Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

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FXUS61 KPHI 272341
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
741 PM EDT WED MAY 27 2015

.SYNOPSIS...
HIGH PRESSURE REMAINS OFF THE COAST AND A COLD FRONT WILL MOVE
ACROSS THE AREA THURSDAY INTO THURSDAY NIGHT. HIGH PRESSURE
REESTABLISHES ITSELF OFF THE EAST COAST FRIDAY INTO SATURDAY. A
COLD FRONT IS FORECAST TO MOVE ACROSS THE AREA SATURDAY NIGHT INTO
SUNDAY. HIGH PRESSURE WILL RETURN TO THE NORTHEAST EARLY NEXT WEEK
WHILE THE FRONT STALLS TO THE SOUTH.

&&

.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
THE REMAINING PORTION OF THE SEVERE THUNDERSTORM WATCH WAS ALLOWED
TO EXPIRE AT 23Z.

A BROKEN BAND OF CONVECTION CONTINUES, AS OF 2330Z, ACROSS THE
EASTERN ZONES AND THIS TRAILS DOWN TO THE DELMARVA. THIS APPEARS TO
BE FOCUSED ON AN EARLIER GUST FRONT. WE ARE ANTICIPATING THIS TO
CONTINUE EASTWARD AND IT MAY WEAKEN SOME AS MORE STABLE AIR IS
LOCATED CLOSER TO THE COAST. WE MAY THEN BE ABLE TO MAINTAIN AT
LEAST SOME SHOWERS OVERNIGHT ESPECIALLY ACROSS THE SOUTHERN AREAS AS
A WEAK IMPULSE MAY ARRIVE FROM THE SOUTHWEST.

NO CHANGES WERE MADE TO THE LOW TEMPERATURES ATTM. THE HOURLY GRIDS
WERE ADJUSTED BASED ON THE LATEST OBSERVATIONS, AND THEN THE
LAMP/LAV GUIDANCE WAS USED. THIS INCLUDED ADJUSTMENTS FOR CONVECTIVE
INFLUENCES WHICH CAUSED A MUCH FASTER TEMPERATURE DROP IN MANY
AREAS. DUE TO THE AMPLE LOW-LEVEL MOISTURE ACROSS THE REGION, SOME
PATCHY FOG IS POSSIBLE ESPECIALLY WHERE THE HEAVIER RAIN OCCURRED.

&&

.SHORT TERM /6 AM THURSDAY MORNING THROUGH 6 PM THURSDAY/...
DURING THE DAYTIME THURSDAY, THE PREVIOUSLY MENTIONED SURFACE COLD
FRONT IS EXPECTED TO APPROACH OUR FORECAST AREA DURING THE MORNING
AND GRADUALLY CROSS THE REGION THROUGH THE AFTERNOON TO EVENING.
SIMILAR TO WEDNESDAY, AN INCREASE IN INSTABILITY IS EXPECTED DURING
THE DAY, AND WITH THE APPROACHING FRONT AND A SHORTWAVE ALOFT ACTING
AS LIFTING MECHANISMS, MORE SCATTERED SHOWER/THUNDERSTORM ACTIVITY
IS ANTICIPATED. WE BEGIN POPS A LITTLE EARLIER IN THE DAY, DURING
THE MORNING, FOR OUR WESTERN ZONES. HIGHEST CHANCE POPS, THOUGH, ARE
FOCUSED INTO THE AFTERNOON, BEFORE DECREASING THEN INTO THE EVENING
AS THE FRONT PASSES BY TO THE EAST. MET/MAV GUIDANCE BLENDED WITH
CONTINUITY YIELDS HIGH TEMPERATURES MOSTLY INTO THE MIDDLE AND UPPER
80S FOR THE REGION.

&&

.LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/...
A COLD FRONT WILL BE MOVING ACROSS THE AREA AT THE START OF THE
PERIOD AND COULD HAVE SOME SHOWERS AND TSTMS WITH IT. THE PRECIP
SHOULD BE WINDING DOWN EARLY IN THE PD.

ON FRI, HIGH PRES BUILDS BACK INTO THE REGION, AND DRY CONDS ARE
EXPECTED.

LOW PRES THEN ADVANCES ACRS QUEBEC ON SAT AND ITS ASSOCD CDFNT
WILL APPROACH FROM THE W ON SAT. THERE IS QUITE A BIT OF
UNCERTAINTY AS TO PRECIP CHCS ON SAT. THE GFS IS FASTER WITH THE
FRONT, AND HAS SOME PRECIP, MAINLY N. THE GFS IS SLOWER AND DRIER.
FOR NOW WILL GO WITH LOW POPS. THE GFS HAS CFP SAT NIGHT, WITH THE
ECMWF ON SUN. SHWRS/TSTMS WILL ACCOMPANY FROPA, BUT THERE STILL
REMAIN QUESTIONS AS TO THE TIMING.

THE FRONT THEN STALLS TO THE S OF THE REGION AS HIGH PRES BUILDS
OVER QUEBEC. YESTERDAY, THE MDLS HAD DRIED OUT EARLY NEXT WEEK.
NOW, THEY ARE MAKING IT WETTER. AGAIN, CONFIDENCE IS LOW AS THE
MDLS TRY TO IRON THINGS OUT. LOWERED POPS A BIT YESTERDAY, AND
RAISED THEM A BIT TODAY, BUT DON`T WANT TO MAKE ANY WHOLESALE
CHANGES. ALSO, SOME QUESTIONS REMAIN AS TO AREAL EXTENT AND
PLACEMENT OF THE PRECIP.

BY TUE, THE LOW MOVE NEWD OUT TO SEA AND PRECIP CHCS EITHER MOVE
NWD (GFS) OR DECREASE (ECMWF).

THE FCST IS CONTINGENT ON THE STALLED FRONT AND WHERE IT STALLS,
WHETHER IT WASHES OUT AND IF ANY WAVES DEVELOP UPON IT. THE MDLS
ARE HAVING A DIFFICULT TIME RESOLVING THE FCST EARLY NEXT WEEK AND
AS A RESULT, THE CONFIDENCE IN THIS FCST IS MUCH BELOW AVERAGE.
THERE WILL LIKELY BE SOME PRECIP BEYOND SUN, BUT WHERE, WHEN, AND
TO WHAT EXTENT REMAIN BIG QUESTIONS.

TEMPS LOOK TO START ABV NRML BUT CUD BE BELOW NRML ERLY NEXT WEEK
DEPENDING ON HOW THINGS PLAY OUT.

&&

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

TONIGHT...VFR THROUGH MUCH OF THE NIGHT. THE EXCEPTION IS LINGERING
SHOWERS AND THUNDERSTORMS, WITH THIS ONLY MOSTLY NEAR KMIV AND KACY.
SOME LOW CLOUDS ARE ANTICIPATED TO DEVELOP TOWARD MORNING, THEREFORE
CONTINUED WITH A 1000-1500 FOOT CEILING. SOME FOG SHOULD DEVELOP,
ALTHOUGH THIS MAY BE MORE LIKELY WHERE THE HEAVIEST RAIN OCCURRED.
SOUTHERLY WINDS LESS THAN 10 KNOTS, ALTHOUGH SOME LINGERING
GUSTINESS THIS EVENING MAINLY AT KACY.

THURSDAY...ANY LOW CLOUDS/FOG ARE EXPECTED TO LIFT BY MID MORNING,
THEN VFR. WHILE SOME SHOWERS/THUNDERSTORMS SHOULD DEVELOP DURING THE
DAY /WHICH MAY LOCALLY REDUCE CEILINGS AND VISIBILITIES/, THE TIMING
AND COVERAGE OF THESE IS TOO LOW AT THIS TIME TO INCLUDE IN THE
TAFS. SOUTHWESTERLY WINDS WILL GRADUALLY BECOME MORE WESTERLY AND
INCREASE TO AROUND 10 KNOTS.

OUTLOOK...
THU NIGHT...GENERALLY VFR. SCT SHRA/TSRA EARLY. MDT CONFIDENCE.

FRI...GENERALLY VFR. ISOLATED SHOWERS/THUNDERSTORMS POSSIBLE FOR
WESTERN TAFS.

FRI NIGHT...VFR EARLY, THEN LOWERING CIGS/VSBYS POSSIBLE
OVERNIGHT. MDT CONFIDENCE.

SAT...IFR/MVFR PSBL EARLY, THEN BECOMING VFR DURING THE DAY.
SCATTERED SHRA/TSRA PSBL WHICH MAY REDUCE CIGS/VSBYS. GUSTY
SOUTH- SOUTHWEST WINDS AROUND 20 KNOTS. LOW TO MDT CONFIDENCE ON
TSRA.

SAT NIGHT-SUN...SUB-VFR CONDITIONS POSSIBLE, ESPECIALLY WITH
SHRA/TSRA. LOW TO MDT CONFIDENCE.

&&

.MARINE...
THROUGH THIS EVENING AND TONIGHT, SOME WIND GUSTS TO AROUND 25 KNOTS
ARE EXPECTED, ALONG WITH SOME WAVE HEIGHTS APPROACHING THE 4 TO 5
FOOT RANGE FOR THE COASTAL WATERS. WE THEREFORE MAINTAIN THE CURRENT
SMALL CRAFT ADVISORY THROUGH 10Z THURSDAY. THEREAFTER, WHILE SOME
WIND GUSTS TO AROUND 20 KNOTS MAY STILL OCCUR FOR THE COASTAL
WATERS, MAINLY SUB-SMALL CRAFT ADVISORY CONDITIONS ARE EXPECTED FOR
THE COASTAL WATERS AND FOR DELAWARE BAY THROUGH THURSDAY.

OUTLOOK...
THU-SAT...SUB-SCA CONDS EXPECTED, ALTHOUGH WINDS MAY GUST AROUND
20 KNOTS AT TIMES.

SAT NIGHT...SEAS MAY RETURN TO 5 FEET OR GREATER OVERNIGHT AHEAD
OF AN APPROACHING CDFNT.

SUN...SCA CONDS LIKELY WITH CFP.

&&

.RIP CURRENTS...
BASED ON OFFICE GUIDANCE, WE CONTINUE A MODERATE RISK OF RIP
CURRENTS THROUGH THIS EVENING FOR THE NJ BEACHES UNDER A BREEZY
SOUTH WIND.

&&

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

&&

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


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