Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

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000
FXUS61 KPHI 241320
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
820 AM EST MON NOV 24 2014

.SYNOPSIS...
A COLD FRONT SWEEPS OFF THE EAST COAST TONIGHT. HIGH PRESSURE
FOLLOWS LATE TUESDAY. A COASTAL STORM FORMING OFF THE NORTH CAROLINA
COAST WEDNESDAY MORNING MOVES EAST OF NEW ENGLAND BY THANKSGIVING. A
COLD FRONT PASSES THROUGH OUR AREA THURSDAY EVENING AND DRY HIGH
PRESSURE MOVES TO THE CAROLINAS NEXT WEEKEND.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AN AREA OF LOW PRESSURE  WAS LOCATED NR THE GRTLKS.  ITS ASSOCD
WMFNT MOVED THRU OVERNIGHT AND RAIN, SOME MDT TO HVY CAME ALG WITH
IT. PRECIP HAS ENDED ACRS MUCH OF THE DELMARVA AND PORTIONS OF ERN
PA, BUT IT KEPPS REDEVELOPING ACRS ERN NJ AND OVER THE WATERS. SCT
SHWRS POP UP ACR PORTIONS OF DE AT TIMES. WHILE THE OVERALL TREN
OF THE PRECIP IS FOR IT TO DIMINISH, CLEARLY IT WILL NOT BE OVER
BY 12Z AND HAVE RAISED POPS AND EXTENDED THE DURATION FOR A FEW
HOURS, AND DEPENDING ON HOW THINGS PLAY OUT IT MAY NEED TO GO A
BIT LONGER.

WITH THE AREA IN THE WARM SECTOR AND VERY STRONG SWLY FLOW,
TEMPS WILL SOAR INTO THE 70S AND NEAR RECORD, IF NOT RECORD
BREAKING WARMTH IS EXPECTED. IT WILL ALSO BE QUITE BREEZY, WITH
WIND GUSTING UPWARDS OF 35 MPH.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM TUESDAY/...
AS THE AFOREMENTIONED LOW CONTINUES TO MOVE INTO SERN CANADA, IT`S
CDFNT WILL CROSS THE REGION ERLY TONIGHT.  HOWEVER, LATEST GUID
INDICATES IT WILL BE DRY AND POPS HAVE BEEN REMOVED FROM THE FCST.
HIGH PRES FROM THE SW WILL BEGIN TO BUILD IN AND EXPECT A GENL
CLEARING TREND BY MRNG.  IT WILL BE A MILD NIGHT WITH OVERNIGHT LOWS
HIGHER THAN WHAT HIGH TEMPS SHUD BE THIS TIME OF YEAR.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
STILL FOCUSED ON THE WEDNESDAY THROUGH THANKSGIVING TIME FRAME
AND THE POTENTIAL WINTRY IMPACTS TO THE BUSIEST TRAVEL DAY OF THE
YEAR.

NOT TOO MUCH CHANGE FROM THE PREVIOUS FORECAST. MODELS HAVE PRETTY
MUCH STAYED THE COURSE WITH THE TRACK OF THE LOW, COMING INTO
SLIGHTLY BETTER AGREEMENT. THE ECMWF IS STILL THE FURTHEST WEST
AND LEAST PROGRESSIVE, WHILE THE GFS SEEMS TO BE A COMFORTABLE
MIDDLE GROUND, AT LEAST FOR THE TRACK OF THE LOW. BY 00Z
THURSDAY...THE DIFFERENCE IN THE LOCATION OF THE CENTER OF THE LOW
BETWEEN THE GFS AND ECMWF IS ONLY ABOUT 150 MILES. THE ONE
PUZZLING THING WITH THE LATEST MODEL RUNS IS THAT THE GFS CAME IN
CONSIDERABLY COLDER THAN ANY OF THE OTHER MODELS, ODD GIVEN ITS
TRACK OF THE LOW. AS FAR AS PRECIP TYPE, MODEL SOUNDINGS FROM THE
ECMWF, GFS, AND NAM ALL INDICATE EITHER RAIN, RAIN/SNOW, OR SNOW
(ALTHOUGH THE TIMING AND LOCATIONS OF THESE TRANSITIONS ARE STILL
UNCERTAIN BETWEEN THE MODELS...SEE BELOW). THUS, AT THIS POINT
DON/T HAVE ANY CONCERNS FOR FREEZING PRECIP OR ICE ACCUMULATIONS.

LETS TALK TURKEY....FOR SNOW AMOUNTS, STILL EXPECT A PRETTY SHARP
GRADIENT ROUGHLY AROUND THE I 95 CORRIDOR. NORTH AND WEST OF THE
FALL LINE COULD SEE AMOUNTS FROM 2 UP TO 8 INCHES (THE HIGHEST
AMOUNTS SHOULD BE LIMITED TO THE HIGHER TERRAIN IN NW NJ AND THE
POCONOS). EAST OF THE FALL LINE COULD SEE UP TO 2 INCHES. HOWEVER,
COASTAL LOCATIONS WILL LIKELY NOT SEE ANY ACCUMULATIONS AS WITH
THE WATER TEMPERATURE STILL IN THE 50S, THE ONSHORE FLOW SHOULD
KEEP THEM WELL ABOVE FREEZING THROUGH OUT THE EVENT. THE CAVEAT TO
ALL OF THIS IS THAT THE LOCATION OF THE RAIN/SNOW TRANSITION AND
EVEN SNOW RATIOS IS VERY MUCH DEPENDENT ON THE TEMPERATURE, AND
WITH THE PREVIOUSLY MENTIONED COLD OUTLIER OF THE GFS, THERE IS
POOR MODEL AGREEMENT ON THIS ISSUE, SO SNOW AMOUNTS REMAIN
UNCERTAIN.

THE LOW SHOULD BE OVER THE CANADIAN EASTERN MARITIMES BY THURSDAY
MORNING, SO PRECIP SHOULD MOVE OUT QUICKLY BY THEN, IF NOT SOONER.

BEYOND THANKSGIVING...STAYED CLOSE TO WPC GUIDANCE AND THE
PREVIOUS FORECAST AS TO FOCUS ON THE MID WEEK STORM. COLD AIR
SHOULD SETTLE IN OVER THE REGION THROUGH AT LEAST THE END OF THE
WEEK, BEFORE A NORTHERN STREAM LOW PRESSURE SYSTEM MAY BRING
ANOTHER WARM FRONT SUNDAY FOLLOWED BY A COLD FRONT MONDAY.

&&

.AVIATION /13Z MONDAY THROUGH FRIDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.

ITS BEEN A DIFFICULT NIGHT FOR AVIATION.  THE PRECIP AND LOWER CIGS
TOOK LONGER TO MOVE IN, BUT THEN CAME DOWN FASTER THAN FCST.  NOW,
THE PRECIP IS MOVG OUT SOONER THAN EXPECTED, BUT EVEN WHEN IT IS
STILL EXPECT IFR/MVFR TO LINGER BEFORE A RETURN TO VFR LATER.
HOWEVER, WITH THE SYS MOVG OUT SOONER, PERHAPS CONDS WILL IMPROVE
SOONER THAN CURRENTLY FCST.

CURRENTLY, ALL SITES ARE EITHER MVFR OR IFR, AND THERE MAY EVEN BE
SOME LCL LIFR.  RAIN IS ENDING FROM SW TO NE AND WILL CONTINUE TO DO
SO THRU DAYBREAK.  ANY LINGERING PRECIP AFTER DAYBREAK WUD BE OVER
NRN AND ERN AREAS.

THEN CONDS WILL IMPROVE TO VFR.

A GUSTY S TO SW WIND WILL REMAIN WITH US ALL DAY WITH GUSTS NR 30
KTS IN SOME LOCATIONS.

LLWS REMAINS A THREAT THRU THE ERLY MRNG AS WELL WITH VERY STRONG
WINDS OVER 50 KTS ABV THE SFC.

OUTLOOK...
TUESDAY...SHOULD GENERALLY BE VFR ACROSS THE REGION

WEDNESDAY AND WEDNESDAY NIGHT...A COASTAL STORM WILL BRING
WIDESPREAD MVFR OR IFR CEILINGS. REDUCTIONS IN VISIBILITY DUE TO
RAIN ALONG THE COAST (KACY/KMIV), RAIN SNOW MIX CHANGING TO ALL
SNOW IN THE DELAWARE RIVER VALLEY (KTTN KPNE KPHL AND KILG) AND
MOSTLY SNOW KABE AND KRDG. IN ADDITION, EXPECT PERSISTENT
NORTHERLY OR NORTHEASTERLY WINDS FOR GENERALLY THE LATTER HALF OF
THE DAY WITH GUSTS 12-25 KT FROM WEST TO EAST. PRECIPITATION
SHOULD END AS SNOW MOST TAF SITES AT NIGHT EXCEPT POSSIBLY NOT AT
KMIV/KACY.

THANKSGIVING...CONDITIONS SLOWLY RETURN TO VFR AND WINDS SHIFT TO
WESTERLY OR NORTHWEST. THERE COULD BE BRIEF MVFR CONDITIONS IN
SCATTERED SNOW SHOWERS LATER THURSDAY MAINLY JUST N OF KRDG AND
KABE. WINDS MAY GUST TO 25 KT.

FRIDAY...VFR CONDITIONS EXPECTED.

&&

.MARINE...
THE GALE WRNG WILL REMAIN IN EFFECT AS PREV ISSUED THRU LATER THIS
MRNG, THEN A BACK END SCA WILL BE NEEDED, LIKELY FOR THE REMAINDER
OF THE SHORT TERM PD.  HIGH PRES WILL BUILD IN FROM THE SW, BUT THE
P GRADIENT BETWEEN THE HIGH AND THE DEPARTING LOW WILL KEEP GUSTY
WIND OVER THE REGION AND THIS, IN TURN, WILL KEEP THE SEAS ELEVATED.

OUTLOOK...
TUESDAY AND TUESDAY NIGHT...NEAR OR JUST BELOW SCA CONDITIONS WITH
GUSTY WESTERLY WINDS.

WEDNESDAY...GALE CONDITIONS POSSIBLE WITH STRONG NORTHERLY OR
NORTHEASTERLY WINDS.

WEDNESDAY NIGHT...WINDS WILL SLOWLY FALL TO SCA CONDITIONS.

THURSDAY...WINDS ARE EXPECTED TO EVENTUALLY FALL BELOW SCA
CRITERIA BUT ATLANTIC SEAS MAY NOT DROP BELOW 5 FT TIL AT NIGHT.

FRIDAY...POSSIBLE SCA COLD AIR ADVECTION WEST TO NORTHWEST FLOW.

&&

.CLIMATE...
FOR OUR EIGHT CLIMATE SITES, HERE ARE THE RECORD HIGH TEMPERATURES
FOR NOVEMBER 24TH AND THE MOST RECENT YEAR OF OCCURRENCE.

RECORD HIGHS 11/24:

ACY:  72  SET IN 1999
PHL:  71  SET IN 1979
ILG:  73  SET IN 1979
ABE:  69  SET IN 1931
TTN:  71  SET IN 1979
GED:  75  SET IN 1992
RDG:  69  SET IN 1979
MPO:  64  SET IN 1931

RECORD HIGHEST TEMP SO LATE IN THE SEASON (NOV 24)...JUST IN CASE WE
REACH THIS VALUE.

ACY: 77 12/7/1997
PHL: 73 12/7/1998 AND LAST OF SEVERAL
ILG: 75 12/4/1998
ABE: 72 12/29/1984 AND LAST OF SEVERAL
TTN: 76 12/7/1998 (LATTER OF TWO)
GED: 77 12/1/1991 (SHORTER POR)
RDG: 77 12/29/1984
MPO: 67 11/29/1990

REGARDING THE MIDWEEK COASTAL STORM BRINGING SNOW TO A LARGE
PORTION OF OUR REGION, WE HAVE INCLUDED DAILY SNOWFALL RECORDS
BELOW FOR OUR FOUR PRIMARY CLIMATE SITES THAT HAVE A LONG-STANDING
UNBROKEN PERIOD OF RECORD (POR) WITH RESPECT TO HISTORICAL
SNOWFALL DATA.

DAILY SNOWFALL RECORDS:

NOVEMBER 26TH:               NOVEMBER 27TH:       PERIOD OF RECORD:

ACY: TRACE 1977,1957,1955    1.2 INCHES 1978            1874

PHL: 6.0 INCHES 1898         6.9 INCHES 1949,1938       1872

ILG: 0.1 INCHES 1950         4.5 INCHES 1978            1894

ABE: 1.7 INCHES 1925         7.0 INCHES 1938            1922

OTHER COOPERATIVE SITE SHORTER HISTORICAL RECORD CAN BE FOUND AT
THE NWS MOUNT HOLLY WEBSITE UNDER NOW DATA.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...WINTER STORM WATCH FROM WEDNESDAY MORNING THROUGH THURSDAY
     MORNING FOR PAZ054-055.
NJ...WINTER STORM WATCH FROM WEDNESDAY MORNING THROUGH THURSDAY
     MORNING FOR NJZ001-007-008.
DE...NONE.
MD...NONE.
MARINE...GALE WARNING UNTIL 11 AM EST THIS MORNING FOR ANZ430-431-
     450>455.

&&

$$
SYNOPSIS...DRAG
NEAR TERM...NIERENBERG
SHORT TERM...NIERENBERG
LONG TERM...JOHNSON
AVIATION...JOHNSON/NIERENBERG
MARINE...JOHNSON/NIERENBERG
CLIMATE...KLINE/IOVINO/DRAG 820A






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