Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

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FXUS61 KPHI 271403
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1003 AM EDT WED AUG 27 2014

.SYNOPSIS...
A COLD FRONT WILL APPROACH FROM THE NORTHWEST THIS AFTERNOON
BEFORE MOVING THROUGH THE REGION TONIGHT. HURRICANE CRISTOBAL
WILL PASS WELL EAST OF THE NEW JERSEY AND DELAWARE COASTS LATE
TONIGHT INTO THURSDAY. HIGH PRESSURE WILL THEN BUILD IN FROM THE
WEST ONCE AGAIN FOR THURSDAY INTO SATURDAY. A COLD FRONT WILL THEN
MOVE THROUGH THE AREA FROM THE NORTHWEST SUNDAY INTO MONDAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AT 13Z, SFC COLD FRONT ENTERING WESTERN NY EXTENDED BACK TO THE
SOUTHWEST INTO THE OH VALLEY. THIS FRONTAL BOUNDARY IS ASSOCIATED
WITH A NORTHERN STREAM SHORTWAVE TROUGH THAT IS CURRENTLY LOCATED
BACK OVER THE UPPER MIDWEST/GREAT LAKES REGION. FARTHER
DOWNSTREAM, HURRICANE CRISTOBAL IS LOCATED WELL OFF THE EAST
COAST, ABOUT 500 MILES SOUTHEAST OF FENWICK ISLAND, DE.

THE TRACK OF THIS LOW-AMPLITUDE UPPER SHORTWAVE TROUGH WILL BE
ZONAL AND THUS THE BULK OF THE DYNAMICS IS EXPECTED TO STAY NORTH
OF THE FORECAST AREA. GIVEN THE RATHER WEAK STEERING FLOW SOUTH OF
THIS TROUGH, THE SOUTHERN END OF THE COLD FRONT WILL BE SLOW TO
PROGRESS SOUTH AND EAST TODAY. THE ACTUALLY FRONTAL BOUNDARY MAY
NOT REACH THE POCONOS UNTIL THIS EVE.

STRONG HEATING WILL OCCUR IN PRE-FRONTAL WARM SECTOR OVER THE
AREA TODAY. UNDER THIS SETUP, TRENDED A DEGREE OR TWO WARMER FROM
THE PREVIOUS MAX TEMP FORECAST (WHICH WAS SIMILAR TO THE MAV/MET).
HIGHS IN THE LOWER 90S ARE EXPECTED ALONG THE URBAN I-95 CORRIDOR;
80S ELSEWHERE. MOISTURE IS RATHER LIMITED WITH THIS SYSTEM, BUT A
NARROW PLUME OF LOCALLY HIGHER MOISTURE (WITH DEWPOINTS IN THE
MU60S) ALONG THE FRONT WILL ADVANCE TOWARD THE POCONOS LATE THIS
AFTN. FORECAST SOUNDINGS FOR NORTHEAST PA AND NORTHERN NJ DEPICT A
WEAKLY CAPPED ENVIRONMENT WITH ABOUT 1000-1500 J/KG OF MUCAPE BY
AROUND 21Z. SPC HAS INCLUDED THIS PART OF THE FORECAST AREA IN A 5
PERCENT RISK FOR DAMAGING TSTM WINDS. HOWEVER, THE MORE FAVORABLE
SETUP FOR NOT JUST STRONG STORMS, BUT CONVECTION IN GENERAL, WILL BE
TO THE NORTH AND WEST OF THE CWA DUE TO THE RELATIVELY NORTHERN
TRACK OF THE UPPER TROUGH AND THE FRONT ARRIVING AFTER THE PEAK
HEATING HOURS.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM THURSDAY/...
THE MID LEVEL SHORT WAVE IS EXPECTED TO PASS OVER THE
NORTHEASTERN STATES TONIGHT AND IT SHOULD PUSH A COLD FRONT
THROUGH OUR REGION. THE FRONTAL BOUNDARY IS EXPECTED TO ENTER OUR
NORTHWESTERN COUNTIES THIS EVENING AND IT WILL LIKELY PASS TO OUR
SOUTHEAST LATE TONIGHT.

OUR BEST CHANCE FOR SHOWERS AND THUNDERSTORMS APPEARS TO BE THIS
EVENING, MAINLY ACROSS OUR NORTHWESTERN COUNTIES WHERE SOME
INSTABILITY WILL DEVELOP. MIXED LAYER CAPE VALUES MAY REACH THE
500 TO 1000 J/KG RANGE IN THE POCONOS AND PERHAPS IN ADJACENT
AREAS OF THE LEHIGH VALLEY AND NORTHWESTERN NEW JERSEY. THE LOSS
OF DAYTIME HEATING WILL CAUSE CONDITIONS TO STABILIZE AND ANY
THUNDERSTORMS ARE EXPECTED TO WEAKEN AS THEY MOVE SOUTHEASTWARD
INTO SOUTHEASTERN PENNSYLVANIA AND CENTRAL NEW JERSEY DURING THE
EVENING HOURS.

AN AREA OF CUMULUS AND STRATOCUMULUS ASSOCIATED WITH THE COLD
FRONT SHOULD DROP SOUTHEASTWARD OVER OUR REGION DURING THE NIGHT
ALONG WITH A FEW LINGERING LIGHT RAIN SHOWERS. MOST OF THE CLOUDS
AND ANY PRECIPITATION ARE FORECAST TO BE TO THE SOUTH AND EAST OF
SOUTHERN DELAWARE BY DAYBREAK ON THURSDAY.

TEMPERATURES ARE EXPECTED TO DROP INTO THE 60S TONIGHT IN MOST OF
OUR FORECAST AREA.

THE CENTER OF HURRICANE CRISTOBAL SHOULD PASS MORE THAN 400 MILES
TO OUR SOUTHEAST TONIGHT AND IT WILL HAVE NO IMPACT ON OUR
WEATHER. HOWEVER, IT WILL BRING INCREASED WAVES AND LONG PERIOD
SWELLS TO THE COASTAL WATERS OF DELAWARE AND NEW JERSEY.

&&

.LONG TERM /THURSDAY THROUGH TUESDAY/...
AT THE START OF THE EXTENDD PD, HIGH PRES WAS LOCATED NR THE
GRTLKS AND HRCN CRISTOBAL WAS WELL OFF THE ERN SEABOARD MOVG NE.
CRISTOBAL WILL MAKE ITS CLOSEST APPROACH TO THE AREA ERLY THU
BEFORE PULLING QUICKLY AWAY.

THEN, THE AFOREMENTIONED HIGH PRES WILL BUILD EWD OVER THE REGION
FOR THU INTO SAT BRINGING DRY AND INCREASINGLY WARM WX AS THE H5
RIDGE BUILDS IN.

A WMFNT WILL MOVE TO OUR N ON SAT, BUT DESPITE THIS FEATURE, THE
LATEST GUID HAS TRENDED DRIER, AND HAVE REMOVED ALL POPS, THOUGH A
STRAY SHOWER CAN NOT BE RULED OUT.

BY SUN, THE TEMPS WARM EVEN FURTHER AS THE RIDGE REMAINS IN PLACE
AND THE SWLY FLOW INCREASES. THE MDLS DIFFER SOMEWHAT ON PRECIP
CHCS. THE ECMWF IS MAINLY DRY ON FRI. IT DOES BRING SOME LATE
SHWRS/TSRA TO NRN AND WRN SECTIONS. THE GFS AND CMC HAVE MUCH MORE
PRECIP AROUND. CLEARLY, IN THIS TYPE OF WX PATN THE POTENTIAL FOR
MAINLY DIURNAL SHWRS/TSRA IS THERE, BUT THE ECMWF MAY BE ON TO
SOMETHING WITH ITS SLOWER PROGRESSION, AS THE HIGH IS QUITE
STRONG. FOR NOW, WILL JUST CARRY LOW CHC POPS.

THE BEST CHC OF PRECIP COMES LATER SUNDAY INTO MON WHEN A CDFNT
WILL APPROACH AND CROSS THE AREA. AGAIN, MDLS DIFFER A BIT ON
TIMING. THE GFS IS FASTER (NO SURPRISE) AND IS BASICALLY DRY AFTER
12Z. THE ECMWF LINGERS SOME PRECIP DURG THE DAY ON MON. GENLY THE
ECMWF IS TOO SLOW WITH FROPA TIMING,. BUT AGAIN, IN THIS PATN WITH
THE STRONG HIGH, THE POTENTIAL IS THERE.

THEN, BY MON NIGHT INTO TUE, THE FRONT CLEARS THE AREA, WK HIGH
PRES BUILDS BACK IN AND A DRY DAY IS IN STORE FOR THE LONG RIDE
HOME AFTER THE HOLIDAY WEEKEND.

TEMPS WILL BE AOA NRML THRU THE PD, AND SAT LOOKS TO BE THE BEST
DAY OF THE HOLIDAY WKND, AND SUN COULD END UP BEING NOT ALL THAT
BAD, ESPECIALLY OVER SRN AND ERN AREAS.

&&

.AVIATION /14Z WEDNESDAY THROUGH SUNDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.

VFR FORECAST FOR TODAY. CLOUDS (5-7 FT CIGS) WILL INCREASE AT
RDG/ABE LATE THIS MORNING AND THIS AFTN. A COLD FRONT WILL
APPROACH FROM THE NW. ISO TO PERHAPS SCT SHRA/TSRA MAY DEVELOP IN
VC OF RDG/ABE AFTER 19Z WITH THE BEST CHANCE BETWEEN THE 22Z-02Z
PERIOD. ARRIVAL OF DENSER CLOUD COVER NOT EXPECTED UNTIL TONIGHT
FOR THE OTHER TERMINALS. PRECIP CHANCES DIMINSH BY THE TIME THE
FRONT REACHES PHL/TTN BETWEEN 03-06Z.

A LIGHT AND VARIABLE WIND EARLY THIS MORNING IS FORECAST TO
SETTLE INTO THE SOUTHWEST AROUND 4 TO 8 KNOTS FOR TODAY. A COLD
FRONTAL PASSAGE TONIGHT IS EXPECTED TO CAUSE THE WIND DIRECTION TO
SHIFT TO THE NORTHWEST. SPEEDS WILL LIKELY REMAIN MOSTLY IN THE 4
TO 8 KNOT RANGE.

OUTLOOK...
THU THROUGH SAT...VFR AND DRY WITH HIGH PRESSURE. HIGH
CONFIDENCE. CAN NOT RULE OUT THE SLIGHT CHANCE OF A SHRA/TSRA ON
SAT BUT CHCS ARE TOO LOW TO MENTION ATTM.

SUN...MAINLY VFR. SHRA AND TSRA CHANCES, MAINLY W AS CDFNT
APPROACHES. MDT CONFIDENCE.

&&

.MARINE...
WIND SPEEDS ARE FORECAST TO REMAIN BELOW THE SMALL CRAFT ADVISORY
CRITERION FOR TODAY AND TONIGHT. THE DIRECTION WILL FAVOR THE
SOUTHEAST TO SOUTHWEST TODAY AND IT IS EXPECTED TO SHIFT TO THE
NORTHWEST LATE TONIGHT.

SWELLS FROM HURRICANE CRISTOBAL WILL AFFECT THE COASTAL WATERS OF
DELAWARE AND NEW JERSEY DURING TODAY AND TONIGHT. WAVE HEIGHTS ARE
FORECAST TO INCREASE INTO THE 5 TO 7 FOOT RANGE. A SMALL CRAFT
ADVISORY BEGINS AT 1000 AM FOR OUR OCEAN WATERS FROM OFF ATLANTIC
CITY SOUTHWARD. A SMALL CRAFT ADVISORY BEGINS AT 200 PM FOR OUR
NORTHERN OCEAN WATERS. LONG PERIOD SWELLS OF 12 TO 16 SECONDS WILL
LIKELY CREATE PARTICULARLY ROUGH CONDITIONS AROUND THE INLETS
ALONG THE COASTS OF DELAWARE AND NEW JERSEY.

OUTLOOK...
THU..BASED ON THE LATEST NHC TRACK OF HURRICANE CRISTOBAL, IT
SHOULD MAKE ITS CLOSEST PASS TO US EARLY THU AND THEN MOVE RAPIDLY
AWAY FROM THE AREA BY LATER THU. AS A RESULT, SEAS ARE EXPECTED TO
REMAIN ELEVATED FOR MUCH OF THE DAY AND THE SCA HAS BEEN EXTENDED
INTO THU. BY LATER THU, SEAS SHUD DECREASE AS CRISTOBAL MOVES
AWAY, BUT LESS CONFIDENCE IN JUST HOW QUICKLY THEY SUBSIDE. THE
SCA MAY NEED TO BE EXTENDED A BIT LONGER.

THU NIGHT THROUGH SUN...SEAS WILL CONTINUE TO SUBSIDE EARLY IN
THE PD AND REMAIN BELOW SCA CRITERIA. NO MARINE HEADLINES EXPECTED
THROUGH THE WEEKEND.

&&

.RIP CURRENTS...
LONG PERIOD SWELLS FROM HURRICANE CRISTOBAL WILL RESULT IN A HIGH
RISK OF DANGEROUS RIP CURRENTS ALONG THE COASTS OF DELAWARE AND
NEW JERSEY FOR TODAY INTO TONIGHT. THE ELEVATED THREAT OF
DANGEROUS RIP CURRENTS WILL LIKELY CONTINUE INTO THURSDAY.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...HIGH RIP CURRENT RISK THROUGH THIS EVENING FOR NJZ014-024>026.
DE...HIGH RIP CURRENT RISK THROUGH THIS EVENING FOR DEZ004.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 PM EDT
     THURSDAY FOR ANZ452>455.
     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 2 PM THIS
     AFTERNOON TO 6 PM EDT THURSDAY FOR ANZ450-451.

&&

$$
SYNOPSIS...NIERENBERG/KLEIN
NEAR TERM...IOVINO/KLEIN
SHORT TERM...IOVINO/KLEIN
LONG TERM...NIERENBERG
AVIATION...IOVINO/KLEIN/NIERENBERG
MARINE...IOVINO/NIERENBERG
RIP CURRENTS...IOVINO





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