Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

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000
FXUS61 KPHI 262325
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
625 PM EST WED NOV 26 2014

.SYNOPSIS...
A COASTAL LOW WILL QUICKLY MOVE TO THE NORTHEAST TONIGHT. HIGH
PRESSURE IS FORECAST TO BUILD ACROSS THE EAST COAST FRIDAY INTO
EARLY SATURDAY, BEFORE SQUEEZING TO THE SOUTH SATURDAY NIGHT. A COLD
FRONT IS EXPECTED TO SAG DOWN ACROSS THE AREA SUNDAY NIGHT, BEFORE
SLOWLY MOVING THROUGH THE AREA MONDAY INTO MONDAY NIGHT. HIGH
PRESSURE WILL THEN RETURN TO THE NORTHEAST FOR TUESDAY, FOLLOWED BY
ANOTHER POTENTIAL FRONTAL SYSTEM WEDNESDAY.

&&

.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
THE 23Z OBJECTIVE SURFACE ANALYSIS SHOWS THE CENTER OF THE LOW
WAS EAST OF TEXAS TOWER AND PROBABLY NEAR 997 MB. THE COASTAL LOW
WILL CONTINUE TO DEEPEN OFF THE MID- ATLANTIC COAST AS IT MOVES
QUICKLY NORTHEASTWARD, PASSING JUST EAST OF LONG ISLAND AND CAPE
COD THIS EVENING.

THERE IS ONE LAST FGEN BAND THAT IS WORKING THROUGH OUR CWA. WE
UPPED POPS IN THE NEAR TERM REFLECTING THIS. OUR CWA IS LOSING
MOISTURE ABOVE 10000 TO 15000 AS MID LEVEL DRYING IS WORKING INTO
OUR CWA. WHERE IT IS SNOWING, THE SNOW IS MAINLY RIME OR NEEDLES
AS THE DENDRITIC OMEGA IS ALSO GONE. ACROSS PARTS OF NJ AND DE,
THE DRY AIR IS DEEPER AND FORECAST SOUNDINGS ARE SUGGESTING NO ICE
FOR SNOW. SOME OF THE ASOS SNOW OBSERVATIONS SOUTHEASTERN CWA (AS
OUR OFFICE WITH VAY) MAY BE DUE TO THE SMALL WATER DROPLET SIZE.

THUS, MODEL QPF WHICH ARE MODEST FOR THE EVENING LOOK OK. THE HRRR
HAS THIS BANDED AREA PRECIPITATING ITSELF OUT OVER THE NEXT COUPLE
OF HOURS AND BASED ON THE FORMATION OF THE TROWAL OVER NY STATE
AND THE DEPARTURE OF ANY QVEC OR FGEN FORCING LOOK REASONABLE.

WITH THE LAST BAND EXITING NRN DELMARVA, WE ARE CANCELING THAT
ADVISORY. WE WILL LEAVE OTHER HEADLINES IN PLACE FOR THIS FINAL
BAND.

WE WILL LIKELY BE ABLE TO CANCEL WINTER HEADLINES FROM SOUTH TO
NORTH A FEW HOURS EARLIER. PRECIPITATION WILL END FROM SOUTH TO
NORTH THIS EVENING. TEMPERATURES WILL REMAIN STEADY OR MAY EVEN
RISE A BIT THIS EVENING ONCE THE PRECIPITATION ENDS. DO NOT EXPECT
TEMPERATURES TO FALL MORE THAN A FEW DEGREES OVERNIGHT AS CLOUDS
LINGER ACROSS THE AREA.

&&

.SHORT TERM /6 AM THURSDAY MORNING THROUGH 6 PM THURSDAY/...
THE COASTAL LOW THAT IS IMPACTING THE AREA TODAY WILL TRACK
NORTHEASTWARD INTO THE CANADIAN MARITIMES ON THURSDAY. THE TRAILING
SURFACE TROUGH/COLD FRONT IS FORECAST TO MOVE OFF THE NJ COAST AND
THROUGH THE DELMARVA. THE 12Z GFS AND ECMWF HINT AT A WEAK WAVE OF
LOW PRESSURE DEVELOPING ON THE LEE SIDE OF THE BLUE RIDGE MOUNTAINS
BY 12Z THURSDAY. THIS LOW WOULD THEN MOVE EAST-NORTHEAST OFF THE NC
COAST DURING THE AFTERNOON. A FEW SHOWERS NORTH OF THIS LOW MAY
BRUSH THE DELMARVA DURING THE DAY. BOUNDARY LAYER THERMAL PROFILES
MARGINALLY SUPPORTIVE OF A SNOW PERHAPS MIXING IN WITH THE RAIN BUT
NO ACCUMULATIONS EXPECTED WITH SURFACE TEMPERATURES NEAR 40F.

OTHERWISE, CLOUDS WILL LINGER ACROSS THE AREA FOR MOST OF THE DAY
WITH THE UPPER TROUGH PROGRESSING EASTWARD ACROSS THE MID ATLANTIC
AND NORTHEAST STATES. USED A BLEND OF THE MAV/MET GUIDANCE FOR
TEMPS, GIVING US HIGHS IN THE 30S FROM I-95 WEST AND LOWER 40S TO
THE EAST.

&&

.LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/...
THURSDAY NIGHT IS EXPECTED TO BE DRY, WITH THE EXCEPTION OF A FEW
LAKE EFFECT SNOW SHOWERS THAT MAY MAKE THEIR WAY ACROSS OUR NORTHERN
AREAS. THEY WOULD BE QUITE ISOLATED, SO WE ONLY CARRY 20 POPS.

ON FRIDAY, HIGH PRESSURE BEGINS TO BUILD ACROSS THE EAST COAST,
BEFORE SQUEEZING TO OUR SOUTH AND EAST BY SATURDAY NIGHT. MODEL
GUIDANCE IS INDICATING A COUPLE OF SHORT WAVE/VORTICITY IMPULSES
SLIDING ACROSS THE AREA, ALONG WITH AN INCREASE IN MOISTURE ALOFT
ACROSS THE NORTHERN AREAS. THERE IS SOME TIMING DIFFERENCES, BUT WE
WILL KEEP A SLIGHT CHANCE OF SHOWERS ACROSS OUR NORTHWESTERN ZONES
WHERE THEY HAVE A BETTER CHANCE OF SQUEEZING OUT SOME MOISTURE.
ANYTHING THAT WOULD FALL IS EXPECTED TO BE LIGHT.

ON SUNDAY, WE WILL BE IN BETWEEN THE HIGH TO OUR EAST AND AN
APPROACHING COLD FRONT. ANOTHER WEAK SHORT WAVE/VORTICITY IMPULSE
AND MOISTURE PLUME ALOFT SPREAD ACROSS THE NORTHERN HALF OF THE AREA
SUNDAY, SO THERE REMAINS A SLIGHT CHANCE OF SHOWERS SUNDAY.

A FRONTAL BOUNDARY IS EXPECTED TO APPROACH THE AREA SUNDAY NIGHT
INTO MONDAY. THERE IS SOME DIFFERENCES WITH THIS BOUNDARY AS THE GFS
IS FAST THAN THE ECMWF AND CANADIAN, AND DRIES THE PRECIP OUT
SIMILAR TO THE CANADIAN, BUT UNLIKE THE ECMWF WHICH KEEPS SOME LIGHT
PRECIP ACROSS THE AREA. WE WILL CONTINUE WITH CHANCE/SLIGHT CHANCE
POPS, WITH THE HIGHEST ACROSS THE NORTHERN AND WESTERN AREAS WHERE
THE PRECIP WOULD IMPACT FIRST BEFORE DRYING OUT.

THE FRONT SHOULD PUSH TO OUR SOUTH AS HIGH PRESSURE BUILDS ACROSS
THE NORTHEAST TUESDAY, BUT THERE COULD BE SOME LIGHT PRECIP THAT
LINGERS ACROSS THE SOUTHERN AREAS IF THE FRONT STALLS CLOSER TO THE
AREA.

ANOTHER FRONTAL BOUNDARY IS EXPECTED TO AFFECT THE AREA AROUND NEXT
WEDNESDAY. HOWEVER, THERE IS A QUESTION OF WHETHER THE FRONT SURGES
THROUGH LIKE THE ECMWF, OR GETTING HUNG UP TO OUR NORTH LIKE THE
GFS. WE WILL INTRODUCE A CHANCE/SLIGHT CHANCE OF POPS ACROSS THE
AREA AS BOTH ARE SHOWING THE POTENTIAL FOR PRECIP.

&&

.AVIATION /23Z WEDNESDAY THROUGH MONDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.

THIS AFTERNOON - THIS EVENING...IFR TO LIFR CONDITIONS ARE EXPECTED THIS
AFTERNOON WITH MULTIPLE PRECIPITATION TYPES. RDG AND ABE WILL BE
THE ONLY SITES TO REMAIN SNOW THROUGHOUT THE AFTERNOON WHILE
ILG/PHL/TTN/PNE WILL BOUNCE AROUND QUITE A BIT BETWEEN
RAIN/SNOW...ACY/MIV SHOULD REMAIN MOSTLY RAIN. EXPECTING A HEAVIER
BAND OF PRECIPITATION TO MOVE IN FROM THE SOUTHWEST THIS AFTERNOON
WHICH COULD ALLOW FOR MODERATE TO HEAVY SNOW UP THE I-95 CORRIDOR,
THOUGH IT SHOULD BE RATHER SHORT LIVED. GUSTY NORTHERLY WINDS,
UPWARDS OF 30 KNOTS, ARE EXPECTED.

TONIGHT...IFR TRENDING TO MVFR AND POSSIBLY VFR LATE. LATER THIS
EVENING WE SHOULD SEE THE PRECIPITATION BEGIN TO SLOW DOWN AS THE
SURFACE LOW MOVES TO OUR NORTHEAST. THERE IS A CHANCE THAT WE
COULD SEE ANOTHER CHANGE OVER TO A LIGHT RAIN/DRIZZLE AS WELL
WHICH SHOULD HELP TO IMPROVE CONDITIONS A BIT...WINDS BACK TOWARDS
THE NORTHWEST LATE.

TOMORROW...VFR CONDITIONS EXPECTED. WINDS TURN MORE WESTERLY WITH MOSTLY
DRY CONDITIONS EXPECTED. COULD BE SOME ISOLATED SHOWERS AT ILG/MIV/ACY
DURING THE AFTERNOON HOURS.

OUTLOOK...
THURSDAY NIGHT...MOSTLY VFR.

FRIDAY-MONDAY...MOSTLY VFR. WIND GUSTS 15-20 KNOTS EACH DAY; NW
FRIDAY, SW SATURDAY & SUNDAY, AND NW ON MONDAY.

&&

.MARINE...
GALE WARNING REMAINS IN EFFECT FOR THE ATLANTIC WATERS THROUGH 10 PM
WITH WINDS 30-35 KT. INCREASED SEAS TO 7-12 FT AS WELL. BUOY 44009 IS
REPORTING 11 FT WAVES. THERE IS ALSO A POTENTIAL FOR A FEW HIGHER
GUSTS IN EXCESS OF 40 KT LATE THIS AFTERNOON IN THE FAR EASTERN PART
OF ATLANTIC WATERS IF A GRAVITY WAVE MOVES CLOSE ENOUGH TO THE COAST.

WINDS SHOULD DIMINISH BY MIDNIGHT, BUT SEAS WILL LIKELY REMAIN ABOVE
5 FT ON THE COASTAL WATERS OVERNIGHT. THUS, ONCE WINDS DROP BELOW
GALE CONDITIONS, AN SCA WILL LIKELY BE NEEDED.

SUB-SCA CONDITIONS FOR THURSDAY.

OUTLOOK...
THURSDAY NIGHT...WINDS ARE EXPECTED TO BE BELOW SMALL CRAFT ADVISORY
LEVELS, BUT SEAS MAY REMAIN ELEVATED INTO THURSDAY NIGHT.

FRIDAY-FRIDAY NIGHT...SUB-SMALL CRAFT ADVISORY CONDITIONS EXPECTED
AS HIGH PRESSURE BUILDS OVER THE AREA.

SATURDAY-SUNDAY...NEAR SMALL CRAFT ADVISORY CONDITIONS POSSIBLE AS
HIGH PRESSURE PUSHES TO OUR SOUTH AND COLD FRONT APPROACHES LATE ON
SUNDAY NIGHT.

&&

.CLIMATE...
HERE ARE THE DAILY SNOWFALL RECORDS FOR OUR 4 SNOW CLIMATE SITES
FOR NOVEMBER 26.

ACY - TRACE IN 1977, 1957, 1955

PHL - 6.0 INCHES IN 1898

ILG - 0.1 INCHES IN 1950

ABE - 1.7 INCHES IN 1925.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...WINTER STORM WARNING UNTIL 10 PM EST THIS EVENING FOR PAZ054-
     055-060>062-101-103-105.
     WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR
     PAZ070-071-102-104-106.
NJ...WINTER STORM WARNING UNTIL 10 PM EST THIS EVENING FOR NJZ001-
     007>010.
     WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR
     NJZ012-015.
DE...NONE.
MD...NONE.
MARINE...GALE WARNING UNTIL 10 PM EST THIS EVENING FOR ANZ431-450>455.
     SMALL CRAFT ADVISORY UNTIL 10 PM EST THIS EVENING FOR ANZ430.

&&

$$
SYNOPSIS...ROBERTSON
NEAR TERM...GIGI/KLEIN
SHORT TERM...KLEIN
LONG TERM...ROBERTSON
AVIATION...HEAVENER/ROBERTSON
MARINE...KLEIN/ROBERTSON
CLIMATE...





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