.

CIGS MAY RECOVER TO MVFR THIS AFTERNOON...WITH A TSTM EMBEDDED IN
THE NUMEROUS SHOWERS. BUT CIGS DROP AGAIN AND WILL BECOME IFR
AREAWIDE OVERNIGHT AS AS AN UPPER LEVEL TROF APPROACHES FROM THE
GREAT LAKES.

OUTLOOK...
MON NIGHT-WED...WIDESPREAD MVFR/IFR CIGS AND VSBYS LIKELY IN
SHOWERS AND SCT TSRA.
THU...PRIMARILY VFR. SCT SHRA/TSTM POSS MAINLY SE.
FRI...PRIMARILY VFR. ISOLD SHRA/TSTM POSS MAINLY SE.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...FITZGERALD
NEAR TERM...FITZGERALD
SHORT TERM...FITZGERALD
LONG TERM...FITZGERALD
AVIATION...JUNG/RXR

000
FXUS61 KPHI 210901
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
501 AM EDT MON MAY 21 2012

.SYNOPSIS...
LOW PRESSURE ALONG THE EAST COAST WILL PERSIST THROUGH WEDNESDAY.
THEREAFTER...CENTRAL ATLANTIC HIGH PRESSURE WILL CONTINUE A
SOUTHERLY FLOW OF RELATIVELY HUMID AIR UP THE EAST COAST THURSDAY
INTO AT LEAST THE START OF THE MEMORIAL DAY WEEKEND. THE PASSAGE OF
ANY COOL FRONT HERE ON SUNDAY OR MONDAY IS HIGHLY UNCERTAIN AND IF
IT DOESN`T OCCUR...HOT WEATHER WILL ARRIVE FROM OHIO VALLEY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE LARGE HIGH PRESSURE SYSTEM OFF THE CANADIAN WATERS AND LOW
PRESSURE OFF THE SOUTHEAST U.S. COAST WILL CONTINUE THE ONSHORE FLOW
OVER THE AREA TODAY. WEAK DISTURBANCES EMBEDDED IN THE FLOW WILL
PROVIDE OPPORTUNITIES FOR SHOWERS ACROSS THE AREA TODAY. ONE SUCH
DISTURBANCE WILL ROTATE ACROSS SRN NJ AND INTO SE PA BETWEEN 3 AM
AND 6 AM AND BRING OCNL SHOWERS/ISOLATED TSTMS AND A FEW DOWNPOURS.
THE TIMING OF OTHER DISTURBANCES TODAY IS DIFFICULT...BUT THE
WEATHER IS NOT EXPECTED TO MAKE ANY GREAT IMPROVEMENTS TODAY...SO WE
WILL KEEP RATHER HIGH POPS WITH OCNL SHOWERS. CHC FOR THUNDER SEEM
LOWER LATER TODAY. QPF .25 TO .50 BUT LOCALLY 1.00 TODAY.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM TUESDAY/...
NOT MUCH CHANGE TONIGHT. ONE SFC LOW WILL MOVE UP ALONG THE WATERS
TONIGHT...OTHER SHORTWAVES ALOFT WILL TRAVERSE THE AREA. POPS ARE
REDUCED BACK TO LOW LIKELY OR HIGH CHC POPS FOR TONIGHT. QPF AROUND
.10 TO .25 ACROSS THE AREA. WINDS BACK AROUND FROM ERLY TO NRLY AS
THE LOW MOVES NORTHWARD WELL EAST OF THE WATERS.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
TEMPERATURES: AVERAGE A BIT ABOVE NORMAL MOST OF THIS WORKWEEK
"POSSIBLY" TRENDING SUBSTANTIALLY ABOVE NORMAL THIS ENTIRE MEMORIAL
DAY WEEKEND...WITH THE CAVEAT THAT A BACKDOOR COLD FRONT MOVING
DOWN THROUGH NEW ENGLAND DOES NOT COME IN THE SIDE DOOR DOWN
HERE...IN OTHER WORDS...SLIDING SOUTHWEST THROUGH NEW JERSEY AND
DELAWARE.

THE HUMID CONDITIONS AND CONSIDERABLE CLOUDINESS MOST OF THIS WEEK
WILL FORCE NIGHTTIMES TO BE NOTABLY ABOVE NORMAL /5 TO 10 DEGREES
ON A DAILY BASIS/ WITH OUR DAYTIME MAXIMUM TEMPS CLOSER TO NORMAL.

WE ARE AWARE THE ECMWF IS CONSIDERABLY COOLER ON OUR DAYTIME MAX
TEMPS MUCH OF THIS WORKWEEK AND THEN WELL ABOVE OUR FORECAST FOR
NEXT SUNDAY AND MONDAY.

CLOUD COVER AND TIMING OF THE SHOWERY WEATHER CREATES THE UNCERTAINTY
OF FORECASTING MAX TEMPS THIS WORKWEEK AND THEN THE UNCERTAIN PASSAGE
OF ANY COLD FRONT HERE NEXT WEEKEND LIMITS EXPRESSION OF CONFIDENCE
REGARDING A POTENTIAL HEAT WAVE STARTING HERE SOMETIME DURING THE
MEMORIAL DAY WEEKEND.

500 MB: TROUGHING ALOFT IN THE EASTERN UNITED STATES PRODUCES A
PERSISTENTLY MORE HUMID AND INTERMITTENTLY SHOWERY REGIME HERE
THIS WEEK. THE TROUGH WILL BE REPLACED BY STRONG RIDGING...AND
DRYING ALOFT...RESULTING IN HEAT WAVE CONDITIONS OF 90 DEGREE HEAT
IN THE MIDWEST AND SOUTHERN UNITED STATES EVENTUALLY BUILDING
NORTHEASTWARD TOWARD OR INTO OUR AREA DURING THE MEMORIAL DAY
WEEKEND.


THE DAILIES...

TUESDAY THROUGH FRIDAY...WEAK FORCING AND OCCASIONAL INSTABILITY
WILL PRODUCE BANDS OF SHOWERS. SINCE THE STEERING WINDS ALOFT WILL
BE VERY LIGHT...THE BANDS OF CONVECTION WILL BE SLOW MOVING...
PERMITTING BANDS OR POCKETS OF HEAVY RAINFALL.  DAILY DETAILS CANNOT
BE RELIABLY OFFERED SO A BLEND OF 00Z/21 NCEP MOS GUIDANCE WAS USED
TO DEVELOP THE FCST ELEMENTS. WE NOTE THE ECMWF IS COOLER THAN OUR
330 AM DETERMINISTIC FCST THIS WEEK...BUT I THINK THIS IS LARGELY
PREDICATED ON THEIR CONSTANCY OF SHOWERY WEATHER. USUALLY IN THESE
PATTERNS THERE ARE LARGE CHUNKS OF TIME WHEN ITS NOT RAINING.
CONFIDENCE IMAGERY FOCUSED ON GFS 2M TEMPS FROM FSU EXPRESSES
ABOVE AVERAGE CONFIDENCE IN THE GFS 2M TEMP FCST THIS WEEK...IN
OTHER WORDS LEANING WARMER WHEN COMPARING THE 00Z/21 GFS TO THE
00Z/21 ECMWF IS THE WAY TO THINK ATTM.

MEMORIAL DAY WEEKEND...ON THE OTHER HAND...A DRYING OUT DOWN TO
800 MB AND HEATING UP IS FORECAST THIS 3 DAY PERIOD AND HERE THE
GFS 2M TEMP FCST IS EXPRESSING LESS THAN AVERAGE CONFIDENCE FOR
THIS 00Z/21 CYCLE. THAT SUGGESTS TO ME THAT THE ECMWF AND UKMET
ARE ON THE RIGHT TRACK SENDING 90 DEGREE HEAT INTO THE MID
ATLANTIC STATES BY SUNDAY OR MONDAY. THERE IS MODEL SPREAD ON THE
SOLUTION WHICH MEANS WE CANT BE SURE HOW WARM IT BECOME. THERE
STILL MAY BE CONSIDERABLE MOISTURE BELOW 800MB WHICH COULD LIMIT
REALIZING THE POTENTIAL THAT 850 MB TEMPS WILL BE OFFERING.

IN ANY CASE...THE SHOWERY WEATHER OF THIS WORK WEEK SHOULD BE
ALMOST NON EXISTENT THIS WEEKEND DUE TO SUBSIDENCE ASSOCIATED
WITH THE VERY STRONG RIDGE DEVELOPING ALOFT.

&&

.AVIATION /09Z MONDAY THROUGH FRIDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.

THE ONSHORE FLOW AND THE NOW SCT-OCNL SHOWERS ACROSS THE AREA HAS
HAD ITS EFFECT ON THE CIGS WITH IFR AT ALL AREAS EXCEPT KRDG AND
KABE. THESE LAST TWO SITES SHOULD BECOME IFR BEFORE DAWN. THE FCST
FOR CIGS/VSBYS TODAY AND TONIGHT IS RATHER LOW CONFID...WITH
CONDITIONS LIKELY REMAINING MOSTLY IFR THIS MORNING WITH POSSIBLY
SOME IMPROVEMENT BACK TO MVFR THIS AFTERNOON. CIGS/VSBYS MAY DROP
BACK TO IFR TONIGHT...AGAIN LOW CONFID IN PLACEMENT AND TIMING.
WINDS WILL REMAIN MOSTLY NERLY OR ERLY TODAY AND TONIGHT.

OUTLOOK...
TUESDAY THROUGH FRIDAY...MVFR OR IFR CONDS LATER EACH NIGHT AND
EARLY EACH DAY IN ST/FOG BECOMES VFR CIGS MIDDAY INTO THE EVENING.
LOCAL MVFR OR IFR CONDS IN SCATTERED SHOWERS OR EVEN A TSTM. LIGHT
WIND...TENDING TO BE MOSTLY SOUTHEAST TO SOUTH.

&&

.MARINE...
ONGOING SCA CONDITIONS WILL CONTINUE ON THE OCEAN FOR SEVERAL
PERIODS (BEYOND THE SHORT TERM) WHILE EITHER LOW END SCA OR
MARGINALLY CLOSE TO SCA CONDITIONS FOR THE LOWER DEL BAY OVER THE
NEXT FEW DAYS. CHOSE TO EXTEND THE PREVIOUS SCA FLAG FOR THE LOWER
BAY UNTIL 16Z...IT MAY BE EXTENDED BEYOND THAT CLOSE TO EXPIRATION
TIME...UNLESS THE WINDS SHOW SOME DOWNWARD TREND THAT LOOKS TO HOLD.
SCA WINDS AND SEAS WILL NOT EXTEND INTO NRN DEL BAY. SHOWERY
CONDITIONS WITH A FEW TSTMS THIS MORNING...MOSTLY OVER THE SRN
COASTAL WATERS.


OUTLOOK...
TUESDAY THROUGH FRIDAY.

WIND SPEEDS ARE FORECAST TO REMAIN BELOW THE SMALL CRAFT ADVISORY
CRITERION.

WAVE HEIGHTS ON OUR OCEAN WATERS MAY BE FLIRTING WITH HAZARDOUS
SEAS CRITERIA AT TIMES...ESPECIALLY TUESDAY...BUT FOR NOW...OTHER
THAN A 3 TO 4 FT SE SWELL OF 8 SECONDS...MUCH OF THIS TIME SHOULD
BE SCA FREE.

&&

.HYDROLOGY...
OCCASIONAL INSTABILITY IN ASSOCIATION WITH PERSISTENTLY HIGH HUMIDITY
AND COOL TROUGHING ALOFT WILL PROBABLY YIELD A COUPLE OF SWATHS OF
STORM TOTALS EXCEEDING 3 INCHES THIS WEEK. MOST OF THE AREA SHOULD
BE DOUSED BY AT LEAST HALF AN INCH THIS WEEK...INCLUDING AMOUNTS
THAT BEGAN THIS PAST SUNDAY EVENING. IF THERE WERE TO BE ANY SMALL
STREAM FLOOD PROBLEMS...IT WOULD MORE LIKELY OCCUR IN EASTERN
PENNSYLVANIA OR NORTHEAST NEW JERSEY WHERE GRIDDED FLASH FLOOD
GUIDANCE SHOWS GREATER VULNERABILITY. 1 HR FFG NEAR 1.3 INCHES AND
6 TO 24 HR GUIDANCE IS CURRENTLY NEAR 1.9 INCHES. THAT WOULD PLACE
MONTGOMERY...WITH THE NEARBY CHESTER COUNTY PA BORDER AND CENTRAL
MORRIS COUNTY NJ AS SEEMINGLY MOST VULNERABLE.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT TUESDAY FOR ANZ452>455.
     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 AM EDT TUESDAY
     FOR ANZ450-451.
     SMALL CRAFT ADVISORY UNTIL NOON EDT TODAY FOR ANZ431.

&&

$$

SYNOPSIS...DRAG
NEAR TERM...O`HARA
SHORT TERM...O`HARA
LONG TERM...DRAG 458A
AVIATION...DRAG/O`HARA 458A
MARINE...DRAG/O`HARA 458A
HYDROLOGY...
TIDES/COASTAL FLOODING...

000
FXUS61 KPHI 210759
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
359 AM EDT MON MAY 21 2012

.SYNOPSIS...
LOW PRESSURE ALONG THE EAST COAST WILL PERSIST THROUGH WEDNESDAY.
THEREAFTER...CENTRAL ATLANTIC HIGH PRESSURE WILL CONTINUE A
SOUTHERLY FLOW OF RELATIVELY HUMID AIR UP THE EAST COAST THURSDAY
INTO AT LEAST THE START OF THE MEMORIAL DAY WEEKEND. THE PASSAGE OF
ANY COOL FRONT HERE ON SUNDAY OR MONDAY IS HIGHLY UNCERTAIN AND IF
IT DOESN`T OCCUR...HOT WEATHER WILL ARRIVE FROM OHIO VALLEY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE LARGE HIGH PRESSURE SYSTEM OFF THE CANADIAN WATERS AND LOW
PRESSURE OFF THE SOUTHEAST U.S. COAST WILL CONTINUE THE ONSHORE FLOW
OVER THE AREA TODAY. WEAK DISTURBANCES EMBEDDED IN THE FLOW WILL
PROVIDE OPPORTUNITIES FOR SHOWERS ACROSS THE AREA TODAY. ONE SUCH
DISTURBANCE WILL ROTATE ACROSS SRN NJ AND INTO SE PA BETWEEN 3 AM
AND 6 AM AND BRING OCNL SHOWERS/ISOLATED TSTMS AND A FEW DOWNPOURS.
THE TIMING OF OTHER DISTURBANCES TODAY IS DIFFICULT...BUT THE
WEATHER IS NOT EXPECTED TO MAKE ANY GREAT IMPROVEMENTS TODAY...SO WE
WILL KEEP RATHER HIGH POPS WITH OCNL SHOWERS. CHC FOR THUNDER SEEM
LOWER LATER TODAY. QPF .25 TO .50 BUT LOCALLY 1.00 TODAY.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM TUESDAY/...
NOT MUCH CHANGE TONIGHT. ONE SFC LOW WILL MOVE UP ALONG THE WATERS
TONIGHT...OTHER SHORTWAVES ALOFT WILL TRAVERSE THE AREA. POPS ARE
REDUCED BACK TO LOW LIKELY OR HIGH CHC POPS FOR TONIGHT. QPF AROUND
.10 TO .25 ACROSS THE AREA. WINDS BACK AROUND FROM ERLY TO NRLY AS
THE LOW MOVES NORTHWARD WELL EAST OF THE WATERS.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
TEMPERATURES: AVERAGE A BIT ABOVE NORMAL MOST OF THIS WORKWEEK
"POSSIBLY" TRENDING SUBSTANTIALLY ABOVE THIS ENTIRE MEMORIAL DAY
WEEKEND...WITH THE CAVEAT THAT A BACKDOOR COLD FRONT MOVING DOWN
THROUGH NEW ENGLAND DOES NOT COME IN THE SIDE DOOR DOWN HERE...IN
OTHER WORDS...SLIDING SOUTHWEST THROUGH NEW JERSEY AND DELAWARE.

THE HUMID CONDITIONS AND CONSIDERABLE CLOUDINESS MOST OF THIS WEEK
WILL FORCE NIGHTTIMES TO BE NOTABLY ABOVE NORMAL /5 TO 10 DEGREES
ON A DAILY BASIS/ WITH OUR DAYTIME MAXIMUM TEMPS CLOSER TO NORMAL.

WE ARE AWARE THE ECMWF IS CONSIDERABLY COOLER ON OUR DAYTIME MAX
TEMPS MUCH OF THIS WORKWEEK AND THAN WELL ABOVE OUR FORECAST FOR
NEXT SUNDAY AND MONDAY.

CLOUD COVER AND TIMING OF THE SHOWERY WEATHER CREATES THE
UNCERTAINTY OF MAX TEMPS THIS WORKWEEK AND THEN THE UNCERTAIN
PASSAGE OF ANY COLD FRONT HERE NEXT WEEKEND LIMITS EXPRESSION OF
CONFIDENCE REGARDING A POTENTIAL HEAT WAVE STARTING HERE SOME
DURING THE MEMORIAL DAY WEEKEND.

500 MB: TROUGHING ALOFT IN THE EASTERN UNITED STATES PRODUCES A
PERSISTENTLY MORE HUMID AND INTERMITTENTLY SHOWERY REGIME HERE
THIS WEEK. THE TROUGH WILL BE REPLACED BY STRONG RIDGING...AND
DRYING ALOFT...RESULTING IN HEAT WAVE CONDITIONS OF 90 DEGREE HEAT
IN THE MIDWEST AND SOUTHERN UNITED STATES EVENTUALLY BUILDING
NORTHEASTWARD TOWARD OR INTO OUR AREA DURING THE MEMORIAL DAY
WEEKEND.


THE DAILIES...

TUESDAY THROUGH FRIDAY...WEAK FORCING AND OCCASIONAL INSTABILITY
WILL PRODUCE BANDS OF SHOWERS. SINCE THE STEERING WINDS ALOFT WILL
BE VERY LIGHT...THE BANDS OF CONVECTION WILL BE SLOW MOVING...
PERMITTING BANDS OR POCKETS OF HEAVY RAINFALL.  DAILY DETAILS CANNOT
BE RELIABLY OFFERED SO A BLEND OF 00Z/21 NCEP MOS GUIDANCE WAS USED
TO DEVELOP THE FCST ELEMENTS. WE NOTE THE ECMWF IS COOLER THAN OUR
330 AM DETERMINISTIC FCST THIS WEEK...BUT I THINK THIS IS LARGELY
PREDICATED ON THEIR CONSTANCY OF SHOWERY WEATHER. USUALLY IN THESE
PATTERNS THERE ARE LARGE CHUNKS OF RAINFREE WEATHER. CONFIDENCE
IMAGERY FOCUSED ON TEMPS FROM FSU EXPRESSES ABOVE AVERAGE
CONFIDENCE IN THE GFS 2M TEMP FCST THIS WEEK.

MEMORIAL DAY WEEKEND...ON THE OTHER HAND...A DRYING OUT AND
HEATING UP IS FORECAST THIS 3 DAY PERIOD AND HERE THE GFS 2M TEMP
FCST IS EXPRESSING LESS THAN AVERAGE CONFIDENCE FOR THIS 00Z/21
CYCLE. THAT SUGGESTS TO ME THAT THE ECMWF AND UKMET ARE ON THE
RIGHT TRACK SENDING 90 DEGREE HEAT INTO THE MID ATLANTIC STATES BY
SUNDAY OR MONDAY. THERE IS MODEL SPREAD ON THE SOLUTION. IN ANY
CASE...THE SHOWERY WEATHER OF THIS WORK WEEK SHOULD BE ALMOST NON
EXISTENT DUE TO SUBSIDENCE ASSOCIATED WITH THE VERY STRONG RIDGE
DEVELOPING ALOFT.


&&

.AVIATION /08Z MONDAY THROUGH FRIDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.

THE ONSHORE FLOW AND THE NOW SCT-OCNL SHOWERS ACROSS THE AREA HAS
HAD ITS EFFECT ON THE CIGS WITH IFR AT ALL AREAS EXCEPT KRDG AND
KABE. THESE LAST TWO SITES SHOULD BECOME IFR BEFORE DAWN. THE FCST
FOR CIGS/VSBYS TODAY AND TONIGHT IS RATHER LOW CONFID...WITH
CONDITIONS LIKELY REMAINING MOSTLY IFR THIS MORNING WITH POSSIBLY
SOME IMPROVEMENT BACK TO MVFR THIS AFTERNOON. CIGS/VSBYS MAY DROP
BACK TO IFR TONIGHT...AGAIN LOW CONFID IN PLACEMENT AND TIMING.
WINDS WILL REMAIN MOSTLY NERLY OR ERLY TODAY AND TONIGHT.

OUTLOOK...
TUESDAY THROUGH FRIDAY...MVFR OR IFR CONDS LATER EACH NIGHT AND
EARLY IN EACH DAY IN ST/FOG BECOMES VFR CIGS MIDDAY INTO THE
EVENING. LOCAL MVFR OR IFR CONDS IN SCATTERED SHOWERS OR EVEN A
TSTM. LIGHT WIND...TENDING TO BE MOSTLY SOUTHEAST TO SOUTH.

&&

.MARINE...
ONGOING SCA CONDITIONS WILL CONTINUE ON THE OCEAN FOR SEVERAL
PERIODS (BEYOND THE SHORT TERM) WHILE EITHER LOW END SCA OR
MARGINALLY CLOSE TO SCA CONDITIONS FOR THE LOWER DEL BAY OVER THE
NEXT FEW DAYS. CHOSE TO EXTEND THE PREVIOUS SCA FLAG FOR THE LOWER
BAY UNTIL 16Z...IT MAY BE EXTENDED BEYOND THAT CLOSE TO EXPIRATION
TIME...UNLESS THE WINDS SHOW SOME DOWNWARD TREND THAT LOOKS TO HOLD.
SCA WINDS AND SEAS WILL NOT EXTEND INTO NRN DEL BAY. SHOWERY
CONDITIONS WITH A FEW TSTMS THIS MORNING...MOSTLY OVER THE SRN
COASTAL WATERS.


OUTLOOK...
WIND SPEEDS ARE FORECAST TO REMAIN BELOW THE SMALL CRAFT ADVISORY
CRITERION FOR THE PERIOD TUESDAY THROUGH FRIDAY.

WAVE HEIGHTS ON OUR OCEAN WATERS MAY BE FLIRTING WITH HAZARDOUS
SEAS CRITERIA AT TIMES BUT FOR NOW...OTHER THAN A 3 TO 4 FT SE
SWELL OF 8 SECONDS MUCH OF THIS TIME SHOULD BE SCA FREE.


&&

.HYDROLOGY...
OCCASIONAL INSTABILITY IN ASSOCIATION WITH PERSISTENTLY HIGH HUMIDITY
AND COOL TROUGHING ALOFT WILL PROBABLY YIELD A COUPLE OF SWATHS OF
STORM TOTALS EXCEEDING 3 INCHES THIS WEEK. MOST OF THE AREA SHOULD
BE DOUSED BY AT LEAST HALF AN INCH THIS WEEK...INCLUDING AMOUNTS
THAT BEGAN THIS PAST SUNDAY EVENING. IF THERE WERE TO BE ANY SMALL
STREAM FLOOD PROBLEMS...IT WOULD MORE LIKELY OCCUR IN EASTERN
PENNSYLVANIA OR NORTHEAST NEW JERSEY WHERE GRIDDED FLASH FLOOD
GUIDANCE SHOWS GREATER VULNERABILITY. 1 HR FFG NEAR 1.3 INCHES AND
6 TO 24 HR GUIDANCE IS CURRENTLY NEAR 1.9 INCHES. THAT WOULD PLACE
MONTGOMERY...WITH THE NEARBY CHESTER COUNTY PA BORDER AND CENTRAL
MORRIS COUNTY NJ AS SEEMINGLY MOST VULNERABLE.

&&

.TIDES/COASTAL FLOODING...
WE`RE DROPPING THIS SECTION AFTER THIS ISSUANCE. NO TIDAL INUNDATION
FLOODING IS EXPECTED THIS WEEK.

&&

.RIP CURRENTS...
WHILE THE ONSHORE FLOW WILL PERSIST TODAY, IT IS FORECAST TO NOT
BE AS STRONG AS YESTERDAY. SEAS ARE LESS THAN YESTERDAY BY 2 FEET
BUT THE SE SWELL IS STILL NEAR 5 FEET WITH AN 8 SECOND PERIOD. BASED
ON THIS, WE PROBABLY WILL HAVE A MODERATE RISK OF RIP CURRENTS
TODAY.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT TUESDAY FOR ANZ452>455.
     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 AM EDT TUESDAY
     FOR ANZ450-451.
     SMALL CRAFT ADVISORY UNTIL NOON EDT TODAY FOR ANZ431.

&&

$$
SYNOPSIS...DRAG 359
NEAR TERM...O`HARA 359
SHORT TERM...O`HARA 359
LONG TERM...DRAG 359
AVIATION...DRAG/O`HARA 359
MARINE...DRAG/O`HARA 359
HYDROLOGY... 359
TIDES/COASTAL FLOODING... 359
RIP CURRENTS... 359

000
FXUS61 KPBZ 210742
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
342 AM EDT MON MAY 21 2012

.SYNOPSIS...
AS A COLD FRONT APPROACHES FROM THE WEST LOW PRESSURE WILL MOVE
ALONG THE EAST COAST THROUGH WEDNESDAY PRODUCING SCATTERED
SHOWERS AND THUNDERSTORMS. MILD TEMPERATURES WITH AN INCREASE IN
HUMIDITY THROUGH MID WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
RIDGE AXIS WILL WEAKEN ACROSS REGION TODAY AND WITH LOW PRESSURE
OVER VIRGINIA SLOWLY MOVING NORTHWEST, DEEPER MOISTURE WILL SPREAD
ACROSS THE RIDGES. A COLD FRONT NEAR THE INDIANA AND OHIO BORDER
WILL EDGE EAST AS WELL. THIS WILL BRING CHANCE POPS MAINLY THIS
AFTERNOON WITH HIGHER POPS ACROSS EASTERN 2/3RDS OF REGION.
LOWERED MAX TEMPS CLOSER TO NEW MAV GUIDANCE WHICH SEEMS
REASONABLE.

&&

.SHORT TERM /TUESDAY THROUGH THURSDAY/...
COLD FRONT WILL CONTINUE TO PROGRESS EAST MONDAY NIGHT AND MODELS IN
A BIT OF DISARRAY ON PLACEMENT OF UPPER TROUGH AS SURFACE LOW MOVES
OFF THE NEW ENGLAND COAST THROUGH PERIOD. NEW ECMWF SLOWER TO EXIT
UPPER TROUGH TO THE EAST AND HOLDS DEEPER MOISTURE BACK ACROSS UPPER
OHIO VALLEY INTO THURSDAY. PREVIOUS FORECAST HAS THIS WELL HANDLED
WITH HIGHEST POPS TUESDAY WITH FRONT. CHANCE POPS WEDNESDAY INTO
THURSDAY MAINLY ALONG THE RIDGES BUT SLIGHT CHANCE POPS ACROSS
MUCH OF THE REGION AS LOW LEVEL MOISTURE WILL REMAIN. IF ECMWF
SOLUTION IS MORE CORRECT MAY NEED HIGHER POPS WEDNESDAY AND
THURSDAY. TEMPERATURES WILL AVERAGE ABOVE NORMAL ESPECIALLY
OVERNIGHT. DEW POINTS HOVERING IN THE UPPER 50S TO NEAR 60 WILL
MAKE FOR MORE HUMID CONDITIONS.

&&

.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
00Z MODEL RUNS BRING RISING HEIGHTS ACROSS REGION BUT DIFFER ON
PLACEMENT AND INTENSITY OF DEVELOPING UPPER RIDGE. WILL KEEP
PREVIOUS TREND FOR ONLY ISOLATED POPS WITH ABOVE AVERAGE
TEMPERATURES APPROACHING 90 DEGREES AND SFC DEW POINTS IN THE LOW
TO MID 60S FOR THE START OF THE MEMORIAL DAY WEEKEND.

&&

.AVIATION /08Z MONDAY THROUGH FRIDAY/...
LOW PRESSURE WILL PULL ATLANTIC MOISTURE INTO THE AREA FROM THE
SOUTHEAST AND A FRONTAL BOUNDARY WILL APPROACH FROM THE WEST
LATER TODAY. THIS WILL MAKE ISOLATED SHOWERS AND THUNDERSTORMS WITH
MVFR RESTRICTIONS POSSIBLE ACROSS THE TERMINALS LATE THIS AFTERNOON
AND EVENING. WITH ISOLATED COVERAGE...THUNDERSTORMS ARE NOT
MENTIONED IN THE TAFS AT THIS POINT.

.OUTLOOK...MONDAY NIGHT THROUGH FRIDAY...
MOISTURE WILL INCREASE FROM THE EAST AS LOW PRESSURE MOVES UP THE
EASTERN SEABOARD. AN INCREASE IN LOW LEVEL MOISTURE MAY SET OFF
ISOLATED SHOWERS AND THUNDERSTORMS WITH RESTRICTIONS TONIGHT
THROUGH WEDNESDAY. SURFACE DEW POINTS WILL INCREASE THROUGH THE
PERIOD AND WILL LIKELY RESULT IN MVFR VISIBILITY RESTRICTIONS AT
MOST AIRPORT LOCATIONS DURING THE EARLY MORNING HOURS TUESDAY
THROUGH THURSDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$

000
FXUS61 KCTP 210621
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
221 AM EDT MON MAY 21 2012

.SYNOPSIS...
HIGH PRESSURE WILL PUSH WELL OFF THE COASTAL NEW ENGLAND WATERS
TONIGHT. AN INCREASING MOIST EAST TO SOUTHEAST FLOW WILL PUSH
ATLANTIC MOISTURE INTO CENTRAL PENNSYLVANIA EARLY MONDAY MORNING...AS
AN UPPER LEVEL TROF MOVES TO THE CENTRAL GREAT LAKES ON MONDAY.
THIS WILL BRING AN INCREASING CHANCE OF SHOWERS TO ALL OF CENTRAL
PA ON MONDAY. AN UPPER LEVEL LOW OVER THE SOUTHEAST WILL SLOWLY
TRACK NORTHEASTWARD THROUGH MID WEEK...KEEPING UNSETTLED WEATHER
ALONG THE EASTERN SEABOARD...AND A DAILY CHANCE OF SHOWERS AND
THUNDERSTORMS OVER CENTRAL PENNSYLVANIA. PENNSYLVANIA WILL BE ON
THE EDGE OF A BUILDING A LARGE UPPER HIGH ACROSS THE TENNESSEE
RIVER VALLEY AND SOUTHEASTERN STATES BY THE END OF THIS WEEK.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
STRATUS AND SCT SHRA OVERSPREADING SOUTHEAST PA EARLY THIS
MORNING...AS UPPER LOW AND ATTENDANT MOIST...EASTERLY LL JET
LIFTS UP THE E COAST. LATEST RUC AND 4KM NAM SUGGEST NORTHERN EDGE
OF SHOWERS/DRIZZLE WILL REACH FROM ARND BEDFORD TO SELINSGROVE BY
DAWN. INCREASING DWPTS AND CLOUD COVER WILL RESULT IN A MUCH
MILDER NIGHT THAN WE/VE SEEN RECENTLY WITH MIN TEMPS RANGING FROM
THE M50S ACROSS THE ALLEGHENY MTNS...TO THE L60S ACROSS THE LOWER
SUSQ VALLEY.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM TUESDAY/...
NO CHANGES TO THE THINKING ON MONDAY AS UPPER LOW OVER THE
SOUTHEAST CONUS WILL LIFT NORTH ALONG THE E COAST. ASSOCIATED
MOIST...EASTERLY LL JET AND UPPER LVL DIVERGENCE PRECEDING THE
UPPER LOW WILL LIKELY BRING SCT SHOWERS TO CENTRAL PA BEGINNING
LATE TONIGHT ACROSS THE SOUTHEAST ZONES AND OVERSPREADING THE
REST OF CENTRAL PA DURING MONDAY. CLOUD COVER...PRECIP AND
EASTERLY FLOW OFF THE ATLANTIC WILL RESULT IN A MUCH COOLER
MONDAY WITH MAX TEMPS ONLY ARND 70F. GEFS DATA SHOWING HIGHEST
PWATS ACROSS SOUTHEAST PA...WHERE THE BEST CHC OF MEASURABLE
RAINFALL IS EXPECTED SUN NITE/MONDAY.

DOWNSLOPING SE FLOW WILL RESULT IN PARTIAL SUNSHINE AND A
SOMEWHAT WARMER MONDAY OVR WARREN COUNTY...WHERE A LATE DAY
TSRA IS POSSIBLE. CAPE VALUES IN THE 600 TO 800JK-1 RANGE
ACROSS WARREN CO MON EVENING. FURTHER EAST...A COOLER MORE
STABLE EASTERLY FLOW SHOULD PRECLUDE THUNDER.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
NOT A LOT OF CHANGE FROM THE FCST PACKAGE YESTERDAY.

STILL LOOKS LIKE NORTHERN SYSTEM OFF THE COAST WILL PIVOT AROUND
ALBERTO AND MOVE WESTWARD...BRINGING SHOWERS TO THE AREA ON TUE.
MAIN CHC WILL BE MONDAY INTO TUE.

DID UP TEMPS SOME ON TUE...ALSO SOME CHC OF A THUNDERSTORM WITH
THE WARMER TEMPS.

SHOWERS COULD LINGER INTO WED...ESPECIALLY ACROSS THE SE WITH
THE FRONT.

TRIED TO GO WITH THE MID SHIFT FCST AND HAVE SOME PERIODS OF
DRY WEATHER. HARD TO FIND A LOT OF DRY PERIODS...AS REMAINS OF
CUTOFF COULD KEEP A FEW SHOWERS ACROSS EASTERN AREAS...WHERE
FAR NW AREAS COULD SEE SOME FROM THE COLD FRONT LATE IN THE
WEEK.

WENT WITH A DRY FCST FOR SUNDAY...IT WILL BE CLOSE...HARD TO
SEE THE EAST...WEST COLD FRONT DROPPING TOO FAR SOUTH.

TEMPS WILL BE WARM THROUGHOUT THE PERIOD...ABOVE NORMAL.

&&

.AVIATION /06Z MONDAY THROUGH FRIDAY/...
HIGH PRESSURE NOW MOVING OFF TO THE NORTHEAST. AN INCREASING MOIST
EAST TO SOUTHEAST FLOW HAS ALREADY BEGUN TO PUSH ATLANTIC MOISTURE
INTO CENTRAL PA...RESULTING IN MVFR CIGS ALREADY WORKING INTO THE
LOWER SUSQ. THESE LOWER CLOUDS WILL CONTINUE TO GRADUALLY SPREAD
NW THROUGH THE MORNING HOURS...EVENTUALLY ENCOMPASSING ALL TAF
SITES EXCEPT KBFD...AND LOWERING CIGS IN THE LOWER SUSQ /KMDT-
KLNS/ TO IFR. SHOWERS WILL ALSO INCREASE FROM THE SE DURING THE
DAY TODAY.

CIGS MAY RECOVER TO MVFR THIS AFTERNOON...WITH A TSTM EMBEDDED IN
THE NUMEROUS SHOWERS. BUT CIGS DROP AGAIN AND WILL BECOME IFR
AREAWIDE OVERNIGHT AS AS AN UPPER LEVEL TROF APPROACHES FROM THE
GREAT LAKES.

OUTLOOK...
MON NIGHT-WED...WIDESPREAD MVFR/IFR CIGS AND VSBYS LIKELY IN
SHOWERS AND SCT TSRA.
THU...PRIMARILY VFR. SCT SHRA/TSTM POSS MAINLY SE.
FRI...PRIMARILY VFR. ISOLD SHRA/TSTM POSS MAINLY SE.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...GRUMM/FITZGERALD
NEAR TERM...FITZGERALD
SHORT TERM...DEVOIR
LONG TERM...MARTIN
AVIATION...JUNG/RXR

000
FXUS61 KPBZ 210545
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
145 AM EDT MON MAY 21 2012

.SYNOPSIS...
BY MONDAY AFTERNOON...THE REGION WILL BE SQUEEZED BY AREAS OF
PRECIPITATION FROM THE WEST AND EAST AS LOW PRESSURE MOVES UP THE
EAST COAST AND A COLD FRONT APPROACHES FROM THE GREAT LAKES. THE BEST
CHANCE FOR SHOWERS WILL BE ON TUESDAY.

&&

.NEAR TERM /THROUGH TODAY/...
HIGH PRESSURE RIDGE CURRENTLY OVER THE REGION WILL BE PUSHED OFF
TO THE NORTHEAST TOWARD DAYBREAK. WITH LOW PRESSURE OVER VIRGINIA
SLOWLY MOVING NORTHWEST, DEEPER MOISTURE WILL SPREAD ACROSS THE
RIDGES TODAY WHILE A COLD FRONT NEAR THE INDIAN AND OHIO BORDER
MOVES SLOWLY EAST. CHANCE POPS AS THE DAY PROGRESSES WITH HIGHER
POPS ACROSS EASTERN 2/3RDS OF REGION. LOWERED MAX TEMPS A COUPLE
DEGREES FRO PREVIOUS FORECAST AS CLOUDS WILL BE INCREASING A BIT
QUICKER.

&&

.SHORT TERM /TONIGHT THROUGH WEDNESDAY/...
COLD FRONT WILL CONTINUE TO PROGRESS EAST MONDAY NIGHT AND MODELS IN
A BIT OF DISARRAY ON PLACEMENT OF UPPER TROF AS SURFACE LOW MOVES
OFF THE NEW ENGLAND COAST THROUGH PERIOD. WITH UPPER TROUGH
HANGING BACK ACROSS REGION AND AVAILABLE LOW LEVEL MOISTURE CHANCE
POPS FOR THE MOST PART THROUGH THE PERIOD WITH A TIME OF LIKELY
POPS ACROSS THE RIDGES. ENOUGH INSTABILITY FOR AN AFTERNOON
THUNDERSTORM BUT NOTHING WIDESPREAD. WITH CLOUDS AND SHOWERS
TEMPERATURES FORECAST TO BE ONLY A BIT ABOVE NORMAL WITH MILD
OVERNIGHT LOWS.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
A NEARLY STATIONARY UPPER LEVEL LOW/TROUGH WILL BE NEAR THE
CAROLINAS. HOWEVER...MODEL SOLUTIONS DIFFER. AT THIS TIME ENSEMBLE
TREND IS STILL TO KEEP A DRIER FORECAST FOR THE COUNTY WARNING
AREA...SO WILL CONTINUE THE TREND. THE PERIOD IS PROJECTED TO BE
WARM WITH ABOVE AVERAGE TEMPERATURES APPROACHING 90 DEGREES AND
SFC DEWPOINTS IN THE LOW TO MID 60S FOR THE START OF THE MEMORIAL
DAY WEEKEND.

&&

.AVIATION /06Z MONDAY THROUGH FRIDAY/...
LOW PRESSURE WILL PULL ATLANTIC MOISTURE INTO THE AREA FROM THE
SOUTHEAST AND A FRONTAL BOUNDARY WILL APPROACH FROM THE WEST
LATER TODAY. THIS WILL MAKE ISOLATED SHOWERS AND THUNDERSTORMS WITH
MVFR RESTRICTIONS POSSIBLE ACROSS THE TERMINALS LATE THIS AFTERNOON
AND EVENING. WITH ISOLATED COVERAGE...THUNDERSTORMS ARE NOT
MENTIONED IN THE TAFS AT THIS POINT.

.OUTLOOK...MONDAY NIGHT THROUGH FRIDAY...
MOISTURE WILL INCREASE FROM THE EAST AS LOW PRESSURE MOVES UP THE
EASTERN SEABOARD. AN INCREASE IN LOW LEVEL MOISTURE MAY SET OFF
ISOLATED SHOWERS AND THUNDERSTORMS WITH RESTRICTIONS TONIGHT
THROUGH WEDNESDAY. SURFACE DEWPOINTS WILL INCREASE THROUGH THE
PERIOD AND WILL LIKELY RESULT IN MVFR VISIBILITY RESTRICTIONS AT
MOST AIRPORT LOCATIONS DURING THE EARLY MORNING HOURS TUESDAY
THROUGH THURSDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$

000
FXUS61 KCTP 210545
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
145 AM EDT MON MAY 21 2012

.SYNOPSIS...
HIGH PRESSURE WILL PUSH WELL OFF THE COASTAL NEW ENGLAND WATERS
TONIGHT. AN INCREASING MOIST EAST TO SOUTHEAST FLOW WILL PUSH
ATLANTIC MOISTURE INTO CENTRAL PENNSYLVANIA EARLY MONDAY MORNING...AS
AN UPPER LEVEL TROF MOVES TO THE CENTRAL GREAT LAKES ON MONDAY.
THIS WILL BRING AN INCREASING CHANCE OF SHOWERS TO ALL OF CENTRAL
PA ON MONDAY. AN UPPER LEVEL LOW OVER THE SOUTHEAST WILL SLOWLY
TRACK NORTHEASTWARD THROUGH MID WEEK...KEEPING UNSETTLED WEATHER
ALONG THE EASTERN SEABOARD...AND A DAILY CHANCE OF SHOWERS AND
THUNDERSTORMS OVER CENTRAL PENNSYLVANIA. PENNSYLVANIA WILL BE ON
THE EDGE OF A BUILDING A LARGE UPPER HIGH ACROSS THE TENNESSEE
RIVER VALLEY AND SOUTHEASTERN STATES BY THE END OF THIS WEEK.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
STRATUS AND SCT SHRA OVERSPREADING SOUTHEAST PA EARLY THIS
MORNING...AS UPPER LOW AND ATTENDANT MOIST...EASTERLY LL JET
LIFTS UP THE E COAST. LATEST RUC AND 4KM NAM SUGGEST NORTHERN EDGE
OF SHOWERS/DRIZZLE WILL REACH FROM ARND BEDFORD TO SELINSGROVE BY
DAWN. INCREASING DWPTS AND CLOUD COVER WILL RESULT IN A MUCH
MILDER NIGHT THAN WE/VE SEEN RECENTLY WITH MIN TEMPS RANGING FROM
THE M50S ACROSS THE ALLEGHENY MTNS...TO THE L60S ACROSS THE LOWER
SUSQ VALLEY.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM TUESDAY/...
NO CHANGES TO THE THINKING ON MONDAY AS UPPER LOW OVER THE
SOUTHEAST CONUS WILL LIFT NORTH ALONG THE E COAST. ASSOCIATED
MOIST...EASTERLY LL JET AND UPPER LVL DIVERGENCE PRECEDING THE
UPPER LOW WILL LIKELY BRING SCT SHOWERS TO CENTRAL PA BEGINNING
LATE TONIGHT ACROSS THE SOUTHEAST ZONES AND OVERSPREADING THE
REST OF CENTRAL PA DURING MONDAY. CLOUD COVER...PRECIP AND
EASTERLY FLOW OFF THE ATLANTIC WILL RESULT IN A MUCH COOLER
MONDAY WITH MAX TEMPS ONLY ARND 70F. GEFS DATA SHOWING HIGHEST
PWATS ACROSS SOUTHEAST PA...WHERE THE BEST CHC OF MEASURABLE
RAINFALL IS EXPECTED SUN NITE/MONDAY.

DOWNSLOPING SE FLOW WILL RESULT IN PARTIAL SUNSHINE AND A
SOMEWHAT WARMER MONDAY OVR WARREN COUNTY...WHERE A LATE DAY
TSRA IS POSSIBLE. CAPE VALUES IN THE 600 TO 800JK-1 RANGE
ACROSS WARREN CO MON EVENING. FURTHER EAST...A COOLER MORE
STABLE EASTERLY FLOW SHOULD PRECLUDE THUNDER.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
NOT A LOT OF CHANGE FROM THE FCST PACKAGE YESTERDAY.

STILL LOOKS LIKE NORTHERN SYSTEM OFF THE COAST WILL PIVOT AROUND
ALBERTO AND MOVE WESTWARD...BRINGING SHOWERS TO THE AREA ON TUE.
MAIN CHC WILL BE MONDAY INTO TUE.

DID UP TEMPS SOME ON TUE...ALSO SOME CHC OF A THUNDERSTORM WITH
THE WARMER TEMPS.

SHOWERS COULD LINGER INTO WED...ESPECIALLY ACROSS THE SE WITH
THE FRONT.

TRIED TO GO WITH THE MID SHIFT FCST AND HAVE SOME PERIODS OF
DRY WEATHER. HARD TO FIND A LOT OF DRY PERIODS...AS REMAINS OF
CUTOFF COULD KEEP A FEW SHOWERS ACROSS EASTERN AREAS...WHERE
FAR NW AREAS COULD SEE SOME FROM THE COLD FRONT LATE IN THE
WEEK.

WENT WITH A DRY FCST FOR SUNDAY...IT WILL BE CLOSE...HARD TO
SEE THE EAST...WEST COLD FRONT DROPPING TOO FAR SOUTH.

TEMPS WILL BE WARM THROUGHOUT THE PERIOD...ABOVE NORMAL.

&&

.AVIATION /06Z MONDAY THROUGH FRIDAY/...
VFR CONDITIONS PREVAIL ACROSS CENTRAL PENNSYLVANIA. MID CLOUDS
STARTING TO STREAM INTO SOUTHERN TIER COUNTIES AND MAKING THEIR
WAY INTO CENTRAL PA...WITH CIGS 050 TO 100.

EASTERLY FLOW WILL PERSIST OVERNIGHT...AND BRING WITH IT A GRADUAL
INCREASE CLOUDS SPREADING IN FROM THE SOUTHWEST. BY 06Z MVFR CIGS
EXPECTED OVER KMDT AND KLNS...AND BY MONDAY MORNING /12Z/ EXPECT
MVFR CIGS TO OVERSPREAD MUCH OF SOUTHEAST PENNSYLVANIA INTO THE
LAURELS. MOISTURE WILL CONTINUE TO INCREASE ACROSS THE REGION ON
SOUTHEAST LOW LEVEL FLOW...AS DEEP LOW LIFTS INTO THE REGION. MVFR
TO IFR CIGS EXPECTED TO OVERSPREAD MOST OF CENTRAL PENNSYLVANIA BY
14-16Z...WITH INCREASING SHOWERS. EXCEPTION MAY BE FAR NW /KBFD/
WHERE VFR CONDITIONS MAY LINGER INTO LATER AFTERNOON.

OUTLOOK...
MON NIGHT-WED...WIDESPREAD MVFR/IFR CIGS AND VSBYS LIKELY IN
SHOWERS AND SCT TSRA.
THU...PRIMARILY VFR. SCT SHRA/TSTM POSS MAINLY SE.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...GRUMM/FITZGERALD
NEAR TERM...FITZGERALD
SHORT TERM...DEVOIR
LONG TERM...MARTIN
AVIATION...JUNG/DEVOIR

000
FXUS61 KPBZ 210513
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
113 AM EDT MON MAY 21 2012

.SYNOPSIS...
BY MONDAY AFTERNOON...THE REGION WILL BE SQUEEZED BY AREAS OF
PRECIPITATION FROM THE WEST AND EAST AS LOW PRESSURE MOVES UP THE
EAST COAST AND A COLD FRONT APPROACHES FROM THE GREAT LAKES. THE BEST
CHANCE FOR SHOWERS WILL BE ON TUESDAY.

&&

.NEAR TERM /THROUGH TODAY/...
HIGH PRESSURE RIDGE CURRENTLY OVER THE REGION WILL BE PUSHED OFF
TO THE NORTHEAST TOWARD DAYBREAK. WITH LOW PRESSURE OVER VIRGINIA
SLOWLY MOVING NORTHWEST, DEEPER MOISTURE WILL SPREAD ACROSS THE
RIDGES TODAY WHILE A COLD FRONT NEAR THE INDIAN AND OHIO BORDER
MOVES SLOWLY EAST. CHANCE POPS AS THE DAY PROGRESSES WITH HIGHER
POPS ACROSS EASTERN 2/3RDS OF REGION. LOWERED MAX TEMPS A COUPLE
DEGREES FRO PREVIOUS FORECAST AS CLOUDS WILL BE INCREASING A BIT
QUICKER.

&&

.SHORT TERM /TONIGHT THROUGH WEDNESDAY/...
COLD FRONT WILL CONTINUE TO PROGRESS EAST MONDAY NIGHT AND MODELS IN
A BIT OF DISARRAY ON PLACEMENT OF UPPER TROF AS SURFACE LOW MOVES
OFF THE NEW ENGLAND COAST THROUGH PERIOD. WITH UPPER TROUGH
HANGING BACK ACROSS REGION AND AVAILABLE LOW LEVEL MOISTURE CHANCE
POPS FOR THE MOST PART THROUGH THE PERIOD WITH A TIME OF LIKELY
POPS ACROSS THE RIDGES. ENOUGH INSTABILITY FOR AN AFTERNOON
THUNDERSTORM BUT NOTHING WIDESPREAD. WITH CLOUDS AND SHOWERS
TEMPERATURES FORECAST TO BE ONLY A BIT ABOVE NORMAL WITH MILD
OVERNIGHT LOWS.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
A NEARLY STATIONARY UPPER LEVEL LOW/TROUGH WILL BE NEAR THE
CAROLINAS. HOWEVER...MODEL SOLUTIONS DIFFER. AT THIS TIME ENSEMBLE
TREND IS STILL TO KEEP A DRIER FORECAST FOR THE COUNTY WARNING
AREA...SO WILL CONTINUE THE TREND. THE PERIOD IS PROJECTED TO BE
WARM WITH ABOVE AVERAGE TEMPERATURES APPROACHING 90 DEGREES AND
SFC DEWPOINTS IN THE LOW TO MID 60S FOR THE START OF THE MEMORIAL
DAY WEEKEND.

&&

.AVIATION /06Z MONDAY THROUGH FRIDAY/...
VFR CONDITIONS WILL PREVAIL ACROSS THE TERMINALS THROUGH TOMORROW
MORNING AS HIGH PRESSURE SHIFTS NORTHEAST OF THE AREA.

LOW PRESSURE WILL PULL ATLANTIC MOISTURE INTO THE AREA FROM THE
SOUTHEAST AND A FRONTAL BOUNDARY WILL APPROACH FROM THE WEST
TOMORROW AFTERNOON. THIS WILL MAKE ISOLATED SHOWERS AND
THUNDERSTORMS WITH MVFR RESTRICTIONS POSSIBLE ACROSS THE TERMINALS
LATE TOMORROW AFTERNOON INTO THE EVENING. WITH ISOLATED COVERAGE,
-TSRA IS NOT MENTIONED IN THE TAFS AT THIS POINT. NEAR CALM WINDS
OVERNIGHT WILL BECOME SOUTHEASTERLY AT AROUND 5KTS TOMORROW.

.OUTLOOK...MONDAY NIGHT THROUGH FRIDAY...
MOISTURE WILL INCREASE FROM THE EAST AS LOW PRESSURE MOVES UP THE
EASTERN SEABOARD. AN INCREASE IN LOW LEVEL MOISTURE MAY SET OFF
ISOLATED SHOWERS AND THUNDERSTORMS WITH RESTRICTIONS MONDAY NIGHT
THROUGH WEDNESDAY. SFC DEWPOINTS WILL INCREASE THROUGH THE PERIOD
AND WILL RESULT IN VISIBILITY RESTRICTIONS DUE TO HZ/BR AT MOST
AIRPORT LOCATIONS DURING THE EARLY MORNING HOURS WEDNESDAY AND
THURSDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$

000
FXUS61 KPHI 210437
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1237 AM EDT MON MAY 21 2012

.SYNOPSIS...
AN AREA OF LOW PRESSURE WILL MOVE INTO THE MID ATLANTIC REGION FROM
THE EAST TONIGHT, THEN DISSIPATE MONDAY. DURING THE EARLY PART OF
THE WEEK, LOW PRESSURE SHOULD LIFT NORTHEASTWARD FROM THE BAHAMAS
FOLLOWED BY TROPICAL STORM ALBERTO. BOTH SYSTEMS ARE EXPECTED TO
REMAIN WELL TO OUR EAST. A SLOW MOVING FRONTAL BOUNDARY IS FORECAST
TO APPROACH FROM THE WEST TUESDAY AND IT WILL INFLUENCE OUR WEATHER
DURING THE MID WEEK PERIOD BEFORE DISSIPATING. HIGH PRESSURE IS
ANTICIPATED TO BUILD INTO OUR REGION FOR FRIDAY AND SATURDAY. A COLD
FRONT FROM THE NORTH MAY ARRIVE SUNDAY.

&&

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

AN AREA OF LOW PRESSURE WILL CONTINUE TO SLIDE WESTWARD AND MOVE
INTO VIRGINIA THROUGH TONIGHT. THE FLOW AROUND THIS LOW ALONG WITH
HIGH PRESSURE SITUATED TO OUR NORTHEAST WILL MAINTAIN AN ONSHORE
COMPONENT. THE OVERALL FLOW IS FORECAST TO WEAKEN SOME AS THE
GRADIENT SUBSIDES DUE TO THE LOW WEAKENING. HOWEVER, A PLUME OF
MOISTURE WILL ADVECT INTO THE AREA WITH THE MODEL GUIDANCE
INDICATING THE PW VALUES INCREASING TO NEAR 1.5 INCHES OVERNIGHT.
THERE APPEARS TO BE AN IMPULSE ROTATING AROUND THE SURFACE LOW AND
THIS LOOKS TO BE WHAT THE MAJORITY OF THE MODELS ARE KEYING IN ON.
THIS RESULTS IN SHOWERS THAT EXPAND FROM SOUTHEAST TO NORTHWEST
ACROSS A GOOD PART OF THE CWA DURING THE NIGHT. THIS AREA LOOKS TO
BE THE SHOWERS THAT ARE MOVING ACROSS SOUTHERN DELAWARE AS OF
0130Z. THE OVERALL TIMING ON THIS HAS SOME LOWER CONFIDENCE,
HOWEVER GIVEN THE INCREASING MOISTURE SOME LOCAL DOWNPOURS WILL BE
QUITE POSSIBLE ESPECIALLY OVERNIGHT. AS A RESULT, THE POPS
INCREASE FROM SOUTHEAST TO NORTHWEST DURING THE COURSE OF THE
NIGHT. BASED ON THE DEEPENING MOISTURE AND LOWERING CLOUD BASES,
SOME DRIZZLE CANNOT BE RULED OUT.

THERE IS NOT A LOT OF INSTABILITY FORECAST TO OCCUR, THEREFORE
JUST A SLIGHT CHC OF THUNDER /ISOLATED/ WAS CARRIED ACROSS
PORTIONS OF THE FAR SOUTHEASTERN CWA FOR AWHILE TONIGHT. MUCH OF
THE CONVECTION THAT IS WELL OFFSHORE WEAKENS AS IT MOVES TOWARD
THE COAST.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM TUESDAY/...
MDL SOLNS DIFFER A BIT ON PRECIP TOMORROW. WE WILL STILL BE
IMPACTED BY THE AFOREMENTIONED LOW, BUT IT WILL NOT BE A
COMPLETELY RAINY DAY BY ANY MEANS. THERE WILL BE SHOWERS
AS PIECES OF ENERGY ROTATE AROUND THE LOW. AS A RESULT, THE MDLS
ARE HAVING THEIR DIFFS DETERMINING WHICH PDS WILL BE WET AND WHICH
ONES WILL BE DRY. THERE ARE SOME INDICATIONS THAT THE MORNING
COULD BE WETTER THAN THE AFTN, OVERALL. QPF SHOULD BE 0.50 INCHES
OR LESS.

&&

.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
THE EFFECTS OF TROPICAL STORM ALBERTO SHOULD REMAIN TO OUR EAST
AND WILL LIKELY NOT INFLUENCE OUR LAND AREAS. NEVERTHELESS, THE
WEATHER IS GOING TO BE RATHER UNSETTLED FROM MONDAY NIGHT INTO
THURSDAY. THERE WILL BE A RELATIVELY LIGHT FLOW NEAR THE SURFACE
AS WELL AS IN THE MID AND UPPER LEVELS OF THE ATMOSPHERE DURING
MUCH OF THE PERIOD. A FAIR AMOUNT OF LOW LEVEL MOISTURE SHOULD
LINGER IN OUR REGION. AS A RESULT, CLOUDS AND SCATTERED SHOWERS
ARE ANTICIPATED.

A SLOW MOVING BOUNDARY FROM THE WEST SHOULD BEGIN TO APPROACH
FROM THE WEST ON TUESDAY BEFORE MOVING INTO OUR VICINITY FOR
TUESDAY NIGHT AND WEDNESDAY. THE FRONT IS EXPECTED TO DISSIPATE
GRADUALLY.

WITH DAYTIME HEATING, THERE WILL BE AN INCREASE IN INSTABILITY
DURING THE AFTERNOON AND EVENING HOURS ON TUESDAY AND WEDNESDAY,
ESPECIALLY AT LOCATIONS A BIT REMOVED FROM THE OCEAN INFLUENCE. AS
A RESULT, WE WILL INDICATE AT CHANCE OF AFTERNOON AND EVENING
THUNDERSTORMS ON BOTH DAYS, EXCEPT NEAR THE COAST.

WITH THE REMNANTS OF THE BOUNDARY IN OR NEAR OR REGION ON
THURSDAY AND WITH A MID LEVEL TROUGH OR LOW PASSING NEARBY OR
OVERHEAD, WE WILL AGAIN CARRY A CHANCE OF SHOWERS AND
THUNDERSTORMS.

DUE TO THE LIGHT ATMOSPHERIC FLOW, ANY SHOWERS AND THUNDERSTORMS
ON TUESDAY, WEDNESDAY AND THURSDAY MAY BE SLOW MOVING AND THEY
COULD LEAVE MODERATE TO HEAVY RAINFALL AT SOME LOCATIONS.

HIGH PRESSURE IS EXPECTED TO PUSH INTO OUR REGION FROM THE
NORTHEAST FOR FRIDAY AND SATURDAY WITH A TREND TOWARD DRY WEATHER
ANTICIPATED. A FRONTAL BOUNDARY FROM THE NORTHWEST MAY ARRIVE ON
SATURDAY NIGHT OR SUNDAY.

TEMPERATURES SHOULD BE NEAR OR SLIGHTLY ABOVE NORMAL FOR THIS
TIME OF THE YEAR FROM MONDAY NIGHT THROUGH THURSDAY NIGHT. WITH
DRY AIR BUILDING INTO OUR REGION, ABOVE NORMAL TEMPERATURES ARE
EXPECTED FOR FRIDAY INTO THE WEEKEND, EVEN WITH THE ARRIVAL OF THE
FRONTAL BOUNDARY FROM THE NORTHWEST.

&&

.AVIATION /06Z MONDAY THROUGH FRIDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.

THE AIRMASS WILL CONTINUE TO MOISTEN FROM EAST TO WEST TONIGHT,
THEREFORE THE LOWERING CLOUD BASES WILL MIGRATE INLAND. THE MAIN
FORECAST CHALLENGES ARE HOW QUICKLY THIS OCCURS AND HOW LOW THE
CEILINGS END UP GETTING. AS THE SURFACE TEMPERATURES CONTINUE TO
COOL, THE CLOUDS WILL LOWER FROM EAST TO WEST. THIS IS ALREADY
OCCURRING WITH IFR CEILINGS IN THE KACY AREAS WITH MVFR TO THE
KPHL METRO AREA. THESE LOWERING CEILINGS WILL CONTINUE WESTWARD
AND WE BOUGHT ALL OF OUR TERMINALS DOWN TO MVFR THEN EVEN TO IFR,
WITH KABE AND KRDG SEEING THE LATTER LAST.

THERE WILL BE SHOWERS DEVELOPING AS WELL GENERALLY FROM SOUTHEAST TO
NORTHWEST DURING THE COURSE OF THE NIGHT. THERE IS LOWER CONFIDENCE
ON THE TIMING AND COVERAGE OF THESE, HOWEVER GIVEN THE DEEPENING
MOISTURE THROUGH THE NIGHT, LOCAL DOWNPOURS WILL BE POSSIBLE. THE
MAIN SHOWERS LOOK TO BE WHAT IS MOVING ACROSS SOUTHERN DELAWARE
AND OFFSHORE OF SOUTHEASTERN NEW JERSEY AS OF 0130Z. THE THUNDER
CHANCES SEEM TO BE RATHER LOW, THEREFORE NO MENTION WAS INCLUDED
AT THIS TIME. THE NORTHEAST TO EAST WINDS WILL SETTLE THROUGH THE
NIGHT GENERALLY TO ABOUT 10 KNOTS, AS THE PRESSURE GRADIENT
WEAKENS SOME DUE TO THE LOW PRESSURE SYSTEM TO OUR SOUTH
WEAKENING. THE MOISTURE APPEARS TO BE DEEP ENOUGH ALREADY AND WITH
THE SURFACE DEW POINTS COMING UP SOME THAT SOME FOG HAS DEVELOPED
EARLY THIS EVENING FROM ABOUT KACY TO KWWD. WE HAVE LOWER
CONFIDENCE IF THIS SPREADS INLAND, THEREFORE WE RESTRICTED IT AT
KACY TO NEAR KMIV FOR AWHILE TONIGHT.

FOR MONDAY, SUB-VFR CONDITIONS ARE EXPECTED TO CONTINUE AS A
WEAKNESS IN THE ATMOSPHERE REMAINS IN PLACE ALONG WITH AN ABUNDANCE
OF MOISTURE. THERE SHOULD BE LOWER CLOUDS AND PERHAPS A TOUCH OF FOG
IN THE MORNING ALONG WITH SHOWERS, THE THERE MAY BE A LULL IN THE
SHOWERS FOR AWHILE. AGAIN, THERE IS LOWER CONFIDENCE REGARDING
THE TIMING AND COVERAGE OF THE SHOWERS. WHILE SOME THUNDERSTORMS ARE
POSSIBLE, THEY DO NOT APPEAR TO BE ALL THAT WIDESPREAD, THEREFORE
THIS WAS NOT INCLUDED AT THIS TIME. THE WINDS WILL GENERALLY BE FROM
THE EAST AROUND 10 KNOTS.

OUTLOOK...
MONDAY NIGHT THROUGH THURSDAY...MVFR/IFR CEILING AND VISIBILITY
VALUES ARE POSSIBLE, ALONG WITH SCATTERED SHOWERS, DURING THE
OVERNIGHT AND MORNING HOURS EACH DAY. MAINLY VFR CONDITIONS ARE
EXPECTED DURING THE AFTERNOON AND EVENING HOURS, EXCEPT IN
SCATTERED SHOWERS AND THUNDERSTORMS. THE WIND SHOULD BE MAINLY 10
KNOTS OR LESS AND IT MAY FAVOR THE EAST TO SOUTH QUADRANT.

THURSDAY NIGHT AND FRIDAY...MAINLY VFR WITH A SOUTH WIND 10 KNOTS
OR LESS. SOME LATE NIGHT AND EARLY MORNING VISIBILITY RESTRICTIONS
ARE POSSIBLE.

&&

.MARINE...
MARGINAL SCA CONDITIONS CONTINUE ON THE LOWER DEL BAY...THE SCA
FLAG HAS BEEN EXTENDED UNTIL 12Z.

PROLONGED NORTHEAST TO EAST FLOW IS EXPECTED THROUGH MONDAY AS LOW
PRESSURE WEAKENS ACROSS THE MID ATLANTIC. SEAS WILL REMAIN AT OR
ABOVE 5 FEET WITH THE HIGHER SETS ACROSS THE SOUTHERN WATERS DUE TO
A LONGER FETCH AND INITIALLY STRONGER WINDS. THE SMALL CRAFT ADVISORY
REMAINS IN EFFECT AS A RESULT THROUGH MONDAY. THE WINDS WILL GUST
THROUGH THIS EVENING, ESPECIALLY ACROSS THE SOUTHERN WATERS, THEN
TEND TO DIMINISH SOME LATER TONIGHT AS THE PRESSURE GRADIENT BEGINS
TO RELAX SOME.

OUTLOOK...
WIND SPEEDS ARE FORECAST TO REMAIN BELOW THE SMALL CRAFT ADVISORY
CRITERION FOR THE PERIOD FROM MONDAY NIGHT THROUGH FRIDAY.

WAVE HEIGHTS ON OUR OCEAN WATERS ARE EXPECTED TO REMAIN AT 5 FEET
OR GREATER INTO THE MID WEEK PERIOD, AS TROPICAL STORM ALBERTO
PASSES WELL TO OUR EAST. FOR NOW, THE SMALL CRAFT ADVISORY ON OUR
OCEAN WATERS HAS BEEN EXTENDED UNTIL 600 AM TUESDAY.

&&


.RIP CURRENTS...
WHILE THE ONSHORE FLOW WILL PERSIST MONDAY, IT IS FORECAST TO NOT
BE AS STRONG AS SUNDAY. IN ADDITION, THE SEAS ARE FORECAST TO BE
SOMEWHAT LOWER. BASED ON THIS, WE CAME UP WITH A MODERATE RISK OF
RIP CURRENTS FOR MONDAY.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT TUESDAY FOR ANZ452>455.
     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 AM EDT TUESDAY
     FOR ANZ450-451.
     SMALL CRAFT ADVISORY UNTIL 8 AM EDT THIS MORNING FOR ANZ431.

&&

$$
SYNOPSIS...GORSE/IOVINO
NEAR TERM...GORSE/OHARA
SHORT TERM...NIERENBERG
LONG TERM...IOVINO
AVIATION...GORSE/IOVINO
MARINE...GORSE/IOVINO/OHARA
RIP CURRENTS...

000
FXUS61 KCTP 210324
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1124 PM EDT SUN MAY 20 2012

.SYNOPSIS...
HIGH PRESSURE WILL PUSH WELL OFF THE COASTAL NEW ENGLAND WATERS
TONIGHT. AN INCREASING MOIST EAST TO SOUTHEAST FLOW WILL PUSH
ATLANTIC MOISTURE INTO CENTRAL PENNSYLVANIA EARLY MONDAY MORNING...AS
AN UPPER LEVEL TROF MOVES TO THE CENTRAL GREAT LAKES ON MONDAY.
THIS WILL BRING AN INCREASING CHANCE OF SHOWERS TO ALL OF CENTRAL
PA ON MONDAY. AN UPPER LEVEL LOW OVER THE SOUTHEAST WILL SLOWLY
TRACK NORTHEASTWARD THROUGH MID WEEK...KEEPING UNSETTLED WEATHER
ALONG THE EASTERN SEABOARD...AND A DAILY CHANCE OF SHOWERS AND
THUNDERSTORMS OVER CENTRAL PENNSYLVANIA. PENNSYLVANIA WILL BE ON
THE EDGE OF A BUILDING A LARGE UPPER HIGH ACROSS THE TENNESSEE
RIVER VALLEY AND SOUTHEASTERN STATES BY THE END OF THIS WEEK.

&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
CLEAR SKIES SHOULD PREVAIL FOR MOST OF CENTRAL PA THIS
EVENING...WITH LOW CLOUDS APPROACHING LATE THIS EVENING ACROSS
LANCASTER AND YORK COUNTIES. CLOUDS WILL CONTINUE THEIR TREK
WESTWARD AND NORTHWARD...EVENTUALLY OVERSPREADING MOST IF NOT ALL
OF CENTRAL PA BY 15Z MON. FAR NORTHWEST AREAS MAY ESCAPE BKN CIGS.
ALL BUT THE LOWER SUSQ. SHOULD REMAIN DRY TONIGHT...BUT AREAS OF
DRIZZLE AND LIGHT SHOWERS ARE CERTAINLY POSSIBLE IN THE DEEPER
MARITIME AIR MASS OVER THE LOWER SUSQ RIVER VALLEY BEFORE 12Z.
OVERNIGHT MINS WILL BE MUCH MILDER WITH THE INCREASING CLOUD
COVER...AND WILL RANGE FROM THE LOWER 50S IN THE NORTH TO THE MID
TO UPPER 50S SOUTHEAST.

&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/...
NO CHANGES TO THE THINKING ON MONDAY AS UPPER LOW OVER THE
SOUTHEAST CONUS WILL LIFT NORTH ALONG THE E COAST. ASSOCIATED
MOIST...EASTERLY LL JET AND UPPER LVL DIVERGENCE PRECEDING THE
UPPER LOW WILL LIKELY BRING SCT SHOWERS TO CENTRAL PA BEGINNING
LATE TONIGHT ACROSS THE SOUTHEAST ZONES AND OVERSPREADING THE
REST OF CENTRAL PA DURING MONDAY. CLOUD COVER...PRECIP AND
EASTERLY FLOW OFF THE ATLANTIC WILL RESULT IN A MUCH COOLER
MONDAY WITH MAX TEMPS ONLY ARND 70F. GEFS DATA SHOWING HIGHEST
PWATS ACROSS SOUTHEAST PA...WHERE THE BEST CHC OF MEASURABLE
RAINFALL IS EXPECTED SUN NITE/MONDAY.

DOWNSLOPING SE FLOW WILL RESULT IN PARTIAL SUNSHINE AND A
SOMEWHAT WARMER MONDAY OVR WARREN COUNTY...WHERE A LATE DAY
TSRA IS POSSIBLE. CAPE VALUES IN THE 600 TO 800JK-1 RANGE
ACROSS WARREN CO MON EVENING. FURTHER EAST...A COOLER MORE
STABLE EASTERLY FLOW SHOULD PRECLUDE THUNDER.

&&

.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
NOT A LOT OF CHANGE FROM THE FCST PACKAGE YESTERDAY.

STILL LOOKS LIKE NORTHERN SYSTEM OFF THE COAST WILL PIVOT AROUND
ALBERTO AND MOVE WESTWARD...BRINGING SHOWERS TO THE AREA ON TUE.
MAIN CHC WILL BE MONDAY INTO TUE.

DID UP TEMPS SOME ON TUE...ALSO SOME CHC OF A THUNDERSTORM WITH
THE WARMER TEMPS.

SHOWERS COULD LINGER INTO WED...ESPECIALLY ACROSS THE SE WITH
THE FRONT.

TRIED TO GO WITH THE MID SHIFT FCST AND HAVE SOME PERIODS OF
DRY WEATHER. HARD TO FIND A LOT OF DRY PERIODS...AS REMAINS OF
CUTOFF COULD KEEP A FEW SHOWERS ACROSS EASTERN AREAS...WHERE
FAR NW AREAS COULD SEE SOME FROM THE COLD FRONT LATE IN THE
WEEK.

WENT WITH A DRY FCST FOR SUNDAY...IT WILL BE CLOSE...HARD TO
SEE THE EAST...WEST COLD FRONT DROPPING TOO FAR SOUTH.

TEMPS WILL BE WARM THROUGHOUT THE PERIOD...ABOVE NORMAL.

&&

.AVIATION /03Z MONDAY THROUGH FRIDAY/...
VFR CONDITIONS PREVAIL ACROSS CENTRAL PENNSYLVANIA. MID CLOUDS
STARTING TO STREAM INTO SOUTHERN TIER COUNTIES AND MAKING THEIR
WAY INTO CENTRAL PA...WITH CIGS 050 TO 100.

EASTERLY FLOW WILL PERSIST OVERNIGHT...AND BRING WITH IT A GRADUAL
INCREASE CLOUDS SPREADING IN FROM THE SOUTHWEST. BY 06Z MVFR CIGS
EXPECTED OVER KMDT AND KLNS...AND BY MONDAY MORNING /12Z/ EXPECT
MVFR CIGS TO OVERSPREAD MUCH OF SOUTHEAST PENNSYLVANIA INTO THE
LAURELS. MOISTURE WILL CONTINUE TO INCREASE ACROSS THE REGION ON
SOUTHEAST LOW LEVEL FLOW...AS DEEP LOW LIFTS INTO THE REGION. MVFR
TO IFR CIGS EXPECTED TO OVERSPREAD MOST OF CENTRAL PENNSYLVANIA BY
14-16Z...WITH INCREASING SHOWERS. EXCEPTION MAY BE FAR NW /KBFD/
WHERE VFR CONDITIONS MAY LINGER INTO LATER AFTERNOON.

OUTLOOK...
MON NIGHT-WED...WIDESPREAD MVFR/IFR CIGS AND VSBYS LIKELY IN
SHOWERS AND SCT TSRA.
THU...PRIMARILY VFR. SCT SHRA/TSTM POSS MAINLY SE.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...GRUMM/FITZGERALD
NEAR TERM...DEVOIR/CERU
SHORT TERM...DEVOIR
LONG TERM...MARTIN
AVIATION...JUNG/DEVOIR

000
FXUS61 KPHI 210145
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
945 PM EDT SUN MAY 20 2012

.SYNOPSIS...
AN AREA OF LOW PRESSURE WILL MOVE INTO THE MID ATLANTIC REGION FROM
THE EAST TONIGHT, THEN DISSIPATE MONDAY. DURING THE EARLY PART OF
THE WEEK, LOW PRESSURE SHOULD LIFT NORTHEASTWARD FROM THE BAHAMAS
FOLLOWED BY TROPICAL STORM ALBERTO. BOTH SYSTEMS ARE EXPECTED TO
REMAIN WELL TO OUR EAST. A SLOW MOVING FRONTAL BOUNDARY IS FORECAST
TO APPROACH FROM THE WEST TUESDAY AND IT WILL INFLUENCE OUR WEATHER
DURING THE MID WEEK PERIOD BEFORE DISSIPATING. HIGH PRESSURE IS
ANTICIPATED TO BUILD INTO OUR REGION FOR FRIDAY AND SATURDAY. A COLD
FRONT FROM THE NORTH MAY ARRIVE SUNDAY.

&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
SOME FOG CONTINUES TO BE MENTIONED FOR AWHILE FOR FAR SOUTHEASTERN
NEW JERSEY BASED ON SOME SURFACE OBSERVATIONS AND ALSO A SPOTTER
REPORT. OUR CONFIDENCE IS LOW REGARDING HOW LONG THE FOG LASTS OR
IF IT ADVECTS FARTHER INLAND AND BECOMES DENSE, THEREFORE WE JUST
RESTRICTED IT CLOSER TO THE COAST THROUGH THE EVENING FOR NOW. IT
APPEARS THE INITIAL DEEPER MOISTURE SURGE, HIGHER DEW POINTS AND
THE FLOW DIRECTLY INTO THE COAST IS HELPING TO DEVELOP THE LOCAL
FOG. WE BELIEVE FARTHER INLAND, IT WILL BE MOSTLY STRATUS. THE
HOURLY GRIDS WERE ADJUSTED BASED ON THE 01Z OBS AND SOME
INCORPORATION OF THE LAMP/LAV GUIDANCE.

OTHERWISE, AN AREA OF LOW PRESSURE WILL CONTINUE TO SLIDE
WESTWARD AND MOVE INTO VIRGINIA THROUGH TONIGHT. THE FLOW AROUND
THIS LOW ALONG WITH HIGH PRESSURE SITUATED TO OUR NORTHEAST WILL
MAINTAIN AN ONSHORE COMPONENT. THE OVERALL FLOW IS FORECAST TO
WEAKEN SOME AS THE GRADIENT SUBSIDES DUE TO THE LOW WEAKENING.
HOWEVER, A PLUME OF MOISTURE WILL ADVECT INTO THE AREA WITH THE
MODEL GUIDANCE INDICATING THE PW VALUES INCREASING TO NEAR 1.5
INCHES OVERNIGHT. THERE APPEARS TO BE AN IMPULSE ROTATING AROUND
THE SURFACE LOW AND THIS LOOKS TO BE WHAT THE MAJORITY OF THE
MODELS ARE KEYING IN ON. THIS RESULTS IN SHOWERS THAT EXPAND FROM
SOUTHEAST TO NORTHWEST ACROSS A GOOD PART OF THE CWA DURING THE
NIGHT. THIS AREA LOOKS TO BE THE SHOWERS THAT ARE MOVING ACROSS
SOUTHERN DELAWARE AS OF 0130Z. THE OVERALL TIMING ON THIS HAS
SOME LOWER CONFIDENCE, HOWEVER GIVEN THE INCREASING MOISTURE SOME
LOCAL DOWNPOURS WILL BE QUITE POSSIBLE ESPECIALLY OVERNIGHT. AS A
RESULT, THE POPS INCREASE FROM SOUTHEAST TO NORTHWEST DURING THE
COURSE OF THE NIGHT. BASED ON THE DEEPENING MOISTURE AND LOWERING
CLOUD BASES, SOME DRIZZLE CANNOT BE RULED OUT.

THERE IS NOT A LOT OF INSTABILITY FORECAST TO OCCUR, THEREFORE
JUST A SLIGHT CHC OF THUNDER /ISOLATED/ WAS CARRIED ACROSS
PORTIONS OF THE FAR SOUTHEASTERN CWA FOR AWHILE TONIGHT GIVEN THAT
SOME CONVECTION CONTINUES OFF THE MARYLAND COAST AND IS MOVING
NORTHWESTWARD AS OF 0130Z.

&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/...
MDL SOLNS DIFFER A BIT ON PRECIP TOMORROW. WE WILL STILL BE
IMPACTED BY THE AFOREMENTIONED LOW, BUT IT WILL NOT BE A
COMPLETELY RAINY DAY BY ANY MEANS. THERE WILL BE SHOWERS
AS PIECES OF ENERGY ROTATE AROUND THE LOW. AS A RESULT, THE MDLS
ARE HAVING THEIR DIFFS DETERMINING WHICH PDS WILL BE WET AND WHICH
ONES WILL BE DRY. THERE ARE SOME INDICATIONS THAT THE MORNING
COULD BE WETTER THAN THE AFTN, OVERALL. QPF SHOULD BE 0.50 INCHES
OR LESS.

&&

.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
THE EFFECTS OF TROPICAL STORM ALBERTO SHOULD REMAIN TO OUR EAST
AND WILL LIKELY NOT INFLUENCE OUR LAND AREAS. NEVERTHELESS, THE
WEATHER IS GOING TO BE RATHER UNSETTLED FROM MONDAY NIGHT INTO
THURSDAY. THERE WILL BE A RELATIVELY LIGHT FLOW NEAR THE SURFACE
AS WELL AS IN THE MID AND UPPER LEVELS OF THE ATMOSPHERE DURING
MUCH OF THE PERIOD. A FAIR AMOUNT OF LOW LEVEL MOISTURE SHOULD
LINGER IN OUR REGION. AS A RESULT, CLOUDS AND SCATTERED SHOWERS
ARE ANTICIPATED.

A SLOW MOVING BOUNDARY FROM THE WEST SHOULD BEGIN TO APPROACH
FROM THE WEST ON TUESDAY BEFORE MOVING INTO OUR VICINITY FOR
TUESDAY NIGHT AND WEDNESDAY. THE FRONT IS EXPECTED TO DISSIPATE
GRADUALLY.

WITH DAYTIME HEATING, THERE WILL BE AN INCREASE IN INSTABILITY
DURING THE AFTERNOON AND EVENING HOURS ON TUESDAY AND WEDNESDAY,
ESPECIALLY AT LOCATIONS A BIT REMOVED FROM THE OCEAN INFLUENCE. AS
A RESULT, WE WILL INDICATE AT CHANCE OF AFTERNOON AND EVENING
THUNDERSTORMS ON BOTH DAYS, EXCEPT NEAR THE COAST.

WITH THE REMNANTS OF THE BOUNDARY IN OR NEAR OR REGION ON
THURSDAY AND WITH A MID LEVEL TROUGH OR LOW PASSING NEARBY OR
OVERHEAD, WE WILL AGAIN CARRY A CHANCE OF SHOWERS AND
THUNDERSTORMS.

DUE TO THE LIGHT ATMOSPHERIC FLOW, ANY SHOWERS AND THUNDERSTORMS
ON TUESDAY, WEDNESDAY AND THURSDAY MAY BE SLOW MOVING AND THEY
COULD LEAVE MODERATE TO HEAVY RAINFALL AT SOME LOCATIONS.

HIGH PRESSURE IS EXPECTED TO PUSH INTO OUR REGION FROM THE
NORTHEAST FOR FRIDAY AND SATURDAY WITH A TREND TOWARD DRY WEATHER
ANTICIPATED. A FRONTAL BOUNDARY FROM THE NORTHWEST MAY ARRIVE ON
SATURDAY NIGHT OR SUNDAY.

TEMPERATURES SHOULD BE NEAR OR SLIGHTLY ABOVE NORMAL FOR THIS
TIME OF THE YEAR FROM MONDAY NIGHT THROUGH THURSDAY NIGHT. WITH
DRY AIR BUILDING INTO OUR REGION, ABOVE NORMAL TEMPERATURES ARE
EXPECTED FOR FRIDAY INTO THE WEEKEND, EVEN WITH THE ARRIVAL OF THE
FRONTAL BOUNDARY FROM THE NORTHWEST.

&&

.AVIATION /02Z MONDAY THROUGH FRIDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.

THE AIRMASS WILL CONTINUE TO MOISTEN FROM EAST TO WEST TONIGHT,
THEREFORE THE LOWERING CLOUD BASES WILL MIGRATE INLAND. THE MAIN
FORECAST CHALLENGES ARE HOW QUICKLY THIS OCCURS AND HOW LOW THE
CEILINGS END UP GETTING. AS THE SURFACE TEMPERATURES CONTINUE TO
COOL, THE CLOUDS WILL LOWER FROM EAST TO WEST. THIS IS ALREADY
OCCURRING WITH IFR CEILINGS IN THE KACY AREAS WITH MVFR TO THE
KPHL METRO AREA. THESE LOWERING CEILINGS WILL CONTINUE WESTWARD
AND WE BOUGHT ALL OF OUR TERMINALS DOWN TO MVFR THEN EVEN TO IFR,
WITH KABE AND KRDG SEEING THE LATTER LAST.

THERE WILL BE SHOWERS DEVELOPING AS WELL GENERALLY FROM SOUTHEAST TO
NORTHWEST DURING THE COURSE OF THE NIGHT. THERE IS LOWER CONFIDENCE
ON THE TIMING AND COVERAGE OF THESE, HOWEVER GIVEN THE DEEPENING
MOISTURE THROUGH THE NIGHT, LOCAL DOWNPOURS WILL BE POSSIBLE. THE
MAIN SHOWERS LOOK TO BE WHAT IS MOVING ACROSS SOUTHERN DELAWARE
AND OFFSHORE OF SOUTHEASTERN NEW JERSEY AS OF 0130Z. THE THUNDER
CHANCES SEEM TO BE RATHER LOW, THEREFORE NO MENTION WAS INCLUDED
AT THIS TIME. THE NORTHEAST TO EAST WINDS WILL SETTLE THROUGH THE
NIGHT GENERALLY TO ABOUT 10 KNOTS, AS THE PRESSURE GRADIENT
WEAKENS SOME DUE TO THE LOW PRESSURE SYSTEM TO OUR SOUTH
WEAKENING. THE MOISTURE APPEARS TO BE DEEP ENOUGH ALREADY AND WITH
THE SURFACE DEW POINTS COMING UP SOME THAT SOME FOG HAS DEVELOPED
EARLY THIS EVENING FROM ABOUT KACY TO KWWD. WE HAVE LOWER
CONFIDENCE IF THIS SPREADS INLAND, THEREFORE WE RESTRICTED IT AT
KACY TO NEAR KMIV FOR AWHILE TONIGHT.

FOR MONDAY, SUB-VFR CONDITIONS ARE EXPECTED TO CONTINUE AS A
WEAKNESS IN THE ATMOSPHERE REMAINS IN PLACE ALONG WITH AN ABUNDANCE
OF MOISTURE. THERE SHOULD BE LOWER CLOUDS AND PERHAPS A TOUCH OF FOG
IN THE MORNING ALONG WITH SHOWERS, THE THERE MAY BE A LULL IN THE
SHOWERS FOR AWHILE. AGAIN, THERE IS LOWER CONFIDENCE REGARDING
THE TIMING AND COVERAGE OF THE SHOWERS. WHILE SOME THUNDERSTORMS ARE
POSSIBLE, THEY DO NOT APPEAR TO BE ALL THAT WIDESPREAD, THEREFORE
THIS WAS NOT INCLUDED AT THIS TIME. THE WINDS WILL GENERALLY BE FROM
THE EAST AROUND 10 KNOTS.

OUTLOOK...
MONDAY NIGHT THROUGH THURSDAY...MVFR/IFR CEILING AND VISIBILITY
VALUES ARE POSSIBLE, ALONG WITH SCATTERED SHOWERS, DURING THE
OVERNIGHT AND MORNING HOURS EACH DAY. MAINLY VFR CONDITIONS ARE
EXPECTED DURING THE AFTERNOON AND EVENING HOURS, EXCEPT IN
SCATTERED SHOWERS AND THUNDERSTORMS. THE WIND SHOULD BE MAINLY 10
KNOTS OR LESS AND IT MAY FAVOR THE EAST TO SOUTH QUADRANT.

THURSDAY NIGHT AND FRIDAY...MAINLY VFR WITH A SOUTH WIND 10 KNOTS
OR LESS. SOME LATE NIGHT AND EARLY MORNING VISIBILITY RESTRICTIONS
ARE POSSIBLE.

&&

.MARINE...
THE WINDS ACROSS LOWER DELAWARE ARE STRONGEST MAINLY NEAR THE
LEWES AREA DUE TO THE NORTHEAST FETCH PROBABLY BEING ENHANCED SOME
ACROSS THE MOUTH OF THE BAY. WE WILL KEEP THE ADVISORY HERE UNTIL
MIDNIGHT FOR NOW.

PROLONGED NORTHEAST TO EAST FLOW IS EXPECTED THROUGH MONDAY AS LOW
PRESSURE WEAKENS ACROSS THE MID ATLANTIC. SEAS WILL REMAIN AT OR
ABOVE 5 FEET WITH THE HIGHER SETS ACROSS THE SOUTHERN WATERS DUE TO
A LONGER FETCH AND INITIALLY STRONGER WINDS. THE SMALL CRAFT ADVISORY
REMAINS IN EFFECT AS A RESULT THROUGH MONDAY. THE WINDS WILL GUST
THROUGH THIS EVENING, ESPECIALLY ACROSS THE SOUTHERN WATERS, THEN
TEND TO DIMINISH SOME LATER TONIGHT AS THE PRESSURE GRADIENT BEGINS
TO RELAX SOME.

OUTLOOK...
WIND SPEEDS ARE FORECAST TO REMAIN BELOW THE SMALL CRAFT ADVISORY
CRITERION FOR THE PERIOD FROM MONDAY NIGHT THROUGH FRIDAY.

WAVE HEIGHTS ON OUR OCEAN WATERS ARE EXPECTED TO REMAIN AT 5 FEET
OR GREATER INTO THE MID WEEK PERIOD, AS TROPICAL STORM ALBERTO
PASSES WELL TO OUR EAST. FOR NOW, THE SMALL CRAFT ADVISORY ON OUR
OCEAN WATERS HAS BEEN EXTENDED UNTIL 600 AM TUESDAY.

&&

.TIDES/COASTAL FLOODING...
TIDES MAY NEAR MINOR COASTAL FLOODING THRESHOLDS OVERNIGHT IN UPPER
DELAWARE BAY. OTHERWISE, ALL OTHER AREAS ARE EXPECTED TO REMAIN
UNDER CRITERIA.

&&

.RIP CURRENTS...
WHILE THE ONSHORE FLOW WILL PERSIST MONDAY, IT IS FORECAST TO NOT
BE AS STRONG AS SUNDAY. IN ADDITION, THE SEAS ARE FORECAST TO BE
SOMEWHAT LOWER. BASED ON THIS, WE CAME UP WITH A MODERATE RISK OF
RIP CURRENTS FOR MONDAY.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT TUESDAY FOR ANZ452>455.
     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 AM EDT TUESDAY
     FOR ANZ450-451.
     SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR ANZ431.

&&

$$
SYNOPSIS...GORSE/IOVINO
NEAR TERM...GORSE
SHORT TERM...NIERENBERG
LONG TERM...IOVINO
AVIATION...GORSE/IOVINO
MARINE...GORSE/IOVINO
TIDES/COASTAL FLOODING...GORSE/HAYES
RIP CURRENTS...GORSE

000
FXUS61 KPBZ 210138
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
938 PM EDT SUN MAY 20 2012

.SYNOPSIS...
BY MONDAY AFTERNOON...THE REGION WILL BE SQUEEZED BY AREAS OF
PRECIPITATION FROM THE WEST AND EAST. THE BEST CHANCE FOR SHOWERS
WILL BE ON TUESDAY. HIGH PRESSURE WILL BRING DRY WEATHER FOR
WEDNESDAY AND THURSDAY.

&&

.NEAR TERM /THROUGH MONDAY/...
UPDATE FOR MINOR ADJUSTMENTS TO SKY COVER. ALTHOUGH TROPICAL STORM
ALBERTO OFF THE COAST OF SOUTH CAROLINA HAS BEEN THE MAIN WEATHER
FOCUS IN THE LAST DAY...AN EXTRATROPICAL STORM OFF THE VIRGINIA
COAST WILL BE ONE OF THE PRIMARY FACTORS IN THE LOCAL FORECAST FOR
THE NEXT 48 HOURS. HIGH PRESSURE RIDGE CURRENTLY OVER THE REGION
WILL BE PUSHED OFF TO THE NORTHEAST OVERNIGHT...WITH THE VIRGINIA
LOW SLOWLY MOVING ONSHORE DURING THAT TIME PERIOD. WITH THE SLOW
PROGRESS...ONLY A SLIGHT CHANCE OF SHOWERS FOR THE RIDGES IS
FORECAST LATE TONIGHT. MEANWHILE...A COLD FRONT CURRENTLY
STRETCHING FROM UPPER MICHIGAN SOUTH INTO MISSOURI WILL MOVE
EAST...MOVING INTO INDIANA BY MONDAY MORNING.

TO THE EAST...LOW PRESSURE WILL SLOWLY DISSIPATE AS IT MOVES INTO
CENTRAL PENNSYLVANIA...THEN VEERS INTO NEW YORK. THIS WILL INCREASE
THE CHANCE OF SHOWERS AND THUNDERSTORMS FROM EAST TO WEST...BUT
LIKELY POPS WILL REMAIN EAST OF US. AT THE SAME TIME...THE COLD
FRONT WILL APPROACH THE WESTERN EDGE OF THE FORECAST AREA BY LATE
MONDAY AFTERNOON. ALTHOUGH INSTABILITY VALUES WILL BE LIGHT TO
MODERATE...WIND PROFILES UP TO 25 KFT ARE NEARLY CALM...WHICH SHOULD
PREVENT ANY CHANCE FOR SEVERE WEATHER. WITH CLOUD COVER
OVERSPREADING EASTERN COUNTIES THE MOST...LOWS WILL BE HELD TO THE
LOW AND MID 70S EAST...WITH MID 80S STILL POSSIBLE WEST.

&&

.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
COLD FRONT WILL CONTINUE TO PROGRESS EAST MONDAY NIGHT...BUT WITH
LITTLE IN THE WAY OF DEEP MOISTURE. WILL CONTINUE CHANCE POPS MONDAY
NIGHT INTO TUESDAY...WITH LIKELY POPS ONLY MENTIONED ACROSS THE
RIDGES TUESDAY AFTERNOON WHERE OROGRAPHIC LIFT SHOULD HELP TO
GENERATE SHOWERS. INSTABILITY STILL LOOKS QUITE LIMITED...AND HAVE
CONTAINED THUNDER MENTION ONLY TO LOCATIONS WITH LIKELY POPS. WITH
WIDESPREAD CLOUD COVER...HIGHS EVERYWHERE WILL DROP BACK TO
SEASONABLE LEVELS.

BY TUESDAY NIGHT...THE UPPER LEVEL TROUGH ASSOCIATED WITH THE COLD
FRONT IS EXPECTED TO CLOSE OFF INTO AN UPPER LOW OVER THE CAROLINAS
AND REMAIN STATIONARY INTO WEDNESDAY. THE CUTOFF FLOW IS EXPECTED TO
KEEP SKIES PARTLY/MOSTLY CLOUDY...WITH A CHANCE OF SHOWERS
CONTINUING TO PERSIST. WITH SOME BREAKS IN CLOUD COVER...HIGHS WILL
RISE A COUPLE OF DEGREES FROM TUESDAY/S VALUES.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
A NEARLY STATIONARY UPPER LEVEL LOW/TROUGH WILL BE NEAR THE
CAROLINAS. HOWEVER...MODEL SOLUTIONS DIFFER. AT THIS TIME ENSEMBLE
TREND IS STILL TO KEEP A DRIER FORECAST FOR THE COUNTY WARNING
AREA...SO WILL CONTINUE THE TREND. THE PERIOD IS PROJECTED TO BE
WARM WITH ABOVE AVERAGE TEMPERATURES APPROACHING 90 DEGREES AND
SFC DEWPOINTS IN THE LOW TO MID 60S FOR THE START OF THE MEMORIAL
DAY WEEKEND.

&&

.AVIATION /02Z MONDAY THROUGH FRIDAY/...
VFR CONDITIONS WILL PREVAIL ACROSS THE TERMINALS THROUGH TOMORROW
MORNING AS HIGH PRESSURE SHIFTS NORTHEAST OF THE AREA.

LOW PRESSURE WILL PULL ATLANTIC MOISTURE INTO THE AREA FROM THE
SOUTHEAST AND A FRONTAL BOUNDARY WILL APPROACH FROM THE WEST
TOMORROW AFTERNOON. THIS WILL MAKE ISOLATED SHOWERS AND
THUNDERSTORMS WITH MVFR RESTRICTIONS POSSIBLE ACROSS THE TERMINALS
LATE TOMORROW AFTERNOON INTO THE EVENING. WITH ISOLATED COVERAGE,
-TSRA IS NOT MENTIONED IN THE TAFS AT THIS POINT. NEAR CALM WINDS
OVERNIGHT WILL BECOME SOUTHEASTERLY AT AROUND 5KTS TOMORROW.

.OUTLOOK...MONDAY NIGHT THROUGH FRIDAY...
MOISTURE WILL INCREASE FROM THE EAST AS LOW PRESSURE MOVES UP THE
EASTERN SEABOARD. AN INCREASE IN LOW LEVEL MOISTURE MAY SET OFF
ISOLATED SHOWERS AND THUNDERSTORMS WITH RESTRICTIONS MONDAY NIGHT
THROUGH WEDNESDAY. SFC DEWPOINTS WILL INCREASE THROUGH THE PERIOD
AND WILL RESULT IN VISIBILITY RESTRICTIONS DUE TO HZ/BR AT MOST
AIRPORT LOCATIONS DURING THE EARLY MORNING HOURS WEDNESDAY AND
THURSDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$

000
FXUS61 KCTP 210054
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
854 PM EDT SUN MAY 20 2012

.SYNOPSIS...
HIGH PRESSURE WILL PUSH WELL OFF THE COASTAL NEW ENGLAND WATERS
TONIGHT. AN INCREASING MOIST EAST TO SOUTHEAST FLOW WILL PUSH
ATLANTIC MOISTURE INTO CENTRAL PENNSYLVANIA LATE TONIGHT AND
MONDAY...AS AN UPPER LEVEL TROF MOVES TO THE CENTRAL GREAT LAKES
ON MONDAY. THIS WILL BRING AN INCREASING CHANCE OF SHOWERS TO ALL
OF CENTRAL PA ON MONDAY. AN UPPER LEVEL LOW OVER THE SOUTHEAST
WILL SLOWLY TRACK NORTHEASTWARD THROUGH MID WEEK...KEEPING
UNSETTLED WEATHER ALONG THE EASTERN SEABOARD...AND A DAILY CHANCE
OF SHOWERS AND THUNDERSTORMS OVER CENTRAL PENNSYLVANIA.
PENNSYLVANIA WILL BE ON THE EDGE OF A BUILDING A LARGE UPPER HIGH
ACROSS THE TENNESSEE RIVER VALLEY AND SOUTHEASTERN STATES BY THE
END OF THIS WEEK.

&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
CLEAR SKIES SHOULD PREVAIL FOR MOST OF CENTRAL PA THIS
EVENING...WITH LOW CLOUDS APPROACHING LATE THIS EVENING ACROSS
LANCASTER AND YORK COUNTIES. CLOUDS WILL CONTINUE THEIR TREK
WESTWARD AND NORTHWARD...EVENTUALLY OVERSPREADING MOST IF NOT ALL
OF CENTRAL PA BY 15Z MON. FAR NORTHWEST AREAS MAY ESCAPE BKN CIGS.
ALL BUT THE LOWER SUSQ. SHOULD REMAIN DRY TONIGHT...BUT AREAS OF
DRIZZLE AND LIGHT SHOWERS ARE CERTAINLY POSSIBLE IN THE DEEPER
MARITIME AIR MASS OVER THE LOWER SUSQ RIVER VALLEY BEFORE 12Z.
OVERNIGHT MINS WILL BE MUCH MILDER WITH THE INCREASING CLOUD
COVER...AND WILL RANGE FROM THE LOWER 50S IN THE NORTH TO THE MID
TO UPPER 50S SOUTHEAST.

&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/...
NO CHANGES TO THE THINKING ON MONDAY AS UPPER LOW OVER THE
SOUTHEAST CONUS WILL LIFT NORTH ALONG THE E COAST. ASSOCIATED
MOIST...EASTERLY LL JET AND UPPER LVL DIVERGENCE PRECEDING THE
UPPER LOW WILL LIKELY BRING SCT SHOWERS TO CENTRAL PA BEGINNING
LATE TONIGHT ACROSS THE SOUTHEAST ZONES AND OVERSPREADING THE
REST OF CENTRAL PA DURING MONDAY. CLOUD COVER...PRECIP AND
EASTERLY FLOW OFF THE ATLANTIC WILL RESULT IN A MUCH COOLER
MONDAY WITH MAX TEMPS ONLY ARND 70F. GEFS DATA SHOWING HIGHEST
PWATS ACROSS SOUTHEAST PA...WHERE THE BEST CHC OF MEASURABLE
RAINFALL IS EXPECTED SUN NITE/MONDAY.

DOWNSLOPING SE FLOW WILL RESULT IN PARTIAL SUNSHINE AND A
SOMEWHAT WARMER MONDAY OVR WARREN COUNTY...WHERE A LATE DAY
TSRA IS POSSIBLE. CAPE VALUES IN THE 600 TO 800JK-1 RANGE
ACROSS WARREN CO MON EVENING. FURTHER EAST...A COOLER MORE
STABLE EASTERLY FLOW SHOULD PRECLUDE THUNDER.

&&

.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
NOT A LOT OF CHANGE FROM THE FCST PACKAGE YESTERDAY.

STILL LOOKS LIKE NORTHERN SYSTEM OFF THE COAST WILL PIVOT AROUND
ALBERTO AND MOVE WESTWARD...BRINGING SHOWERS TO THE AREA ON TUE.
MAIN CHC WILL BE MONDAY INTO TUE.

DID UP TEMPS SOME ON TUE...ALSO SOME CHC OF A THUNDERSTORM WITH
THE WARMER TEMPS.

SHOWERS COULD LINGER INTO WED...ESPECIALLY ACROSS THE SE WITH
THE FRONT.

TRIED TO GO WITH THE MID SHIFT FCST AND HAVE SOME PERIODS OF
DRY WEATHER. HARD TO FIND A LOT OF DRY PERIODS...AS REMAINS OF
CUTOFF COULD KEEP A FEW SHOWERS ACROSS EASTERN AREAS...WHERE
FAR NW AREAS COULD SEE SOME FROM THE COLD FRONT LATE IN THE
WEEK.

WENT WITH A DRY FCST FOR SUNDAY...IT WILL BE CLOSE...HARD TO
SEE THE EAST...WEST COLD FRONT DROPPING TOO FAR SOUTH.

TEMPS WILL BE WARM THROUGHOUT THE PERIOD...ABOVE NORMAL.

&&

.AVIATION /00Z MONDAY THROUGH FRIDAY/...
VFR CONDITIONS PREVAIL ACROSS CENTRAL PENNSYLVANIA. MID CLOUDS
STARTING TO STREAM INTO SOUTHERN TIER COUNTIES NOW...WITH CIGS 050
TO 100.

EASTERLY FLOW WILL PERSIST OVERNIGHT...AND BRING WITH IT A GRADUAL
INCREASE CLOUDS SPREADING IN FROM THE SOUTHWEST. BY 06Z MVFR CIGS
EXPECTED OVER KMDT AND KLNS...AND BY MONDAY MORNING /12Z/ EXPECT
MVFR CIGS TO OVERSPREAD MUCH OF SOUTHEAST PENNSYLVANIA INTO THE
LAURELS. MOISTURE WILL CONTINUE TO INCREASE ACROSS THE REGION ON
SOUTHEAST LOW LEVEL FLOW...AS DEEP LOW LIFTS INTO THE REGION. MVFR
TO IFR CIGS EXPECTED TO OVERSPREAD MOST OF CENTRAL PENNSYLVANIA BY
14-16Z...WITH INCREASING SHOWERS. EXCEPTION MAY BE FAR NW /KBFD/
WHERE VFR CONDITIONS MAY LINGER INTO LATER AFTERNOON.

OUTLOOK...
MON NIGHT-WED...WIDESPREAD MVFR/IFR CIGS AND VSBYS LIKELY IN
SHOWERS AND SCT TSRA.
THU...PRIMARILY VFR. SCT SHRA/TSTM POSS MAINLY SE.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...GRUMM/FITZGERALD
NEAR TERM...DEVOIR/CERU
SHORT TERM...DEVOIR
LONG TERM...MARTIN
AVIATION...JUNG/DEVOIR

000
FXUS61 KPHI 210028
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
828 PM EDT SUN MAY 20 2012

.SYNOPSIS...
AN AREA OF LOW PRESSURE WILL MOVE INTO THE MID ATLANTIC REGION FROM
THE EAST TONIGHT, THEN DISSIPATE MONDAY. DURING THE EARLY PART OF
THE WEEK, LOW PRESSURE SHOULD LIFT NORTHEASTWARD FROM THE BAHAMAS
FOLLOWED BY TROPICAL STORM ALBERTO. BOTH SYSTEMS ARE EXPECTED TO
REMAIN WELL TO OUR EAST. A SLOW MOVING FRONTAL BOUNDARY IS FORECAST
TO APPROACH FROM THE WEST TUESDAY AND IT WILL INFLUENCE OUR WEATHER
DURING THE MID WEEK PERIOD BEFORE DISSIPATING. HIGH PRESSURE IS
ANTICIPATED TO BUILD INTO OUR REGION FOR FRIDAY AND SATURDAY. A COLD
FRONT FROM THE NORTH MAY ARRIVE SUNDAY.

&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
A QUICK UPDATE HAS BEEN ISSUED TO ADJUST THE POPS A BIT AND ALSO
THE SKY COVER. IN ADDITION, SOME FOG WAS ADDED FOR FAR
SOUTHEASTERN NEW JERSEY BASED ON SOME SURFACE OBSERVATIONS AND
ALSO A SPOTTER REPORT. OUR CONFIDENCE IS LOW REGARDING HOW LONG THE
FOG LASTS OR IF IT ADVECT FARTHER INLAND, THEREFORE WE JUST
RESTRICTED IT CLOSER TO THE COAST THROUGH THE EVENING FOR NOW. IT
APPEARS THE INITIAL DEEPER MOISTURE SURGE, HIGHER DEW POINTS AND
THE FLOW DIRECTLY INTO THE COAST IS HELPING TO DEVELOP THE LOCAL
FOG. WE BELIEVE FARTHER INLAND, IT WILL BE MORE STRATUS. THE
HOURLY GRIDS WERE ADJUSTED BASED ON THE 00Z OBS AND SOME
INCORPORATION OF THE LAMP/LAV GUIDANCE.

OTHERWISE, AN AREA OF LOW PRESSURE WILL CONTINUE TO SLIDE
WESTWARD AND MOVE INTO VIRGINIA THROUGH TONIGHT. THE FLOW AROUND
THIS LOW ALONG WITH HIGH PRESSURE SITUATED TO OUR NORTHEAST WILL
MAINTAIN AN ONSHORE COMPONENT. THE OVERALL FLOW IS FORECAST TO
WEAKEN SOME AS THE GRADIENT SUBSIDES DUE TO THE LOW WEAKENING.
HOWEVER, A PLUME OF MOISTURE WILL ADVECT INTO THE AREA WITH THE
MODEL GUIDANCE INDICATING THE PW VALUES INCREASING TO NEAR 1.5
INCHES OVERNIGHT. THERE APPEARS TO BE AN IMPULSE ROTATING AROUND
THE SURFACE LOW AND THIS LOOKS TO BE WHAT THE MAJORITY OF THE
MODELS ARE KEYING IN ON. THIS RESULTS IN SHOWERS THAT EXPAND FROM
SOUTHEAST TO NORTHWEST ACROSS A GOOD PART OF THE CWA DURING THE
NIGHT. THIS AREA LOOKS TO BE THE SHOWERS THAT ARE MOVING ACROSS
SOUTHERN DELAWARE AS OF 0000Z. THE OVERALL TIMING ON THIS HAS SOME
LOWER CONFIDENCE, HOWEVER GIVEN THE INCREASING MOISTURE SOME LOCAL
DOWNPOURS WILL BE QUITE POSSIBLE ESPECIALLY OVERNIGHT. AS A
RESULT, THE POPS INCREASE FROM SOUTHEAST TO NORTHWEST DURING THE
COURSE OF THE NIGHT.

THE MOISTENING ONSHORE FLOW WILL ALSO RESULT IN LOW CLOUDS SPREADING
INLAND THROUGH THE NIGHT. AS THE BOUNDARY LAYER CONTINUES TO COOL,
THE CLOUDS WILL LOWER FROM EAST TO WEST. THERE IS NOT A LOT OF
INSTABILITY FORECAST TO OCCUR, THEREFORE JUST A CHC OF THUNDER WAS
MENTIONED ACROSS PORTIONS OF THE SOUTHEASTERN CWA FOR AWHILE
TONIGHT GIVEN THAT SOME CONVECTION HAS BEEN TIED CLOSER TO THE
SURFACE LOW CENTER ATTM.

&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/...
MDL SOLNS DIFFER A BIT ON PRECIP TOMORROW. WE WILL STILL BE
IMPACTED BY THE AFOREMENTIONED LOW, BUT IT WILL NOT BE A
COMPLETELY RAINY DAY BY ANY MEANS. THERE WILL BE SHOWERS
AS PIECES OF ENERGY ROTATE AROUND THE LOW. AS A RESULT, THE MDLS
ARE HAVING THEIR DIFFS DETERMINING WHICH PDS WILL BE WET AND WHICH
ONES WILL BE DRY. THERE ARE SOME INDICATIONS THAT THE MORNING
COULD BE WETTER THAN THE AFTN, OVERALL. QPF SHOULD BE 0.50 INCHES
OR LESS.

&&

.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
THE EFFECTS OF TROPICAL STORM ALBERTO SHOULD REMAIN TO OUR EAST
AND WILL LIKELY NOT INFLUENCE OUR LAND AREAS. NEVERTHELESS, THE
WEATHER IS GOING TO BE RATHER UNSETTLED FROM MONDAY NIGHT INTO
THURSDAY. THERE WILL BE A RELATIVELY LIGHT FLOW NEAR THE SURFACE
AS WELL AS IN THE MID AND UPPER LEVELS OF THE ATMOSPHERE DURING
MUCH OF THE PERIOD. A FAIR AMOUNT OF LOW LEVEL MOISTURE SHOULD
LINGER IN OUR REGION. AS A RESULT, CLOUDS AND SCATTERED SHOWERS
ARE ANTICIPATED.

A SLOW MOVING BOUNDARY FROM THE WEST SHOULD BEGIN TO APPROACH
FROM THE WEST ON TUESDAY BEFORE MOVING INTO OUR VICINITY FOR
TUESDAY NIGHT AND WEDNESDAY. THE FRONT IS EXPECTED TO DISSIPATE
GRADUALLY.

WITH DAYTIME HEATING, THERE WILL BE AN INCREASE IN INSTABILITY
DURING THE AFTERNOON AND EVENING HOURS ON TUESDAY AND WEDNESDAY,
ESPECIALLY AT LOCATIONS A BIT REMOVED FROM THE OCEAN INFLUENCE. AS
A RESULT, WE WILL INDICATE AT CHANCE OF AFTERNOON AND EVENING
THUNDERSTORMS ON BOTH DAYS, EXCEPT NEAR THE COAST.

WITH THE REMNANTS OF THE BOUNDARY IN OR NEAR OR REGION ON
THURSDAY AND WITH A MID LEVEL TROUGH OR LOW PASSING NEARBY OR
OVERHEAD, WE WILL AGAIN CARRY A CHANCE OF SHOWERS AND
THUNDERSTORMS.

DUE TO THE LIGHT ATMOSPHERIC FLOW, ANY SHOWERS AND THUNDERSTORMS
ON TUESDAY, WEDNESDAY AND THURSDAY MAY BE SLOW MOVING AND THEY
COULD LEAVE MODERATE TO HEAVY RAINFALL AT SOME LOCATIONS.

HIGH PRESSURE IS EXPECTED TO PUSH INTO OUR REGION FROM THE
NORTHEAST FOR FRIDAY AND SATURDAY WITH A TREND TOWARD DRY WEATHER
ANTICIPATED. A FRONTAL BOUNDARY FROM THE NORTHWEST MAY ARRIVE ON
SATURDAY NIGHT OR SUNDAY.

TEMPERATURES SHOULD BE NEAR OR SLIGHTLY ABOVE NORMAL FOR THIS
TIME OF THE YEAR FROM MONDAY NIGHT THROUGH THURSDAY NIGHT. WITH
DRY AIR BUILDING INTO OUR REGION, ABOVE NORMAL TEMPERATURES ARE
EXPECTED FOR FRIDAY INTO THE WEEKEND, EVEN WITH THE ARRIVAL OF THE
FRONTAL BOUNDARY FROM THE NORTHWEST.

&&

.AVIATION /00Z MONDAY THROUGH FRIDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.

THE AIRMASS WILL CONTINUE TO MOISTEN FROM EAST TO WEST TONIGHT,
THEREFORE THE LOWER CLOUDS WILL MIGRATE INLAND. THE MAIN FORECAST
CHALLENGES ARE HOW QUICKLY THIS OCCURS AND HOW LOW THE CEILINGS
END UP GETTING. AS THE SURFACE TEMPERATURES CONTINUE TO COOL, THE
CLOUDS WILL LOWER FROM EAST TO WEST. AS A RESULT, WE ARE EXPECTING
THE CEILINGS TO LOWER THROUGH THE NIGHT. WE BROUGHT ALL OF OUR
TERMINALS DOWN TO MVFR THEN EVEN TO IFR, WITH KABE AND KRDG SEEING
THE LATTER LAST.

THERE WILL BE SHOWERS DEVELOPING AS WELL GENERALLY FROM SOUTHEAST TO
NORTHWEST DURING THE COURSE OF THE NIGHT. THERE IS LOWER CONFIDENCE
ON THE TIMING AND COVERAGE OF THESE, HOWEVER GIVEN THE DEEPENING
MOISTURE THROUGH THE NIGHT, LOCAL DOWNPOURS WILL BE POSSIBLE. THE
MAIN SHOWERS LOOK TO BE WHAT IS MOVING ACROSS SOUTHERN DELAWARE
AND OFFSHORE OF SOUTHEASTERN NEW JERSEY AS OF 0000Z. THE THUNDER
CHANCES SEEM TO BE RATHER LOW, THEREFORE NO MENTION WAS INCLUDED
AT THIS TIME. THE NORTHEAST TO EAST WINDS WILL SETTLE THROUGH THE
NIGHT GENERALLY TO ABOUT 10 KNOTS, AS THE PRESSURE GRADIENT
WEAKENS SOME DUE TO THE LOW PRESSURE SYSTEM TO OUR SOUTH
WEAKENING. THE MOISTURE APPEARS TO BE DEEP ENOUGH ALREADY AND
WITH THE SURFACE DEW POINTS COMING UP SOME THAT SOME FOG HAS
DEVELOPED EARLY THIS EVENING FROM ABOUT KACY TO KWWD. WE HAVE LOWER
CONFIDENCE IF THIS SPREADS INLAND, THEREFORE WE RESTRICTED IT AT
KACY TO NEAR KMIV FOR AWHILE TONIGHT.

FOR MONDAY, SUB-VFR CONDITIONS ARE EXPECTED TO CONTINUE AS A
WEAKNESS IN THE ATMOSPHERE REMAINS IN PLACE ALONG WITH AN ABUNDANCE
OF MOISTURE. THERE SHOULD BE LOWER CLOUDS AND PERHAPS A TOUCH OF FOG
IN THE MORNING ALONG WITH SHOWERS, THE THERE MAY BE A LULL IN THE
SHOWERS FOR AWHILE. AGAIN, THERE IS LOWER CONFIDENCE REGARDING
THE TIMING AND COVERAGE OF THE SHOWERS. WHILE SOME THUNDERSTORMS ARE
POSSIBLE, THEY DO NOT APPEAR TO BE ALL THAT WIDESPREAD, THEREFORE
THIS WAS NOT INCLUDED AT THIS TIME. THE WINDS WILL GENERALLY BE FROM
THE EAST AROUND 10 KNOTS.

OUTLOOK...
MONDAY NIGHT THROUGH THURSDAY...MVFR/IFR CEILING AND VISIBILITY
VALUES ARE POSSIBLE, ALONG WITH SCATTERED SHOWERS, DURING THE
OVERNIGHT AND MORNING HOURS EACH DAY. MAINLY VFR CONDITIONS ARE
EXPECTED DURING THE AFTERNOON AND EVENING HOURS, EXCEPT IN
SCATTERED SHOWERS AND THUNDERSTORMS. THE WIND SHOULD BE MAINLY 10
KNOTS OR LESS AND IT MAY FAVOR THE EAST TO SOUTH QUADRANT.

THURSDAY NIGHT AND FRIDAY...MAINLY VFR WITH A SOUTH WIND 10 KNOTS
OR LESS. SOME LATE NIGHT AND EARLY MORNING VISIBILITY RESTRICTIONS
ARE POSSIBLE.

&&

.MARINE...
THE SMALL CRAFT ADVISORY FOR UPPER DELAWARE BAY HAS BEEN CANCELLED.
THE PRESSURE GRADIENT IS FORECAST TO RELAX SOME THROUGH THE NIGHT AS
LOW PRESSURE MOVES INLAND AND ALSO BEGINS TO WEAKEN. THE WINDS HAVE
NOT BEEN REACHING CRITERIA ACROSS THE UPPER BAY AND THEY SHOULD NOT
INCREASE TO THESE LEVELS TONIGHT. THE WINDS ACROSS LOWER DELAWARE
BAY ARE STRONGER, WITH THE STRONGEST GUSTS MAINLY NEAR THE LEWES
AREA DUE TO THE NORTHEAST FETCH. WE WILL KEEP THE ADVISORY HERE FOR
NOW DUE TO GUSTS TO ABOUT 25 KNOTS NEAR THE MOUTH OF THE BAY.

PROLONGED NORTHEAST TO EAST FLOW IS EXPECTED THROUGH MONDAY AS LOW
PRESSURE WEAKENS ACROSS THE MID ATLANTIC. SEAS WILL REMAIN AT OR
ABOVE 5 FEET WITH THE HIGHER SETS ACROSS THE SOUTHERN WATERS DUE TO
A LONGER FETCH AND INITIALLY STRONGER WINDS. THE SMALL CRAFT ADVISORY
REMAINS IN EFFECT AS A RESULT THROUGH MONDAY. THE WINDS WILL GUST
THROUGH THIS EVENING, ESPECIALLY ACROSS THE SOUTHERN WATERS, THEN
TEND TO DIMINISH SOME LATER TONIGHT AS THE PRESSURE GRADIENT BEGINS
TO RELAX SOME.

OUTLOOK...
WIND SPEEDS ARE FORECAST TO REMAIN BELOW THE SMALL CRAFT ADVISORY
CRITERION FOR THE PERIOD FROM MONDAY NIGHT THROUGH FRIDAY.

WAVE HEIGHTS ON OUR OCEAN WATERS ARE EXPECTED TO REMAIN AT 5 FEET
OR GREATER INTO THE MID WEEK PERIOD, AS TROPICAL STORM ALBERTO
PASSES WELL TO OUR EAST. FOR NOW, THE SMALL CRAFT ADVISORY ON OUR
OCEAN WATERS HAS BEEN EXTENDED UNTIL 600 AM TUESDAY.

&&

.TIDES/COASTAL FLOODING...
IT STILL APPEARS THAT MOST, IF NOT ALL SITES, WILL REMAIN BELOW
MINOR TIDAL FLOODING CRITERIA THROUGH MONDAY /AND BEYOND/. THE BEST
CHANCE FOR REACHING THE THRESHOLD WOULD BE OVER OUR FAR SOUTHERN
COASTAL AREAS DUE TO A STRONGER ONSHORE FLOW AND HIGHER SEAS.

&&

.RIP CURRENTS...
WHILE THE ONSHORE FLOW WILL PERSIST MONDAY, IT IS FORECAST TO NOT
BE AS STRONG AS SUNDAY. IN ADDITION, THE SEAS ARE FORECAST TO BE
SOMEWHAT LOWER. BASED ON THIS, WE CAME UP WITH A MODERATE RISK OF
RIP CURRENTS FOR MONDAY.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT TUESDAY FOR ANZ452>455.
     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 AM EDT TUESDAY
     FOR ANZ450-451.
     SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR ANZ431.

&&

$$
SYNOPSIS...GORSE/IOVINO
NEAR TERM...GORSE
SHORT TERM...NIERENBERG
LONG TERM...IOVINO
AVIATION...GORSE/IOVINO
MARINE...GORSE/IOVINO
TIDES/COASTAL FLOODING...NIERENBERG
RIP CURRENTS...GORSE

000
FXUS61 KCTP 202335
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
735 PM EDT SUN MAY 20 2012

.SYNOPSIS...
HIGH PRESSURE WILL PUSH WELL OFF THE COASTAL NEW ENGLAND WATERS
TONIGHT. AN INCREASING MOIST EAST TO SOUTHEAST FLOW WILL PUSH
ATLANTIC MOISTURE INTO CENTRAL PENNSYLVANIA LATE TONIGHT AND
MONDAY...AS AN UPPER LEVEL TROF MOVES TO THE CENTRAL GREAT LAKES
ON MONDAY. THIS WILL BRING AN INCREASING CHANCE OF SHOWERS TO ALL
OF CENTRAL PA ON MONDAY. AN UPPER LEVEL LOW OVER THE SOUTHEAST
WILL SLOWLY TRACK NORTHEASTWARD THROUGH MID WEEK...KEEPING
UNSETTLED WEATHER ALONG THE EASTERN SEABOARD...AND A DAILY CHANCE
OF SHOWERS AND THUNDERSTORMS OVER CENTRAL PENNSYLVANIA.
PENNSYLVANIA WILL BE ON THE EDGE OF A BUILDING A LARGE UPPER HIGH
ACROSS THE TENNESSEE RIVER VALLEY AND SOUTHEASTERN STATES BY THE
END OF THIS WEEK.

&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
LLVL MOISTURE PUSHING WESTWARD INTO NRN MD FROM DE AND SOUTHERN
NEW JERSEY THIS AFTERNOON AS DEEPER LLVL ELY FLOW CONTS TO DRAW
ATLANTIC MOISTURE INLAND. CLEAR SKIES SHOULD PREVAIL FOR MOST OF
CENTRAL PA THIS EVENING...WITH LOW CLOUDS APPROACHING LATER THIS
EVENING ACROSS LANCASTER AND YORK COUNTIES. AFTER SUNSET...CLOUDS
WILL CONTINUE THEIR TREK WESTWARD AND NORTHWARD...EVENTUALLY
OVERSPREADING MOST IF NOT ALL OF CENTRAL BY BY 12Z MON. FAR
NORTHWEST AREAS MAY ESCAPE BKN CIGS. ALL BUT THE LOWER SUSQ. SHOULD
REMAIN DRY TONIGHT...BUT AREAS OF DRIZZLE AND LIGHT SHOWERS ARE
CERTAINLY POSSIBLE IN THE DEEPER MARITIME AIR MASS OVER THE LOWER
SUSQ RIVER VALLEY BEFORE 12Z. OVERNIGHT MINS WILL BE MUCH MILDER
WITH THE INCREASING CLOUD COVER...AND WILL RANGE FROM THE LOWER
50S IN THE NORTH TO THE MID TO UPPER 50S SOUTHEAST.

&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/...
NO CHANGES TO THE THINKING ON MONDAY AS UPPER LOW OVER THE
SOUTHEAST CONUS WILL LIFT NORTH ALONG THE E COAST. ASSOCIATED
MOIST...EASTERLY LL JET AND UPPER LVL DIVERGENCE PRECEDING THE
UPPER LOW WILL LIKELY BRING SCT SHOWERS TO CENTRAL PA BEGINNING
LATE TONIGHT ACROSS THE SOUTHEAST ZONES AND OVERSPREADING THE
REST OF CENTRAL PA DURING MONDAY. CLOUD COVER...PRECIP AND
EASTERLY FLOW OFF THE ATLANTIC WILL RESULT IN A MUCH COOLER
MONDAY WITH MAX TEMPS ONLY ARND 70F. GEFS DATA SHOWING HIGHEST
PWATS ACROSS SOUTHEAST PA...WHERE THE BEST CHC OF MEASURABLE
RAINFALL IS EXPECTED SUN NITE/MONDAY.

DOWNSLOPING SE FLOW WILL RESULT IN PARTIAL SUNSHINE AND A
SOMEWHAT WARMER MONDAY OVR WARREN COUNTY...WHERE A LATE DAY
TSRA IS POSSIBLE. CAPE VALUES IN THE 600 TO 800JK-1 RANGE
ACROSS WARREN CO MON EVENING. FURTHER EAST...A COOLER MORE
STABLE EASTERLY FLOW SHOULD PRECLUDE THUNDER.

&&

.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
NOT A LOT OF CHANGE FROM THE FCST PACKAGE YESTERDAY.

STILL LOOKS LIKE NORTHERN SYSTEM OFF THE COAST WILL PIVOT AROUND
ALBERTO AND MOVE WESTWARD...BRINGING SHOWERS TO THE AREA ON TUE.
MAIN CHC WILL BE MONDAY INTO TUE.

DID UP TEMPS SOME ON TUE...ALSO SOME CHC OF A THUNDERSTORM WITH
THE WARMER TEMPS.

SHOWERS COULD LINGER INTO WED...ESPECIALLY ACROSS THE SE WITH
THE FRONT.

TRIED TO GO WITH THE MID SHIFT FCST AND HAVE SOME PERIODS OF
DRY WEATHER. HARD TO FIND A LOT OF DRY PERIODS...AS REMAINS OF
CUTOFF COULD KEEP A FEW SHOWERS ACROSS EASTERN AREAS...WHERE
FAR NW AREAS COULD SEE SOME FROM THE COLD FRONT LATE IN THE
WEEK.

WENT WITH A DRY FCST FOR SUNDAY...IT WILL BE CLOSE...HARD TO
SEE THE EAST...WEST COLD FRONT DROPPING TOO FAR SOUTH.

TEMPS WILL BE WARM THROUGHOUT THE PERIOD...ABOVE NORMAL.

&&

.AVIATION /00Z MONDAY THROUGH FRIDAY/...
VFR CONDITIONS PREVAIL ACROSS CENTRAL PENNSYLVANIA. MID CLOUDS
STARTING TO STREAM INTO SOUTHERN TIER COUNTIES NOW...WITH CIGS 050
TO 100.

EASTERLY FLOW WILL PERSIST OVERNIGHT...AND BRING WITH IT A GRADUAL
INCREASE CLOUDS SPREADING IN FROM THE SOUTHWEST. BY 06Z MVFR CIGS
EXPECTED OVER KMDT AND KLNS...AND BY MONDAY MORNING /12Z/ EXPECT
MVFR CIGS TO OVERSPREAD MUCH OF SOUTHEAST PENNSYLVANIA INTO THE
LAURELS. MOISTURE WILL CONTINUE TO INCREASE ACROSS THE REGION ON
SOUTHEAST LOW LEVEL FLOW...AS DEEP LOW LIFTS INTO THE REGION. MVFR
TO IFR CIGS EXPECTED TO OVERSPREAD MOST OF CENTRAL PENNSYLVANIA BY
14-16Z...WITH INCREASING SHOWERS. EXCEPTION MAY BE FAR NW /KBFD/
WHERE VFR CONDITIONS MAY LINGER INTO LATER AFTERNOON.

OUTLOOK...
MON NIGHT-WED...WIDESPREAD MVFR/IFR CIGS AND VSBYS LIKELY IN
SHOWERS AND SCT TSRA.
THU...PRIMARILY VFR. SCT SHRA/TSTM POSS MAINLY SE.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...GRUMM/FITZGERALD
NEAR TERM...DEVOIR
SHORT TERM...DEVOIR
LONG TERM...MARTIN
AVIATION...JUNG/DEVOIR

000
FXUS61 KPBZ 202327
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
727 PM EDT SUN MAY 20 2012

.SYNOPSIS...
BY MONDAY AFTERNOON...THE REGION WILL BE SQUEEZED BY AREAS OF
PRECIPITATION FROM THE WEST AND EAST. THE BEST CHANCE FOR SHOWERS
WILL BE ON TUESDAY. HIGH PRESSURE WILL BRING DRY WEATHER FOR
WEDNESDAY AND THURSDAY.

&&

.NEAR TERM /THROUGH MONDAY/...
UPDATE FOR MINOR ADJUSTMENTS TO SKY COVER. ALTHOUGH TROPICAL STORM
ALBERTO OFF THE COAST OF SOUTH CAROLINA HAS BEEN THE MAIN WEATHER
FOCUS IN THE LAST DAY...AN EXTRATROPICAL STORM OFF THE VIRGINIA
COAST WILL BE ONE OF THE PRIMARY FACTORS IN THE LOCAL FORECAST FOR
THE NEXT 48 HOURS. HIGH PRESSURE RIDGE CURRENTLY OVER THE REGION
WILL BE PUSHED OFF TO THE NORTHEAST OVERNIGHT...WITH THE VIRGINIA
LOW SLOWLY MOVING ONSHORE DURING THAT TIME PERIOD. WITH THE SLOW
PROGRESS...ONLY A SLIGHT CHANCE OF SHOWERS FOR THE RIDGES IS
FORECAST LATE TONIGHT. MEANWHILE...A COLD FRONT CURRENTLY
STRETCHING FROM UPPER MICHIGAN SOUTH INTO MISSOURI WILL MOVE
EAST...MOVING INTO INDIANA BY MONDAY MORNING.

TO THE EAST...LOW PRESSURE WILL SLOWLY DISSIPATE AS IT MOVES INTO
CENTRAL PENNSYLVANIA...THEN VEERS INTO NEW YORK. THIS WILL INCREASE
THE CHANCE OF SHOWERS AND THUNDERSTORMS FROM EAST TO WEST...BUT
LIKELY POPS WILL REMAIN EAST OF US. AT THE SAME TIME...THE COLD
FRONT WILL APPROACH THE WESTERN EDGE OF THE FORECAST AREA BY LATE
MONDAY AFTERNOON. ALTHOUGH INSTABILITY VALUES WILL BE LIGHT TO
MODERATE...WIND PROFILES UP TO 25 KFT ARE NEARLY CALM...WHICH SHOULD
PREVENT ANY CHANCE FOR SEVERE WEATHER. WITH CLOUD COVER
OVERSPREADING EASTERN COUNTIES THE MOST...LOWS WILL BE HELD TO THE
LOW AND MID 70S EAST...WITH MID 80S STILL POSSIBLE WEST.

&&

.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
COLD FRONT WILL CONTINUE TO PROGRESS EAST MONDAY NIGHT...BUT WITH
LITTLE IN THE WAY OF DEEP MOISTURE. WILL CONTINUE CHANCE POPS MONDAY
NIGHT INTO TUESDAY...WITH LIKELY POPS ONLY MENTIONED ACROSS THE
RIDGES TUESDAY AFTERNOON WHERE OROGRAPHIC LIFT SHOULD HELP TO
GENERATE SHOWERS. INSTABILITY STILL LOOKS QUITE LIMITED...AND HAVE
CONTAINED THUNDER MENTION ONLY TO LOCATIONS WITH LIKELY POPS. WITH
WIDESPREAD CLOUD COVER...HIGHS EVERYWHERE WILL DROP BACK TO
SEASONABLE LEVELS.

BY TUESDAY NIGHT...THE UPPER LEVEL TROUGH ASSOCIATED WITH THE COLD
FRONT IS EXPECTED TO CLOSE OFF INTO AN UPPER LOW OVER THE CAROLINAS
AND REMAIN STATIONARY INTO WEDNESDAY. THE CUTOFF FLOW IS EXPECTED TO
KEEP SKIES PARTLY/MOSTLY CLOUDY...WITH A CHANCE OF SHOWERS
CONTINUING TO PERSIST. WITH SOME BREAKS IN CLOUD COVER...HIGHS WILL
RISE A COUPLE OF DEGREES FROM TUESDAY/S VALUES.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
A NEARLY STATIONARY UPPER LEVEL LOW/TROUGH WILL BE NEAR THE
CAROLINAS. HOWEVER...MODEL SOLUTIONS DIFFER. AT THIS TIME ENSEMBLE
TREND IS STILL TO KEEP A DRIER FORECAST FOR THE COUNTY WARNING
AREA...SO WILL CONTINUE THE TREND. THE PERIOD IS PROJECTED TO BE
WARM WITH ABOVE AVERAGE TEMPERATURES APPROACHING 90 DEGREES AND
SFC DEWPOINTS IN THE LOW TO MID 60S FOR THE START OF THE MEMORIAL
DAY WEEKEND.

&&

.AVIATION /23Z SUNDAY THROUGH FRIDAY/...
VFR CONDITIONS WILL PREVAIL ACROSS THE TERMINALS THROUGH TOMORROW
MORNING AS HIGH PRESSURE SHIFTS NORTHEAST OF THE AREA.

LOW PRESSURE WILL PULL ATLANTIC MOISTURE INTO THE AREA FROM THE
SOUTHEAST AND A FRONTAL BOUNDARY WILL APPROACH FROM THE WEST
TOMORROW AFTERNOON. THIS WILL MAKE ISOLATED SHOWERS AND
THUNDERSTORMS WITH MVFR RESTRICTIONS POSSIBLE ACROSS THE TERMINALS
LATE TOMORROW AFTERNOON INTO THE EVENING. WITH ISOLATED COVERAGE,
-TSRA IS NOT MENTIONED IN THE TAFS AT THIS POINT. NEAR CALM WINDS
OVERNIGHT WILL BECOME SOUTHEASTERLY AT AROUND 5KTS TOMORROW.

.OUTLOOK...MONDAY NIGHT THROUGH FRIDAY...
MOISTURE WILL INCREASE FROM THE EAST AS LOW PRESSURE MOVES UP THE
EASTERN SEABOARD. AN INCREASE IN LOW LEVEL MOISTURE MAY SET OFF
ISOLATED SHOWERS AND THUNDERSTORMS WITH RESTRICTIONS MONDAY NIGHT
THROUGH WEDNESDAY. SFC DEWPOINTS WILL INCREASE THROUGH THE PERIOD
AND WILL RESULT IN VISIBILITY RESTRICTIONS DUE TO HZ/BR AT MOST
AIRPORT LOCATIONS DURING THE EARLY MORNING HOURS WEDNESDAY AND
THURSDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$

000
FXUS61 KPHI 202247
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
647 PM EDT SUN MAY 20 2012

.SYNOPSIS...
AN AREA OF LOW PRESSURE WILL MOVE INTO THE MID ATLANTIC REGION FROM
THE EAST TONIGHT, THEN DISSIPATE MONDAY. DURING THE EARLY PART OF
THE WEEK, LOW PRESSURE SHOULD LIFT NORTHEASTWARD FROM THE BAHAMAS
FOLLOWED BY TROPICAL STORM ALBERTO. BOTH SYSTEMS ARE EXPECTED TO
REMAIN WELL TO OUR EAST. A SLOW MOVING FRONTAL BOUNDARY IS FORECAST
TO APPROACH FROM THE WEST TUESDAY AND IT WILL INFLUENCE OUR WEATHER
DURING THE MID WEEK PERIOD BEFORE DISSIPATING. HIGH PRESSURE IS
ANTICIPATED TO BUILD INTO OUR REGION FOR FRIDAY AND SATURDAY. A COLD
FRONT FROM THE NORTH MAY ARRIVE SUNDAY.

&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
AN AREA OF LOW PRESSURE WILL CONTINUE TO SLIDE WESTWARD AND MOVE
INTO VIRGINIA THROUGH TONIGHT. THE FLOW AROUND THIS LOW ALONG
WITH HIGH PRESSURE SITUATED TO OUR NORTHEAST WILL MAINTAIN AN
ONSHORE COMPONENT. THE OVERALL FLOW IS FORECAST TO WEAKEN SOME AS
THE GRADIENT SUBSIDES DUE TO THE LOW WEAKENING. HOWEVER, A PLUME OF
MOISTURE WILL ADVECT INTO THE AREA WITH THE MODEL GUIDANCE
INDICATING THE PW VALUES INCREASING TO NEAR 1.5 INCHES OVERNIGHT.
THERE APPEARS TO BE AN IMPULSE ROTATING AROUND THE SURFACE LOW AND
THIS LOOKS TO BE WHAT THE MAJORITY OF THE MODELS ARE KEYING IN ON.
THIS RESULTS IN SHOWERS THAT EXPAND FROM SOUTHEAST TO NORTHWEST
ACROSS A GOOD PART OF THE CWA DURING THE NIGHT. THIS AREA LOOKS TO
BE THE SHOWERS THAT ARE MOVING ONTO THE ATLANTIC COASTS OF DELAWARE
AND MARYLAND AS OF 2230Z. THE OVERALL TIMING ON THIS HAS SOME LOWER
CONFIDENCE, HOWEVER GIVEN THE INCREASING MOISTURE SOME LOCAL
DOWNPOURS WILL BE POSSIBLE ESPECIALLY OVERNIGHT. AS A RESULT, THE
POPS INCREASE FROM SOUTHEAST TO NORTHWEST DURING THE COURSE OF THE
NIGHT.

THE MOISTENING ONSHORE FLOW WILL ALSO RESULT IN LOW CLOUDS SPREADING
INLAND THROUGH THE NIGHT. THE DAYTIME HEATING AND ENOUGH DRY
LOW-LEVEL AIR HAS BEEN FIGHTING THE MOISTURE SURGE INLAND THUS FAR.
THIS HAS RESULTED IN THE CLOUDS THINNING SOME AS THEY MOVED INLAND.
THIS SHOULD CEASE ONCE THE DAYTIME HEATING IS DONE AND THE BOUNDARY
LAYER CONTINUES TO COOL. THEREFORE, CLOUDS WILL INCREASE AND LOWER
FROM EAST TO WEST. WHILE THERE COULD BE SOME FOG WITH THE LOW LEVELS
MOISTENING UP, THINK MOST OF THE VISIBILITY REDUCTIONS WILL BE TIED
TO THE SHOWERS. THERE IS NOT A LOT OF INSTABILITY FORECAST TO OCCUR,
THEREFORE JUST A CHC OF THUNDER WAS MENTIONED ACROSS PORTIONS OF THE
SOUTHEASTERN CWA FOR AWHILE TONIGHT GIVEN SOME CONVECTION TIED
CLOSER TO THE SURFACE LOW CENTER ATTM.

THE HOURLY GRIDS WERE ADJUSTED TO REFLECT THE FASTER COOLING ACROSS
THE EASTERN ZONES DUE TO THE MARINE INFLUENCE. THE LAMP/LAV GUIDANCE
WAS USED TO ASSIST WITH THIS. THE DEW POINTS ARE ALSO COMING UP AS
THE MOISTURE SURGE BEGINS. THE MUCH LOWER DEW POINTS SITTING ACROSS
NORTHEASTERN PENNSYLVANIA AND NORTHWESTERN NEW JERSEY ARE
ANTICIPATED TO INCREASE THROUGH THE EVENING.

&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/...
MDL SOLNS DIFFER A BIT ON PRECIP TOMORROW. WE WILL STILL BE
IMPACTED BY THE AFOREMENTIONED LOW, BUT IT WILL NOT BE A
COMPLETELY RAINY DAY BY ANY MEANS. THERE WILL BE SHOWERS
AS PIECES OF ENERGY ROTATE AROUND THE LOW. AS A RESULT, THE MDLS
ARE HAVING THEIR DIFFS DETERMINING WHICH PDS WILL BE WET AND WHICH
ONES WILL BE DRY. THERE ARE SOME INDICATIONS THAT THE MORNING
COULD BE WETTER THAN THE AFTN, OVERALL. QPF SHOULD BE 0.50 INCHES
OR LESS.

&&

.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
THE EFFECTS OF TROPICAL STORM ALBERTO SHOULD REMAIN TO OUR EAST
AND WILL LIKELY NOT INFLUENCE OUR LAND AREAS. NEVERTHELESS, THE
WEATHER IS GOING TO BE RATHER UNSETTLED FROM MONDAY NIGHT INTO
THURSDAY. THERE WILL BE A RELATIVELY LIGHT FLOW NEAR THE SURFACE
AS WELL AS IN THE MID AND UPPER LEVELS OF THE ATMOSPHERE DURING
MUCH OF THE PERIOD. A FAIR AMOUNT OF LOW LEVEL MOISTURE SHOULD
LINGER IN OUR REGION. AS A RESULT, CLOUDS AND SCATTERED SHOWERS
ARE ANTICIPATED.

A SLOW MOVING BOUNDARY FROM THE WEST SHOULD BEGIN TO APPROACH
FROM THE WEST ON TUESDAY BEFORE MOVING INTO OUR VICINITY FOR
TUESDAY NIGHT AND WEDNESDAY. THE FRONT IS EXPECTED TO DISSIPATE
GRADUALLY.

WITH DAYTIME HEATING, THERE WILL BE AN INCREASE IN INSTABILITY
DURING THE AFTERNOON AND EVENING HOURS ON TUESDAY AND WEDNESDAY,
ESPECIALLY AT LOCATIONS A BIT REMOVED FROM THE OCEAN INFLUENCE. AS
A RESULT, WE WILL INDICATE AT CHANCE OF AFTERNOON AND EVENING
THUNDERSTORMS ON BOTH DAYS, EXCEPT NEAR THE COAST.

WITH THE REMNANTS OF THE BOUNDARY IN OR NEAR OR REGION ON
THURSDAY AND WITH A MID LEVEL TROUGH OR LOW PASSING NEARBY OR
OVERHEAD, WE WILL AGAIN CARRY A CHANCE OF SHOWERS AND
THUNDERSTORMS.

DUE TO THE LIGHT ATMOSPHERIC FLOW, ANY SHOWERS AND THUNDERSTORMS
ON TUESDAY, WEDNESDAY AND THURSDAY MAY BE SLOW MOVING AND THEY
COULD LEAVE MODERATE TO HEAVY RAINFALL AT SOME LOCATIONS.

HIGH PRESSURE IS EXPECTED TO PUSH INTO OUR REGION FROM THE
NORTHEAST FOR FRIDAY AND SATURDAY WITH A TREND TOWARD DRY WEATHER
ANTICIPATED. A FRONTAL BOUNDARY FROM THE NORTHWEST MAY ARRIVE ON
SATURDAY NIGHT OR SUNDAY.

TEMPERATURES SHOULD BE NEAR OR SLIGHTLY ABOVE NORMAL FOR THIS
TIME OF THE YEAR FROM MONDAY NIGHT THROUGH THURSDAY NIGHT. WITH
DRY AIR BUILDING INTO OUR REGION, ABOVE NORMAL TEMPERATURES ARE
EXPECTED FOR FRIDAY INTO THE WEEKEND, EVEN WITH THE ARRIVAL OF THE
FRONTAL BOUNDARY FROM THE NORTHWEST.

&&

.AVIATION /00Z MONDAY THROUGH FRIDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.

THE AIRMASS WILL CONTINUE TO MOISTEN FROM EAST TO WEST TONIGHT,
THEREFORE THE LOWER CLOUDS THAT CONTINUE IN THE KMIV AND KACY AREAS
WILL MIGRATE INLAND. THE MAIN FORECAST CHALLENGES ARE HOW QUICKLY
THIS OCCURS AND HOW LOW THE CEILINGS END UP GETTING. THE HEATING
INLAND HAS ALLOWED THE CLOUD BASES TO RISE AND EVEN THIN LATE THIS
AFTERNOON ACROSS MOST OF INTERIOR NEW JERSEY, DELAWARE AND FAR
SOUTHEASTERN PENNSYLVANIA. ONCE THE HEATING IS LOST AND THE LOWER
LEVELS COOL, THE MOISTURE SURGE SHOULD BE ABLE TO MOVE INLAND MORE
EFFICIENTLY. AS A RESULT, WE ARE EXPECTING THE CEILINGS TO INCREASE
AND LOWER THROUGH THE NIGHT FROM EAST TO WEST. WE BROUGHT ALL OF OUR
TERMINALS DOWN TO MVFR DURING THE NIGHT THEN EVEN TO IFR LATE, WITH
THIS ALREADY HAPPENING OR WILL OCCUR MUCH FASTER AT KMIV AND
KACY.

THERE WILL BE SHOWERS DEVELOPING AS WELL GENERALLY FROM SOUTHEAST TO
NORTHWEST DURING THE COURSE OF THE NIGHT. THERE IS LOWER CONFIDENCE
ON THE TIMING AND COVERAGE OF THESE, HOWEVER GIVEN THE DEEPENING
MOISTURE THROUGH THE NIGHT, LOCAL DOWNPOURS WILL BE POSSIBLE. THE
MAIN SHOWERS LOOK TO BE WHAT IS MOVING ONSHORE OF DELAWARE AND
MARYLAND AS OF 2230Z. THE THUNDER CHANCES SEEM TO BE RATHER LOW,
THEREFORE NO MENTION WAS INCLUDED AT THIS TIME. THE NORTHEAST TO
EAST WINDS WILL SETTLE THROUGH THE NIGHT GENERALLY TO ABOUT 10
KNOTS, AS THE PRESSURE GRADIENT WEAKENS SOME DUE TO THE LOW PRESSURE
SYSTEM TO OUR SOUTH WEAKENING.

FOR MONDAY, SUB-VFR CONDITIONS ARE EXPECTED TO CONTINUE AS A
WEAKNESS IN THE ATMOSPHERE REMAINS IN PLACE ALONG WITH AN ABUNDANCE
OF MOISTURE. THERE SHOULD BE LOWER CLOUDS AND PERHAPS A TOUCH OF FOG
IN THE MORNING ALONG WITH SHOWERS, THE THERE MAY BE A LULL IN THE
SHOWERS FOR AWHILE. AGAIN, THERE IS LOWER CONFIDENCE REGARDING
THE TIMING AND COVERAGE OF THE SHOWERS. WHILE SOME THUNDERSTORMS ARE
POSSIBLE, THEY DO NOT APPEAR TO BE ALL THAT WIDESPREAD, THEREFORE
THIS WAS NOT INCLUDED AT THIS TIME. THE WINDS WILL GENERALLY BE FROM
THE EAST AROUND 10 KNOTS.

OUTLOOK...
MONDAY NIGHT THROUGH THURSDAY...MVFR/IFR CEILING AND VISIBILITY
VALUES ARE POSSIBLE, ALONG WITH SCATTERED SHOWERS, DURING THE
OVERNIGHT AND MORNING HOURS EACH DAY. MAINLY VFR CONDITIONS ARE
EXPECTED DURING THE AFTERNOON AND EVENING HOURS, EXCEPT IN
SCATTERED SHOWERS AND THUNDERSTORMS. THE WIND SHOULD BE MAINLY 10
KNOTS OR LESS AND IT MAY FAVOR THE EAST TO SOUTH QUADRANT.

THURSDAY NIGHT AND FRIDAY...MAINLY VFR WITH A SOUTH WIND 10 KNOTS
OR LESS. SOME LATE NIGHT AND EARLY MORNING VISIBILITY RESTRICTIONS
ARE POSSIBLE.

&&

.MARINE...
THE SMALL CRAFT ADVISORY FOR UPPER DELAWARE BAY HAS BEEN CANCELLED.
THE PRESSURE GRADIENT IS FORECAST TO RELAX SOME THROUGH THE NIGHT AS
LOW PRESSURE MOVES INLAND AND ALSO BEGINS TO WEAKEN. THE WINDS HAVE
NOT BEEN REACHING CRITERIA ACROSS THE UPPER BAY AND THEY SHOULD NOT
INCREASE TO THESE LEVELS TONIGHT. THE WINDS ACROSS LOWER DELAWARE
BAY ARE STRONGER, WITH THE STRONGEST GUSTS MAINLY NEAR THE LEWES
AREA DUE TO THE NORTHEAST FETCH. WE WILL KEEP THE ADVISORY HERE FOR
NOW DUE TO GUSTS TO ABOUT 25 KNOTS NEAR THE MOUTH OF THE BAY.

PROLONGED NORTHEAST TO EAST FLOW IS EXPECTED THROUGH MONDAY AS LOW
PRESSURE WEAKENS ACROSS THE MID ATLANTIC. SEAS WILL REMAIN AT OR
ABOVE 5 FEET WITH THE HIGHER SETS ACROSS THE SOUTHERN WATERS DUE TO
A LONGER FETCH AND INITIALLY STRONGER WINDS. THE SMALL CRAFT ADVISORY
REMAINS IN EFFECT AS A RESULT THROUGH MONDAY. THE WINDS WILL GUST
THROUGH THIS EVENING, ESPECIALLY ACROSS THE SOUTHERN WATERS, THEN
TEND TO DIMINISH SOME LATER TONIGHT AS THE PRESSURE GRADIENT BEGINS
TO RELAX SOME.

OUTLOOK...
WIND SPEEDS ARE FORECAST TO REMAIN BELOW THE SMALL CRAFT ADVISORY
CRITERION FOR THE PERIOD FROM MONDAY NIGHT THROUGH FRIDAY.

WAVE HEIGHTS ON OUR OCEAN WATERS ARE EXPECTED TO REMAIN AT 5 FEET
OR GREATER INTO THE MID WEEK PERIOD, AS TROPICAL STORM ALBERTO
PASSES WELL TO OUR EAST. FOR NOW, THE SMALL CRAFT ADVISORY ON OUR
OCEAN WATERS HAS BEEN EXTENDED UNTIL 600 AM TUESDAY.

&&

.TIDES/COASTAL FLOODING...
IT STILL APPEARS THAT MOST, IF NOT ALL SITES, WILL REMAIN BELOW
MINOR TIDAL FLOODING CRITERIA THROUGH MONDAY /AND BEYOND/. THE BEST
CHANCE FOR REACHING THE THRESHOLD WOULD BE OVER OUR FAR SOUTHERN
COASTAL AREAS DUE TO A STRONGER ONSHORE FLOW AND HIGHER SEAS.

&&

.RIP CURRENTS...
THE RISK OF RIP CURRENTS IN THE HIGH CATEGORY REMAINS IN EFFECT
THROUGH LATER THIS EVENING.

WHILE THE ONSHORE FLOW WILL PERSIST MONDAY, IT IS FORECAST TO NOT BE
AS STRONG AS SUNDAY. IN ADDITION, THE SEAS ARE FORECAST TO BE
SOMEWHAT LOWER. BASED ON THIS, WE CAME UP WITH A MODERATE RISK OF
RIP CURRENTS FOR MONDAY.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...HIGH RIP CURRENT RISK UNTIL 11 PM EDT THIS EVENING FOR NJZ014-
     024>026.
DE...HIGH RIP CURRENT RISK UNTIL 11 PM EDT THIS EVENING FOR DEZ004.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT TUESDAY FOR ANZ452>455.
     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 AM EDT TUESDAY
     FOR ANZ450-451.
     SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR ANZ431.

&&

$$
SYNOPSIS...GORSE/IOVINO
NEAR TERM...GORSE
SHORT TERM...NIERENBERG
LONG TERM...IOVINO
AVIATION...GORSE/IOVINO
MARINE...GORSE/IOVINO
TIDES/COASTAL FLOODING...NIERENBERG
RIP CURRENTS...GORSE

000
FXUS61 KPBZ 202215
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
615 PM EDT SUN MAY 20 2012

.SYNOPSIS...
BY MONDAY AFTERNOON...THE REGION WILL BE SQUEEZED BY AREAS OF
PRECIPITATION FROM THE WEST AND EAST. THE BEST CHANCE FOR SHOWERS
WILL BE ON TUESDAY. HIGH PRESSURE WILL BRING DRY WEATHER FOR
WEDNESDAY AND THURSDAY.

&&

.NEAR TERM /THROUGH MONDAY/...
UPDATE FOR MINOR ADJUSTMENTS TO SKY COVER. ALTHOUGH TROPICAL STORM
ALBERTO OFF THE COAST OF SOUTH CAROLINA HAS BEEN THE MAIN WEATHER
FOCUS IN THE LAST DAY...AN EXTRATROPICAL STORM OFF THE VIRGINIA
COAST WILL BE ONE OF THE PRIMARY FACTORS IN THE LOCAL FORECAST FOR
THE NEXT 48 HOURS. HIGH PRESSURE RIDGE CURRENTLY OVER THE REGION
WILL BE PUSHED OFF TO THE NORTHEAST OVERNIGHT...WITH THE VIRGINIA
LOW SLOWLY MOVING ONSHORE DURING THAT TIME PERIOD. WITH THE SLOW
PROGRESS...ONLY A SLIGHT CHANCE OF SHOWERS FOR THE RIDGES IS
FORECAST LATE TONIGHT. MEANWHILE...A COLD FRONT CURRENTLY
STRETCHING FROM UPPER MICHIGAN SOUTH INTO MISSOURI WILL MOVE
EAST...MOVING INTO INDIANA BY MONDAY MORNING.

TO THE EAST...LOW PRESSURE WILL SLOWLY DISSIPATE AS IT MOVES INTO
CENTRAL PENNSYLVANIA...THEN VEERS INTO NEW YORK. THIS WILL INCREASE
THE CHANCE OF SHOWERS AND THUNDERSTORMS FROM EAST TO WEST...BUT
LIKELY POPS WILL REMAIN EAST OF US. AT THE SAME TIME...THE COLD
FRONT WILL APPROACH THE WESTERN EDGE OF THE FORECAST AREA BY LATE
MONDAY AFTERNOON. ALTHOUGH INSTABILITY VALUES WILL BE LIGHT TO
MODERATE...WIND PROFILES UP TO 25 KFT ARE NEARLY CALM...WHICH SHOULD
PREVENT ANY CHANCE FOR SEVERE WEATHER. WITH CLOUD COVER
OVERSPREADING EASTERN COUNTIES THE MOST...LOWS WILL BE HELD TO THE
LOW AND MID 70S EAST...WITH MID 80S STILL POSSIBLE WEST.

&&

.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
COLD FRONT WILL CONTINUE TO PROGRESS EAST MONDAY NIGHT...BUT WITH
LITTLE IN THE WAY OF DEEP MOISTURE. WILL CONTINUE CHANCE POPS MONDAY
NIGHT INTO TUESDAY...WITH LIKELY POPS ONLY MENTIONED ACROSS THE
RIDGES TUESDAY AFTERNOON WHERE OROGRAPHIC LIFT SHOULD HELP TO
GENERATE SHOWERS. INSTABILITY STILL LOOKS QUITE LIMITED...AND HAVE
CONTAINED THUNDER MENTION ONLY TO LOCATIONS WITH LIKELY POPS. WITH
WIDESPREAD CLOUD COVER...HIGHS EVERYWHERE WILL DROP BACK TO
SEASONABLE LEVELS.

BY TUESDAY NIGHT...THE UPPER LEVEL TROUGH ASSOCIATED WITH THE COLD
FRONT IS EXPECTED TO CLOSE OFF INTO AN UPPER LOW OVER THE CAROLINAS
AND REMAIN STATIONARY INTO WEDNESDAY. THE CUTOFF FLOW IS EXPECTED TO
KEEP SKIES PARTLY/MOSTLY CLOUDY...WITH A CHANCE OF SHOWERS
CONTINUING TO PERSIST. WITH SOME BREAKS IN CLOUD COVER...HIGHS WILL
RISE A COUPLE OF DEGREES FROM TUESDAY/S VALUES.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
A NEARLY STATIONARY UPPER LEVEL LOW/TROUGH WILL BE NEAR THE
CAROLINAS. HOWEVER...MODEL SOLUTIONS DIFFER. AT THIS TIME ENSEMBLE
TREND IS STILL TO KEEP A DRIER FORECAST FOR THE COUNTY WARNING
AREA...SO WILL CONTINUE THE TREND. THE PERIOD IS PROJECTED TO BE
WARM WITH ABOVE AVERAGE TEMPERATURES APPROACHING 90 DEGREES AND
SFC DEWPOINTS IN THE LOW TO MID 60S FOR THE START OF THE MEMORIAL
DAY WEEKEND.

&&

.AVIATION /22Z SUNDAY THROUGH FRIDAY/...
THERE WILL BE MOSTLY CLEAR SKIES AND LIGHT WINDS THROUGH MONDAY
MORNING. SOME EARLY MORNING VISIBILITY RESTRICTIONS EXPECTED
ACROSS EASTERN OH IN THE KZZV AREA TO AROUND 5 MILES DUE TO HZ/BR.
MID CLOUDS DECK WILL WORK INTO THE AREA MONDAY.

.OUTLOOK...MONDAY NIGHT THROUGH FRIDAY...
MOISTURE INCREASES FROM THE EAST AS LOW PRESSURE MOVES UP THE
EASTERN SEABOARD. INCREASE IN LOW LEVEL MOISTURE MAY SET OFF
ISOLATED TRW- LATE MONDAY THROUGH WEDNESDAY WITH MVFR
RESTRICTIONS IN AND NEAR TRW-. SFC DEWPOINTS INCREASE THROUGH THE
PERIOD AND WILL RESULT IN VISIBILITY RESTRICTIONS DUE TO HZ/BR AT
MOST AIRPORT LOCATIONS DURING EARLY MORNING HOURS WEDNESDAY AND
THURSDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$

000
FXUS61 KCTP 202134
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
534 PM EDT SUN MAY 20 2012

.SYNOPSIS...
HIGH PRESSURE WILL PUSH WELL OFF THE COASTAL NEW ENGLAND WATERS
TONIGHT. AN INCREASING MOIST EAST TO SOUTHEAST FLOW WILL PUSH
ATLANTIC MOISTURE INTO CENTRAL PENNSYLVANIA LATE TONIGHT AND
MONDAY...AS AN UPPER LEVEL TROF MOVES TO THE CENTRAL GREAT LAKES
ON MONDAY. THIS WILL BRING AN INCREASING CHANCE OF SHOWERS TO ALL
OF CENTRAL PA ON MONDAY. AN UPPER LEVEL LOW OVER THE SOUTHEAST
WILL SLOWLY TRACK NORTHEASTWARD THROUGH MID WEEK...KEEPING
UNSETTLED WEATHER ALONG THE EASTERN SEABOARD...AND A DAILY CHANCE
OF SHOWERS AND THUNDERSTORMS OVER CENTRAL PENNSYLVANIA.
PENNSYLVANIA WILL BE ON THE EDGE OF A BUILDING A LARGE UPPER HIGH
ACROSS THE TENNESSEE RIVER VALLEY AND SOUTHEASTERN STATES BY THE
END OF THIS WEEK.

&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
LLVL MOISTURE PUSHING WESTWARD INTO NRN MD FROM DE AND SOUTHERN
NEW JERSEY THIS AFTERNOON AS DEEPER LLVL ELY FLOW CONTS TO DRAW
ATLANTIC MOISTURE INLAND. CLEAR SKIES SHOULD PREVAIL FOR MOST OF
CENTRAL PA THIS EVENING...WITH LOW CLOUDS APPROACHING LATER THIS
EVENING ACROSS LANCASTER AND YORK COUNTIES. AFTER SUNSET...CLOUDS
WILL CONTINUE THEIR TREK WESTWARD AND NORTHWARD...EVENTUALLY
OVERSPREADING MOST IF NOT ALL OF CENTRAL BY BY 12Z MON. FAR
NORTHWEST AREAS MAY ESCAPE BKN CIGS. ALL BUT THE LOWER SUSQ. SHOULD
REMAIN DRY TONIGHT...BUT AREAS OF DRIZZLE AND LIGHT SHOWERS ARE
CERTAINLY POSSIBLE IN THE DEEPER MARITIME AIR MASS OVER THE LOWER
SUSQ RIVER VALLEY BEFORE 12Z. OVERNIGHT MINS WILL BE MUCH MILDER
WITH THE INCREASING CLOUD COVER...AND WILL RANGE FROM THE LOWER
50S IN THE NORTH TO THE MID TO UPPER 50S SOUTHEAST.

&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/...
NO CHANGES TO THE THINKING ON MONDAY AS UPPER LOW OVER THE
SOUTHEAST CONUS WILL LIFT NORTH ALONG THE E COAST. ASSOCIATED
MOIST...EASTERLY LL JET AND UPPER LVL DIVERGENCE PRECEDING THE
UPPER LOW WILL LIKELY BRING SCT SHOWERS TO CENTRAL PA BEGINNING
LATE TONIGHT ACROSS THE SOUTHEAST ZONES AND OVERSPREADING THE
REST OF CENTRAL PA DURING MONDAY. CLOUD COVER...PRECIP AND
EASTERLY FLOW OFF THE ATLANTIC WILL RESULT IN A MUCH COOLER
MONDAY WITH MAX TEMPS ONLY ARND 70F. GEFS DATA SHOWING HIGHEST
PWATS ACROSS SOUTHEAST PA...WHERE THE BEST CHC OF MEASURABLE
RAINFALL IS EXPECTED SUN NITE/MONDAY.

DOWNSLOPING SE FLOW WILL RESULT IN PARTIAL SUNSHINE AND A
SOMEWHAT WARMER MONDAY OVR WARREN COUNTY...WHERE A LATE DAY
TSRA IS POSSIBLE. CAPE VALUES IN THE 600 TO 800JK-1 RANGE
ACROSS WARREN CO MON EVENING. FURTHER EAST...A COOLER MORE
STABLE EASTERLY FLOW SHOULD PRECLUDE THUNDER.

&&

.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
NOT A LOT OF CHANGE FROM THE FCST PACKAGE YESTERDAY.

STILL LOOKS LIKE NORTHERN SYSTEM OFF THE COAST WILL PIVOT AROUND
ALBERTO AND MOVE WESTWARD...BRINGING SHOWERS TO THE AREA ON TUE.
MAIN CHC WILL BE MONDAY INTO TUE.

DID UP TEMPS SOME ON TUE...ALSO SOME CHC OF A THUNDERSTORM WITH
THE WARMER TEMPS.

SHOWERS COULD LINGER INTO WED...ESPECIALLY ACROSS THE SE WITH
THE FRONT.

TRIED TO GO WITH THE MID SHIFT FCST AND HAVE SOME PERIODS OF
DRY WEATHER. HARD TO FIND A LOT OF DRY PERIODS...AS REMAINS OF
CUTOFF COULD KEEP A FEW SHOWERS ACROSS EASTERN AREAS...WHERE
FAR NW AREAS COULD SEE SOME FROM THE COLD FRONT LATE IN THE
WEEK.

WENT WITH A DRY FCST FOR SUNDAY...IT WILL BE CLOSE...HARD TO
SEE THE EAST...WEST COLD FRONT DROPPING TOO FAR SOUTH.

TEMPS WILL BE WARM THROUGHOUT THE PERIOD...ABOVE NORMAL.

&&

.AVIATION /22Z SUNDAY THROUGH FRIDAY/...
VFR CONDITIONS PREVAIL ACROSS CENTRAL PENNSYLVANIA...WITH ONLY THE
FIRST HINTS OF SOME HIGH CLOUDS STARTING TO SPREAD INTO FAR
SOUTHWEST COUNTIES.

EASTERLY FLOW WILL PERSIST OVERNIGHT...AND BRING WITH IT A GRADUAL
INCREASE CLOUDS SPREADING IN FROM THE SOUTHWEST. BY MONDAY
MORNING...EXPECT MVFR CIGS TO OVERSPREAD MUCH OF SOUTHEAST
PENNSYLVANIA INTO THE LAURELS. MOISTURE WILL CONTINUE TO INCREASE
ACROSS THE REGION ON SOUTHEAST LOW LEVEL FLOW...AS DEEP LOW LIFTS
INTO THE REGION. MVFR TO IFR CIGS EXPECTED TO OVERSPREAD MOST OF
CENTRAL PENNSYLVANIA BY MID DAY...WITH INCREASING SHOWERS.

OUTLOOK...
MON NIGHT-WED...WIDESPREAD MVFR/IFR CIGS AND VSBYS LIKELY IN
SHOWERS AND SCT TSRA.
THU...PRIMARILY VFR. SCT SHRA/TSTM POSS MAINLY SE.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...GRUMM/FITZGERALD
NEAR TERM...DEVOIR
SHORT TERM...DEVOIR
LONG TERM...MARTIN
AVIATION...JUNG/DEVOIR

000
FXUS61 KPHI 201928
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
328 PM EDT SUN MAY 20 2012

.SYNOPSIS...
HIGH PRESSURE REMAINED OVER THE NORTHEASTERN STATES THIS
AFTERNOON WITH LOW PRESSURE CENTERED ABOUT 100 MILES EAST OF THE
VIRGINIA CAPES. THE LOW IS FORECAST TO DRIFT WESTWARD, REACHING
THE COAST THIS EVENING, THEN IT SHOULD DISSIPATE ON MONDAY. DURING
THE EARLY PART OF THE NEW WEEK, LOW PRESSURE SHOULD LIFT
NORTHEASTWARD FROM THE BAHAMAS FOLLOWED BY TROPICAL STORM ALBERTO.
BOTH SYSTEMS ARE EXPECTED TO REMAIN WELL TO OUR EAST. A SLOW
MOVING FRONTAL BOUNDARY IS FORECAST TO APPROACH FROM THE WEST ON
TUESDAY AND IT WILL LIKELY INFLUENCE OUR REGION DURING THE MID
WEEK PERIOD BEFORE DISSIPATING. HIGH PRESSURE IS ANTICIPATED TO
BUILD INTO OUR REGION FROM THE NORTHEAST FOR FRIDAY AND SATURDAY.
A COLD FRONT FROM THE NORTH MAY ARRIVE ON SUNDAY.

&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
LATEST SATELLITE IMAGERY IS NICELY DEPICTING THE SWIRL ASSOCIATED
WITH THE AREA OF LOW PRESSURE OFF THE DELMARVA COAST. THIS LOW IS
FCST TO SLOWLY MOVE WWD TONIGHT. LOW CLOUDINESS ASSOCD WITH THIS
LOW HAS BEEN MOVG ACRS S JERSEY ALL DAY AND WILL IMPACT MORE OF
THE AREA TONIGHT. EXPECT RAIN TO DEVELOP LATER TONIGHT AS WELL.

MDL GUID IS IN GOOD AGREEMENT WRT TEMPS AND WAS GENLY FOLLOWED.

&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/...
MDL SOLNS DIFFER A BIT ON PRECIP TOMORROW. WE WILL STILL BE
IMPACTED BY THE AFOREMENTIONED LOW, BUT IT WILL NOT BE A
COMPLETELY RAINY DAY BY ANY MEANS. THERE WILL BE PERIODS OF RAIN
AS PIECES OF ENERGY ROTATE AROUND THE LOW. AS A RESULT, THE MDLS
ARE HAVING THEIR DIFFS DETERMINING WHICH PDS WILL BE WET AND WHICH
ONES WILL BE DRY. THERE ARE SOME INDICATIONS THAT THE MORNING
COULD BE WETTER THAN THE AFTN, OVERALL. QPF SHOULD BE 0.50 INCHES
OR LESS.

&&

.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
THE EFFECTS OF TROPICAL STORM ALBERTO SHOULD REMAIN TO OUR EAST
AND WILL LIKELY NOT INFLUENCE OUR LAND AREAS. NEVERTHELESS, THE
WEATHER IS GOING TO BE RATHER UNSETTLED FROM MONDAY NIGHT INTO
THURSDAY. THERE WILL BE A RELATIVELY LIGHT FLOW NEAR THE SURFACE
AS WELL AS IN THE MID AND UPPER LEVELS OF THE ATMOSPHERE DURING
MUCH OF THE PERIOD. A FAIR AMOUNT OF LOW LEVEL MOISTURE SHOULD
LINGER IN OUR REGION. AS A RESULT, CLOUDS AND SCATTERED SHOWERS
ARE ANTICIPATED.

A SLOW MOVING BOUNDARY FROM THE WEST SHOULD BEGIN TO APPROACH
FROM THE WEST ON TUESDAY BEFORE MOVING INTO OUR VICINITY FOR
TUESDAY NIGHT AND WEDNESDAY. THE FRONT IS EXPECTED TO DISSIPATE
GRADUALLY.

WITH DAYTIME HEATING, THERE WILL BE AN INCREASE IN INSTABILITY
DURING THE AFTERNOON AND EVENING HOURS ON TUESDAY AND WEDNESDAY,
ESPECIALLY AT LOCATIONS A BIT REMOVED FROM THE OCEAN INFLUENCE. AS
A RESULT, WE WILL INDICATE AT CHANCE OF AFTERNOON AND EVENING
THUNDERSTORMS ON BOTH DAYS, EXCEPT NEAR THE COAST.

WITH THE REMNANTS OF THE BOUNDARY IN OR NEAR OR REGION ON
THURSDAY AND WITH A MID LEVEL TROUGH OR LOW PASSING NEARBY OR
OVERHEAD, WE WILL AGAIN CARRY A CHANCE OF SHOWERS AND
THUNDERSTORMS.

DUE TO THE LIGHT ATMOSPHERIC FLOW, ANY SHOWERS AND THUNDERSTORMS
ON TUESDAY, WEDNESDAY AND THURSDAY MAY BE SLOW MOVING AND THEY
COULD LEAVE MODERATE TO HEAVY RAINFALL AT SOME LOCATIONS.

HIGH PRESSURE IS EXPECTED TO PUSH INTO OUR REGION FROM THE
NORTHEAST FOR FRIDAY AND SATURDAY WITH A TREND TOWARD DRY WEATHER
ANTICIPATED. A FRONTAL BOUNDARY FROM THE NORTHWEST MAY ARRIVE ON
SATURDAY NIGHT OR SUNDAY.

TEMPERATURES SHOULD BE NEAR OR SLIGHTLY ABOVE NORMAL FOR THIS
TIME OF THE YEAR FROM MONDAY NIGHT THROUGH THURSDAY NIGHT. WITH
DRY AIR BUILDING INTO OUR REGION, ABOVE NORMAL TEMPERATURES ARE
EXPECTED FOR FRIDAY INTO THE WEEKEND, EVEN WITH THE ARRIVAL OF THE
FRONTAL BOUNDARY FROM THE NORTHWEST.

&&

.AVIATION /20Z SUNDAY THROUGH FRIDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.

WITH THE EXCEPTION OF KMIV AND KACY, ALL TAF SITES ARE VFR. KMIV
AND KACY ARE MVFR DUE TO LOW CLOUDS MOVG WWD FROM AN AREA OF LOW
PRESSURE OFF THE DELMARVA CST.

EXPECT CLOUDS TO LOWER AND THICKEN EVERYWHERE THIS EVENING AND
TONIGHT AND MVFR CONDS AND EVENTUALLY IFR CONDS WILL BECOME
PREVALENT. ALSO, LATER TONIGHT, SHOWERS WILL DEVELOP AS WELL.

THE LOW PRESSURE WILL MOVE WWD THRU MONDAY AND KEEP THINGS RATHER
UNSETTLED. WHILE THERE WILL BE WET AND DRY PDS, EXPECT MAINLY MVFR
(OR LOWER) DURG THIS TIME.

THE WIND WILL GENLY BE FROM THE NE BECOMING MORE ELY TONIGHT AND
MONDAY WITH SPEEDS AROUND 10 KT. THE GUSTINESS THIS AFTN SHOULD
DECREASE BY SUNSET.

OUTLOOK...
MONDAY NIGHT THROUGH THURSDAY...MVFR/IFR CEILING AND VISIBILITY
VALUES ARE POSSIBLE, ALONG WITH SCATTERED SHOWERS, DURING THE
OVERNIGHT AND MORNING HOURS EACH DAY. MAINLY VFR CONDITIONS ARE
EXPECTED DURING THE AFTERNOON AND EVENING HOURS, EXCEPT IN
SCATTERED SHOWERS AND THUNDERSTORMS. THE WIND SHOULD BE MAINLY 10
KNOTS OR LESS AND IT MAY FAVOR THE EAST TO SOUTH QUADRANT.

THURSDAY NIGHT AND FRIDAY...MAINLY VFR WITH A SOUTH WIND 10 KNOTS
OR LESS. SOME LATE NIGHT AND EARLY MORNING VISIBILITY RESTRICTIONS
ARE POSSIBLE.

&&

.MARINE...
PROLONGED NE TO E FLOW IS EXPECTED WITH AN AREA OF LOW PRESSURE
OFF THE DELMARVA COAST AND FCST TO MOVE WWD TONIGHT AND MONDAY.
SEAS ARE ALREADY ABOVE 7 FT AT BUOY 44009 AND WHILE THEY REMAIN
BELOW SCA CRITERIA FURTHER N, THEY ARE EXPECTED TO RISE AS WELL.
THE PREV ISSUED SCA WILL REMAIN IN EFFECT AS A RESULT. THE WIND
WILL GUST THRU THE EVENING AND AROUND ANY SHOWERS THAT MAY
DEVELOP.

OUTLOOK...
WIND SPEEDS ARE FORECAST TO REMAIN BELOW THE SMALL CRAFT ADVISORY
CRITERION FOR THE PERIOD FROM MONDAY NIGHT THROUGH FRIDAY.

WAVE HEIGHTS ON OUR OCEAN WATERS ARE EXPECTED TO REMAIN AT 5 FEET
OR GREATER INTO THE MID WEEK PERIOD, AS TROPICAL STORM ALBERTO
PASSES WELL TO OUR EAST. FOR NOW, THE SMALL CRAFT ADVISORY ON OUR
OCEAN WATERS HAS BEEN EXTENDED UNTIL 600 AM TUESDAY.

&&

.FIRE WEATHER...
THERE WERE POCKETS WHERE HUMIDITY VALUES REMAINED BELOW 30% AND
THE WIND WAS GUSTING TO AROUND 20 MPH, MAINLY OVER NRN SECTIONS OF
THE REGION. HOWEVER, THE OVERALL TREND IN HUMIDITY IS UPWARD. SO
THERE WILL BE SOME ENHANCED FIRE WX CONCERNS FOR THE NEXT COUPLE
OF HOURS, AS THE WIND DECREASES, TEMPS DECREASE AND MOISTURE
INCREASES WITH LOW PRESSURE OFF THE COAST MOVING WWD, ANY FIRE WX
CONCERNS SHOULD SUBSIDE.

&&

.TIDES/COASTAL FLOODING...
IT STILL APPEARS, BASED ON THE LATEST GUIDANCE THAT MOST, IF NOT
ALL SITES, WILL REMAIN BELOW COASTAL FLOODING CRITERIA THROUGH
MONDAY (AND LIKELY BEYOND). THE BEST CHANCE FOR EXCEEDING
THRESHOLDS WOULD BE OVER SRN WATERS.

&&

.RIP CURRENTS...
THE COMBINATION OF A 4 TO 6 FOOT EAST TO SOUTHEAST SWELL WITH AN
8 TO 10 SECOND PERIOD AND 1 TO 4 FEET OF WIND WAVES ON TOP OF
THAT... GENERATED BY AN INCREASING NORTHEAST WIND OF 20 TO
OCCASIONALLY 25 KNOTS...PRODUCES AN ENVIRONMENT THAT RAISES THE
RISK OF RIP CURRENTS INTO THE HIGH LIKELIHOOD CATEGORY.

WE KNOW WATER TEMPERATURES ARE COLD FOR MOST RECREATIONAL BATHERS...
GENERALLY BETWEEN 55 AND 60 DEGREES...AND SO THERE ARE PROBABLY
FEW SWIMMERS. HOWEVER...IN THE INTEREST OF PROTECTION OF LIFE...
AND SINCE OUR SURF ZONE FORECAST HAS STARTED THIS SEASON...THE
HEADLINE INFORMATION HAS BEEN ISSUED.

DIMINISHING WIND AND SEAS ON MONDAY SHOULD LOWER THE RISK TO
MODERATE.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...HIGH RIP CURRENT RISK UNTIL 11 PM EDT THIS EVENING FOR NJZ014-
     024>026.
DE...HIGH RIP CURRENT RISK UNTIL 11 PM EDT THIS EVENING FOR DEZ004.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT TUESDAY FOR ANZ452>455.
     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 AM EDT TUESDAY
     FOR ANZ450-451.
     SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT FOR ANZ430-431.

&&

$$

SYNOPSIS...IOVINO
NEAR TERM...NIERENBERG
SHORT TERM...NIERENBERG
LONG TERM...IOVINO
AVIATION...IOVINO/NIERENBERG
MARINE...IOVINO/NIERENBERG
FIRE WEATHER...NIERENBERG
TIDES/COASTAL FLOODING...NIERENBERG
RIP CURRENTS...DRAG

000
FXUS61 KCTP 201921
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
321 PM EDT SUN MAY 20 2012

.SYNOPSIS...
HIGH PRESSURE WILL PUSH WELL OFF THE COASTAL NEW ENGLAND WATERS
TONIGHT. AN INCREASING MOIST EAST TO SOUTHEAST FLOW WILL PUSH
ATLANTIC MOISTURE INTO CENTRAL PENNSYLVANIA LATE TONIGHT AND
MONDAY...AS AN UPPER LEVEL TROF MOVES TO THE CENTRAL GREAT LAKES
ON MONDAY. THIS WILL BRING AN INCREASING CHANCE OF SHOWERS TO ALL
OF CENTRAL PA ON MONDAY. AN UPPER LEVEL LOW OVER THE SOUTHEAST
WILL SLOWLY TRACK NORTHEASTWARD THROUGH MID WEEK...KEEPING
UNSETTLED WEATHER ALONG THE EASTERN SEABOARD...AND A DAILY CHANCE
OF SHOWERS AND THUNDERSTORMS OVER CENTRAL PENNSLYLVANIA.
PENNSYLVANIA WILL BE ON THE EDGE OF A BUILDING A LARGE UPPER HIGH
ACROSS THE TENNESSEE RIVER VALLEY AND SOUTHEASTERN STATES BY THE
END OF THIS WEEK.

&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
LLVL MOISTURE PUSHING WESTWARD INTO NRN MD FROM DE AND SOUTHERN
NEW JERSEY THIS AFTERNOON AS DEEPER LLVL ELY FLOW CONTS TO DRAW
ATLANTIC MOISTURE INLAND. CLEAR SKIES SHOULD PREVAIL FOR MOST OF
CENTRAL PA THIS EVENING...WITH LOW CLOUDS APPROACHING LATER THIS
EVENING ACROSS LANCASTER AND YORK COUNTIES. AFTER SUNSET...CLOUDS
WILL CONTINUE THEIR TREK WESTWARD AND NORTHWARD...EVENTUALLY
OVERSPREADING MOST IF NOT ALL OF CENTRAL BY BY 12Z MON. FAR
NORTHWEST AREAS MAY ESCAPE BKN CIGS. ALL BUT THE LOWER SUSQ. SHOULD
REMAIN DRY TONIGHT...BUT AREAS OF DRIZZLE AND LIGHT SHOWERS ARE
CERTAINLY POSSIBLE IN THE DEEPER MARITIME AIR MASS OVER THE LOWER
SUSQ RIVER VALLEY BEFORE 12Z. OVERNIGHT MINS WILL BE MUCH MILDER
WITH THE INCREASING CLOUD COVER...AND WILL RANGE FROM THE LOWER
50S IN THE NORTH TO THE MID TO UPPER 50S SOUTHEAST.

&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/...
NO CHANGES TO THE THINKING ON MONDAY AS UPPER LOW OVER THE
SOUTHEAST CONUS WILL LIFT NORTH ALONG THE E COAST. ASSOCIATED
MOIST...EASTERLY LL JET AND UPPER LVL DIVERGENCE PRECEDING THE
UPPER LOW WILL LIKELY BRING SCT SHOWERS TO CENTRAL PA BEGINNING
LATE TONIGHT ACROSS THE SOUTHEAST ZONES AND OVERSPREADING THE
REST OF CENTRAL PA DURING MONDAY. CLOUD COVER...PRECIP AND
EASTERLY FLOW OFF THE ATLANTIC WILL RESULT IN A MUCH COOLER
MONDAY WITH MAX TEMPS ONLY ARND 70F. GEFS DATA SHOWING HIGHEST
PWATS ACROSS SOUTHEAST PA...WHERE THE BEST CHC OF MEASURABLE
RAINFALL IS EXPECTED SUN NITE/MONDAY.

DOWNSLOPING SE FLOW WILL RESULT IN PARTIAL SUNSHINE AND A
SOMEWHAT WARMER MONDAY OVR WARREN COUNTY...WHERE A LATE DAY
TSRA IS POSSIBLE. CAPE VALUES IN THE 600 TO 800JK-1 RANGE
ACROSS WARREN CO MON EVENING. FURTHER EAST...A COOLER MORE
STABLE EASTERLY FLOW SHOULD PRECLUDE THUNDER.

&&

.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
NOT A LOT OF CHANGE FROM THE FCST PACKAGE YESTERDAY.

STILL LOOKS LIKE NORTHERN SYSTEM OFF THE COAST WILL PIVOT AROUND
ALBERTO AND MOVE WESTWARD...BRINGING SHOWERS TO THE AREA ON TUE.
MAIN CHC WILL BE MONDAY INTO TUE.

DID UP TEMPS SOME ON TUE...ALSO SOME CHC OF A THUNDERSTORM WITH
THE WARMER TEMPS.

SHOWERS COULD LINGER INTO WED...ESPECIALLY ACROSS THE SE WITH
THE FRONT.

TRIED TO GO WITH THE MID SHIFT FCST AND HAVE SOME PERIODS OF
DRY WEATHER. HARD TO FIND A LOT OF DRY PERIODS...AS REMAINS OF
CUTOFF COULD KEEP A FEW SHOWERS ACROSS EASTERN AREAS...WHERE
FAR NW AREAS COULD SEE SOME FROM THE COLD FRONT LATE IN THE
WEEK.

WENT WITH A DRY FCST FOR SUNDAY...IT WILL BE CLOSE...HARD TO
SEE THE EAST...WEST COLD FRONT DROPPING TOO FAR SOUTH.

TEMPS WILL BE WARM THROUGHOUT THE PERIOD...ABOVE NORMAL.

&&

.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
A RIDGE OF HIGH PRESSURE WILL MOVE OFF THE NEW ENGLAND COAST
TONIGHT. A PERIOD OF VFR CONDITIONS WITH CLEAR SKIES AND LIGHT
EASTERLY WINDS WILL CONTINUE THROUGH LATE TONIGHT.

CLOUDS INCREASE LATE TONIGHT AND MONDAY AS A DEEP LOW LIFTS INTO
THE REGION FROM THE SOUTHEAST. SHOWERY WEATHER RETURNS EARLY
MONDAY WITH MVFR TO IFR CONDITIONS IN LOW CIGS DEVELOP IN THE
LOWER SUSQ /MDT-LNS AND POSS IPT/ AFTER 06Z MON. LOWER CIGS AND
RAIN SHOWERS SPREAD FURTHER INTO CENTRAL MTNS DURING THE DAY MON.

OUTLOOK...
MON...SCATTERED MVFR /IFR SE/ CIGS AND VSBYS IN SHOWERS AND ISOLD
THUNDERSTORMS.
MON NIGHT-WED...MORE WIDESPREAD MVFR/IFR CIGS AND VSBYS LIKELY IN
SHOWERS AND SCTD TSRA.
THU...PRIMARILY VFR. SCT SHRA/TSTM POSS MAINLY SE.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...GRUMM/FITZGERALD
NEAR TERM...DEVOIR
SHORT TERM...DEVOIR
LONG TERM...MARTIN
AVIATION...DEVOIR/RXR

000
FXUS61 KPBZ 201921
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
321 PM EDT SUN MAY 20 2012

.SYNOPSIS...
BY MONDAY AFTERNOON...THE REGION WILL BE SQUEEZED BY AREAS OF
PRECIPITATION FROM THE WEST AND EAST. THE BEST CHANCE FOR SHOWERS
WILL ARRIVE ON TUESDAY BEFORE CONDITIONS SLOWLY DRY OUT.

&&

.NEAR TERM /THROUGH MONDAY/...
ALTHOUGH TROPICAL STORM ALBERTO OFF THE COAST OF SOUTH CAROLINA HAS
BEEN THE MAIN WEATHER FOCUS IN THE LAST DAY...AN EXTRATROPICAL STORM
OFF THE VIRGINIA COAST WILL BE ONE OF THE PRIMARY FACTORS IN THE
LOCAL FORECAST FOR THE NEXT 48 HOURS. HIGH PRESSURE RIDGE CURRENTLY
OVER THE REGION WILL BE PUSHED OFF TO THE NORTHEAST OVERNIGHT...WITH
THE VIRGINIA LOW SLOWLY MOVING ONSHORE DURING THAT TIME PERIOD.
WITH THE SLOW PROGRESS...ONLY A SLIGHT CHANCE OF SHOWERS FOR THE
RIDGES IS FORECAST LATE TONIGHT. MEANWHILE...A COLD FRONT CURRENTLY
STRETCHING FROM UPPER MICHIGAN SOUTH INTO MISSOURI WILL MOVE
EAST...MOVING INTO INDIANA BY MONDAY MORNING.

TO THE EAST...LOW PRESSURE WILL SLOWLY DISSIPATE AS IT MOVES INTO
CENTRAL PENNSYLVANIA...THEN VEERS INTO NEW YORK. THIS WILL INCREASE
THE CHANCE OF SHOWERS AND THUNDERSTORMS FROM EAST TO WEST...BUT
LIKELY POPS WILL REMAIN EAST OF US. AT THE SAME TIME...THE COLD
FRONT WILL APPROACH THE WESTERN EDGE OF THE FORECAST AREA BY LATE
MONDAY AFTERNOON. ALTHOUGH INSTABILITY VALUES WILL BE LIGHT TO
MODERATE...WIND PROFILES UP TO 25 KFT ARE NEARLY CALM...WHICH SHOULD
PREVENT ANY CHANCE FOR SEVERE WEATHER. WITH CLOUD COVER
OVERSPREADING EASTERN COUNTIES THE MOST...LOWS WILL BE HELD TO THE
LOW AND MID 70S EAST...WITH MID 80S STILL POSSIBLE WEST.

&&

.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
COLD FRONT WILL CONTINUE TO PROGRESS EAST MONDAY NIGHT...BUT WITH
LITTLE IN THE WAY OF DEEP MOISTURE. WILL CONTINUE CHANCE POPS MONDAY
NIGHT INTO TUESDAY...WITH LIKELY POPS ONLY MENTIONED ACROSS THE
RIDGES TUESDAY AFTERNOON WHERE OROGRAPHIC LIFT SHOULD HELP TO
GENERATE SHOWERS. INSTABILITY STILL LOOKS QUITE LIMITED...AND HAVE
CONTAINED THUNDER MENTION ONLY TO LOCATIONS WITH LIKELY POPS. WITH
WIDESPREAD CLOUD COVER...HIGHS EVERYWHERE WILL DROP BACK TO
SEASONABLE LEVELS.

BY TUESDAY NIGHT...THE UPPER LEVEL TROUGH ASSOCIATED WITH THE COLD
FRONT IS EXPECTED TO CLOSE OFF INTO AN UPPER LOW OVER THE CAROLINAS
AND REMAIN STATIONARY INTO WEDNESDAY. THE CUTOFF FLOW IS EXPECTED TO
KEEP SKIES PARTLY/MOSTLY CLOUDY...WITH A CHANCE OF SHOWERS
CONTINUING TO PERSIST. WITH SOME BREAKS IN CLOUD COVER...HIGHS WILL
RISE A COUPLE OF DEGREES FROM TUESDAY/S VALUES.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
A NEARLY STATIONARY UPPER LEVEL LOW/TROUGH WILL BE NEAR THE
CAROLINAS. HOWEVER...MODEL SOLUTIONS DIFFER. AT THIS TIME ENSEMBLE
TREND IS STILL TO KEEP A DRIER FORECAST FOR THE COUNTY WARNING
AREA...SO WILL CONTINUE THE TREND. THE PERIOD IS PROJECTED TO BE
WARM WITH ABOVE AVERAGE TEMPERATURES APPROACHING 90 DEGREES AND
SFC DEWPOINTS IN THE LOW TO MID 60S FOR THE START OF THE MEMORIAL
DAY WEEKEND.

&&

.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
THERE WILL BE MOSTLY CLEAR SKIES AND LIGHT WINDS THROUGH MONDAY
MORNING. SOME EARLY MORNING VISIBILITY RESTRICTIONS EXPECTED
ACROSS EASTERN OH IN THE KZZV AREA TO AROUND 5 MILES DUE TO HZ/BR.
MID CLOUDS DECK WILL WORK INTO THE AREA MONDAY.

.OUTLOOK...MONDAY NIGHT THROUGH FRIDAY...
MOISTURE INCREASES FROM THE EAST AS LOW PRESSURE MOVES UP THE
EASTERN SEABOARD. INCREASE IN LOW LEVEL MOISTURE MAY SET OFF
ISOLATED TRW- LATE MONDAY THROUGH WEDNESDAY WITH MVFR
RESTRICTIONS IN AND NEAR TRW-. SFC DEWPOINTS INCREASE THROUGH THE
PERIOD AND WILL RESULT IN VISIBILITY RESTRICTIONS DUE TO HZ/BR AT
MOST AIRPORT LOCATIONS DURING EARLY MORNING HOURS WEDNESDAY AND
THURSDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$

000
FXUS61 KCTP 201826
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
226 PM EDT SUN MAY 20 2012

.SYNOPSIS...
HIGH PRESSURE WILL PUSH WELL OFF THE COASTAL NEW ENGLAND WATERS
TONIGHT. AN INCREASING MOIST EAST TO SOUTHEAST FLOW WILL PUSH
ATLANTIC MOISTURE INTO CENTRAL PENNSYLVANIA LATE TONIGHT AND
MONDAY...AS AN UPPER LEVEL TROF MOVES TO THE CENTRAL GREAT LAKES
ON MONDAY. THIS WILL BRING AN INCREASING CHANCE OF SHOWERS TO ALL
OF CENTRAL PA ON MONDAY. AN UPPER LEVEL LOW OVER THE SOUTHEAST
WILL SLOWLY TRACK NORTHEASTWARD THROUGH MID WEEK...KEEPING
UNSETTLED WEATHER ALONG THE EASTERN SEABOARD...AND A DAILY CHANCE
OF SHOWERS AND THUNDERSTORMS OVER CENTRAL PENNSLYLVANIA. PENNSYLVANIA
WILL BE ON THE EDGE OF A BUILDING A LARGE UPPER HIGH ACROSS THE
TENNESSEE RIVER VALLEY AND SOUTHEASTERN STATES BY THE END OF THIS WEEK.


&&

.NEAR TERM /THROUGH TONIGHT/...
LLVL MOISTURE PUSHING WESTWARD INTO NRN MD FROM DE AND SOUTHERN
NEW JERSEY THIS AFTERNOON AS DEEPER LLVL ELY FLOW CONTS TO DRAW
ATLANTIC MOISTURE INLAND. CLEAR SKIES SHOULD PREVAIL FOR MOST OF
CENTRAL PA THIS EVENING...WITH LOW CLOUDS APPROACHING LATER THIS
EVENING ACROSS LANCASTER AND YORK COUNTIES. AFTER SUNSET...CLOUDS
WILL CONTINUE THEIR TREK WESTWARD AND NORTHWARD...EVENTUALLY
OVERSPREADING MOST IF NOT ALL OF CENTRAL BY BY 12Z MON. FAR
NORTHWEST AREAS MAY ESCAPE BKN CIGS. ALL BUT THE LOWER SUSQ. SHOULD
REMAIN DRY TONIGHT...BUT AREAS OF DRIZZLE AND LIGHT SHOWERS ARE
CERTAINLY POSSIBLE IN THE DEEPER MARITIME AIR MASS OVER THE LOWER
SUSQ RIVER VALLEY BEFORE 12Z. OVERNIGHT MINS WILL BE MUCH MILDER
WITH THE INCREASING CLOUD COVER...AND WILL RANGE FROM THE LOWER
50S IN THE NORTH TO THE MID TO UPPER 50S SOUTHEAST.

&&

.SHORT TERM /MONDAY/...
NO CHANGES TO THE THINKING ON MONDAY AS UPPER LOW OVER THE
SOUTHEAST CONUS WILL LIFT NORTH ALONG THE E COAST. ASSOCIATED
MOIST...EASTERLY LL JET AND UPPER LVL DIVERGENCE PRECEDING THE
UPPER LOW WILL LIKELY BRING SCT SHOWERS TO CENTRAL PA BEGINNING
LATE TONIGHT ACROSS THE SOUTHEAST ZONES AND OVERSPREADING THE REST
OF CENTRAL PA DURING MONDAY. CLOUD COVER...PRECIP AND EASTERLY
FLOW OFF THE ATLANTIC WILL RESULT IN A MUCH COOLER MONDAY WITH MAX
TEMPS ONLY ARND 70F. GEFS DATA SHOWING HIGHEST PWATS ACROSS
SOUTHEAST PA...WHERE THE BEST CHC OF MEASURABLE RAINFALL IS
EXPECTED SUN NITE/MONDAY.

DOWNSLOPING SE FLOW WILL RESULT IN PARTIAL SUNSHINE AND A SOMEWHAT
WARMER MONDAY OVR WARREN COUNTY...WHERE A LATE DAY TSRA IS POSSIBLE.
CAPE VALUES IN THE 600 TO 800JK-1 RANGE ACROSS WARREN CO MON
EVENING. FURTHER EAST...A COOLER MORE STABLE EASTERLY FLOW SHOULD
PRECLUDE THUNDER.

&&

.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
OPERATIONAL AND ENSEMBLE MODEL DATA ALL INDICATE THAT AS E COAST
UPPER LOW OPENS UP AND LIFTS INTO THE CANADIAN MARITIMES...UPSTREAM
SHORTWAVE WILL DEEPEN AND CUT OFF OVR THE CENTRAL APPALACHIANS DURING
THE MIDDLE OF NEXT WEEK. ALTHOUGH MINOR MDL DIFFERENCES REMAIN WITH
RESPECT TO TIMING AND TRACK OF THIS FEATURE...ENOUGH SUPPORT IN THE
MDL DATA TO MENTION THE CHC OF DIURNALLY ENHANCED SHRA/TSRA
TUES-THURS. NEARLY ALL MDL DATA TRACKS TS ALBERTO WELL EAST OF PA
TUE NIGHT WITH NO DIRECT IMPACT ON PA.

EASTERLY FLOW MONDAY AND APPROACHING SHORT WAVE/FRONT TUESDAY
WILL LIKELY BRING 48HR RAINFALL OF BTWN 0.25 AND 1 INCH TO MUCH
OF CENTRAL/EASTERN PA BASED ON BLEND OF LATEST OPER AND ENSEMBLE
MDL QPF.

WARMER WX APPEARS VERY LIKELY TOWARD THE END OF THE WEEK WHEN ALL
MDL DATA INDICATES A BUILDING UPPER LVL RIDGE OVER THE OHIO
VALLEY. HOWEVER...PA MAY BE ON PERIPHERY OF THIS FEATURE...PLACING
AT LEAST NORTHERN PA IN RING OF FIRE WITH CHC OF PM CONVECTION.

&&

.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
A RIDGE OF HIGH PRESSURE WILL MOVE OFF THE NEW ENGLAND COAST TONIGHT.
A PERIOD OF VFR CONDITIONS WITH CLEAR SKIES AND LIGHT EASTERLY
WINDS WILL CONTINUE THROUGH LATE TONIGHT.

CLOUDS INCREASE LATE TONIGHT AND MONDAY AS A DEEP LOW LIFTS INTO
THE REGION FROM THE SOUTHEAST. SHOWERY WEATHER RETURNS EARLY
MONDAY WITH MVFR TO IFR CONDITIONS IN LOW CIGS DEVELOP IN THE
LOWER SUSQ /MDT-LNS AND POSS IPT/ AFTER 06Z MON. LOWER CIGS AND
RAIN SHOWERS SPREAD FURTHER INTO CENTRAL MTNS DURING THE DAY MON.

OUTLOOK...
MON...SCATTERED MVFR /IFR SE/ CIGS AND VSBYS IN SHOWERS AND ISOLD
THUNDERSTORMS.
MON NIGHT-WED...MORE WIDESPREAD MVFR/IFR CIGS AND VSBYS LIKELY IN
SHOWERS AND SCTD TSRA.
THU...PRIMARILY VFR. SCT SHRA/TSTM POSS MAINLY SE.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...DEVOIR
NEAR TERM...DEVOIR
SHORT TERM...DEVOIR
LONG TERM...GRUMM/FITZGERALD
AVIATION...DEVOIR/RXR

000
FXUS61 KPBZ 201752
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
152 PM EDT SUN MAY 20 2012

.SYNOPSIS...
HIGH PRESSURE WILL ALLOW FOR DRY AND UNSEASONABLY WARM WEATHER TO
CONTINUE INTO EARLY MONDAY. THE CHANCE OF SHOWERS AND THUNDERSTORMS
WILL RETURN AS A LOW PULLS MOISTURE INTO THE AREA FROM THE SOUTHEAST
AND A FRONTAL BOUNDARY APPROACHES FROM THE WEST.

&&

.NEAR TERM /THROUGH TONIGHT/...
PRIMARY TWEAK WITH 115 UPDATE WAS TO BUMP UP HIGH TEMPERATURES
ANOTHER DEGREE. HIGH PRESSURE WILL REMAIN IN CONTROL OF WEATHER
THROUGH THIS PERIOD. SOME CUMULUS HAS MANAGED TO DEVELOP SOUTH OF
PITTSBURGH...BUT WITH A 30 DEGREE DEWPOINT DEPRESSION...THIS IS
NOT EXPECTED TO SPREAD MUCH. CLOUD COVER SHOULD GENERALLY COME
WITH HIGH CLOUDS FROM TROPICAL STORM ALBERTO OFF THE SOUTH
CAROLINA COAST. A SLIGHT CHANCE OF SHOWERS WILL BEGIN TO WORK INTO
THE RIDGES LATE TONIGHT.

&&

.SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/...
THE GFS/ECMWF/UKMET CONTINUE TO SUGGEST THAT AS THE RIDGE
TRANSFERS TOWARDS THE COAST...THE CUTOFF LOW WILL RETROGRADE
HELPING TO BRING MOISTURE TOWARDS THE NORTHEAST AND OHIO VALLEY
MONDAY. THUS...CONTINUED TO CARRY SLIGHT CHANCE POPS STARTING
MONDAY MORNING IN THE RIDGES AND INCREASING AS THE DAY PROGRESSES
AND LOWER LEVELS MOISTEN. IN ADDITION...THE UPPER LEVEL TROUGH
OVER THE MIDWEST WILL MAKE ITS APPROACH LATER MONDAY AFTERNOON AND
WITH IT MODELS MAINTAIN ENOUGH INSTABILITY FOR THUNDERSTORM
DEVELOPMENT LATER MONDAY INTO TUESDAY AS THE COLD FRONT TAKES ITS
TIME CROSSING THE REGION.

MODEL AGREEMENT BEGINS TO DIVERGE LATER INTO TUESDAY AS THE ECMWF
IS SLOWER WITH THE FRONTAL PASSAGE AND IN ADDITION SUGGESTS THE
DEVELOPMENT OF ANOTHER 500HPA CUTOFF LOW CONTINUING PRECIPITATION
CHANCES THROUGHOUT THE DAY WEDNESDAY. THE GFS MAINTAINS AN OPEN
WAVE AND THUS HAS A FASTER SOLUTION ENDING PRECIPITATION SOONER ON
WEDNESDAY. DECIDED TO REMAIN CLOSER TO THE GFS BUT KEPT SLIGHT
CHANCE POPS THROUGH WEDNESDAY DUE TO THE UNCERTAINTY.

&&

.LONG TERM /FRIDAY THROUGH SUNDAY/...
A NEARLY STATIONARY UPPER LEVEL LOW/TROUGH NEAR THE CAROLINAS.
HOWEVER...MODEL SOLUTIONS DIFFER. AT THIS TIME ENSEMBLE TREND IS
STILL TO KEEP A DRIER FORECAST FOR THE COUNTY WARNING AREA...SO WILL
CONTINUE THE TREND. THE PERIODS IS PROJECTED TO BE WARM WITH ABOVE
AVERAGE TEMPERATURES APPROACHING 90 DEGREES AND SFC DEWPOINTS IN
THE LOW TO MID 60S FOR THE START OF THE MEMORIAL DAY WEEKEND.

&&

.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
MOSTLY CLEAR SKIES AND LIGHT WINDS THROUGH MONDAY MORNING. SOME
EARLY MORNING VISIBILTY RESTRICTIONS EXPECTED ACROSS EASTERN OH
IN THE KZZV AREA TO AROUND 5 MILES DUE TO HZ/BR. MID CLOUDS DECK WILL
WORK INTO THE AREA MONDAY.

.OUTLOOK...MONDAY NIGHT THROUGH FRIDAY...
MOISTURE INCREASES FROM THE EAST AS LOW PRESSURE MOVES UP THE
EASTERN SEABOARD. INCREASE IN LOW LEVEL MOISTURE MAY SET OFF
ISOLATED TRW- LATE MONDAY THROUGH WEDNESDAY WITH MVFR
RESTRICTIONS IN AND NEAR TRW-. SFC DEWPOINTS INCREASE THROUGH THE
PERIOD AND WILL RESULT IN VISIBILITY RESTRICTIONS DUE TO HZ/BR AT
MOST AIRPORT LOCATIONS DURING EARLY MORNING HOURS WEDNESDAY AND
THURSDAY.
&&


.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$

000
FXUS61 KPBZ 201716
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
116 PM EDT SUN MAY 20 2012

.SYNOPSIS...
HIGH PRESSURE WILL ALLOW FOR DRY AND UNSEASONABLY WARM WEATHER TO
CONTINUE INTO EARLY MONDAY. THE CHANCE OF SHOWERS AND THUNDERSTORMS
WILL RETURN AS A LOW PULLS MOISTURE INTO THE AREA FROM THE SOUTHEAST
AND A FRONTAL BOUNDARY APPROACHES FROM THE WEST.

&&

.NEAR TERM /THROUGH TONIGHT/...
PRIMARY TWEAK WITH 115 UPDATE WAS TO BUMP UP HIGH TEMPERATURES
ANOTHER DEGREE. HIGH PRESSURE WILL REMAIN IN CONTROL OF WEATHER
THROUGH THIS PERIOD. SOME CUMULUS HAS MANAGED TO DEVELOP SOUTH OF
PITTSBURGH...BUT WITH A 30 DEGREE DEWPOINT DEPRESSION...THIS IS
NOT EXPECTED TO SPREAD MUCH. CLOUD COVER SHOULD GENERALLY COME
WITH HIGH CLOUDS FROM TROPICAL STORM ALBERTO OFF THE SOUTH
CAROLINA COAST. A SLIGHT CHANCE OF SHOWERS WILL BEGIN TO WORK INTO
THE RIDGES LATE TONIGHT.

&&

.SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/...
THE GFS/ECMWF/UKMET CONTINUE TO SUGGEST THAT AS THE RIDGE
TRANSFERS TOWARDS THE COAST...THE CUTOFF LOW WILL RETROGRADE
HELPING TO BRING MOISTURE TOWARDS THE NORTHEAST AND OHIO VALLEY
MONDAY. THUS...CONTINUED TO CARRY SLIGHT CHANCE POPS STARTING
MONDAY MORNING IN THE RIDGES AND INCREASING AS THE DAY PROGRESSES
AND LOWER LEVELS MOISTEN. IN ADDITION...THE UPPER LEVEL TROUGH
OVER THE MIDWEST WILL MAKE ITS APPROACH LATER MONDAY AFTERNOON AND
WITH IT MODELS MAINTAIN ENOUGH INSTABILITY FOR THUNDERSTORM
DEVELOPMENT LATER MONDAY INTO TUESDAY AS THE COLD FRONT TAKES ITS
TIME CROSSING THE REGION.

MODEL AGREEMENT BEGINS TO DIVERGE LATER INTO TUESDAY AS THE ECMWF
IS SLOWER WITH THE FRONTAL PASSAGE AND IN ADDITION SUGGESTS THE
DEVELOPMENT OF ANOTHER 500HPA CUTOFF LOW CONTINUING PRECIPITATION
CHANCES THROUGHOUT THE DAY WEDNESDAY. THE GFS MAINTAINS AN OPEN
WAVE AND THUS HAS A FASTER SOLUTION ENDING PRECIPITATION SOONER ON
WEDNESDAY. DECIDED TO REMAIN CLOSER TO THE GFS BUT KEPT SLIGHT
CHANCE POPS THROUGH WEDNESDAY DUE TO THE UNCERTAINTY.

&&

.LONG TERM /THURSDAY THROUGH SATURDAY/...
12Z GFS/00Z ECMWF HAVE DIFFERENT DEPICTIONS IN THE EXTENDED...AND
THEREFORE CONFIDENCE IS BELOW AVERAGE. BOTH MODELS SHOW GENERAL
AGREEMENT THAT THERE WILL BE A NEARLY STATIONARY UPPER LEVEL
LOW/TROUGH NEAR THE CAROLINAS. HOWEVER...MULTIPLE RUNS OF THE GFS
KEEPS THIS FEATURE OVER THE ATLANTIC OCEAN WITH JUST SOME CLOUDS
LOCALLY...WHILE THE ECMWF HAS THE FEATURE INLAND ALONG THE EAST
COAST AND SPREADS RAIN AS FAR WEST AS WEST VIRGINIA AND EASTERN
OHIO. WITH NAEFS AND ECMWF ENSEMBLE KEEPING THE PATTERN A LITTLE
DRIER...HAVE ALSO STUCK WITH A DRIER FORECAST. IF THIS HOLDS...AND
THE GFS FORECAST VERIFIES...THIS PERIOD WILL BE QUITE WARM. GFS
BIAS-CORRECTED GRIDS AND NAEFS METEOGRAMS SUGGEST THAT 90 DEGREES IS
NOT OUT OF THE QUESTION FOR THE START OF THE MEMORIAL DAY WEEKEND.

&&

.AVIATION /17Z SUNDAY THROUGH THURSDAY/...
HIGH PRESSURE WILL KEEP SKIES MOSTLY CLEAR WITH ONLY A FEW CIRRUS.
WINDS BELOW 10 KTS FOR NEXT 24 HOURS.

.OUTLOOK...MONDAY THROUGH THURSDAY...
COLD FRONT APPROACHES FROM THE WEST ON MONDAY WHILE MOISTURE
INCREASES FROM THE EAST AS LOW PRESSURE MOVES UP THE EASTERN
SEABOARD. RESTRICTIONS POSSIBLE THROUGH WEDNESDAY. PRECIPITATION
SHOULD THEN SHIFT EAST OF THE AREA BY WEDNESDAY NIGHT WITH GENERAL
VFR THURSDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$

000
FXUS61 KPHI 201625
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1225 PM EDT SUN MAY 20 2012

.SYNOPSIS...
AN AREA OF LOW PRESSURE OFF THE MID-ATLANTIC COAST WILL DRIFT
WESTWARD ON LAND LATER TODAY INTO TONIGHT. MEANWHILE, TROPICAL STORM
ALBERTO WILL MEANDER OFF THE SOUTH CAROLINA COAST THROUGH MONDAY,
BEFORE MOVING NORTHEAST AND WEAKENING THROUGH WEDNESDAY. A
FRONTAL BOUNDARY IS FORECAST TO AFFECT THE AREA TUESDAY NIGHT INTO
WEDNESDAY, BEFORE SLOWLY MOVING TO OUR SOUTH THROUGH THURSDAY. HIGH
PRESSURE MAY THEN BUILD ACROSS THE AREA FROM THE NORTHEAST FRIDAY
INTO SATURDAY, WITH THE POSSIBILITY OF A COLD FRONT LATE SATURDAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MADE A FEW ADJUSTMENTS TO CLOUD COVER BASED ON LATEST SATELLITE
IMAGERY. ALSO ADJUSTED TEMPS WHERE NECESSARY. OTHERWISE PREVIOUS
FCST RATIONALE STILL LOOKED GOOD.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...
TONIGHT...A CONDUIT OF MOISTURE IN DEEP SE FLOW SHOULD NOT ONLY
DEVELOP SHOWERS ACROSS MOST OF THE AREA DURING THE NIGHT
/INSTABILITY BURST/ BUT 0.25 TO AS MUCH AS ISOLATED 1 INCH AMTS
ARE FCST BY 12Z MONDAY IN NJ/DE WITH LESSER AMTS IN PA/MD.

ISO THUNDER IS POSSIBLE IN COASTAL NJ/DE AFTER 05Z WITH INSTABILITY
ALOFT...VIA A SWI SUBZERO...SOME CAPE ON THE SE SIDE OF THE INVERTED
TROUGH /SE BL WIND/. THE PROB FOR THUNDER IS LOW ENOUGH NOT TO BE
IN THE LEGACY ZONES BUT DOES SHOW UP IN THE MORE DETAILED
POINT/CLICK INFORMATION.

BLENDED NCEP STATISTICAL GUIDANCE FOR WINDS/TEMPS.

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...
BROAD TROUGHING ALOFT WILL REMAIN ACROSS THE EAST COAST FOR MUCH OF
THE WEEK, WHICH WILL KEEP UNSETTLED WEATHER FOR MUCH OF THE EXTENDED
FORECAST. ON MONDAY, THE SURFACE LOW THAT MOVED INLAND TO OUR SOUTH
WILL WEAKEN, BUT AN ABUNDANCE OF MOISTURE WILL CONTINUE TO FLOW IN
ACROSS THE AREA. PWAT VALUES REACH 1.5-1.75 INCHES DURING THE DAY
MONDAY, SO THERE COULD BE A PERIOD OF MODERATE TO HEAVY RAIN ACROSS
THE AREA. THERE IS SOME INSTABILITY IN THE ATMOSPHERE, SO WE HAVE
ADDED A CHANCE OF THUNDERSTORMS.

A FRONTAL BOUNDARY IS EXPECTED TO APPROACH THE AREA TUESDAY, BEFORE
SETTLING ACROSS THE AREA TUESDAY NIGHT INTO WEDNESDAY. WITH THE
BROAD TROUGH ALOFT, SEVERAL VORT MAXES/SHORT WAVES WILL LIKELY CROSS
THE AREA DURING THIS TIME PERIOD. THEREFORE WE WILL KEEP A CHANCE OF
SHOWERS IN THE FORECAST, AND CONTINUE A CHANCE OF THUNDERSTORMS
SINCE THERE IS SOME INSTABILITY ACROSS THE AREA.

BY THURSDAY, THE FRONT SHOULD SINK TO OUR SOUTH, BUT FOR THURSDAY
THROUGH THE END OF THE WEEK, THE TROUGH ALOFT WILL BE SLOW TO PULL
OUT OF THE AREA. THIS WILL KEEP A SLIGHT CHANCE OF
SHOWERS/THUNDERSTORMS ACROSS THE AREA. THE SHOWER ACTIVITY WOULD
MOST LIKELY OCCUR DURING EACH AFTERNOON DUE TO THE DAYTIME HEATING.

THE NHC HAS NAMED TROPICAL STORM ALBERTO WHICH IS LOCATED OFF THE
SOUTH CAROLINA COAST. THE LATEST TRACK HAS THE STORM MEANDERING OFF
THE SOUTH CAROLINA COAST THROUGH MONDAY, THEN MOVING NORTHEAST AND
WEAKENING THROUGH WEDNESDAY. THE CURRENT TRACK KEEPS THE STORM AWAY
FROM OUR AREA, BUT WE WILL HAVE TO CONTINUE TO MONITOR THE FORECAST
IN CASE THE TRACK MOVES FURTHER WEST. VISIT THE NHC`S WEBSITE FOR
MORE INFORMATION ON THE TROPICAL STORM ALBERTO.

&&

.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.

VFR MOST AREAS. HOWEVER, MVFR CIGS HAVE REACHED KACY AND KMIV IS
ON THE CUSP RIGHT NOW AS LOW CLOUDS MOVE WWD FROM SYS OFF THE CST.
THESE CLOUDS SHOULD GRADUALLY SPREAD NWWD THIS AFTN COVERING MOST OF
SE NJ AND MOST OF DE BY 00Z/21. NE WIND GUSTS 20-25 KTS SHOULD
DEVELOP ACRS MUCH OF THE REGION. SCT SHOWERS DEVELOP VCNTY KACY THRU
MOST OF S DE SOMETIME DURING THE AFTN. FOR NOW THE FCST IN THE
TAFS IS NEAR 00Z BUT SUBJECT TO CHANGE BASED ON RADAR.

TONIGHT...MVFR CIGS SPREAD OVER ALL THE REGION DURING THE NIGHT AND
SHOWERS BECOME MORE WIDESPREAD. SHOWERS WILL BE BRIEFLY HEAVY IN
NJ/DE. ITS ALSO LIKELY THAT IFR CONDS DEVELOP IN SOME OF THE SHOWERS
AS WELL AS ST/FOG...MAINLY AFTER 05Z/21.


OUTLOOK...
MONDAY/MONDAY NIGHT...MVFR/IFR CIGS/VSBYS EXPECTED, ESPECIALLY WITH
SHOWERS. MOSTLY EAST/NORTHEAST WINDS AROUND 10-15 KNOTS.

TUESDAY/TUESDAY NIGHT...MVFR/IFR EARLY, POSSIBLY IMPROVING TO VFR BY
AFTERNOON EXCEPT IN SHOWERS/THUNDERSTORMS. EAST WINDS BECOMING
SOUTHEAST DURING THE DAY. MVFR/IFR CIGS/VSBYS POSSIBLE AT NIGHT.

WEDNESDAY/WEDNESDAY NIGHT...MOSTLY VFR, POSSIBLE MVFR IN
SHOWERS/THUNDERSTORMS DURING THE AFTERNOON. EAST/SOUTHEAST WINDS
5-10 KNOTS. MVFR/IFR CIGS/VSBYS POSSIBLE AT NIGHT.

THURSDAY...MVFR/IFR POSSIBLE EARLY, IMPROVING TO VFR BY AFTERNOON
EXCEPT IN SHOWERS/THUNDERSTORMS. SOUTHEAST WINDS AROUND 5-10 KNOTS.

&&

.MARINE...
TODAY AND TONIGHT...SCA CONTINUES AS POSTED. THE HAZARDOUS SEAS
HAVE BEEN IN PROGRESS OVER VIRTUALLY ALL THE ATLC WATERS FOR A DAY
NOW...THE EXCEPTION POSSIBLY IN PORTIONS OF ANZ450. ONSHORE WINDS
ARE MODELED TO INCREASE 5 TO 10 KTS TODAY THROUGHOUT THE WATERS
/HIGHER THAN YDY/ BEFORE WINDS SUBSIDE LATER TONIGHT. IF THE WIND
FCST IS CORRECT...SEAS TO 10 FEET WILL DEVELOP FOR THE DE COAST
TODAY. WE ADDED DE BAY TO SCA TODAY PER THE MODELED WIND INCREASE.

OUTLOOK...
THE SMALL CRAFT ADVISORY WILL REMAIN THROUGH MONDAY AS WAVEWATCH
GUIDANCE KEEPS SEAS ABOVE 5 FEET THROUGH THE TIME PERIOD. WE WILL
NEED TO CONTINUE TO MONITOR THE FORECAST TRACK FOR TROPICAL STORM
ALBERTO TO SEE IF ANY STRONG WINDS WILL MAKE IT ACROSS OUR WATERS.
THE LATEST TRACK FROM THE NHC KEEPS THE STORM FAR ENOUGH AWAY FROM
OUR WATERS TO NOT GET STORM FORCE WINDS. HOWEVER, SEAS MAY REMAIN
ELEVATED THROUGH WEDNESDAY, WHICH IS WHEN THE STORM IS EXPECTED TO
PASS TO OUR EAST.

&&

.FIRE WEATHER...
WE`LL CHECK WITH FORESTRY OFFICIALS AFTER 8AM TODAY TO SEE
WHETHER THEY PREFER AN SPS FOR THE 2P-5P PERIOD THIS AFTERNOON
FROM THE LEHIGH VALLEY INTO NW NJ WHEN RH IS BELOW 30 PCT...NE
WINDS WILL BE GUSTING TO 20 MPH...10 HR FUELS ARE IN THE 6 TO 9
PCT RANGE AFTER 4 SUCCESSIVE DRY DAYS.

&&

.TIDES/COASTAL FLOODING...
WITH A CONTINUED NORTHEAST TO EAST FLOW TONIGHT AND MONDAY, THERE
REMAINS THE POTENTIAL FOR SPOTTY MINOR TIDAL FLOODING...MAINLY THE
DELAWARE WATERS.

POSITIVE DEPARTURES AROUND A FOOT AND A QUARTER ARE NEEDED TO
REACH THE MINOR FLOODING THRESHOLD. WE WILL CONTINUE TO MONITOR
THE TRENDS ALONG WITH THE LATEST GUIDANCE.

00Z/20 MRPSSE GUIDANCE WILL BE AT LEAST HALF A FOOT TOO LOW FOR
TONIGHTS-SUNDAY NIGHT UPCOMING HIGH TIDE. SO FAR NO GUIDANCE
EXCEEDS THE THRESHOLD.

THINK WE WILL EVENTUALLY NEED A CF STATEMENT FOR TIDES NUDGING
MINOR FS OR JUST BLO BY 0.2 FT FOR THE TIDAL DELAWARE AS WELL AS
DE ATLC COAST THIS COMING SUNDAY NIGHT HIGH TIDE CYCLE.

BASICALLY THIS FOCUSES ON LEWES/REEDY/PHL.

NO ACTION ON THIS SHIFT DUE TO UNCERTAINTY AS WELL AS ONLY
"APPROACHING" THRESHOLD INSTEAD OF ANY CLEAR GUIDANCE EXCEEDING
THRESHOLD. PREDICTION FOR TONIGHT AT LEWES AT LEAST 5.7 AS PER OUR
LOCAL STATISTICAL PROGRAM.

&&

.RIP CURRENTS...
THE COMBINATION OF A 4 TO 6 FOOT EAST TO SOUTHEAST SWELL WITH AN 8
TO 10 SECOND PERIOD AND 1 TO 4 FEET OF WIND WAVES ON TOP OF THAT...
GENERATED BY AN INCREASING NORTHEAST WIND OF 20 TO OCCASIONALLY
25 KNOTS...PRODUCES AN ENVIRONMENT THAT RAISES THE RISK OF
RIP CURRENTS INTO THE HIGH LIKELIHOOD CATEGORY.

WE KNOW WATER TEMPERATURES ARE COLD FOR MOST RECREATIONAL BATHERS...
GENERALLY BETWEEN 55 AND 60 DEGREES...AND SO THERE ARE PROBABLY
FEW SWIMMERS. HOWEVER...IN THE INTEREST OF PROTECTION OF LIFE...
AND SINCE OUR SURF ZONE FORECAST HAS STARTED THIS SEASON...THE
HEADLINE INFORMATION HAS BEEN ISSUED.

DIMINISHING WIND AND SEAS ON MONDAY-TOMORROW SHOULD LOWER THE RISK TO
MODERATE.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...HIGH RIP CURRENT RISK UNTIL 11 PM EDT THIS EVENING FOR NJZ014-
     024>026.
DE...HIGH RIP CURRENT RISK UNTIL 11 PM EDT THIS EVENING FOR DEZ004.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT MONDAY FOR ANZ452>455.
     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 PM EDT MONDAY
     FOR ANZ450-451.
     SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR ANZ430-
     431.

&&

$$
SYNOPSIS...ROBERTSON
NEAR TERM...DRAG/NIERENBERG
SHORT TERM...DRAG
LONG TERM...ROBERTSON
AVIATION...DRAG/NIERENBERG/ROBERTSON
MARINE...DRAG/ROBERTSON
FIRE WEATHER...
TIDES/COASTAL FLOODING...
RIP CURRENTS...

000
FXUS61 KPBZ 201528
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
1128 AM EDT SUN MAY 20 2012

.SYNOPSIS...
HIGH PRESSURE WILL ALLOW FOR DRY AND UNSEASONABLY WARM WEATHER TO
CONTINUE INTO EARLY MONDAY. THE CHANCE OF SHOWERS AND THUNDERSTORMS
WILL RETURN AS A LOW PULLS MOISTURE INTO THE AREA FROM THE SOUTHEAST
AND A FRONTAL BOUNDARY APPROACHES FROM THE WEST.

&&

.NEAR TERM /THROUGH TONIGHT/...
WITH 1130AM UPDATE...MAIN CHANGE TO FORECAST WAS TO MODIFY HIGH
TEMPERATURES FOR THIS AFTERNOON. HAVE BUMPED UP HIGHS A COUPLE OF
DEGREES CONSIDERING TEMPS HAVE RISEN QUICKLY THIS MORNING.
PREVIOUS DISCUSSION FOLLOWS.

MID-LEVEL RIDGE WILL CONTINUE ITS HOLD OVER THE REGION FOR ONE
MORE PLEASANT DAY BEFORE PRECIPITATION CHANCES AND TEMPERATURES
CLOSER TO NORMAL RETURN. SOME CIRRUS ASSOCIATED WITH TS ALBERTO
WILL SPREAD OVERHEAD TODAY BUT DRY AIR IN THE LOWER LEVELS SHOULD
PREVENT CUMULUS DEVELOPMENT TODAY.

THE RIDGE WILL RIDE NORTH OVER THE UPPER LEVEL CUTOFF LOW OF BOTH
ALBERTO AND A LOW SITUATED TO ITS NORTHEAST...BEST DEPICTED ON IR
SATELLITE. A MORE SOUTHERLY WIND COMPONENT ALOFT AND GENERALLY
CLEAR SKIES SHOULD ALLOW FOR TEMPERATURES TO REBOUND TO WELL ABOVE
NORMAL ONCE AGAIN AS 850HPA TEMPS EXCEED +16C. HEDGED CLOSEST TO
MAV GUIDANCE THOUGH IT`S NOT UNREASONABLE THAT TEMPERATURES COULD
MAKE IT A DEGREE OR TWO WARMER THAN CURRENT FORECAST. OPTED TO GO
WITH A PERSISTENCE TEMPERATURE FORECAST.

&&

.SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/...
THE GFS/ECMWF/UKMET CONTINUE TO SUGGEST THAT AS THE RIDGE
TRANSFERS TOWARDS THE COAST...THE CUTOFF LOW WILL RETROGRADE
HELPING TO BRING MOISTURE TOWARDS THE NORTHEAST AND OHIO VALLEY
MONDAY. THUS...CONTINUED TO CARRY SLIGHT CHANCE POPS STARTING
MONDAY MORNING IN THE RIDGES AND INCREASING AS THE DAY PROGRESSES
AND LOWER LEVELS MOISTEN. IN ADDITION...THE UPPER LEVEL TROUGH
OVER THE MIDWEST WILL MAKE ITS APPROACH LATER MONDAY AFTERNOON AND
WITH IT MODELS MAINTAIN ENOUGH INSTABILITY FOR THUNDERSTORM
DEVELOPMENT LATER MONDAY INTO TUESDAY AS THE COLD FRONT TAKES ITS
TIME CROSSING THE REGION.

MODEL AGREEMENT BEGINS TO DIVERGE LATER INTO TUESDAY AS THE ECMWF
IS SLOWER WITH THE FRONTAL PASSAGE AND IN ADDITION SUGGESTS THE
DEVELOPMENT OF ANOTHER 500HPA CUTOFF LOW CONTINUING PRECIPITATION
CHANCES THROUGHOUT THE DAY WEDNESDAY. THE GFS MAINTAINS AN OPEN
WAVE AND THUS HAS A FASTER SOLUTION ENDING PRECIPITATION SOONER ON
WEDNESDAY. DECIDED TO REMAIN CLOSER TO THE GFS BUT KEPT SLIGHT
CHANCE POPS THROUGH WEDNESDAY DUE TO THE UNCERTAINTY.

&&

.LONG TERM /THURSDAY THROUGH SATURDAY/...
12Z GFS/00Z ECMWF HAVE DIFFERENT DEPICTIONS IN THE EXTENDED...AND
THEREFORE CONFIDENCE IS BELOW AVERAGE. BOTH MODELS SHOW GENERAL
AGREEMENT THAT THERE WILL BE A NEARLY STATIONARY UPPER LEVEL
LOW/TROUGH NEAR THE CAROLINAS. HOWEVER...MULTIPLE RUNS OF THE GFS
KEEPS THIS FEATURE OVER THE ATLANTIC OCEAN WITH JUST SOME CLOUDS
LOCALLY...WHILE THE ECMWF HAS THE FEATURE INLAND ALONG THE EAST
COAST AND SPREADS RAIN AS FAR WEST AS WEST VIRGINIA AND EASTERN
OHIO. WITH NAEFS AND ECMWF ENSEMBLE KEEPING THE PATTERN A LITTLE
DRIER...HAVE ALSO STUCK WITH A DRIER FORECAST. IF THIS HOLDS...AND
THE GFS FORECAST VERIFIES...THIS PERIOD WILL BE QUITE WARM. GFS
BIAS-CORRECTED GRIDS AND NAEFS METEOGRAMS SUGGEST THAT 90 DEGREES IS
NOT OUT OF THE QUESTION FOR THE START OF THE MEMORIAL DAY WEEKEND.

&&

.AVIATION /16Z SUNDAY THROUGH THURSDAY/...
HIGH PRESSURE WILL KEEP SKIES MOSTLY CLEAR WITH ONLY A FEW CIRRUS.
WINDS BELOW 10 KTS FOR NEXT 24 HOURS.

.OUTLOOK...MONDAY THROUGH THURSDAY...
COLD FRONT APPROACHES FROM THE WEST ON MONDAY WHILE MOISTURE
INCREASES FROM THE EAST AS LOW PRESSURE MOVES UP THE EASTERN
SEABOARD. RESTRICTIONS POSSIBLE THROUGH WEDNESDAY. PRECIPITATION
SHOULD THEN SHIFT EAST OF THE AREA BY WEDNESDAY NIGHT WITH GENERAL
VFR THURSDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$

000
FXUS61 KCTP 201440
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1040 AM EDT SUN MAY 20 2012

.SYNOPSIS...
HIGH PRESSURE WILL REMAIN OVER PENNSYLVANIA TODAY. AN UPPER LOW OVER
THE SOUTHEAST CONUS WILL LIFT NORTH ALONG THE E COAST ON MONDAY. A
DEEPENING SHORTWAVE WILL SLOW DOWN AND CUT OFF OVR THE CENTRAL
APPALACHIANS DURING MIDWEEK. PENNSYLVANIA WILL BE ON THE EDGE OF A
BUILDING 500 HPA RIDGE ACROSS THE OHIO VALLEY BY THE END OF NEXT
WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
ANOTHER BEAUTIFUL DAY ACROSS CENTRAL PA...WITH THE WARMEST HIGHS
RELATIVE TO NORMAL SHOULD BE ACROSS THE NW MTNS THANKS TO
ANOMALOUS 850 MB TEMPS ~16C. DOWNSLOPING SE FLOW SHOULD PUSH
READINGS TO THE M80S ACROSS WARREN/MCKEAN COUNTIES. WITH 850 MB
TEMPS RUNNING BETWEEN 12C AND 14C AND INCREASING EASTERLY FLOW
OFF THE COOL ATLANTIC...TEMPS SHOULD HOLD AROUND 80F ACROSS THE
NORMALLY WARMER SOUTHERN COUNTIES. MARITIME MOISTURE AND CLOUDS
FROM THE DEEPER EASTERLY FLOW SHOULD STAY TO THE EAST AND SOUTH
OVER SOUTHERN NJ...DE AND MD THROUGH THE DAYLIGHT HOURS.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/...
UPPER LOW OVER THE SOUTHEAST CONUS WILL LIFT NORTH ALONG THE E
COAST ON MONDAY. ASSOCIATED MOIST...EASTERLY LL JET AND UPPER LVL
DIVERGENCE PRECEDING THE UPPER LOW WILL LIKELY BRING SCT SHOWERS
TO CENTRAL PA BEGINNING LATE TONIGHT ACROSS THE SOUTHEAST ZONES
AND OVERSPREADING THE REST OF CENTRAL PA DURING MONDAY. CLOUD
COVER...PRECIP AND EASTERLY FLOW OFF THE ATLANTIC WILL RESULT IN A
MUCH COOLER MONDAY WITH MAX TEMPS ONLY ARND 70F. GEFS DATA SHOWING
HIGHEST PWATS ACROSS SOUTHEAST PA...WHERE THE BEST CHC OF
MEASURABLE RAINFALL IS EXPECTED SUN NITE/MONDAY.

DOWNSLOPING SE FLOW WILL RESULT IN PARTIAL SUNSHINE AND A SOMEWHAT
WARMER MONDAY OVR WARREN COUNTY...WHERE A LATE DAY TSRA IS POSSIBLE.
CAPE VALUES IN THE 600 TO 800JK-1 RANGE ACROSS WARREN CO MON
EVENING. FURTHER EAST...A COOLER MORE STABLE EASTERLY FLOW SHOULD
PRECLUDE THUNDER.

&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
OPERATIONAL AND ENSEMBLE MODEL DATA ALL INDICATE THAT AS E COAST
UPPER LOW OPENS UP AND LIFTS INTO THE CANADIAN MARITIMES...UPSTREAM
SHORTWAVE WILL DEEPEN AND CUT OFF OVR THE CENTRAL APPALACHIANS DURING
THE MIDDLE OF NEXT WEEK. ALTHOUGH MINOR MDL DIFFERENCES REMAIN WITH
RESPECT TO TIMING AND TRACK OF THIS FEATURE...ENOUGH SUPPORT IN THE
MDL DATA TO MENTION THE CHC OF DIURNALLY ENHANCED SHRA/TSRA
TUES-THURS. NEARLY ALL MDL DATA TRACKS TS ALBERTO WELL EAST OF PA
TUE NIGHT WITH NO DIRECT IMPACT ON PA.

EASTERLY FLOW MONDAY AND APPROACHING SHORT WAVE/FRONT TUESDAY
WILL LIKELY BRING 48HR RAINFALL OF BTWN 0.25 AND 1 INCH TO MUCH
OF CENTRAL/EASTERN PA BASED ON BLEND OF LATEST OPER AND ENSEMBLE
MDL QPF.

WARMER WX APPEARS VERY LIKELY TOWARD THE END OF THE WEEK WHEN ALL
MDL DATA INDICATES A BUILDING UPPER LVL RIDGE OVER THE OHIO
VALLEY. HOWEVER...PA MAY BE ON PERIPHERY OF THIS FEATURE...PLACING
AT LEAST NORTHERN PA IN RING OF FIRE WITH CHC OF PM CONVECTION.

&&

.AVIATION /14Z SUNDAY THROUGH THURSDAY/...
A RIDGE OF HIGH PRESSURE WILL REMAIN NEARLY STATIONARY OVER
PENNSYLVANIA TODAY...CONTINUING A PERIOD OF VFR CONDITIONS WITH
CLEAR SKIES AND LIGHT EASTERLY WINDS.

CLOUDS INCREASE SUNDAY NIGHT INTO MONDAY AS A DEEP LOW LIFTS INTO
THE REGION FROM THE SOUTHEAST. SHOWERY WEATHER RETURNS EARLY
MONDAY WITH MVFR TO IFR CONDITIONS IN LOW CIGS DEVELOP IN THE
LOWER SUSQ /MDT-LNS AND POSS IPT/ AFTER 06Z MON. LOWER CIGS AND
RAIN SHOWERS SPREAD FURTHER INTO CENTRAL MTNS DURING THE DAY MON.

OUTLOOK...
MON...SCATTERED MVFR /IFR SE/ CIGS AND VSBYS IN SHOWERS AND ISOLD
THUNDERSTORMS.
MON NIGHT-WED...MORE WIDESPREAD MVFR/IFR CIGS AND VSBYS LIKELY IN
SHOWERS AND SCTD TSRA.
THU...PRIMARILY VFR. SCT SHRA/TSTM POSS MAINLY SE.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...GRUMM/FITZGERALD
NEAR TERM...DEVOIR/FITZGERALD
SHORT TERM...FITZGERALD
LONG TERM...GRUMM/FITZGERALD
AVIATION...RXR

000
FXUS61 KPHI 201316
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
916 AM EDT SUN MAY 20 2012

.SYNOPSIS...
AN AREA OF LOW PRESSURE OFF THE MID-ATLANTIC COAST WILL DRIFT
WESTWARD ON LAND LATER TODAY INTO TONIGHT. MEANWHILE, TROPICAL STORM
ALBERTO WILL MEANDER OFF THE SOUTH CAROLINA COAST THROUGH MONDAY,
BEFORE MOVING NORTHEAST AND WEAKENING THROUGH WEDNESDAY. A
FRONTAL BOUNDARY IS FORECAST TO AFFECT THE AREA TUESDAY NIGHT INTO
WEDNESDAY, BEFORE SLOWLY MOVING TO OUR SOUTH THROUGH THURSDAY. HIGH
PRESSURE MAY THEN BUILD ACROSS THE AREA FROM THE NORTHEAST FRIDAY
INTO SATURDAY, WITH THE POSSIBILITY OF A COLD FRONT LATE SATURDAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MADE A FEW ADJUSTMENTS TO CLOUD COVER BASED ON LATEST SATELLITE
IMAGERY. ALSO ADJUSTED TEMPS WHERE NECESSARY. OTHERWISE PREVIOUS
FCST RATIONALE STILL LOOKED GOOD.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...
TONIGHT...A CONDUIT OF MOISTURE IN DEEP SE FLOW SHOULD NOT ONLY
DEVELOP SHOWERS ACROSS MOST OF THE AREA DURING THE NIGHT
/INSTABILITY BURST/ BUT 0.25 TO AS MUCH AS ISOLATED 1 INCH AMTS
ARE FCST BY 12Z MONDAY IN NJ/DE WITH LESSER AMTS IN PA/MD.

ISO THUNDER IS POSSIBLE IN COASTAL NJ/DE AFTER 05Z WITH INSTABILITY
ALOFT...VIA A SWI SUBZERO...SOME CAPE ON THE SE SIDE OF THE INVERTED
TROUGH /SE BL WIND/. THE PROB FOR THUNDER IS LOW ENOUGH NOT TO BE
IN THE LEGACY ZONES BUT DOES SHOW UP IN THE MORE DETAILED
POINT/CLICK INFORMATION.

BLENDED NCEP STATISTICAL GUIDANCE FOR WINDS/TEMPS.

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...
BROAD TROUGHING ALOFT WILL REMAIN ACROSS THE EAST COAST FOR MUCH OF
THE WEEK, WHICH WILL KEEP UNSETTLED WEATHER FOR MUCH OF THE EXTENDED
FORECAST. ON MONDAY, THE SURFACE LOW THAT MOVED INLAND TO OUR SOUTH
WILL WEAKEN, BUT AN ABUNDANCE OF MOISTURE WILL CONTINUE TO FLOW IN
ACROSS THE AREA. PWAT VALUES REACH 1.5-1.75 INCHES DURING THE DAY
MONDAY, SO THERE COULD BE A PERIOD OF MODERATE TO HEAVY RAIN ACROSS
THE AREA. THERE IS SOME INSTABILITY IN THE ATMOSPHERE, SO WE HAVE
ADDED A CHANCE OF THUNDERSTORMS.

A FRONTAL BOUNDARY IS EXPECTED TO APPROACH THE AREA TUESDAY, BEFORE
SETTLING ACROSS THE AREA TUESDAY NIGHT INTO WEDNESDAY. WITH THE
BROAD TROUGH ALOFT, SEVERAL VORT MAXES/SHORT WAVES WILL LIKELY CROSS
THE AREA DURING THIS TIME PERIOD. THEREFORE WE WILL KEEP A CHANCE OF
SHOWERS IN THE FORECAST, AND CONTINUE A CHANCE OF THUNDERSTORMS
SINCE THERE IS SOME INSTABILITY ACROSS THE AREA.

BY THURSDAY, THE FRONT SHOULD SINK TO OUR SOUTH, BUT FOR THURSDAY
THROUGH THE END OF THE WEEK, THE TROUGH ALOFT WILL BE SLOW TO PULL
OUT OF THE AREA. THIS WILL KEEP A SLIGHT CHANCE OF
SHOWERS/THUNDERSTORMS ACROSS THE AREA. THE SHOWER ACTIVITY WOULD
MOST LIKELY OCCUR DURING EACH AFTERNOON DUE TO THE DAYTIME HEATING.

THE NHC HAS NAMED TROPICAL STORM ALBERTO WHICH IS LOCATED OFF THE
SOUTH CAROLINA COAST. THE LATEST TRACK HAS THE STORM MEANDERING OFF
THE SOUTH CAROLINA COAST THROUGH MONDAY, THEN MOVING NORTHEAST AND
WEAKENING THROUGH WEDNESDAY. THE CURRENT TRACK KEEPS THE STORM AWAY
FROM OUR AREA, BUT WE WILL HAVE TO CONTINUE TO MONITOR THE FORECAST
IN CASE THE TRACK MOVES FURTHER WEST. VISIT THE NHC`S WEBSITE FOR
MORE INFORMATION ON THE TROPICAL STORM ALBERTO.

&&

.AVIATION /13Z SUNDAY THROUGH THURSDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.

THROUGH 12Z...VFR MOSTLY CLEAR WITH JUST SOME CIRRUS AROUND.
LIGHT NE WIND.

AFTER 12Z...VFR. MVFR CIGS MOVE WESTWARD ASHORE BETWEEN 16Z-19Z
FM VCNTY KACY TO KGED AND SPREAD NWWD THIS AFTN COVERING MOST OF
SE NJ AND MOST OF DE BY 00Z/21. NE WIND GUSTS 20-25 KTS BY NOON.
SCT SHOWERS DEVELOP VCNTY KACY THRU MOST OF S DE SOMETIME DURING
THE AFTN. FOR NOW THE FCST IN THE TAFS IS NEAR 00Z BUT SUBJECT TO
CHANGE BASED ON RADAR.

TONIGHT...MVFR CIGS SPREAD OVER ALL THE REGION DURING THE NIGHT AND
SHOWERS BECOME MORE WIDESPREAD. SHOWERS WILL BE BRIEFLY HEAVY IN
NJ/DE. ITS ALSO LIKELY THAT IFR CONDS DEVELOP IN SOME OF THE SHOWERS
AS WELL AS ST/FOG...MAINLY AFTER 05Z/21.


OUTLOOK...
MONDAY/MONDAY NIGHT...MVFR/IFR CIGS/VSBYS EXPECTED, ESPECIALLY WITH
SHOWERS. MOSTLY EAST/NORTHEAST WINDS AROUND 10-15 KNOTS.

TUESDAY/TUESDAY NIGHT...MVFR/IFR EARLY, POSSIBLY IMPROVING TO VFR BY
AFTERNOON EXCEPT IN SHOWERS/THUNDERSTORMS. EAST WINDS BECOMING
SOUTHEAST DURING THE DAY. MVFR/IFR CIGS/VSBYS POSSIBLE AT NIGHT.

WEDNESDAY/WEDNESDAY NIGHT...MOSTLY VFR, POSSIBLE MVFR IN
SHOWERS/THUNDERSTORMS DURING THE AFTERNOON. EAST/SOUTHEAST WINDS
5-10 KNOTS. MVFR/IFR CIGS/VSBYS POSSIBLE AT NIGHT.

THURSDAY...MVFR/IFR POSSIBLE EARLY, IMPROVING TO VFR BY AFTERNOON
EXCEPT IN SHOWERS/THUNDERSTORMS. SOUTHEAST WINDS AROUND 5-10 KNOTS.

&&

.MARINE...
TODAY AND TONIGHT...SCA CONTINUES AS POSTED. THE HAZARDOUS SEAS
HAVE BEEN IN PROGRESS OVER VIRTUALLY ALL THE ATLC WATERS FOR A DAY
NOW...THE EXCEPTION POSSIBLY IN PORTIONS OF ANZ450. ONSHORE WINDS
ARE MODELED TO INCREASE 5 TO 10 KTS TODAY THROUGHOUT THE WATERS
/HIGHER THAN YDY/ BEFORE WINDS SUBSIDE LATER TONIGHT. IF THE WIND
FCST IS CORRECT...SEAS TO 10 FEET WILL DEVELOP FOR THE DE COAST
TODAY. WE ADDED DE BAY TO SCA TODAY PER THE MODELED WIND INCREASE.

OUTLOOK...
THE SMALL CRAFT ADVISORY WILL REMAIN THROUGH MONDAY AS WAVEWATCH
GUIDANCE KEEPS SEAS ABOVE 5 FEET THROUGH THE TIME PERIOD. WE WILL
NEED TO CONTINUE TO MONITOR THE FORECAST TRACK FOR TROPICAL STORM
ALBERTO TO SEE IF ANY STRONG WINDS WILL MAKE IT ACROSS OUR WATERS.
THE LATEST TRACK FROM THE NHC KEEPS THE STORM FAR ENOUGH AWAY FROM
OUR WATERS TO NOT GET STORM FORCE WINDS. HOWEVER, SEAS MAY REMAIN
ELEVATED THROUGH WEDNESDAY, WHICH IS WHEN THE STORM IS EXPECTED TO
PASS TO OUR EAST.

&&

.FIRE WEATHER...
WE`LL CHECK WITH FORESTRY OFFICIALS AFTER 8AM TODAY TO SEE
WHETHER THEY PREFER AN SPS FOR THE 2P-5P PERIOD THIS AFTERNOON
FROM THE LEHIGH VALLEY INTO NW NJ WHEN RH IS BELOW 30 PCT...NE
WINDS WILL BE GUSTING TO 20 MPH...10 HR FUELS ARE IN THE 6 TO 9
PCT RANGE AFTER 4 SUCCESSIVE DRY DAYS.

&&

.TIDES/COASTAL FLOODING...
WITH A CONTINUED NORTHEAST TO EAST FLOW TONIGHT AND MONDAY, THERE
REMAINS THE POTENTIAL FOR SPOTTY MINOR TIDAL FLOODING...MAINLY THE
DELAWARE WATERS.

POSITIVE DEPARTURES AROUND A FOOT AND A QUARTER ARE NEEDED TO
REACH THE MINOR FLOODING THRESHOLD. WE WILL CONTINUE TO MONITOR
THE TRENDS ALONG WITH THE LATEST GUIDANCE.

00Z/20 MRPSSE GUIDANCE WILL BE AT LEAST HALF A FOOT TOO LOW FOR
TONIGHTS-SUNDAY NIGHT UPCOMING HIGH TIDE. SO FAR NO GUIDANCE
EXCEEDS THE THRESHOLD.

THINK WE WILL EVENTUALLY NEED A CF STATEMENT FOR TIDES NUDGING
MINOR FS OR JUST BLO BY 0.2 FT FOR THE TIDAL DELAWARE AS WELL AS
DE ATLC COAST THIS COMING SUNDAY NIGHT HIGH TIDE CYCLE.

BASICALLY THIS FOCUSES ON LEWES/REEDY/PHL.

NO ACTION ON THIS SHIFT DUE TO UNCERTAINTY AS WELL AS ONLY
"APPROACHING" THRESHOLD INSTEAD OF ANY CLEAR GUIDANCE EXCEEDING
THRESHOLD. PREDICTION FOR TONIGHT AT LEWES AT LEAST 5.7 AS PER OUR
LOCAL STATISTICAL PROGRAM.

&&

.RIP CURRENTS...
THE COMBINATION OF A 4 TO 6 FOOT EAST TO SOUTHEAST SWELL WITH AN 8
TO 10 SECOND PERIOD AND 1 TO 4 FEET OF WIND WAVES ON TOP OF THAT...
GENERATED BY AN INCREASING NORTHEAST WIND OF 20 TO OCCASIONALLY
25 KNOTS...PRODUCES AN ENVIRONMENT THAT RAISES THE RISK OF
RIP CURRENTS INTO THE HIGH LIKELIHOOD CATEGORY.

WE KNOW WATER TEMPERATURES ARE COLD FOR MOST RECREATIONAL BATHERS...
GENERALLY BETWEEN 55 AND 60 DEGREES...AND SO THERE ARE PROBABLY
FEW SWIMMERS. HOWEVER...IN THE INTEREST OF PROTECTION OF LIFE...
AND SINCE OUR SURF ZONE FORECAST HAS STARTED THIS SEASON...THE
HEADLINE INFORMATION HAS BEEN ISSUED.

DIMINISHING WIND AND SEAS ON MONDAY-TOMORROW SHOULD LOWER THE RISK TO
MODERATE.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...HIGH RIP CURRENT RISK THROUGH THIS EVENING FOR NJZ014-024>026.
DE...HIGH RIP CURRENT RISK THROUGH THIS EVENING FOR DEZ004.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT MONDAY FOR ANZ452>455.
     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 PM EDT MONDAY
     FOR ANZ450-451.
     SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR ANZ430-
     431.

&&

$$
SYNOPSIS...ROBERTSON
NEAR TERM...DRAG/NIERENBERG
SHORT TERM...DRAG
LONG TERM...ROBERTSON
AVIATION...DRAG/ROBERTSON
MARINE...DRAG/ROBERTSON
FIRE WEATHER...DRAG
TIDES/COASTAL FLOODING...DRAG
RIP CURRENTS...DRAG

000
FXUS61 KPBZ 201210
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
810 AM EDT SUN MAY 20 2012

.SYNOPSIS...
HIGH PRESSURE WILL ALLOW FOR DRY AND UNSEASONABLY WARM WEATHER TO
CONTINUE INTO EARLY MONDAY. THE CHANCE OF SHOWERS AND THUNDERSTORMS
WILL RETURN AS A LOW PULLS MOISTURE INTO THE AREA FROM THE SOUTHEAST
AND A FRONTAL BOUNDARY APPROACHES FROM THE WEST.

&&

.NEAR TERM /THROUGH TONIGHT/...
WITH 8AM UPDATE...ONLY MINOR TWEAKS WERE MADE TO HOURLY
SKY/TEMPERATURE TRENDS. PREVIOUS DISCUSSION FOLLOWS.

MID-LEVEL RIDGE WILL CONTINUE ITS HOLD OVER THE REGION FOR ONE
MORE PLEASANT DAY BEFORE PRECIPITATION CHANCES AND TEMPERATURES
CLOSER TO NORMAL RETURN. SOME CIRRUS ASSOCIATED WITH TS ALBERTO
WILL SPREAD OVERHEAD TODAY BUT DRY AIR IN THE LOWER LEVELS SHOULD
PREVENT CUMULUS DEVELOPMENT TODAY.

THE RIDGE WILL RIDE NORTH OVER THE UPPER LEVEL CUTOFF LOW OF BOTH
ALBERTO AND A LOW SITUATED TO ITS NORTHEAST...BEST DEPICTED ON IR
SATELLITE. A MORE SOUTHERLY WIND COMPONENT ALOFT AND GENERALLY
CLEAR SKIES SHOULD ALLOW FOR TEMPERATURES TO REBOUND TO WELL ABOVE
NORMAL ONCE AGAIN AS 850HPA TEMPS EXCEED +16C. HEDGED CLOSEST TO
MAV GUIDANCE THOUGH IT`S NOT UNREASONABLE THAT TEMPERATURES COULD
MAKE IT A DEGREE OR TWO WARMER THAN CURRENT FORECAST. OPTED TO GO
WITH A PERSISTENCE TEMPERATURE FORECAST.

&&

.SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/...
THE GFS/ECMWF/UKMET CONTINUE TO SUGGEST THAT AS THE RIDGE
TRANSFERS TOWARDS THE COAST...THE CUTOFF LOW WILL RETROGRADE
HELPING TO BRING MOISTURE TOWARDS THE NORTHEAST AND OHIO VALLEY
MONDAY. THUS...CONTINUED TO CARRY SLIGHT CHANCE POPS STARTING
MONDAY MORNING IN THE RIDGES AND INCREASING AS THE DAY PROGRESSES
AND LOWER LEVELS MOISTEN. IN ADDITION...THE UPPER LEVEL TROUGH
OVER THE MIDWEST WILL MAKE ITS APPROACH LATER MONDAY AFTERNOON AND
WITH IT MODELS MAINTAIN ENOUGH INSTABILITY FOR THUNDERSTORM
DEVELOPMENT LATER MONDAY INTO TUESDAY AS THE COLD FRONT TAKES ITS
TIME CROSSING THE REGION.

MODEL AGREEMENT BEGINS TO DIVERGE LATER INTO TUESDAY AS THE ECMWF
IS SLOWER WITH THE FRONTAL PASSAGE AND IN ADDITION SUGGESTS THE
DEVELOPMENT OF ANOTHER 500HPA CUTOFF LOW CONTINUING PRECIPITATION
CHANCES THROUGHOUT THE DAY WEDNESDAY. THE GFS MAINTAINS AN OPEN
WAVE AND THUS HAS A FASTER SOLUTION ENDING PRECIPITATION SOONER ON
WEDNESDAY. DECIDED TO REMAIN CLOSER TO THE GFS BUT KEPT SLIGHT
CHANCE POPS THROUGH WEDNESDAY DUE TO THE UNCERTAINTY.

&&

.LONG TERM /THURSDAY THROUGH SATURDAY/...
12Z GFS/00Z ECMWF HAVE DIFFERENT DEPICTIONS IN THE EXTENDED...AND
THEREFORE CONFIDENCE IS BELOW AVERAGE. BOTH MODELS SHOW GENERAL
AGREEMENT THAT THERE WILL BE A NEARLY STATIONARY UPPER LEVEL
LOW/TROUGH NEAR THE CAROLINAS. HOWEVER...MULTIPLE RUNS OF THE GFS
KEEPS THIS FEATURE OVER THE ATLANTIC OCEAN WITH JUST SOME CLOUDS
LOCALLY...WHILE THE ECMWF HAS THE FEATURE INLAND ALONG THE EAST
COAST AND SPREADS RAIN AS FAR WEST AS WEST VIRGINIA AND EASTERN
OHIO. WITH NAEFS AND ECMWF ENSEMBLE KEEPING THE PATTERN A LITTLE
DRIER...HAVE ALSO STUCK WITH A DRIER FORECAST. IF THIS HOLDS...AND
THE GFS FORECAST VERIFIES...THIS PERIOD WILL BE QUITE WARM. GFS
BIAS-CORRECTED GRIDS AND NAEFS METEOGRAMS SUGGEST THAT 90 DEGREES IS
NOT OUT OF THE QUESTION FOR THE START OF THE MEMORIAL DAY WEEKEND.

&&

.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
HIGH PRESSURE WILL KEEP SKIES MOSTLY CLEAR WITH ONLY A FEW CIRRUS.
WINDS BELOW 10 KTS FOR NEXT 24 HOURS.

.OUTLOOK...MONDAY THROUGH THURSDAY...
COLD FRONT APPROACHES FROM THE WEST ON MONDAY WHILE MOISTURE
INCREASES FROM THE EAST AS LOW PRESSURE MOVES UP THE EASTERN
SEABOARD. RESTRICTIONS POSSIBLE THROUGH WEDNESDAY. PRECIPITATION
SHOULD THEN SHIFT EAST OF THE AREA BY WEDNESDAY NIGHT WITH GENERAL
VFR THURSDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$

000
FXUS61 KCTP 201149
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
749 AM EDT SUN MAY 20 2012

.SYNOPSIS...
HIGH PRESSURE WILL REMAIN OVER PENNSYLVANIA TODAY. AN UPPER LOW OVER
THE SOUTHEAST CONUS WILL LIFT NORTH ALONG THE E COAST ON MONDAY. A
DEEPENING SHORTWAVE WILL SLOW DOWN AND CUT OFF OVR THE CENTRAL
APPALACHIANS DURING MIDWEEK. PENNSYLVANIA WILL BE ON THE EDGE OF A
BUILDING 500 HPA RIDGE ACROSS THE OHIO VALLEY BY THE END OF NEXT
WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SINKING AIR ASSOCIATED WITH HIGH PRES AT SFC AND ALOFT WILL
PROVIDE PA WITH ANOTHER SUNNY AND WARM DAY. AIR MASS CONTINUES TO
WARM...BEING WORKED ON BY STRONG LATE SPRING SUNSHINE. THE
WARMEST HIGHS RELATIVE TO NORMAL SHOULD BE ACROSS THE NW
MTNS...WHERE DOWNSLOPING SE FLOW SHOULD PUSH READINGS TO THE M80S
ACROSS WARREN/MCKEAN COUNTIES. INCREASING EASTERLY FLOW OFF THE
COOL ATLANTIC WILL HOLD TEMPS TO ARND 80F ACROSS THE NORMALLY
WARMER SOUTHERN COUNTIES.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/...
UPPER LOW OVER THE SOUTHEAST CONUS WILL LIFT NORTH ALONG THE E
COAST ON MONDAY. ASSOCIATED MOIST...EASTERLY LL JET AND UPPER LVL
DIVERGENCE PRECEDING THE UPPER LOW WILL LIKELY BRING SCT SHOWERS
TO CENTRAL PA BEGINNING LATE TONIGHT ACROSS THE SOUTHEAST ZONES
AND OVERSPREADING THE REST OF CENTRAL PA DURING MONDAY. CLOUD
COVER...PRECIP AND EASTERLY FLOW OFF THE ATLANTIC WILL RESULT IN A
MUCH COOLER MONDAY WITH MAX TEMPS ONLY ARND 70F. GEFS DATA SHOWING
HIGHEST PWATS ACROSS SOUTHEAST PA...WHERE THE BEST CHC OF
MEASURABLE RAINFALL IS EXPECTED SUN NITE/MONDAY.

DOWNSLOPING SE FLOW WILL RESULT IN PARTIAL SUNSHINE AND A SOMEWHAT
WARMER MONDAY OVR WARREN COUNTY...WHERE A LATE DAY TSRA IS POSSIBLE.
CAPE VALUES IN THE 600 TO 800JK-1 RANGE ACROSS WARREN CO MON
EVENING. FURTHER EAST...A COOLER MORE STABLE EASTERLY FLOW SHOULD
PRECLUDE THUNDER.

&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
OPERATIONAL AND ENSEMBLE MODEL DATA ALL INDICATE THAT AS E COAST
UPPER LOW OPENS UP AND LIFTS INTO THE CANADIAN MARITIMES...UPSTREAM
SHORTWAVE WILL DEEPEN AND CUT OFF OVR THE CENTRAL APPALACHIANS DURING
THE MIDDLE OF NEXT WEEK. ALTHOUGH MINOR MDL DIFFERENCES REMAIN WITH
RESPECT TO TIMING AND TRACK OF THIS FEATURE...ENOUGH SUPPORT IN THE
MDL DATA TO MENTION THE CHC OF DIURNALLY ENHANCED SHRA/TSRA
TUES-THURS. NEARLY ALL MDL DATA TRACKS TS ALBERTO WELL EAST OF PA
TUE NIGHT WITH NO DIRECT IMPACT ON PA.

EASTERLY FLOW MONDAY AND APPROACHING SHORT WAVE/FRONT TUESDAY
WILL LIKELY BRING 48HR RAINFALL OF BTWN 0.25 AND 1 INCH TO MUCH
OF CENTRAL/EASTERN PA BASED ON BLEND OF LATEST OPER AND ENSEMBLE
MDL QPF.

WARMER WX APPEARS VERY LIKELY TOWARD THE END OF THE WEEK WHEN ALL
MDL DATA INDICATES A BUILDING UPPER LVL RIDGE OVER THE OHIO
VALLEY. HOWEVER...PA MAY BE ON PERIPHERY OF THIS FEATURE...PLACING
AT LEAST NORTHERN PA IN RING OF FIRE WITH CHC OF PM CONVECTION.

&&

.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
A RIDGE OF HIGH PRESSURE WILL REMAIN NEARLY STATIONARY OVER
PENNSYLVANIA TODAY...CONTINUING A PERIOD OF VFR CONDITIONS WITH
CLEAR SKIES AND LIGHT EASTERLY WINDS.

CLOUDS INCREASE SUNDAY NIGHT INTO MONDAY AS A DEEP LOW LIFTS INTO
THE REGION FROM THE SOUTHEAST. SHOWERY WEATHER RETURNS EARLY
MONDAY WITH MVFR TO IFR CONDITIONS IN LOW CIGS DEVELOP IN THE
LOWER SUSQ /MDT-LNS AND POSS IPT/ AFTER 06Z MON. LOWER CIGS AND
RAIN SHOWERS SPREAD FURTHER INTO CENTRAL MTNS DURING THE DAY MON.

OUTLOOK...
MON...SCATTERED MVFR /IFR SE/ CIGS AND VSBYS IN SHOWERS AND ISOLD
THUNDERSTORMS.
MON NIGHT-WED...MORE WIDESPREAD MVFR/IFR CIGS AND VSBYS LIKELY IN
SHOWERS AND SCTD TSRA.
THU...PRIMARILY VFR. SCT SHRA/TSTM POSS MAINLY SE.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...GRUMM/FITZGERALD
NEAR TERM...FITZGERALD
SHORT TERM...FITZGERALD
LONG TERM...GRUMM/FITZGERALD
AVIATION...RXR

000
FXUS61 KCTP 201123
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
615 AM EDT SUN MAY 20 2012

.SYNOPSIS...
HIGH PRESSURE WILL REMAIN OVER PENNSYLVANIA TODAY. AN UPPER LOW OVER
THE SOUTHEAST CONUS WILL LIFT NORTH ALONG THE E COAST ON MONDAY. A
DEEPENING SHORTWAVE WILL SLOW DOWN AND CUT OFF OVR THE CENTRAL
APPALACHIANS DURING MIDWEEK. PENNSYLVANIA WILL BE ON THE EDGE OF A
BUILDING 500 HPA RIDGE ACROSS THE OHIO VALLEY BY THE END OF NEXT
WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SINKING AIR ASSOCIATED WITH HIGH PRES AT SFC AND ALOFT WILL
PROVIDE PA WITH ANOTHER SUNNY AND WARM DAY. AIR MASS CONTINUES TO
WARM...BEING WORKED ON BY STRONG LATE SPRING SUNSHINE. THE
WARMEST HIGHS RELATIVE TO NORMAL SHOULD BE ACROSS THE NW
MTNS...WHERE DOWNSLOPING SE FLOW SHOULD PUSH READINGS TO THE M80S
ACROSS WARREN/MCKEAN COUNTIES. INCREASING EASTERLY FLOW OFF THE
COOL ATLANTIC WILL HOLD TEMPS TO ARND 80F ACROSS THE NORMALLY
WARMER SOUTHERN COUNTIES.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/...
UPPER LOW OVER THE SOUTHEAST CONUS WILL LIFT NORTH ALONG THE E
COAST ON MONDAY. ASSOCIATED MOIST...EASTERLY LL JET AND UPPER LVL
DIVERGENCE PRECEDING THE UPPER LOW WILL LIKELY BRING SCT SHOWERS
TO CENTRAL PA BEGINNING LATE TONIGHT ACROSS THE SOUTHEAST ZONES
AND OVERSPREADING THE REST OF CENTRAL PA DURING MONDAY. CLOUD
COVER...PRECIP AND EASTERLY FLOW OFF THE ATLANTIC WILL RESULT IN A
MUCH COOLER MONDAY WITH MAX TEMPS ONLY ARND 70F. GEFS DATA SHOWING
HIGHEST PWATS ACROSS SOUTHEAST PA...WHERE THE BEST CHC OF
MEASURABLE RAINFALL IS EXPECTED SUN NITE/MONDAY.

DOWNSLOPING SE FLOW WILL RESULT IN PARTIAL SUNSHINE AND A SOMEWHAT
WARMER MONDAY OVR WARREN COUNTY...WHERE A LATE DAY TSRA IS POSSIBLE.
CAPE VALUES IN THE 600 TO 800JK-1 RANGE ACROSS WARREN CO MON
EVENING. FURTHER EAST...A COOLER MORE STABLE EASTERLY FLOW SHOULD
PRECLUDE THUNDER.

&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
OPERATIONAL AND ENSEMBLE MODEL DATA ALL INDICATE THAT AS E COAST
UPPER LOW OPENS UP AND LIFTS INTO THE CANADIAN MARITIMES...UPSTREAM
SHORTWAVE WILL DEEPEN AND CUT OFF OVR THE CENTRAL APPALACHIANS DURING
THE MIDDLE OF NEXT WEEK. ALTHOUGH MINOR MDL DIFFERENCES REMAIN WITH
RESPECT TO TIMING AND TRACK OF THIS FEATURE...ENOUGH SUPPORT IN THE
MDL DATA TO MENTION THE CHC OF DIURNALLY ENHANCED SHRA/TSRA
TUES-THURS. NEARLY ALL MDL DATA TRACKS TS ALBERTO WELL EAST OF PA
TUE NIGHT WITH NO DIRECT IMPACT ON PA.

EASTERLY FLOW MONDAY AND APPROACHING SHORT WAVE/FRONT TUESDAY
WILL LIKELY BRING 48HR RAINFALL OF BTWN 0.25 AND 1 INCH TO MUCH
OF CENTRAL/EASTERN PA BASED ON BLEND OF LATEST OPER AND ENSEMBLE
MDL QPF.

WARMER WX APPEARS VERY LIKELY TOWARD THE END OF THE WEEK WHEN ALL
MDL DATA INDICATES A BUILDING UPPER LVL RIDGE OVER THE OHIO
VALLEY. HOWEVER...PA MAY BE ON PERIPHERY OF THIS FEATURE...PLACING
AT LEAST NORTHERN PA IN RING OF FIRE WITH CHC OF PM CONVECTION.

&&

.AVIATION /10Z SUNDAY THROUGH THURSDAY/...
A RIDGE OF HIGH PRESSURE WILL REMAIN NEARLY STATIONARY OVER
PENNSYLVANIA THROUGH SUNDAY...CONTINUING A PERIOD OF VFR
CONDITIONS WITH CLEAR SKIES AND LIGHT WINDS.

EASTERLY FLOW BEGINS TO INCREASE ACROSS THE REGION ON SUNDAY.
CLOUDS INCREASE SUNDAY NIGHT INTO MONDAY AS A DEEP LOW BACKS INTO
THE REGION FROM THE SOUTHEAST. SHOWERY WEATHER RETURNS EARLY
MONDAY WITH MVFR TO IFR CONDITIONS IN LOW CIGS AND VSBY POSSIBLE
IN RAIN SHOWERS ALONG THE LOWER SUSQ TAF SITES /MDT-LNS AND POSS
IPT/.

OUTLOOK...
SUN...VFR WITH A LIGHT...MAINLY EASTERLY WIND.
MON...SCATTERED MVFR CIGS AND VSBYS IN SHOWERS AND ISOLD
THUNDERSTORMS.
MON NIGHT THROUGH WEDNESDAY...MORE WIDESPREAD
REDUCED CIGS AND VSBYS LIKELY IN SHOWERS AND SCTD TSRA.
THU...PRIMARILY VFR. SCT SHRA/TSTM POSS MAINLY SE.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...GRUMM/FITZGERALD
NEAR TERM...FITZGERALD
SHORT TERM...FITZGERALD
LONG TERM...GRUMM/FITZGERALD
AVIATION...RXR

000
FXUS61 KCTP 201015
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
615 AM EDT SUN MAY 20 2012

.SYNOPSIS...
A STRONG 500 HPA RIDGE AND WEAK SURFACE RIDGE WILL REMAIN OVER
PENNSYLVANIA TODAY. AN UPPER LOW OVER THE SOUTHEAST CONUS WILL
LIFT NORTH ALONG THE E COAST ON MONDAY. A DEEPENING SHORTWAVE WILL
SLOW DOWN AND CUT OFF OVR THE CENTRAL APPALACHIANS DURING MIDWEEK.
PENNSYLVANIA WILL BE ON THE EDGE OF A BUILDING 500 HPA RIDGE
ACROSS THE OHIO VALLEY BY THE END OF NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SINKING AIR ASSOCIATED WITH HIGH PRES AT SFC AND ALOFT WILL
PROVIDE PA WITH ANOTHER SUNNY AND WARM DAY. AIR MASS CONTINUES TO
WARM...BEING WORKED ON BY STRONG LATE SPRING SUNSHINE. THE
WARMEST HIGHS RELATIVE TO NORMAL SHOULD BE ACROSS THE NW
MTNS...WHERE DOWNSLOPING SE FLOW SHOULD PUSH READINGS TO THE M80S
ACROSS WARREN/MCKEAN COUNTIES. INCREASING EASTERLY FLOW OFF THE
COOL ATLANTIC WILL HOLD TEMPS TO ARND 80F ACROSS THE NORMALLY
WARMER SOUTHERN COUNTIES.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/...
UPPER LOW OVER THE SOUTHEAST CONUS WILL LIFT NORTH ALONG THE E
COAST ON MONDAY. ASSOCIATED MOIST...EASTERLY LL JET AND UPPER LVL
DIVERGENCE PRECEDING THE UPPER LOW WILL LIKELY BRING SCT SHOWERS
TO CENTRAL PA BEGINNING LATE TONIGHT ACROSS THE SOUTHEAST ZONES
AND OVERSPREADING THE REST OF CENTRAL PA DURING MONDAY. CLOUD
COVER...PRECIP AND EASTERLY FLOW OFF THE ATLANTIC WILL RESULT IN A
MUCH COOLER MONDAY WITH MAX TEMPS ONLY ARND 70F. GEFS DATA SHOWING
HIGHEST PWATS ACROSS SOUTHEAST PA...WHERE THE BEST CHC OF
MEASURABLE RAINFALL IS EXPECTED SUN NITE/MONDAY.

DOWNSLOPING SE FLOW WILL RESULT IN PARTIAL SUNSHINE AND A SOMEWHAT
WARMER MONDAY OVR WARREN COUNTY...WHERE A LATE DAY TSRA IS POSSIBLE.
CAPE VALUES IN THE 600 TO 800JK-1 RANGE ACROSS WARREN CO MON
EVENING. FURTHER EAST...A COOLER MORE STABLE EASTERLY FLOW SHOULD
PRECLUDE THUNDER.

&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
OPERATIONAL AND ENSEMBLE MODEL DATA ALL INDICATE THAT AS E COAST UPPER
LOW OPENS UP AND LIFTS INTO THE CANADIAN MARITIMES...UPSTREAM
SHORTWAVE WILL DEEPEN AND CUT OFF OVR THE CENTRAL APPALACHIANS DURING
THE MIDDLE OF NEXT WEEK. ALTHOUGH MINOR MDL DIFFERENCES REMAIN
WITH RESPECT TO TIMING AND TRACK OF THIS FEATURE...ENOUGH SUPPORT
IN THE MDL DATA TO MENTION THE CHC OF DIURNALLY ENHANCED SHRA/TSRA
TUES-THURS. NEARLY ALL MDL DATA TRACKS TS ALBERTO WELL EAST OF PA
TUE NIGHT WITH NO DIRECT IMPACT ON PA.

EASTERLY FLOW MONDAY AND APPROACHING SHORT WAVE/FRONT TUESDAY
WILL LIKELY BRING 48HR RAINFALL OF BTWN 0.25 AND 1 INCH TO MUCH
OF CENTRAL/EASTERN PA BASED ON BLEND OF LATEST OPER AND ENSEMBLE
MDL QPF.

WARMER WX APPEARS VERY LIKELY TOWARD THE END OF THE WEEK WHEN ALL
MDL DATA INDICATES A BUILDING UPPER LVL RIDGE OVER THE OHIO
VALLEY. HOWEVER...PA MAY BE ON PERIPHERY OF THIS FEATURE...PLACING
AT LEAST NORTHERN PA IN RING OF FIRE WITH CHC OF PM CONVECTION.

&&

.AVIATION /10Z SUNDAY THROUGH THURSDAY/...
A RIDGE OF HIGH PRESSURE WILL REMAIN NEARLY STATIONARY OVER
PENNSYLVANIA THROUGH SUNDAY...CONTINUING A PERIOD OF VFR
CONDITIONS WITH CLEAR SKIES AND LIGHT WINDS.

EASTERLY FLOW BEGINS TO INCREASE ACROSS THE REGION ON SUNDAY.
CLOUDS INCREASE SUNDAY NIGHT INTO MONDAY AS A DEEP LOW BACKS INTO
THE REGION FROM THE SOUTHEAST. SHOWERY WEATHER RETURNS EARLY
MONDAY WITH MVFR TO IFR CONDITIONS IN LOW CIGS AND VSBY POSSIBLE
IN RAIN SHOWERS ALONG THE LOWER SUSQ TAF SITES /MDT-LNS AND POSS
IPT/.

OUTLOOK...
SUN...VFR WITH A LIGHT...MAINLY EASTERLY WIND.
MON...SCATTERED MVFR CIGS AND VSBYS IN SHOWERS AND ISOLD
THUNDERSTORMS.
MON NIGHT THROUGH WEDNESDAY...MORE WIDESPREAD
REDUCED CIGS AND VSBYS LIKELY IN SHOWERS AND SCTD TSRA.
THU...PRIMARILY VFR. SCT SHRA/TSTM POSS MAINLY SE.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...GRUMM/FITZGERALD
NEAR TERM...FITZGERALD
SHORT TERM...FITZGERALD
LONG TERM...GRUMM/FITZGERALD
AVIATION...RXR

000
FXUS61 KPBZ 200924
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
524 AM EDT SUN MAY 20 2012

.SYNOPSIS...
HIGH PRESSURE WILL ALLOW FOR DRY AND UNSEASONABLY WARM WEATHER TO
CONTINUE INTO EARLY MONDAY. THE CHANCE OF SHOWERS AND THUNDERSTORMS
WILL RETURN AS A LOW PULLS MOISTURE INTO THE AREA FROM THE SOUTHEAST
AND A FRONTAL BOUNDARY APPROACHES FROM THE WEST.

&&

.NEAR TERM /THROUGH TONIGHT/...
MID-LEVEL RIDGE WILL CONTINUE ITS HOLD OVER THE REGION FOR ONE
MORE PLEASANT DAY BEFORE PRECIPITATION CHANCES AND TEMPERATURES
CLOSER TO NORMAL RETURN. SOME CIRRUS ASSOCIATED WITH TS ALBERTO
WILL SPREAD OVERHEAD TODAY BUT DRY AIR IN THE LOWER LEVELS SHOULD
PREVENT CUMULUS DEVELOPMENT TODAY.

THE RIDGE WILL RIDE NORTH OVER THE UPPER LEVEL CUTOFF LOW OF BOTH
ALBERTO AND A LOW SITUATED TO ITS NORTHEAST...BEST DEPICTED ON IR
SATELLITE. A MORE SOUTHERLY WIND COMPONENT ALOFT AND GENERALLY
CLEAR SKIES SHOULD ALLOW FOR TEMPERATURES TO REBOUND TO WELL ABOVE
NORMAL ONCE AGAIN AS 850HPA TEMPS EXCEED +16C. HEDGED CLOSEST TO MAV
GUIDANCE THOUGH IT`S NOT UNREASONABLE THAT TEMPERATURES COULD MAKE
IT A DEGREE OR TWO WARMER THAN CURRENT FORECAST. OPTED TO GO WITH
A PERSISTENCE TEMPERATURE FORECAST.

&&

.SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/...
THE GFS/ECMWF/UKMET CONTINUE TO SUGGEST THAT THE AS THE RIDGE
TRANSFERS TOWARDS THE COAST...THE CUTOFF LOW WILL RETROGRADE
HELPING TO BRING MOISTURE TOWARDS THE NORTHEAST AND OHIO VALLEY
MONDAY. THUS...CONTINUED TO CARRY SLIGHT CHANCE POPS STARTING
MONDAY MORNING IN THE RIDGES AND INCREASING AS THE DAY PROGRESSES
AND LOWER LEVELS MOISTEN. IN ADDITION...THE UPPER LEVEL TROUGH
OVER THE MIDWEST WILL MAKE ITS APPROACH LATER MONDAY AFTERNOON AND
WITH IT MODELS MAINTAIN ENOUGH INSTABILITY FOR THUNDERSTORM
DEVELOPMENT LATER MONDAY INTO TUESDAY AS THE COLD FRONT TAKES ITS
TIME CROSSING THE REGION.

MODEL AGREEMENT BEGINS TO DIVERGE LATER INTO TUESDAY AS THE ECMWF
IS SLOWER WITH THE FRONTAL PASSAGE AND IN ADDITION SUGGESTS THE
DEVELOPMENT OF ANOTHER 500HPA CUTOFF LOW CONTINUING PRECIPITATION
CHANCES THROUGHOUT THE DAY WEDNESDAY. THE GFS MAINTAINS AN OPEN
WAVE AND THUS HAS A FASTER SOLUTION ENDING PRECIPITATION SOONER ON
WEDNESDAY. DECIDED TO REMAIN CLOSER TO THE GFS BUT KEPT SLIGHT
CHANCE POPS THROUGH WEDNESDAY DUE TO THE UNCERTAINTY.


&&

.LONG TERM /THURSDAY THROUGH SATURDAY/...
12Z GFS/00Z ECMWF HAVE DIFFERENT DEPICTIONS IN THE EXTENDED...AND
THEREFORE CONFIDENCE IS BELOW AVERAGE. BOTH MODELS SHOW GENERAL
AGREEMENT THAT THERE WILL BE A NEARLY STATIONARY UPPER LEVEL
LOW/TROUGH NEAR THE CAROLINAS. HOWEVER...MULTIPLE RUNS OF THE GFS
KEEPS THIS FEATURE OVER THE ATLANTIC OCEAN WITH JUST SOME CLOUDS
LOCALLY...WHILE THE ECMWF HAS THE FEATURE INLAND ALONG THE EAST
COAST AND SPREADS RAIN AS FAR WEST AS WEST VIRGINIA AND EASTERN
OHIO. WITH NAEFS AND ECMWF ENSEMBLE KEEPING THE PATTERN A LITTLE
DRIER...HAVE ALSO STUCK WITH A DRIER FORECAST. IF THIS HOLDS...AND
THE GFS FORECAST VERIFIES...THIS PERIOD WILL BE QUITE WARM. GFS
BIAS-CORRECTED GRIDS AND NAEFS METEOGRAMS SUGGEST THAT 90 DEGREES IS
NOT OUT OF THE QUESTION FOR THE START OF THE MEMORIAL DAY WEEKEND.

&&

.AVIATION /09Z SUNDAY THROUGH THURSDAY/...
HIGH PRESSURE WILL KEEP SKIES MOSTLY CLEAR WITH ONLY A FEW CIRRUS.
WINDS BELOW 10 KTS FOR NEXT 24 HOURS.

.OUTLOOK...SUNDAY NIGHT THROUGH THURSDAY...
SUNDAY NIGHT SHOULD REMAIN DRY BEFORE COLD FRONT APPROACHES FROM THE
WEST ON MONDAY WHILE MOISTURE INCREASES FROM THE EAST AS LOW
PRESSURE MOVES UP THE EASTERN SEABOARD. RESTRICTIONS POSSIBLE
THROUGH WEDNESDAY. PRECIPITATION SHOULD THEN SHIFT EAST OF THE AREA
BY WEDNESDAY NIGHT WITH GENERAL VFR THURSDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$

000
FXUS61 KPHI 200834
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
434 AM EDT SUN MAY 20 2012

.SYNOPSIS...
AN AREA OF LOW PRESSURE OFF THE MID-ATLANTIC COAST WILL DRIFT
WESTWARD ON LAND LATER TODAY INTO TONIGHT. MEANWHILE, TROPICAL STORM
ALBERTO WILL MEANDER OFF THE SOUTH CAROLINA COAST THROUGH MONDAY,
BEFORE MOVING NORTHEAST AND WEAKENING THROUGH WEDNESDAY. A
FRONTAL BOUNDARY IS FORECAST TO AFFECT THE AREA TUESDAY NIGHT INTO
WEDNESDAY, BEFORE SLOWLY MOVING TO OUR SOUTH THROUGH THURSDAY. HIGH
PRESSURE MAY THEN BUILD ACROSS THE AREA FROM THE NORTHEAST FRIDAY
INTO SATURDAY, WITH THE POSSIBILITY OF A COLD FRONT LATE SATURDAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
TODAY...GUSTY NE WINDS OF 25 MPH DEVELOP BY MIDDAY AND TEMPS ARE
EXPECTED TO BE A COUPLE OF DEGREES COOLER THAN SATURDAY AS SOMEWHAT
COOLER MARINE AIR EVENTUALLY PENETRATES WESTWARD AFTER AN INITIALLY
VERY RAPID MORNING WARMUP. SHOWERS SHOULD SPREAD INLAND INTO SE DE
AND POSSIBLY THE SE NJ COAST BY DAYS END.

BLENDED NCEP STATISTICAL GUIDANCE FOR WINDS/TEMPS/DEWPOINTS THO
FAVORED THE WARMER NAM FOR TODAY WHICH ALSO AGREES BETTER WITH THE
WARMER ECMWF.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...
TONIGHT...A CONDUIT OF MOISTURE IN DEEP SE FLOW SHOULD NOT ONLY
DEVELOP SHOWERS ACROSS MOST OF THE AREA DURING THE NIGHT
/INSTABILITY BURST/ BUT 0.25 TO AS MUCH AS ISOLATED 1 INCH AMTS
ARE FCST BY 12Z MONDAY IN NJ/DE WITH LESSER AMTS IN PA/MD.

ISO THUNDER IS POSSIBLE IN COASTAL NJ/DE AFTER 05Z WITH INSTABILITY
ALOFT...VIA A SWI SUBZERO...SOME CAPE ON THE SE SIDE OF THE INVERTED
TROUGH /SE BL WIND/. THE PROB FOR THUNDER IS LOW ENOUGH NOT TO BE
IN THE LEGACY ZONES BUT DOES SHOW UP IN THE MORE DETAILED
POINT/CLICK INFORMATION.

BLENDED NCEP STATISTICAL GUIDANCE FOR WINDS/TEMPS.

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...
BROAD TROUGHING ALOFT WILL REMAIN ACROSS THE EAST COAST FOR MUCH OF
THE WEEK, WHICH WILL KEEP UNSETTLED WEATHER FOR MUCH OF THE EXTENDED
FORECAST. ON MONDAY, THE SURFACE LOW THAT MOVED INLAND TO OUR SOUTH
WILL WEAKEN, BUT AN ABUNDANCE OF MOISTURE WILL CONTINUE TO FLOW IN
ACROSS THE AREA. PWAT VALUES REACH 1.5-1.75 INCHES DURING THE DAY
MONDAY, SO THERE COULD BE A PERIOD OF MODERATE TO HEAVY RAIN ACROSS
THE AREA. THERE IS SOME INSTABILITY IN THE ATMOSPHERE, SO WE HAVE
ADDED A CHANCE OF THUNDERSTORMS.

A FRONTAL BOUNDARY IS EXPECTED TO APPROACH THE AREA TUESDAY, BEFORE
SETTLING ACROSS THE AREA TUESDAY NIGHT INTO WEDNESDAY. WITH THE
BROAD TROUGH ALOFT, SEVERAL VORT MAXES/SHORT WAVES WILL LIKELY CROSS
THE AREA DURING THIS TIME PERIOD. THEREFORE WE WILL KEEP A CHANCE OF
SHOWERS IN THE FORECAST, AND CONTINUE A CHANCE OF THUNDERSTORMS
SINCE THERE IS SOME INSTABILITY ACROSS THE AREA.

BY THURSDAY, THE FRONT SHOULD SINK TO OUR SOUTH, BUT FOR THURSDAY
THROUGH THE END OF THE WEEK, THE TROUGH ALOFT WILL BE SLOW TO PULL
OUT OF THE AREA. THIS WILL KEEP A SLIGHT CHANCE OF
SHOWERS/THUNDERSTORMS ACROSS THE AREA. THE SHOWER ACTIVITY WOULD
MOST LIKELY OCCUR DURING EACH AFTERNOON DUE TO THE DAYTIME HEATING.

THE NHC HAS NAMED TROPICAL STORM ALBERTO WHICH IS LOCATED OFF THE
SOUTH CAROLINA COAST. THE LATEST TRACK HAS THE STORM MEANDERING OFF
THE SOUTH CAROLINA COAST THROUGH MONDAY, THEN MOVING NORTHEAST AND
WEAKENING THROUGH WEDNESDAY. THE CURRENT TRACK KEEPS THE STORM AWAY
FROM OUR AREA, BUT WE WILL HAVE TO CONTINUE TO MONITOR THE FORECAST
IN CASE THE TRACK MOVES FURTHER WEST. VISIT THE NHC`S WEBSITE FOR
MORE INFORMATION ON THE TROPICAL STORM ALBERTO.

&&

.AVIATION /08Z SUNDAY THROUGH THURSDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.

THROUGH 12Z...VFR MOSTLY CLEAR WITH JUST SOME CIRRUS AROUND.
LIGHT NE WIND.

AFTER 12Z...VFR. MVFR CIGS MOVE WESTWARD ASHORE BETWEEN 16Z-19Z
FM VCNTY KACY TO KGED AND SPREAD NWWD THIS AFTN COVERING MOST OF
SE NJ AND MOST OF DE BY 00Z/21. NE WIND GUSTS 20-25 KTS BY NOON.
SCT SHOWERS DEVELOP VCNTY KACY THRU MOST OF S DE SOMETIME DURING
THE AFTN. FOR NOW THE FCST IN THE TAFS IS NEAR 00Z BUT SUBJECT TO
CHANGE BASED ON RADAR.

TONIGHT...MVFR CIGS SPREAD OVER ALL THE REGION DURING THE NIGHT AND
SHOWERS BECOME MORE WIDESPREAD. SHOWERS WILL BE BRIEFLY HEAVY IN
NJ/DE. ITS ALSO LIKELY THAT IFR CONDS DEVELOP IN SOME OF THE SHOWERS
AS WELL AS ST/FOG...MAINLY AFTER 05Z/21.


OUTLOOK...
MONDAY/MONDAY NIGHT...MVFR/IFR CIGS/VSBYS EXPECTED, ESPECIALLY WITH
SHOWERS. MOSTLY EAST/NORTHEAST WINDS AROUND 10-15 KNOTS.

TUESDAY/TUESDAY NIGHT...MVFR/IFR EARLY, POSSIBLY IMPROVING TO VFR BY
AFTERNOON EXCEPT IN SHOWERS/THUNDERSTORMS. EAST WINDS BECOMING
SOUTHEAST DURING THE DAY. MVFR/IFR CIGS/VSBYS POSSIBLE AT NIGHT.

WEDNESDAY/WEDNESDAY NIGHT...MOSTLY VFR, POSSIBLE MVFR IN
SHOWERS/THUNDERSTORMS DURING THE AFTERNOON. EAST/SOUTHEAST WINDS
5-10 KNOTS. MVFR/IFR CIGS/VSBYS POSSIBLE AT NIGHT.

THURSDAY...MVFR/IFR POSSIBLE EARLY, IMPROVING TO VFR BY AFTERNOON
EXCEPT IN SHOWERS/THUNDERSTORMS. SOUTHEAST WINDS AROUND 5-10 KNOTS.

&&

.MARINE...
TODAY AND TONIGHT...SCA CONTINUES AS POSTED. THE HAZARDOUS SEAS
HAVE BEEN IN PROGRESS OVER VIRTUALLY ALL THE ATLC WATERS FOR A DAY
NOW...THE EXCEPTION POSSIBLY IN PORTIONS OF ANZ450. ONSHORE WINDS
ARE MODELED TO INCREASE 5 TO 10 KTS TODAY THROUGHOUT THE WATERS
/HIGHER THAN YDY/ BEFORE WINDS SUBSIDE LATER TONIGHT. IF THE WIND
FCST IS CORRECT...SEAS TO 10 FEET WILL DEVELOP FOR THE DE COAST
TODAY. WE ADDED DE BAY TO SCA TODAY PER THE MODELED WIND INCREASE.

OUTLOOK...
THE SMALL CRAFT ADVISORY WILL REMAIN THROUGH MONDAY AS WAVEWATCH
GUIDANCE KEEPS SEAS ABOVE 5 FEET THROUGH THE TIME PERIOD. WE WILL
NEED TO CONTINUE TO MONITOR THE FORECAST TRACK FOR TROPICAL STORM
ALBERTO TO SEE IF ANY STRONG WINDS WILL MAKE IT ACROSS OUR WATERS.
THE LATEST TRACK FROM THE NHC KEEPS THE STORM FAR ENOUGH AWAY FROM
OUR WATERS TO NOT GET STORM FORCE WINDS. HOWEVER, SEAS MAY REMAIN
ELEVATED THROUGH WEDNESDAY, WHICH IS WHEN THE STORM IS EXPECTED TO
PASS TO OUR EAST.

&&

.FIRE WEATHER...
WE`LL CHECK WITH FORESTRY OFFICIALS AFTER 8AM TODAY TO SEE
WHETHER THEY PREFER AN SPS FOR THE 2P-5P PERIOD THIS AFTERNOON
FROM THE LEHIGH VALLEY INTO NW NJ WHEN RH IS BELOW 30 PCT...NE
WINDS WILL BE GUSTING TO 20 MPH...10 HR FUELS ARE IN THE 6 TO 9
PCT RANGE AFTER 4 SUCCESSIVE DRY DAYS.

&&

.TIDES/COASTAL FLOODING...
WITH A CONTINUED NORTHEAST TO EAST FLOW TONIGHT AND MONDAY, THERE
REMAINS THE POTENTIAL FOR SPOTTY MINOR TIDAL FLOODING...MAINLY THE
DELAWARE WATERS.

POSITIVE DEPARTURES AROUND A FOOT AND A QUARTER ARE NEEDED TO
REACH THE MINOR FLOODING THRESHOLD. WE WILL CONTINUE TO MONITOR
THE TRENDS ALONG WITH THE LATEST GUIDANCE.

00Z/20 MRPSSE GUIDANCE WILL BE AT LEAST HALF A FOOT TOO LOW FOR
TONIGHTS-SUNDAY NIGHT UPCOMING HIGH TIDE. SO FAR NO GUIDANCE
EXCEEDS THE THRESHOLD.

THINK WE WILL EVENTUALLY NEED A CF STATEMENT FOR TIDES NUDGING
MINOR FS OR JUST BLO BY 0.2 FT FOR THE TIDAL DELAWARE AS WELL AS
DE ATLC COAST THIS COMING SUNDAY NIGHT HIGH TIDE CYCLE.

BASICALLY THIS FOCUSES ON LEWES/REEDY/PHL.

NO ACTION ON THIS SHIFT DUE TO UNCERTAINTY AS WELL AS ONLY
"APPROACHING" THRESHOLD INSTEAD OF ANY CLEAR GUIDANCE EXCEEDING
THRESHOLD. PREDICTION FOR TONIGHT AT LEWES AT LEAST 5.7 AS PER OUR
LOCAL STATISTICAL PROGRAM.

&&

.RIP CURRENTS...
THE COMBINATION OF A 4 TO 6 FOOT EAST TO SOUTHEAST SWELL WITH AN 8
TO 10 SECOND PERIOD AND 1 TO 4 FEET OF WIND WAVES ON TOP OF THAT...
GENERATED BY AN INCREASING NORTHEAST WIND OF 20 TO OCCASIONALLY
25 KNOTS...PRODUCES AN ENVIRONMENT THAT RAISES THE RISK OF
RIP CURRENTS INTO THE HIGH LIKELIHOOD CATEGORY.

WE KNOW WATER TEMPERATURES ARE COLD FOR MOST RECREATIONAL BATHERS...
GENERALLY BETWEEN 55 AND 60 DEGREES...AND SO THERE ARE PROBABLY
FEW SWIMMERS. HOWEVER...IN THE INTEREST OF PROTECTION OF LIFE...
AND SINCE OUR SURF ZONE FORECAST HAS STARTED THIS SEASON...THE
HEADLINE INFORMATION HAS BEEN ISSUED.

DIMINISHING WIND AND SEAS ON MONDAY-TOMORROW SHOULD LOWER THE RISK TO
MODERATE.


&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...HIGH RIP CURRENT RISK THROUGH THIS EVENING FOR NJZ014-024>026.
DE...HIGH RIP CURRENT RISK THROUGH THIS EVENING FOR DEZ004.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT MONDAY FOR ANZ452>455.
     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 PM EDT MONDAY
     FOR ANZ450-451.
     SMALL CRAFT ADVISORY FROM 8 AM THIS MORNING TO 8 PM EDT THIS
     EVENING FOR ANZ430-431.

&&

$$
SYNOPSIS...ROBERTSON
NEAR TERM...DRAG 434
SHORT TERM...DRAG 434
LONG TERM...ROBERTSON
AVIATION...DRAG/ROBERTSON 434
MARINE...DRAG/ROBERTSON 434
FIRE WEATHER...434
TIDES/COASTAL FLOODING...434
RIP CURRENTS...434

000
FXUS61 KPHI 200738
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
338 AM EDT SUN MAY 20 2012

.SYNOPSIS...
AN AREA OF LOW PRESSURE OFF THE MID-ATLANTIC COAST WILL DRIFT
WESTWARD ON LAND LATER TODAY INTO TONIGHT. MEANWHILE, TROPICAL STORM
ALBERTO WILL MEANDER OFF THE SOUTH CAROLINA COAST THROUGH MONDAY,
BEFORE MOVING NORTHEAST AND WEAKENING THROUGH WEDNESDAY. A
FRONTAL BOUNDARY IS FORECAST TO AFFECT THE AREA TUESDAY NIGHT INTO
WEDNESDAY, BEFORE SLOWLY MOVING TO OUR SOUTH THROUGH THURSDAY. HIGH
PRESSURE MAY THEN BUILD ACROSS THE AREA FROM THE NORTHEAST FRIDAY
INTO SATURDAY, WITH THE POSSIBILITY OF A COLD FRONT LATE SATURDAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
RADIATIONAL COOLING IS IN PROGRESS AND NO SIGNIFICANT CHANGE TO
THE EARLIER FORECAST PHILOSOPHY/INFORMATION.

HOWEVER...CHANGES IN OUR WEATHER ARE BECOMING EVIDENT AND NOT TOO
FAR AWAY.

THE MOISTURE DISCONTINUITY /OUR DRY VERSUS WHAT IS COMING/ IS
EVIDENT ON OUR RADAR PRESENTATION JUST OFF THE LI AND NJ COASTS.
DEWPOINTS RISE CONSIDERABLY ACROSS THAT BOUNDARY... FROM NEAR 40
IN NJ TO THE LOWER 60S EAST OF BOUNDARY WHERE THERE IS ALSO A
MIDNIGHT SHIP REPORT OF MDT RAIN ABOUT 125 MI E OF KACY!

SATELLITE IMAGERY SHOWS CLOUDINESS AT VARIOUS LEVELS ADVANCING
INTO AND TOWARD OUR FORECAST AREA FROM THE SEPARATE LOW PRESSURE
SYSTEMS EMBEDDED WITHIN THE LARGE SCALE POSITIVE TILT SOUTHEAST
TROUGH ALOFT.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...
TODAY...GUSTY NE WINDS OF 25 MPH DEVELOP BY MIDDAY AND TEMPS ARE
EXPECTED TO BE A COUPLE OF DEGREES COOLER THAN SATURDAY AS FIRST
HIGH CLOUD INVADES WITH SHOWERS DEVELOPING IN S DE AND POSSIBLY
THE SE NJ COAST BY DAYS END. THE FCST POPS IN THE 330 AM PKG WILL
BE RAISED 10-20 PCT FM SE DEL TO KWWD NJ.

TONIGHT...A CONDUIT OF MOISTURE IN DEEP SE FLOW SHOULD NOT ONLY
DEVELOP SHOWERS ACROSS MOST OF THE AREA DURING THE NIGHT /INSTABILITY
BURST/ BUT 0.25 TO AS MUCH AS ISOLATED 1 INCH AMTS ARE FCST BY 12Z
MONDAY... IN NJ/DE WITH LESSER AMTS IN PA/MD. ISO THUNDER IS
POSSIBLE IN COASTAL NJ AFTER 05Z. WILL GRID ISO T IN COASTAL NJ/DE
FOR LATE TONIGHT. SWI DROP BLO 0 AND CAPE IS APPROACHING THE COAST
AS WELL AS KI NEAR 34. FCST POPS WILL RANGE FROM CHC IN NE PA TOP
LIKELY MOST OF THE REST OF THE REGION TO CATEGORICAL IN SSE DE AND
COASTAL S NJ.

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...
BROAD TROUGHING ALOFT WILL REMAIN ACROSS THE EAST COAST FOR MUCH OF
THE WEEK, WHICH WILL KEEP UNSETTLED WEATHER FOR MUCH OF THE EXTENDED
FORECAST. ON MONDAY, THE SURFACE LOW THAT MOVED INLAND TO OUR SOUTH
WILL WEAKEN, BUT AN ABUNDANCE OF MOISTURE WILL CONTINUE TO FLOW IN
ACROSS THE AREA. PWAT VALUES REACH 1.5-1.75 INCHES DURING THE DAY
MONDAY, SO THERE COULD BE A PERIOD OF MODERATE TO HEAVY RAIN ACROSS
THE AREA. THERE IS SOME INSTABILITY IN THE ATMOSPHERE, SO WE HAVE
ADDED A CHANCE OF THUNDERSTORMS.

A FRONTAL BOUNDARY IS EXPECTED TO APPROACH THE AREA TUESDAY, BEFORE
SETTLING ACROSS THE AREA TUESDAY NIGHT INTO WEDNESDAY. WITH THE
BROAD TROUGH ALOFT, SEVERAL VORT MAXES/SHORT WAVES WILL LIKELY CROSS
THE AREA DURING THIS TIME PERIOD. THEREFORE WE WILL KEEP A CHANCE OF
SHOWERS IN THE FORECAST, AND CONTINUE A CHANCE OF THUNDERSTORMS
SINCE THERE IS SOME INSTABILITY ACROSS THE AREA.

BY THURSDAY, THE FRONT SHOULD SINK TO OUR SOUTH, BUT FOR THURSDAY
THROUGH THE END OF THE WEEK, THE TROUGH ALOFT WILL BE SLOW TO PULL
OUT OF THE AREA. THIS WILL KEEP A SLIGHT CHANCE OF
SHOWERS/THUNDERSTORMS ACROSS THE AREA. THE SHOWER ACTIVITY WOULD
MOST LIKELY OCCUR DURING EACH AFTERNOON DUE TO THE DAYTIME HEATING.

THE NHC HAS NAMED TROPICAL STORM ALBERTO WHICH IS LOCATED OFF THE
SOUTH CAROLINA COAST. THE LATEST TRACK HAS THE STORM MEANDERING OFF
THE SOUTH CAROLINA COAST THROUGH MONDAY, THEN MOVING NORTHEAST AND
WEAKENING THROUGH WEDNESDAY. THE CURRENT TRACK KEEPS THE STORM AWAY
FROM OUR AREA, BUT WE WILL HAVE TO CONTINUE TO MONITOR THE FORECAST
IN CASE THE TRACK MOVES FURTHER WEST. VISIT THE NHC`S WEBSITE FOR
MORE INFORMATION ON THE TROPICAL STORM ALBERTO.

&&

.AVIATION /08Z SUNDAY THROUGH THURSDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.

THROUGH 12Z...VFR MOSTLY CLEAR WITH JUST SOME CIRRUS AROUND.
LIGHT NE WIND.

AFTER 12Z...VFR. MVFR CIGS DEVELOP BETWEEN 16Z-19Z FM VCNTY KACY
TO KGED AND SPREAD NWWD THIS AFTN COVERING MOST OF SE NJ AND MOST
OF DE BY 00Z/21. NE WIND GUSTS 20-25 KTS BY NOON. SCT SHOWERS
DEVELOP VCNTY KACY THRU MOST OF S DE SOMETIME DURING THE AFTN. FOR
NOW THE FCST IN THE TAFS IS NEAR 00Z BUT SUBJECT TO CHANGE BASED
ON RADAR.

TONIGHT...MVFR CIGS SPREAD OVER ALL THE REGION DURING THE NIGHT AND
SHOWERS BECOME MORE WIDESPREAD. SHOWERS WILL BE BRIEFLY HEAVY IN
NJ. ITS ALSO LIKELY THAT IFR CONDS DEVELOP IN SOME OF THE SHOWERS
AS WELL AS ST/FOG...MAINLY AFTER 05Z/21.


OUTLOOK...
MONDAY/MONDAY NIGHT...MVFR/IFR CIGS/VSBYS EXPECTED, ESPECIALLY WITH
SHOWERS. MOSTLY EAST/NORTHEAST WINDS AROUND 10-15 KNOTS.

TUESDAY/TUESDAY NIGHT...MVFR/IFR EARLY, POSSIBLY IMPROVING TO VFR BY
AFTERNOON EXCEPT IN SHOWERS/THUNDERSTORMS. EAST WINDS BECOMING
SOUTHEAST DURING THE DAY. MVFR/IFR CIGS/VSBYS POSSIBLE AT NIGHT.

WEDNESDAY/WEDNESDAY NIGHT...MOSTLY VFR, POSSIBLE MVFR IN
SHOWERS/THUNDERSTORMS DURING THE AFTERNOON. EAST/SOUTHEAST WINDS
5-10 KNOTS. MVFR/IFR CIGS/VSBYS POSSIBLE AT NIGHT.

THURSDAY...MVFR/IFR POSSIBLE EARLY, IMPROVING TO VFR BY AFTERNOON
EXCEPT IN SHOWERS/THUNDERSTORMS. SOUTHEAST WINDS AROUND 5-10 KNOTS.

&&

.MARINE...
TODAY AND TONIGHT...SCA CONTINUES AS POSTED.

OUTLOOK...
THE SMALL CRAFT ADVISORY WILL REMAIN THROUGH MONDAY AS WAVEWATCH
GUIDANCE KEEPS SEAS ABOVE 5 FEET THROUGH THE TIME PERIOD. WE WILL
NEED TO CONTINUE TO MONITOR THE FORECAST TRACK FOR TROPICAL STORM
ALBERTO TO SEE IF ANY STRONG WINDS WILL MAKE IT ACROSS OUR WATERS.
THE LATEST TRACK FROM THE NHC KEEPS THE STORM FAR ENOUGH AWAY FROM
OUR WATERS TO NOT GET STORM FORCE WINDS. HOWEVER, SEAS MAY REMAIN
ELEVATED THROUGH WEDNESDAY, WHICH IS WHEN THE STORM IS EXPECTED TO
PASS TO OUR EAST.

&&

.TIDES/COASTAL FLOODING...
WITH A CONTINUED NORTHEAST TO EAST FLOW ON SUNDAY NIGHT AND MONDAY,
THERE REMAINS THE POTENTIAL FOR SPOTTY MINOR TIDAL FLOODING DURING
THAT PERIOD. POSITIVE DEPARTURES AROUND A FOOT AND A QUARTER ARE
NEEDED TO REACH THE MINOR FLOODING THRESHOLD. WE WILL CONTINUE TO
MONITOR THE TRENDS ALONG WITH THE LATEST GUIDANCE.

00Z/20 MRPSSE GUIDANCE JUST RCD WILL BE AT LEAST HALF A FOOT TOO
LOW FOR TONIGHTS-SUNDAY NIGHT UPCOMING HIGH TIDE. SO FAR NO
GUIDANCE EXCEEDS THE THRESHOLD.

AS OF 145 AM... I THINK WE WILL EVENTUALLY NEED A CF STATEMENT FOR
TIDES NUDGING MINOR FS OR JUST BLO BY 0.2 FT FOR THE TIDAL
DELAWARE AS WELL AS DE ATLC COAST. BASICALLY THIS IS FOCUSES ON
LEWES/REEDY/PHL. NOT TAKING ACTION ON THIS SHIFT DUE TO
UNCERTAINTY AS WELL AS APPROACHING THRESHOLD INSTEAD OF ANY CLEAR
GUIDANCE EXCEEDING THRESHOLD. PREDICTION FOR TONIGHT AT LEWES AT
LEAST 5.7.

&&

.RIP CURRENTS...
AN ONSHORE FLOW CONTINUES, RESULTING IN ELEVATED SEAS. IN ADDITION,
A SWELL COMPONENT IS PRESENT WITH LOW PRESSURE SLIDING WEST-SOUTHWEST
AND TOWARD THE LOWER MID ATLANTIC REGION.

AN RP.S WILL BE ISSUED AROUND 4AM FOR A HIGH RISK OF RIP CURRENTS
TODAY ALONG THE NJ AND DE COASTS.

THE DATA USED FOR 44009 8 FT 8 SEC 04022 NEW MOON. VALUES EASILY
IN HIGH RISK CATEGORY. WONT BE SURPRISED TO SEE THE SEAS GROW TO
10 FT AT 44009. 44009 FREQUENCY DATA IS SHOWING A 10 SEC PERIOD
SWELL ALSO...IN ADDITION TO THE PRIMARY 8 SEC PERIOD.

FORTUNATELY WATER TEMPS AS OBSERVED THRU BUOY AND SAT IMAGERY THE
LAST 12 HRS OFFERS 55-60F A BIT ON THE COLD SIDE FOR TYPICAL
RECREATIONAL SWIMMING.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...HIGH RIP CURRENT RISK THROUGH THIS EVENING FOR NJZ014-024>026.
DE...HIGH RIP CURRENT RISK THROUGH THIS EVENING FOR DEZ004.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT MONDAY FOR ANZ452>455.
     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 PM EDT MONDAY
     FOR ANZ450-451.
     SMALL CRAFT ADVISORY FROM 8 AM THIS MORNING TO 8 PM EDT THIS
     EVENING FOR ANZ430-431.

&&

$$
SYNOPSIS...ROBERTSON
NEAR TERM...DRAG
SHORT TERM...DRAG
LONG TERM...ROBERTSON
AVIATION...DRAG/ROBERTSON
MARINE...DRAG/ROBERTSON
TIDES/COASTAL FLOODING...DRAG
RIP CURRENTS...DRAG

000
FXUS61 KCTP 200615
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
215 AM EDT SUN MAY 20 2012

.SYNOPSIS...
THE STRONG 500 HPA RIDGE AND WEAK SURFACE RIDGE SHOULD PROVIDE FOR
ANOTHER FINE DAY SUNDAY. A NORTHERN STREAM WAVE APPROACHING COULD
PULL THE FIRST NAMED STORM OF THE YEAR...ALBERTO...UP THE COAST
MONDAY-TUESDAY WHICH COULD BRING A CHANCE OF RAIN TO EASTERN PA
MONDAY EVENING AND TUESDAY. A WEAK TROUGH WILL DOMINATE THROUGH
LATE WEDNESDAY...THEN A 500 HPA RIDGE SHOULD BUILD OVER THE
EASTERN UNITED STATES. BY THE END OF THE WEEK A 5880M RIDGE WITH
+1 TO +2 STANDARD DEVIATIONS HEIGHTS WILL BE OVER THE OHIO
VALLEY. IT SHOULD RAPIDLY WARM UP HERE THURSDAY INTO SATURDAY.
SHOULD BE WELL ABOVE NORMAL HERE TEMPERATURE WISE THUR-SUNDAY.

&&

.NEAR TERM /UNTIL 8 AM THIS MORNING/...
HIGH PRESSURE OVER THE REGION WILL PROVIDE ANOTHER MCLEAR NIGHT
ACROSS CENTRAL PA WITH LIGHT WINDS. ORIGINALLY COOL/DRY AIR MASS
HAS MODIFIED CONSIDERABLY OVER THE LAST COUPLE DAYS. 06Z
TEMPS/DWPTS SEVERAL DEG ABV THOSE OF 24HRS AGO...SUGGESTING LOWS
THIS AM RANGING FROM THE U40S N MTNS...TO THE M50S ACROSS THE
LOWER SUSQ VALLEY.

CAN/T RULE OUT A BIT OF FOG ARND DAWN OVR THE SUSQ VALLEY...WHERE
NAM AND HRRR SFC RH RISES TO NR 100PCT BY 09Z. HOWEVER...HAVE
REMOVED MENTION IN FCST...GIVEN UNCERTAINTY AND ISOLATED NATURE IF
IT DOES FORM.

&&

.SHORT TERM /8 AM THIS MORNING THROUGH 6 PM MONDAY/...
FAIR WX CONTINUES SUNDAY AS A RIDGE OVER THE ATLANTIC EXTENDS INTO
OUR REGION. WE SHOULD HAVE WEAK EASTERLY FLOW SLIGHT RISE IN
RELATIVE HUMIDITY.

SHOULD BE A GOOD DAY AND NEW GUIDANCE STILL SEEMS TO KEEP HINTS OF
RAIN OFF UNTIL MONDAY. STILL NOT AN ENSEMBLE MEMBER HAS ANY RAIN
OVER OUR AREA UNTIL AFTER ABOUT ABOUT 1200 UTC ON MONDAY.

&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
UPDATED GRIDS/FORECAST TO SHOW THE LATEST GEFS/SREF WITH BEST
CHANCE RAIN IN EXTREME SOUTHEAST PA A FEW HOURS EITHER SIDE OF 8
AM MONDAY. 18Z GEFS WOULD FAVOR SOME LIGHT RAIN IN EASTERN PA
BETWEEN 8 AND 4 PM ON MONDAY. SOME LOCALLY ENHANCED POPS IN NW PA
TOO MONDAY WITH THE MODEST PW SURGE AHEAD OF THE NORTHERN STREAM
FRONTAL SYSTEM. WOULD BE SHRA WITH TSTMS IN NW PA WITH CAPE VALUES
IN THE 600 TO 800JK-1 RANGE. IN EASTERN PA THE RAIN WOULD BE ON
COOLER MORE STABLE EASTERLY FLOW.

THE FRONT AND MOISTURE GET HUNG UP OVER PA TUESDAY. THUS THE
MODELS PRODUCE OVER 800JKG-1 OF CAPE TUESDAY. NO WINDS TO SPEAK
OF. BUT MODEST PROBABILITIES SHOWERS AND THUNDER LATE MORNING INTO
THE EVENING ON TUESDAY.

STILL SOME INSTABILITY TO DEAL WITH IN EASTERN PA WED. A FEW MORE
SHOWERS/TSTMS WITH MODEST CAPE MAINLY BELOW ABOUT 800JKG-1.

WE COOL OFF MONDAY-TUES WITH CLOUDS AND RAIN...EASTERLY FLOW
MONDAY IN EASTERN PA WITH COASTAL SYSTEM (ALBERTO). ALBERTO TO SE
AND AND SHORT WAVE AND FRONT TO NW MAKE MON-TUES BEST RAINFALL
POTENTIAL DAYS. AT THIS TIME LOOKING AT A FEW TENTHS. NOTHING BIG
AS PROBABILITIES OF 0.50 AND 1.00 INCHES STAY TO OUR EAST.

TRIED TO KEEP AS MUCH OF THE LATER PART OF THE WEEK DRY...GIVEN
BUILDING RIDGE ALOFT.

KEY THING IS WITH CLOSE 5880M RIDGE BUILDING IN LATER IN
WEEK...SURGE OF ABOVE NORMAL 850 HPA TEMPS WITH RELATIVELY LOW PW
VALUES SUGGESTING WARMING UP THURSDAY AND WARMER STILL FRIDAY AND
SATURDAY.

&&

.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
A RIDGE OF HIGH PRESSURE WILL REMAIN NEARLY STATIONARY OVER
PENNSYLVANIA THROUGH SUNDAY...CONTINUING A PERIOD OF VFR
CONDITIONS WITH CLEAR SKIES AND LIGHT WINDS.

EASTERLY FLOW BEGINS TO INCREASE ACROSS THE REGION ON SUNDAY.
CLOUDS INCREASE SUNDAY NIGHT INTO MONDAY AS A DEEP LOW BACKS INTO
THE REGION FROM THE SOUTHEAST. SHOWERY WEATHER RETURNS EARLY
MONDAY WITH MVFR TO IFR CONDITIONS IN LOW CIGS AND VSBY POSSIBLE
IN RAIN SHOWERS ALONG THE LOWER SUSQ TAF SITES /MDT-LNS AND POSS
IPT/.

OUTLOOK...
SUN...VFR WITH A LIGHT...MAINLY EASTERLY WIND.
MON...SCATTERED MVFR CIGS AND VSBYS IN SHOWERS AND ISOLD
THUNDERSTORMS.
MON NIGHT THROUGH WEDNESDAY...MORE WIDESPREAD
REDUCED CIGS AND VSBYS LIKELY IN SHOWERS AND SCTD TSRA.
THU...PRIMARILY VFR. SCT SHRA/TSTM POSS MAINLY SE.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...GRUMM
NEAR TERM...FITZGERALD
SHORT TERM...GRUMM
LONG TERM...GRUMM/MARTIN
AVIATION...RXR

000
FXUS61 KPHI 200605
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
205 AM EDT SUN MAY 20 2012

.SYNOPSIS...
HIGH PRESSURE CENTERED ACROSS THE NORTHEAST USA WILL SHIFT TO NEAR
NOVA SCOTIA THIS AFTERNOON. MEANWHILE, LOW PRESSURE ABOUT 200 MILES
EAST OF NORFOLK VIRGINIA WILL MOVE WEST TOWARD THE VIRGINIA CAPES
WHILE TROPICAL STORM ALBERTO MEANDERS OFF THE SOUTHEAST COAST OF
THE UNITED STATES INTO MONDAY NIGHT. A SLOW MOVING FRONTAL BOUNDARY
IS FORECAST TO SETTLE INTO OUR AREA LATER TUESDAY AND POSSIBLY
LINGER INTO THURSDAY. HIGH PRESSURE IS ANTICIPATED TO BUILD INTO
OUR REGION FROM THE NORTHEAST FOR FRIDAY AND SATURDAY.

&&

.NEAR TERM /UNTIL 8 AM THIS MORNING/...
1230 AM EST...PRIMARY ADJUSTMENT WAS TO LOWER THE DEWPOINTS SEVERAL
DEGS THRU THE NIGHT.

OTHERWISE ANOTHER BEAUTIFUL NIGHT ACROSS OUR AREA.

RADIATIONAL COOLING IS IN PROGRESS AND NO SIGNIFICANT CHANGE TO
THE EARLIER FORECAST PHILOSOPHY/INFORMATION.

HOWEVER...CHANGES IN OUR WEATHER ARE BECOMING EVIDENT AND NOT TOO
FAR AWAY.

THE MOISTURE DISCONTINUITY /OUR DRY VERSUS WHAT IS COMING/ IS
EVIDENT ON OUR RADAR PRESENTATION JUST OFF THE LI AND NJ COASTS.
DEWPOINTS RISE CONSIDERABLY ACROSS THAT BOUNDARY... FROM NEAR 40
IN NJ TO THE LOWER 60S EAST OF BOUNDARY WHERE THERE IS ALSO A
MIDNIGHT SHIP REPORT OF MDT RAIN ABOUT 125 MI E OF KACY!

SATELLITE IMAGERY SHOWS CLOUDINESS AT VARIOUS LEVELS ADVANCING
INTO AND TOWARD OUR FORECAST AREA FROM THE SEPARATE LOW PRESSURE
SYSTEMS EMBEDDED WITHIN THE LARGE SCALE POSITIVE TILT SOUTHEAST
TROUGH ALOFT.

&&

.SHORT TERM /8 AM THIS MORNING THROUGH 6 AM MONDAY/...
TODAY...GUSTY NE WINDS OF 25 MPH DEVELOP BY MIDDAY AND TEMPS ARE
EXPECTED TO BE A COUPLE OF DEGREES COOLER THAN SATURDAY AS FIRST
HIGH CLOUD INVADES WITH SHOWERS DEVELOPING IN S DE AND POSSIBLY
THE SE NJ COAST BY DAYS END. THE FCST POPS IN THE 330 AM PKG WILL
BE RAISED 10-20 PCT FM SE DEL TO KWWD NJ.

TONIGHT...A CONDUIT OF MOISTURE IN DEEP SE FLOW SHOULD NOT ONLY
DEVELOP SHOWERS ACROSS MOST OF THE AREA DURING THE NIGHT /INSTABILITY
BURST/ BUT 0.25 TO AS MUCH AS ISOLATED 1 INCH AMTS ARE FCST BY 12Z
MONDAY... IN NJ/DE WITH LESSER AMTS IN PA/MD. ISO THUNDER IS
POSSIBLE IN COASTAL NJ AFTER 05Z. WILL GRID ISO T IN COASTAL NJ/DE
FOR LATE TONIGHT. SWI DROP BLO 0 AND CAPE IS APPROACHING THE COAST
AS WELL AS KI NEAR 34. FCST POPS WILL RANGE FROM CHC IN NE PA TOP
LIKELY MOST OF THE REST OF THE REGION TO CATEGORICAL IN SSE DE AND
COASTAL S NJ.

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...
AS WEAK LOW PRESSURE MOVES ONSHORE AROUND SOUTHEASTERN VIRGINIA
AND NORTHEASTERN NORTH CAROLINA LATE ON SUNDAY, CLOUDS AND
EVENTUALLY SOME SHOWERS WILL BEGIN TO SPREAD INTO OUR REGION FROM
THE SOUTHEAST ON SUNDAY NIGHT. IT APPEARS AS THOUGH THE BEST
CHANCE FOR SHOWERS IN OUR FORECAST AREA WILL BE ON MONDAY AS THE
BULK OF THE MOISTURE ASSOCIATED WITH THE DECAYING LOW WORKS ITS
WAY TO THE NORTHWEST AND NORTH.

WHILE A FAIR AMOUNT OF LOW LEVEL MOISTURE SHOULD LINGER IN OUR
REGION FOR MONDAY NIGHT INTO TUESDAY MORNING, THE SHOWER ACTIVITY
IS EXPECTED TO DIMINISH A BIT WITH THE ABSENCE OF A SIGNIFICANT
FOCUSING MECHANISM.

A SLOW MOVING BOUNDARY FROM THE WEST SHOULD BEGIN TO APPROACH
FROM THE WEST ON TUESDAY BEFORE MOVING INTO OUR REGION FOR TUESDAY
NIGHT AND WEDNESDAY. THE SOUTHERLY FLOW AHEAD OF THE BOUNDARY
SHOULD BRING INCREASING LOW LEVEL MOISTURE AND INCREASING
INSTABILITY. AS THE BOUNDARY NEARS, WE ARE ANTICIPATING SCATTERED
SHOWERS AND THUNDERSTORMS FOR TUESDAY AFTERNOON AND TUESDAY
EVENING. THE CHANCE FOR SHOWERS AND THUNDERSTORMS WILL CONTINUE
INTO WEDNESDAY. WITH A RELATIVELY WEAK FLOW IN THE LOW AND MID
LEVELS OF THE ATMOSPHERE, ANY SHOWERS AND THUNDERSTORMS WILL BE
SLOW MOVING AND THEY COULD LEAVE MODERATE TO HEAVY RAINFALL AT
SOME LOCATIONS.

THE FRONTAL BOUNDARY IS EXPECTED TO WEAKEN ON THURSDAY WITH HIGH
PRESSURE EXPECTED TO PUSH DOWN INTO OUR REGION FROM THE NORTH AND
NORTHEAST FOR FRIDAY AND SATURDAY. WHILE SHOWERS MAY LINGER INTO
THURSDAY, A TREND TOWARD DRY WEATHER IS EXPECTED FOR FRIDAY AND
SATURDAY.

TEMPERATURES SHOULD BE NEAR NORMAL FOR THIS TIME OF THE YEAR FROM
SUNDAY NIGHT THROUGH THURSDAY NIGHT. WITH DRY AIR BUILDING INTO
OUR REGION, ABOVE NORMAL TEMPERATURES ARE EXPECTED FOR FRIDAY INTO
SATURDAY. TEMPERATURES MAY RISE WELL INTO THE 80S ON SATURDAY.

&&

.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.

THROUGH 12Z...VFR MOSTLY CLEAR WITH JUST SOME CIRRUS AROUND.
LIGHT NE WIND.

AFTER 12Z...VFR. MVFR CIGS DEVELOP BETWEEN 16Z-19Z FM VCNTY KACY
TO KGED AND SPREAD NWWD THIS AFTN COVERING MOST OF SE NJ AND MOST
OF DE BY 00Z/21. NE WIND GUSTS 20-25 KTS BY NOON. SCT SHOWERS
DEVELOP VCNTY KACY THRU MOST OF S DE SOMETIME DURING THE AFTN. FOR
NOW THE FCST IN THE TAFS IS NEAR 00Z BUT SUBJECT TO CHANGE BASED
ON RADAR.

TONIGHT...MVFR CIGS SPREAD OVER ALL THE REGION DURING THE NIGHT AND
SHOWERS BECOME MORE WIDESPREAD. SHOWERS WILL BE BRIEFLY HEAVY IN
NJ. ITS ALSO LIKELY THAT IFR CONDS DEVELOP IN SOME OF THE SHOWERS
AS WELL AS ST/FOG...MAINLY AFTER 05Z/21.


OUTLOOK...
MONDAY...DETERIORATING CONDITIONS AS SHOWERS CONTINUE TO MOVE INTO
OUR REGION FROM THE SOUTH AND EAST. NORTHEAST WIND 10 KNOTS OR
LESS.

MONDAY NIGHT THROUGH WEDNESDAY NIGHT...MVFR/IFR CEILING AND
VISIBILITY VALUES ARE POSSIBLE, ALONG WITH SCATTERED SHOWERS,
DURING THE OVERNIGHT AND MORNING HOURS. MAINLY VFR DURING THE
AFTERNOON AND EVENING HOURS EXCEPT IN SCATTERED SHOWERS AND
THUNDERSTORMS. VARIABLE WIND 10 KNOTS OR LESS.

THURSDAY...MVFR/IFR CEILING AND VISIBILITY VALUES ARE POSSIBLE IN
THE MORNING. VFR WITH A SLIGHT CHANCE OF SHOWERS IN THE AFTERNOON.
SOUTHEAST WIND 10 KNOTS OR LESS.

&&

.MARINE...
RAN THE TROPICAL FORMATTER ON PWS AND NO MENTION OF TROPICAL IN
THE 11PM CWF.

SCA CONTINUES AS POSTED. IN ALL LIKELIHOOD AN EXTENSION IN TIME
IS PROBABLE WITH THE 330 AM FCST ...WELL INTO MONDAY.

ANTICIPATING AT 330AM ADDING DE BAY TO THE SCA FOR THE DAYLIGHT HOURS
SUNDAY AND POSSIBLY SUNDAY NIGHT AS WELL...

AN ONSHORE FLOW WILL CONTINUE THROUGH SUNDAY AS LOW PRESSURE OFF
THE VIRGINIA COAST SLIDES WEST-SOUTHWESTWARD. THIS WILL MAINTAIN
HIGHER WINDS AND SEAS OVER THE SOUTHERN PART OF OUR COASTAL
WATERS. THERE MAY BE AN UPTICK IN THE WINDS OVER DELAWARE BAY
SUNDAY, ESPECIALLY THE LOWER PORTION, BUT FOR NOW WE HELD OFF ON
A SMALL CRAFT ADVISORY. A SMALL CRAFT ADVISORY CONTINUES THOUGH
SOUTH OF LITTLE EGG INLET, AND A SMALL CRAFT ADVISORY FOR
HAZARDOUS SEAS IS IN EFFECT FARTHER NORTH.

OUTLOOK...
WIND SPEEDS ARE FORECAST TO REMAIN BELOW THE SMALL CRAFT ADVISORY
CRITERION FOR THE PERIOD FROM SUNDAY NIGHT THROUGH THURSDAY.

WAVE HEIGHTS ON OUR OCEAN WATERS SHOULD REMAIN AT OR JUST ABOVE 5
FEET ON SUNDAY NIGHT INTO MONDAY. FOR NOW, WE WILL KEEP THE SMALL
CRAFT ADVISORY GOING UNTIL 600 AM MONDAY.

AS LOW PRESSURE PASSES WELL TO OUR EAST, WAVES ON OUR OCEAN
WATERS COULD REMAIN AT OR ABOVE 5 FEET FOR MONDAY NIGHT, TUESDAY
AND TUESDAY NIGHT, MAINLY IN SWELLS. WAVE HEIGHTS ARE ANTICIPATED
TO SUBSIDE FOR WEDNESDAY AND THURSDAY.

&&

.TIDES/COASTAL FLOODING...
WITH A CONTINUED NORTHEAST TO EAST FLOW ON SUNDAY NIGHT AND MONDAY,
THERE REMAINS THE POTENTIAL FOR SPOTTY MINOR TIDAL FLOODING DURING
THAT PERIOD. POSITIVE DEPARTURES AROUND A FOOT AND A QUARTER ARE
NEEDED TO REACH THE MINOR FLOODING THRESHOLD. WE WILL CONTINUE TO
MONITOR THE TRENDS ALONG WITH THE LATEST GUIDANCE.

00Z/20 MRPSSE GUIDANCE JUST RCD WILL BE AT LEAST HALF A FOOT TOO
LOW FOR TONIGHTS-SUNDAY NIGHT UPCOMING HIGH TIDE. SO FAR NO
GUIDANCE EXCEEDS THE THRESHOLD.

AS OF 145 AM... I THINK WE WILL EVENTUALLY NEED A CF STATEMENT FOR
TIDES NUDGING MINOR FS OR JUST BLO BY 0.2 FT FOR THE TIDAL
DELAWARE AS WELL AS DE ATLC COAST. BASICALLY THIS IS FOCUSES ON
LEWES/REEDY/PHL. NOT TAKING ACTION ON THIS SHIFT DUE TO
UNCERTAINTY AS WELL AS APPROACHING THRESHOLD INSTEAD OF ANY CLEAR
GUIDANCE EXCEEDING THRESHOLD. PREDICTION FOR TONIGHT AT LEWES AT
LEAST 5.7.

&&

.RIP CURRENTS...
AN ONSHORE FLOW CONTINUES, RESULTING IN ELEVATED SEAS. IN ADDITION,
A SWELL COMPONENT IS PRESENT WITH LOW PRESSURE SLIDING WEST-SOUTHWEST
AND TOWARD THE LOWER MID ATLANTIC REGION.

AN RP.S WILL BE ISSUED AROUND 4AM FOR A HIGH RISK OF RIP CURRENTS
TODAY ALONG THE NJ AND DE COASTS.

THE DATA USED FOR 44009 8 FT 8 SEC 04022 NEW MOON. VALUES EASILY
IN HIGH RISK CATEGORY. WONT BE SURPRISED TO SEE THE SEAS GROW TO
10 FT AT 44009. 44009 FREQUENCY DATA IS SHOWING A 10 SEC PERIOD
SWELL ALSO...IN ADDITION TO THE PRIMARY 8 SEC PERIOD.

FORTUNATELY WATER TEMPS AS OBSERVED THRU BUOY AND SAT IMAGERY THE
LAST 12 HRS OFFERS 55-60F A BIT ON THE COLD SIDE FOR TYPICAL
RECREATIONAL SWIMMING.


&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT MONDAY FOR ANZ452>455.
     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 AM EDT MONDAY
     FOR ANZ450-451.

&&

$$
SYNOPSIS...DRAG/GORSE/IOVINO
NEAR TERM...DRAG 204A
SHORT TERM...DRAG 204A
LONG TERM...IOVINO
AVIATION...DRAG/IOVINO
MARINE...DRAG/IOVINO 204A
TIDES/COASTAL FLOODING...204A
RIP CURRENTS...204A

000
FXUS61 KCTP 200556
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
156 AM EDT SUN MAY 20 2012

.SYNOPSIS...
THE STRONG 500 HPA RIDGE AND WEAK SURFACE RIDGE SHOULD PROVIDE FOR
ANOTHER FINE DAY SUNDAY. A NORTHERN STREAM WAVE APPROACHING COULD
PULL THE FIRST NAMED STORM OF THE YEAR...ALBERTO...UP THE COAST
MONDAY-TUESDAY WHICH COULD BRING A CHANCE OF RAIN TO EASTERN PA
MONDAY EVENING AND TUESDAY. A WEAK TROUGH WILL DOMINATE THROUGH
LATE WEDNESDAY...THEN A 500 HPA RIDGE SHOULD BUILD OVER THE
EASTERN UNITED STATES. BY THE END OF THE WEEK A 5880M RIDGE WITH
+1 TO +2 STANDARD DEVIATIONS HEIGHTS WILL BE OVER THE OHIO
VALLEY. IT SHOULD RAPIDLY WARM UP HERE THURSDAY INTO SATURDAY.
SHOULD BE WELL ABOVE NORMAL HERE TEMPERATURE WISE THUR-SUNDAY.

&&

.NEAR TERM /UNTIL 8 AM THIS MORNING/...
MOSTLY CLEAR SKIES OVER NIGHT. VERY THIN CIRRUS AND SOME MOISTURE
IN WV OVER WESTERN PA. QUITE DRY TO OUR EAST IN WV CHANNEL NEAR THE
AREA OF HIGH PRESSURE OVER SOUTHERN NEW ENGLAND AND LONG ISLAND.

TEMPERATURES FALLING NICELY MOSTLY LOWER 60S IN NORTH TO MID 60S
IN SOME WARMER URBAN AREAS IN SOUTH.

WEAK HIGH PRESSURE WILL KEEP ITS GRIP OVER NIGHT. A FANTASTIC
OVERNIGHT TEMPS SHOULD BOTTOM OUT IN THE 40S AND 50S. OPEN THE
WINDOWS FOR SOME NATURAL AC...KEEP AN EXTRA QUILT NEARBY COULD GET
CHILLY BEFORE SUNRISE.

EXPECT SOME PATCHY FOG IN NORTHERN VALLEYS ESPECIALLY RIVER
VALLEYS, STREAMS, AND PONDS.

GRID/FORECAST EDITS WERE MINOR.

&&

.SHORT TERM /8 AM THIS MORNING THROUGH 6 PM MONDAY/...
FAIR WX CONTINUES SUNDAY AS A RIDGE OVER THE ATLANTIC EXTENDS INTO
OUR REGION. WE SHOULD HAVE WEAK EASTERLY FLOW SLIGHT RISE IN
RELATIVE HUMIDITY.

SHOULD BE A GOOD DAY AND NEW GUIDANCE STILL SEEMS TO KEEP HINTS OF
RAIN OFF UNTIL MONDAY. STILL NOT AN ENSEMBLE MEMBER HAS ANY RAIN
OVER OUR AREA UNTIL AFTER ABOUT ABOUT 1200 UTC ON MONDAY.

&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
UPDATED GRIDS/FORECAST TO SHOW THE LATEST GEFS/SREF WITH BEST
CHANCE RAIN IN EXTREME SOUTHEAST PA A FEW HOURS EITHER SIDE OF 8
AM MONDAY. 18Z GEFS WOULD FAVOR SOME LIGHT RAIN IN EASTERN PA
BETWEEN 8 AND 4 PM ON MONDAY. SOME LOCALLY ENHANCED POPS IN NW PA
TOO MONDAY WITH THE MODEST PW SURGE AHEAD OF THE NORTHERN STREAM
FRONTAL SYSTEM. WOULD BE SHRA WITH TSTMS IN NW PA WITH CAPE VALUES
IN THE 600 TO 800JK-1 RANGE. IN EASTERN PA THE RAIN WOULD BE ON
COOLER MORE STABLE EASTERLY FLOW.

THE FRONT AND MOISTURE GET HUNG UP OVER PA TUESDAY. THUS THE
MODELS PRODUCE OVER 800JKG-1 OF CAPE TUESDAY. NO WINDS TO SPEAK
OF. BUT MODEST PROBABILITIES SHOWERS AND THUNDER LATE MORNING INTO
THE EVENING ON TUESDAY.

STILL SOME INSTABILITY TO DEAL WITH IN EASTERN PA WED. A FEW MORE
SHOWERS/TSTMS WITH MODEST CAPE MAINLY BELOW ABOUT 800JKG-1.

WE COOL OFF MONDAY-TUES WITH CLOUDS AND RAIN...EASTERLY FLOW
MONDAY IN EASTERN PA WITH COASTAL SYSTEM (ALBERTO). ALBERTO TO SE
AND AND SHORT WAVE AND FRONT TO NW MAKE MON-TUES BEST RAINFALL
POTENTIAL DAYS. AT THIS TIME LOOKING AT A FEW TENTHS. NOTHING BIG
AS PROBABILITIES OF 0.50 AND 1.00 INCHES STAY TO OUR EAST.

TRIED TO KEEP AS MUCH OF THE LATER PART OF THE WEEK DRY...GIVEN
BUILDING RIDGE ALOFT.

KEY THING IS WITH CLOSE 5880M RIDGE BUILDING IN LATER IN
WEEK...SURGE OF ABOVE NORMAL 850 HPA TEMPS WITH RELATIVELY LOW PW
VALUES SUGGESTING WARMING UP THURSDAY AND WARMER STILL FRIDAY AND
SATURDAY.

&&

.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
A RIDGE OF HIGH PRESSURE WILL REMAIN NEARLY STATIONARY OVER
PENNSYLVANIA THROUGH SUNDAY...CONTINUING A PERIOD OF VFR
CONDITIONS WITH CLEAR SKIES AND LIGHT WINDS.

EASTERLY FLOW BEGINS TO INCREASE ACROSS THE REGION ON SUNDAY.
CLOUDS INCREASE SUNDAY NIGHT INTO MONDAY AS A DEEP LOW BACKS INTO
THE REGION FROM THE SOUTHEAST. SHOWERY WEATHER RETURNS EARLY
MONDAY WITH MVFR TO IFR CONDITIONS IN LOW CIGS AND VSBY POSSIBLE
IN RAIN SHOWERS ALONG THE LOWER SUSQ TAF SITES /MDT-LNS AND POSS
IPT/.

OUTLOOK...
SUN...VFR WITH A LIGHT...MAINLY EASTERLY WIND.
MON...SCATTERED MVFR CIGS AND VSBYS IN SHOWERS AND ISOLD
THUNDERSTORMS.
MON NIGHT THROUGH WEDNESDAY...MORE WIDESPREAD
REDUCED CIGS AND VSBYS LIKELY IN SHOWERS AND SCTD TSRA.
THU...PRIMARILY VFR. SCT SHRA/TSTM POSS MAINLY SE.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...GRUMM
NEAR TERM...GRUMM
SHORT TERM...GRUMM
LONG TERM...GRUMM/MARTIN
AVIATION...RXR

000
FXUS61 KPBZ 200541
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
141 AM EDT SUN MAY 20 2012

.SYNOPSIS...
HIGH PRESSURE WILL ALLOW FOR DRY AND UNSEASONABLY WARM WEATHER TO
CONTINUE INTO EARLY MONDAY. THE CHANCE OF SHOWERS AND THUNDERSTORMS
WILL RETURN AS A LOW PULLS MOISTURE INTO THE AREA FROM THE SOUTHEAST
AND A FRONTAL BOUNDARY APPROACHES FROM THE WEST.

&&

.NEAR TERM /THROUGH TODAY/...
MID-LEVEL RIDGE WILL CONTINUE ITS HOLD OVER THE REGION FOR ONE
MORE PLEASANT DAY BEFORE PRECIPITATION CHANCES AND TEMPERATURES
CLOSER TO NORMAL RETURN. FOR THE REMAINDER OF THE
OVERNIGHT...NEAR CALM WINDS AND MOSTLY CLEAR SKIES WILL ALLOW FOR
TEMPERATURES TO DROP GENERALLY INTO THE 50S. HOWEVER...SOME CIRRUS
ASSOCIATED WITH TS ALBERTO WILL SPREAD OVERHEAD MAKING FOR A LESS
THAN OPTIMAL RADIATIONAL COOLING NIGHT. THIS SHOULD ALSO KEEP THE
TEMP/DEWPOINT SPREAD FROM REACHING SATURATION AT THE SURFACE
THOUGH SOME PATCHY VALLEY FOG COULD NOT BE RULED OUT.

WHAT IS NOW ESSENTIALLY A FOLD-OVER RIDGE WILL RIDE NORTH OVER THE
UPPER LEVEL CUTOFF LOW OF BOTH ALBERTO AND A LOW SITUATED TO ITS
NORTHEAST...BEST DEPICTED ON IR SATELLITE. A MORE SOUTHERLY WIND
COMPONENT AND GENERALLY CLEAR SKIES SHOULD ALLOW FOR TEMPERATURES
TO REBOUND TO WELL ABOVE NORMAL ONCE AGAIN. HEDGED CLOSEST TO MAV
GUIDANCE THOUGH IT`S NOT UNREASONABLE THAT TEMPERATURES COULD MAKE
IT A DEGREE OR TWO WARMER THAN CURRENT FORECAST. OPTED TO GO WITH
PERSISTENCE TEMPERATURE FORECAST.

&&

.SHORT TERM /TONIGHT THROUGH TUESDAY/...
GFS/ECMWF INDICATE THE RIDGE AXIS BECOMING PINCHED OFF SUNDAY NIGHT
INTO MONDAY AS THE UPPER LOW MOVES INTO VIRGINIA AND A TROUGH MOVES
INTO THE UPPER MIDWEST. THE CLOSED LOW WILL SERVE TO DRAW MOISTURE
INTO THE AREA FROM THE ATLANTIC. WITH THIS IN MIND, THE CHANCE OF
SHOWERS BEGINS SOUTHEAST OF PITTSBURGH ON MONDAY MORNING. IN
ASSOCIATION WITH THE TROUGH, A FRONTAL BOUNDARY WILL CROSS THE OHIO
VALLEY ON MONDAY AFTERNOON. INCREASING MOISTURE AND INSTABILITY
AHEAD OF THIS FEATURE WILL LEAD TO THE CHANCE OF SHOWERS AND
THUNDERSTORMS MONDAY AFTERNOON THROUGH THE EVENING. INCREASED
CLOUD COVERAGE AND COOLER TEMPS ALOFT ASSOCIATED WITH THE LOW
APPROACHING FROM THE SOUTHEAST WILL ALLOW FOR A SLIGHT COOLER DAY
ON MONDAY, WITH HIGH TEMPS AT 5 TO 10 DEGREES ABOVE NORMAL,
RANGING FROM THE LOWER 80S ACROSS EASTERN OHIO TO NEAR 70 ACROSS
THE EASTERN RIDGES.

SOME MODEL UNCERTAINTY ENTERS THE FORECAST IN REGARDS TO THE TROUGH
MOVING INTO THE AREA FROM THE UPPER MIDWEST. ECMWF/NAM SOLUTIONS
MERGE THE UPPER LOW TO THE SOUTHEAST WITH THIS FEATURE INTO A MORE
AMPLIFIED TROUGH ACROSS THE AREA. MEANWHILE, THE GFS MOVES THE UPPER
LOW UP THE EAST COAST AND BRINGS A WEAKER TROUGH ACROSS THE AREA. WITH
THIS UNCERTAINTY IN MIND AND THE SLOW PASSAGE OF A FRONTAL
BOUNDARY, FORECAST IS A BLEND OF THE SOLUTIONS, CONTINUING A
CHANCE OF SHOWERS AND THUNDERSTORMS MONDAY NIGHT INTO TUESDAY.
WITH INCREASED CLOUD COVERAGE WITH SHOWERS AND THUNDERSTORMS,
HIGHS ON TUESDAY WILL BE SLIGHTLY COOLER IN COMPARISON TO THE
WEEKEND AND MONDAY, ALTHOUGH STILL AROUND 5 DEGREES ABOVE NORMAL.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
12Z GFS/00Z ECMWF HAVE DIFFERENT DEPICTIONS IN THE EXTENDED...AND
THEREFORE CONFIDENCE IS BELOW AVERAGE. BOTH MODELS SHOW GENERAL
AGREEMENT THAT THERE WILL BE A NEARLY STATIONARY UPPER LEVEL
LOW/TROUGH NEAR THE CAROLINAS. HOWEVER...MULTIPLE RUNS OF THE GFS
KEEPS THIS FEATURE OVER THE ATLANTIC OCEAN WITH JUST SOME CLOUDS
LOCALLY...WHILE THE ECMWF HAS THE FEATURE INLAND ALONG THE EAST
COAST AND SPREADS RAIN AS FAR WEST AS WEST VIRGINIA AND EASTERN
OHIO. WITH NAEFS AND ECMWF ENSEMBLE KEEPING THE PATTERN A LITTLE
DRIER...HAVE ALSO STUCK WITH A DRIER FORECAST. IF THIS HOLDS...AND
THE GFS FORECAST VERIFIES...THIS PERIOD WILL BE QUITE WARM. GFS
BIAS-CORRECTED GRIDS AND NAEFS METEOGRAMS SUGGEST THAT 90 DEGREES IS
NOT OUT OF THE QUESTION FOR THE START OF THE MEMORIAL DAY WEEKEND.

&&

.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
HIGH PRESSURE WILL KEEP SKIES MOSTLY CLEAR WITH ONLY A FEW CIRRUS.
WINDS BELOW 10 KTS FOR NEXT 24 HOURS.

.OUTLOOK...SUNDAY NIGHT THROUGH THURSDAY...
SUNDAY NIGHT SHOULD REMAIN DRY BEFORE COLD FRONT APPROACHES FROM THE
WEST ON MONDAY WHILE MOISTURE INCREASES FROM THE EAST AS LOW
PRESSURE MOVES UP THE EASTERN SEABOARD. RESTRICTIONS POSSIBLE
THROUGH WEDNESDAY. PRECIPITATION SHOULD THEN SHIFT EAST OF THE AREA
BY WEDNESDAY NIGHT WITH GENERAL VFR THURSDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$