-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KPHI 180620
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
220 AM EDT TUE JUN 18 2013

.SYNOPSIS...
A LOW PRESSURE SYSTEM WILL CONTINUE TO MOVE NORTHEAST THROUGH THE
SAINT LAWRENCE VALLEY TONIGHT. ITS ASSOCIATED COLD FRONT SHOULD
ARRIVE TUESDAY OR TUESDAY NIGHT WITH A WEAK LOW PRESSURE SYSTEM
FORMING ALONG IT. A HIGH PRESSURE SYSTEM WILL THEN BUILD INTO THE
NORTHEAST THE LATTER HALF OF THE WORK WEEK BEFORE SHIFTING
OFFSHORE ON SATURDAY. A WARM FRONT IS FORECAST TO MOVE THROUGH THE
FORECAST AREA ON SUNDAY AND NORTHWARD INTO NEW ENGLAND ON MONDAY.

&&

.NEAR TERM /THROUGH TODAY/...
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STILL TRYING TO FIGURE OUT A BEST FCST SCENARIO:

AS IT STANDS AT 2 AM...LOOKS LIKE NO CONVECTION THRU ABOUT
15Z THEN MODELS START SPEWING AT VARIOUS TIMES OF THE DAY.

WE DO KNOW PWAT WILL INCREASE FROM WHERE IT WAS YDY ..TO ABOUT 1.6
OR 1.7 INCHES AND THAT WIND FIELDS ALOFT SHOULD DECREASE THROUGH
THE DAY SO OTHER THAN A WET MICROBURST...SVR WIND DOESNT SEEM TO
BE A BIG PROBLEM. THERE MIGHT BE A STRONG MESOCYCLONE FOR A SHORT
TIME LATE TODAY ALONG THE BOUNDARY THAT SEEMS TO EVOLVE RAPIDLY
SOUTHWARD THROUGH SOUTHERN NEW JERSEY LATE TODAY.

THE TEMPS DEWS AND WINDS ARE 50 50 BLENDED NAM/GFS 00Z/18 MOS
GUIDANCE AND ADDED A DEGREE FOR LATER THAN MODELED CONVECTION. MAX
TEMPS SHOULD BE IN THE 17-19Z TIME FRAME.

CONSIDERABLE CLOUDINESS TODAY...ESPECIALLY THIS AFTN.

ITS DIFFICULT FOR ME TO BE SURE WHERE CONVECTION WILL BE MOST
WIDESPREAD BUT THE WORDING FOR POSSIBLE HEAVY SHOWERS WILL BE IN
THE FCST.

THE POSSIBILITY EXISTS FOR FFW DEL VALLEY SEWD NEAR THE SFC LOW/CFP
AS IT EVOLVES SOUTHWARD THIS AFTN.
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&&

.SHORT TERM /TONIGHT/...
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CONVECTION MAY STILL BE QUITE ACTIVE THROUGH THE 10 PM TO MIDNIGHT
TIME FRAME THEN GRADUALLY DIE OUT AS NLY FLOW DEVELOPS IN THE
WAKE OF THE SOUTHWARD CFP AND ASSTD SFC LOW MOVING SEAWARD FROM E
OF THE NJ/DE COASTS.

STRATUS IS LIKELY FOR AT LEAST THE S PTN OF THE AREA AS MODELED IN
1000-950 MB RH FIELDS... AS WELL AS SREF PROBS OF CIGS BLO 1000
AND 3000 FT. THE LATTER CIGS MAY BE ARRIVING ON NE FLOW FROM LI
TONIGHT. TIMING ARRIVAL AND CIG HT UNCERTAIN.

TEMPS/DEWS/WINDS ARE 50 50 BLENDED 00Z/18 NAM/GFS MOS GUIDANCE.
-- End Changed Discussion --

&&

.LONG TERM /WEDNESDAY THROUGH MONDAY/...
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HIGH PRESSURE PUSHES INTO THE REGION FOR THE THURSDAY THROUGH
SATURDAY TIME-FRAME, WITH TEMPERATURES RUNNING SLIGHTLY BELOW
NORMAL AND DRY CONDITIONS.

WARM FRONTAL BOUNDARY APPROACH ON SUNDAY BRINGS NEXT POTENTIAL
PRECIPITATION AND BOTH TEMPS AND POPS ON SUNDAY AND MONDAY
FOLLOWED WPC GUIDANCE CLOSELY.
-- End Changed Discussion --

&&

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

THROUGH 12Z...BKN CIRRUS CIGS. PATCHY MVFR VSBY IN FOG.

AFTER 12Z...VFR CIGS WITH CLUSTERS OF IFR SLOW MOVING SHOWERS AND
TSTMS WITH THEIR TORRENTIAL RAINS AND POSSIBLY N-NW G 30-35 KT
THIS AFTN. TIMING AND INTENSITY OF CONVECTION AT ANY TAF LOCATION
IS UNCERTAIN AND THEREFORE THUNDER IS NOT DEFINED IN THE 06Z TAFS.
LIGHT WIND BECOMING SSW FOR A TIME MIDDAY AT 10-15 KT THEN SHIFTING
N LATE.

TONIGHT...LEFTOVER IFR CONDS IN HEAVY SHOWERS AND TSTMS BECOMING
IFR CONDS IN ST/FOG LATE. N WIND BECOMING NNE 10-15 KT LATE.

OUTLOOK...
WEDNESDAY...POCKETS OF MVFR CONDITIONS IN THE MORNING, OTHERWISE
VFR.

WEDNESDAY NIGHT THROUGH SATURDAY...VFR.
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&&

.MARINE...
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SUB-ADVISORY CONDITIONS LOOK TO PERSIST ACROSS OUR WATERS THROUGH
MOST OF TUE NIGHT BUT SCA CONDITIONS MAY DEVELOP VCNTY SANDY HOOK
LATE THIS TUE NIGHT.

OUTLOOK...
RIGHT NOW WE ARE NOT LOOKING AT SCA CONDITIONS TO OCCUR THROUGH
SATURDAY. HOWEVER, THE NORTHEAST FETCH LATE WEDNESDAY INTO
WEDNESDAY NIGHT AND EARLY THURSDAY WILL BRING SEAS UP TO THE 4
FOOT RANGE, SO THIS WILL CONTINUE TO BE MONITORED CLOSELY. WINDS
AND SEAS SUBSIDE AS WE MOVE INTO FRIDAY AND SATURDAY.
-- End Changed Discussion --

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...SZATKOWSKI
NEAR TERM...DRAG 220
SHORT TERM...DRAG 220
LONG TERM...SZATKOWSKI
AVIATION...DRAG/SZATKOWSKI 220
MARINE...DRAG/SZATKOWSKI 220