Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

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FXUS61 KPHI 021627
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1227 PM EDT SUN AUG 2 2015

.SYNOPSIS...
HIGH PRESSURE EXTENDING OVER THE OHIO VALLEY TO MID ATLANTIC REGION
WILL GRADUALLY MOVE SOUTHEAST THROUGH MONDAY. A COLD FRONT FROM THE
GREAT LAKES IS FORECAST TO CROSS OUR REGION LATE MONDAY INTO EARLY
TUESDAY, EVENTUALLY STALLING JUST SOUTH OF OUR AREA WEDNESDAY AND
THURSDAY AS A WAVE OF LOW PRESSURE MOVES ALONG IT. THIS STALLED
FRONTAL BOUNDARY SHOULD REMAIN JUST SOUTH OF THE DELMARVA PENINSULA
INTO FRIDAY AND SATURDAY AS ADDITIONAL WAVES OF LOW PRESSURE MOVE
ALONG IT.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
NO MAJOR CHANGES NEEDED TO THE FORECAST. ONLY A FEW HOURLY GRID
CHANGES AND IN INCREASE IN CLOUD COVER AS SOME CUMULUS BUILD UP
HAS BEGUN TO OCCUR AND SOME CIRRUS MOVING NORTHWARD FROM THE
SOUTH. OTHERWISE, WE CONTINUE TO EXPECT A DRY FORECAST TODAY.

THERE LOOKS TO BE A CAP RIGHT AROUND 700MB THIS AFTERNOON WHICH
SHOULD HELP TO KEEP US DRY TODAY...ESPECIALLY WITH DEWPOINTS
REMAINING ON THE DRIER SIDE AS PWATS REMAIN WELL BELOW NORMAL.
AMPLE SUNSHINE SHOULD ALLOW FOR ANOTHER CLOSE TO IF NOT LOW-90S
KIND OF DAY. LIGHT SOUTHWESTERLY FLOW SHOULD ALLOW FOR BETTER
SEABREEZE INLAND PENETRATION AND POSSIBLY BAY/RIVER BREEZE CLOSE
TO ILG/PHL.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...
ANOTHER MOSTLY CLEAR NIGHT IS EXPECTED WITH HIGH PRESSURE CONTINUING
TO PASS OVERHEAD AND OUT TO SEA LATE TONIGHT. WEAK LOW-LEVEL
MOISTURE ADVECTION COMMENCES WITH LIGHT SOUTHERLY WINDS IN
PLACE...DEWPOINTS REMAIN ON THE DRIER SIDE NORTH OF DELMARVA LATE
TONIGHT. COULD BE SOME POCKETS OF GROUND FOG ACROSS SOUTHERN NEW
JERSEY AND DELMARVA LATE TONIGHT. TEMPERATURES DIP BACK INTO THE LOW
TO MID-60S WITH GOOD RADIATIONAL COOLING CONDITIONS EXPECTED.

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...
A MORE ACTIVE, UNSETTLED PATTERN IS EXPECTED THROUGH MUCH OF THE
LONG TERM PERIOD. A COLD FRONT WILL APPROACH OUR REGION FROM THE
NORTHWEST, AROUND THE GREAT LAKES, DURING MONDAY. THE COLD FRONT IS
PROGGED TO GRADUALLY PASS THROUGH THE REGION FROM LATE MONDAY INTO
EARLY TUESDAY. WHILE TIMING AND COVERAGE OF SHWR/TSTORM ACTIVITY
ASSOCIATED WITH THIS BOUNDARY AND SOME SHORTWAVE ENERGY ALOFT STILL
REMAINS A LITTLE UNCERTAIN, IT DOES APPEAR THAT A FEW STRONGER
STORMS WITH GUSTY WINDS ARE POSSIBLE AS THERE IS ADEQUATE MODELED
CAPE AND SHEAR. INTO TUESDAY, THE COLD FRONT IS PROGGED TO BE
PASSING SOUTH AND EAST OF OUR AREA, EVENTUALLY STALLING OFFSHORE.
WHILE OVERALL COVERAGE OF ANY POP-UP SHWRS/TSTORMS LOOKS TO BE LOW,
SOME SLIGHT CHANCE POPS HAVE BEEN KEPT AS SOME MODEL GUIDANCE SHOWS
ANOTHER POSSIBLE SHORTWAVE ALOFT PERHAPS MOVING OVER THE REGION
LATER IN THE DAY.

THIS OVERALL PATTERN LOOKS TO CONTINUE THROUGH WEDNESDAY AND
THURSDAY, AND ALSO INTO THE FRIDAY/SATURDAY TIMEFRAME, WITH THE
STALLED FRONTAL BOUNDARY REMAINING NEAR OR JUST SOUTH OF THE
DELMARVA. TIMING AND COVERAGE OF SHWR/TSTORM ACTIVITY REMAINS HIGHLY
UNCERTAIN AT THIS EXTENDED RANGE, AND WHILE A COMPLETE WASHOUT IS
NOT LIKELY IN THE MID TO LATE WEEK PERIOD, BOTH THE GFS AND ECMWF
SHOW THE POTENTIAL FOR A WAVE OF LOW PRESSURE TO DEVELOP AND MOVE
ALONG THE STALLED BOUNDARY IN THE THURSDAY TIMEFRAME AND ALSO
POSSIBLY FOR FRIDAY INTO SATURDAY. WE THEREFORE HAVE FOCUSED SOME
HIGHER CHANCE POPS FOR THE AREA ON THURSDAY. OTHERWISE WITH THE
CONTINUED UNCERTAINTY THROUGH THIS EXTENDED RANGE, WE MOSTLY USED A
BLEND OF WPC GUIDANCE WITH CONTINUITY FOR TEMPERATURES, POPS, AND
WINDS.

&&

.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.

TODAY...VFR. LIGHT AND VARIABLE WINDS TO START THE TODAY BEFORE THEY
PICK MORE OF A SOUTHWESTERLY DIRECTION. SHOULD SEE SEABREEZE AND BAY
BREEZE CIRCULATIONS AFFECT ACY AND ILG FOR A TIME THIS AFTERNOON.

TONIGHT...VFR. WINDS BACK MORE TOWARDS THE SOUTH LATE THIS EVENING
BUT DECREASE BECOMING LIGHT AND VARIABLE ONCE AGAIN WITH HIGH
PRESSURE OVERHEAD.

OUTLOOK...
MONDAY...POSSIBLE PATCHY MVFR CONDITIONS IN FOG EARLY, MAINLY AT THE
MORE RURAL TERMINALS. THEN PRIMARILY VFR CONDITIONS THROUGH THE DAY,
BUT A LOWERING TO MVFR WITH CIG/VSBY RESTRICTIONS IN SCATTERED
SHWRS/TSTORMS FROM LATE-DAY INTO THE NIGHT.

TUESDAY...MOSTLY VFR CONDITIONS. ISOLATED TO PERHAPS SCATTERED
SHWRS/TSTORMS ARE POSSIBLE.

WEDNESDAY...MAINLY VFR CONDITIONS.

THURSDAY...MVFR CONDITIONS POSSIBLE DURING SHWRS AND TSTORMS.

&&

.MARINE...
SUB-SCA CONDITIONS EXPECTED TODAY AND TONIGHT. SEAS REMAIN AROUND 3
FEET AS WINDS SLACKEN THIS AFTERNOON AND REMAIN PRIMARILY OFFSHORE.
HIGH PRESSURE OVERHEAD TONIGHT WILL ALLOW FOR EVEN MORE TRANQUIL
CONDITIONS TO SET IN.

OUTLOOK...
MONDAY AND TUESDAY...CONDITIONS MAY APPROACH SCA CRITERIA. SOME WIND
GUSTS COULD BE AROUND 25 KNOTS PLUS WITH SEAS INCREASING FOR THE
COASTAL WATERS LATE MONDAY INTO EARLY TUESDAY ASSOCIATED WITH A COLD
FRONT PASSAGE.

WEDNESDAY AND THURSDAY...MOSTLY SUB-SCA CONDITIONS; HOWEVER, A
STALLED FRONT AND A WAVE OF LOW PRESSURE MOVING ALONG IT COULD
ENHANCE SEAS AND/OR WINDS FOR THE COASTAL WATERS, ESPECIALLY INTO
THURSDAY.

&&

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

&&

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



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