Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

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000
FXUS61 KPHI 260153
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
953 PM EDT WED MAR 25 2015

.SYNOPSIS...
A WARM FRONT FROM SOUTHWEST PENNSYLVANIA THROUGH WEST VIRGINIA WILL
HEAD NORTHEAST AND CROSS OUR REGION MIDDAY THURSDAY. THEN A COLD
FRONT WILL MOVE ACROSS THE MID ATLANTIC STATES THURSDAY NIGHT. LOW
PRESSURE MAY DEVELOP ON THAT FRONT OFF THE MID ATLANTIC COAST LATE
FRIDAY AND HEAD NORTHEAST WELL OUT TO SEA SATURDAY. HIGH PRESSURE
CENTERED OVER THE GREAT LAKES MIDWEST SATURDAY WILL BUILD TOWARD
THE EAST COAST SATURDAY NIGHT INTO SUNDAY. AN AREA OF LOW PRESSURE
IS EXPECTED TO TRACK TO OUR NORTH MONDAY, PULLING A COLD FRONT
ACROSS THE AREA.

&&

.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
930 PM ESTF: ADJUSTED POPS LOWER TO REFLECT DRYING ALOFT BEHIND THE
BAND OF SHOWERS THAT CROSSED MUCH OF OUR AREA LATE THIS AFTN/EVENING.
NOT THINKING MUCH DRIZZLE OVERNIGHT AND SO REDUCED THAT RISK.
THINK THE FOG WILL HOLD OFF FOR A WHILE SINCE LOW CIGS NOT YET EVIDENT.

TEMPS NEAR WHERE THEY ARE NOW AND NOT EXPECTING MUCH CHANGE OVERNIGHT.
STEADY.

A STRENGTHENING LOW LEVEL SOUTHWESTERLY JET WHICH SHOULD GENERATE
WAA BANDS OF HEAVY SHOWERS AND ISOLATED TSTMS OVER THE DELMARVA
AND FAR SNJ AFTER 09Z/26.

&&

.SHORT TERM /6 AM THURSDAY MORNING THROUGH 6 PM THURSDAY/...
A BAND OR BANDS OF HEAVY SHOWERS/ISOLATED TSTMS SHOULD MOVE NE OFF
THE NJ/DE COASTS DURING THE MORNING AND THEN A BREAK IN THE WX WITH
MORNING FOG/SPOTTY DRIZZLE LIFTING AND DISSIPATING BECAUSE OF WARM
SOUTHWEST WIND GUSTS OF 25 TO 35 MPH DURING THE AFTN.

FOG MAY BECOME QUITE THICK FOR SEVERAL HOURS DURING THE MORNING
DAYLIGHT HOURS AS DEWPOINTS RISE AND THE WARM FRONT LOWERS TO THE
SFC. THE THICKEST FOG ALONG AND N OF I 78 MAY BE DELAYED TIL
MIDDAY.

THE WARM FRONT WILL PROBABLY APPEAR NEAR I-78 NE THURSDAY AFTERNOON.
WINDS WILL TURN MORE SOUTHWEST THROUGH THE MORNING AND A CONTINUED
INFLUX OF WARMER AIR WILL SPREAD ACROSS THE REGION. HIGH TEMPERATURES
THURSDAY AFTERNOON WILL RISE WELL INTO THE 60S AND INTO THE LOWER
70S THROUGH MUCH OF THE FORECAST AREA FROM NEAR PHILADELPHIA ANS
TRENTON SOUTHWARD. NORTH OF THERE...HAVE MY DOUBTS AND WE MAY NEED
TO CONSIDER LOWERING MAX TEMPS SEVERAL DEGREES NORTH OF I-78, OR
AT LEAST DELAY MAX TEMP THERE TIL 6P.

ALONG WITH THE WARM AIR FLOWING INTO THE OUR AREA, WE WILL SEE
INCREASED INSTABILITY AND A POSSIBLY A CHANCE FOR SOME RUMBLES OF
THUNDER LATE IN THE DAY INTO THE EARLY EVENING HOURS. THERE IS
VERY LITTLE MLCAPE ON THURSDAY AND THE SWI STABILIZES AFTER THE
MORNING VALUES WHICH ARE NEAR -2 ALONG THE COASTS.

&&

.LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/...
A COLD FRONT WILL BE MOVING ACROSS THE AREA THURSDAY EVENING INTO
THURSDAY NIGHT. SHOWERS WILL CONTINUE ACROSS THE AREA THROUGH THE
EVENING AND INTO THE OVERNIGHT HOURS, ESPECIALLY AS THE COLD FRONT
MOVES ACROSS THE AREA. THERE WILL REMAIN THE CHANCE FOR A FEW
THUNDERSTORMS BEFORE THE FRONT PASSAGES THROUGH AS THERE REMAINS
SOME WEAK INSTABILITY FORECAST. HOWEVER, ONCE THE FRONT MOVES
THROUGH, THE THREAT FOR THUNDER DIMINISHES, BUT THERE WILL REMAIN
SOME SHOWERS POST FRONTAL. QPF AMOUNTS ARE EXPECTED TO BE AROUND
ONE QUARTER TO ONE THIRD OF AN INCH. BEHIND THE FRONT, IT LOOKS TO
BE COLD ENOUGH ACROSS THE POCONOS FOR SNOW TO OCCUR IF SHOWERS
HOLD ON THERE LONG ENOUGH.

THE FRONT WILL PUSH OFFSHORE BY FRIDAY MORNING, BUT THERE WILL
REMAIN THE CHANCE OF SHOWERS THROUGH FRIDAY AND FRIDAY NIGHT AS
SEVERAL SHORT WAVE/VORTICITY IMPULSES ARE FORECAST TO SLIDE ACROSS
THE AREA IN THE SOUTHWEST FLOW ALOFT. SHOWER ACTIVITY DOES NOT
LOOK VERY ORGANIZED, SO WE KEEP ONLY 20/30 POPS FOR NOW.

ON SATURDAY, AN AREA OF LOW PRESSURE IS EXPECTED TO STRENGTHEN
ALONG THE FRONTAL BOUNDARY TO OUR EAST. HOWEVER, IT IS POSSIBLE
THAT A WEAK SURFACE TROUGH MAY DEVELOP ON THE WESTERN SIDE OF THE
LOW AND MOVE ACROSS OUR AREA. THIS SURFACE TROUGH MAY INTERACT
WITH THE MID/UPPER TROUGH AS IT MOVES ACROSS THE AREA DURING THE
DAY AND CREATE SOME SHOWER ACTIVITY. IT IS POSSIBLE THAT IT MAY BE
COLD ENOUGH FOR SOME SNOW SHOWERS TO OCCUR, ESPECIALLY ACROSS
NORTHERN SECTIONS.

THE LOW AND TROUGH PULL AWAY FROM THE AREA SATURDAY NIGHT, WHILE
HIGH PRESSURE BRIEFLY BUILDS ACROSS THE AREA SATURDAY NIGHT INTO
SUNDAY. THIS WILL BRING DRY WEATHER TO THE AREA FOR THROUGH THE
DAY SUNDAY.

FOR SUNDAY NIGHT INTO MONDAY, AN AREA OF LOW PRESSURE IS FORECAST
TO SLIDE ACROSS THE NORTHEAST, BRINGING A COLD FRONT ACROSS THE
EAST COAST. THIS WILL LEAD TO ANOTHER CHANCE OF ISOLATED/SCATTERED
SHOWERS FOR THE AREA. ONCE AGAIN, IT MAY BE COLD ENOUGH ACROSS
MUCH OF THE AREA FOR SOME SNOW TO OCCUR OVERNIGHT SUNDAY INTO
MONDAY MORNING, BEFORE CHANGING TO RAIN DURING THE DAY. THE LOW
WILL WILL PULL AWAY FROM THE AREA MONDAY NIGHT, ENDING
PRECIPITATION CHANCES.

HIGH PRESSURE IS EXPECTED TO BRIEFLY AFFECT THE AREA ON TUESDAY
INTO TUESDAY NIGHT, THEN SHIFT TO OUR SOUTH ON WEDNESDAY. DRY
WEATHER SHOULD PREVAIL FOR TUESDAY THROUGH EARLY WEDNESDAY.
SHOWERS MAY RETURN LATE WEDNESDAY INTO WEDNESDAY NIGHT AS A WARM
FRONT MAY LIFT ACROSS THE AREA.

&&

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

REST OF TONIGHT...VFR-MVFR CIGS FOR A WHILE. CONDS RAPIDLY LOWER
TO IFR-LIFR IN ST/FOG AND POSSIBLE DRIZZLE BETWEEN 08Z AND 12Z/26.
HEAVY SHOWERS OR A TSTM POSSIBLE VCNTY KMIV AFTER 10Z/26. TSTM
NOT IN THE TAF ATTM. WINDS AT 2000 FT CURRENTLY SSW NEAR 35 KT
WILL BECOME MORE SOUTHWESTERLY OVERNIGHT AND INCREASE TO BETWEEN
40-45 KT, ESPECIALLY SE NJ WHERE MAINTAINED A PERIOD LLWS.
CONFIDENCE BELOW AVERAGE ON DETAILS.

THURSDAY... IFR-LIFR CONDITIONS BEGIN THE DAY IN ST/FOG WITH SCT HEAVY
SHOWERS AND ISOLATED TSTMS MAINLY DELMARVA ACROSS SE NJ EARLY IN
THE DAY. CONDITIONS WILL GRADUALLY IMPROVE AND THERE MAY BE
PERIODS OF VFR, ESPECIALLY DURING MID-LATE AFTERNOON WITH SW WIND
GUSTS OF AROUND 30 KT DEVELOPING DURING THE AFTN MOST TAF SITES
FROM PHL-TTN SOUTH AND EAST EXCEPT NOT KRDG AND KABE WHERE IFR
CONDS MAY REMAIN MOST OF THE DAY. SHOWERS WILL REDEVELOP IN
ADVANCE OF AN APPROACHING COLD FRONT. THERE IS A CHANCE FOR SOME
THUNDER TO OCCUR JUST AHEAD OF AND ALONG THE COLD FRONT LATE IN
THE DAY OR EVENING.

OUTLOOK...

THURSDAY NIGHT...COLD FRONTAL PASSAGE IN THE EVENING. GENERALLY VFR
WITH MVFR/IFR CONDITIONS OCCURRING WITH SHOWERS AND ISOLATED
THUNDERSTORMS.

FRIDAY-FRIDAY NIGHT...MOSTLY VFR EXPECTED. SCATTERED SHOWER
POSSIBLE.

SATURDAY-SATURDAY NIGHT...MOSTLY VFR EXPECTED. SCATTERED SHOWERS
POSSIBLE.

SUNDAY...VFR.

SUNDAY NIGHT-MONDAY...MOSTLY VFR. SCATTERED SHOWERS POSSIBLE.

&&

.MARINE...
SUB-ADVISORY CONDITIONS WILL CONTINUE THROUGH TONIGHT AND INTO EARLY
THURSDAY. SMALL CRAFT ADVISORY CONDITIONS ARE EXPECTED FOR THURSDAY
WITH THE ADVISORY IN EFFECT AT 8AM.

A LOW LEVEL SOUTHWESTERLY JET AROUND 40 TO 50 KNOTS WILL CROSS THE
AREA WATERS TONIGHT. WINDS ON THE OCEAN WILL NOT RESPOND INITIALLY
AS THE WARMER AIR OVER THE COLDER WATERS IS RELATIVELY STABLE AND
DOES NOT PROMOTE GOOD MIXING OF THE HIGHER WINDS TO THE SURFACE.
WINDS WILL REMAIN OUT OF AN EAST TO SOUTHEAST DIRECTION AND SPEEDS
WILL GENERALLY BE AROUND 10 KNOTS OR LESS THROUGH TONIGHT WITH AND
INCREASE TO AROUND 10 TO 15 KNOTS BY THURSDAY MORNING. WINDS WILL
CONTINUE TO INCREASE AND WE WILL SEE SUSTAINED WINDS AROUND 20 TO 25
KNOTS THURSDAY MORNING WITH GUSTS UP TO 30 KNOTS ON THE WATERS.

WAVE HEIGHTS WILL REMAIN AROUND 2 FEET TONIGHT, INCREASING TO 2 TO 4
FEET BY THURSDAY MORNING. WAVE WILL CONTINUE TO INCREASE THROUGH THE
DAY, BECOMING 4 TO 6 FEET BY THURSDAY AFTERNOON.

OUTLOOK...

THURSDAY NIGHT...SMALL CRAFT ADVISORY REMAINS IN EFFECT WITH
ELEVATED WINDS AND SEAS. COLD FRONTAL PASSAGE EXPECTED DURING THE
EVENING WITH A WIND SHIFT FROM SOUTHWEST TO NORTHWEST OVERNIGHT.

FRIDAY...SMALL CRAFT ADVISORY CONDITIONS REMAINS OF THE OCEAN DUE
TO ELEVATED SEAS.

FRIDAY NIGHT...WINDS MAY INCREASE BACK TO SMALL CRAFT ADVISORY
LEVELS OVERNIGHT.

SATURDAY-SATURDAY NIGHT...WINDS AND SEAS MAY REMAIN NEAR SMALL CRAFT
ADVISORY LEVELS.

SUNDAY...CONDITIONS EXPECTED TO DROP BELOW SMALL CRAFT ADVISORY
LEVELS.

SUNDAY NIGHT-MONDAY...WINDS AND SEAS INCREASE OVERNIGHT TO AT LEAST
SMALL CRAFT ADVISORY LEVELS, POSSIBLY NEAR GALE FORCE.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 8 AM THURSDAY TO 6 PM EDT FRIDAY FOR
     ANZ450>455.
     SMALL CRAFT ADVISORY FROM 8 AM THURSDAY TO 8 AM EDT FRIDAY FOR
     ANZ430-431.

&&

$$
SYNOPSIS...DRAG/ROBERTSON
NEAR TERM...DRAG 954
SHORT TERM...DRAG/MEOLA 954
LONG TERM...ROBERTSON
AVIATION...DRAG/ROBERTSON/MEOLA 954
MARINE...DRAG/ROBERTSON/MEOLA 954



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