Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

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FXUS61 KPHI 250134
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
934 PM EDT SUN APR 24 2016

.SYNOPSIS...
HIGH PRESSURE WILL REMAIN OVER THE EASTERN SEABOARD THROUGH TONIGHT
BEFORE SHIFTING OFFSHORE ON MONDAY. A FRONTAL BOUNDARY IS FORECAST
TO STALL NEAR THE PENNSYLVANIA-NEW YORK BORDER MONDAY THROUGH
TUESDAY MORNING. THE FRONT WILL EVENTUALLY PROGRESS SOUTHWARD
THROUGH THE AREA TUESDAY AFTERNOON AND NIGHT. THE COLD FRONT WILL
MOVE SOUTH OF OUR AREA WEDNESDAY AS HIGH PRESSURE NOSES DOWN FROM
THE NORTHWEST. THE FRONT MAY RETURN BACK NORTHWARD TOWARD THE REGION
THURSDAY AND FRIDAY AS AN AREA OF LOW PRESSURE TRACKS ALONG IT. HIGH
PRESSURE TRIES TO BUILD IN FROM THE NORTHWEST EARLY NEXT WEEKEND
BEFORE ANOTHER LOW PRESSURE SYSTEM APPROACHES FROM THE GREAT
PLAINS.

&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
WINDS WILL BECOME LIGHT AND VARIABLE EARLY...THEN GRADUALLY BECOME
SOUTHWEST IN THE 5 TO 10 MPH RANGE AS SURFACE HIGH PRESSURE
BUILDS OFFSHORE. SKIES ARE EXPECTED TO REMAIN MOSTLY CLEAR THROUGH
THE OVERNIGHT HOURS EXCEPT FOR SOME HIGH CLOUDS IN THE FAR NORTH.
LOW TEMPERATURES TONIGHT WILL RANGE FROM THE UPPER 30S IN THE FAR
NORTH TO THE MID 40S IN THE SOUTH...JUST A TAD BELOW NORMAL FOR
THIS TIME OF YEAR.

SMOKE FROM A WILD FIRE IN MONROE COUNTY PENNSYLVANIA IS BEING
ADVECTED INTO NORTHWESTERN NEW JERSEY, AND RESIDENTS IN THAT AREA
MAY EXPERIENCE HAZY SKIES AND THE SMELL OF SMOKE.

NO SIG CHANGES TO THE FCST WITH THIS UPDATE. INCREASED CLOUDS ACRS
SRN AREAS WITH SOME AI AND ACRS NRN AREAS AS CLOUDS ASSOCD WITH
WARM FRONT ACRS NYS ARE MAKING IT A BIT FURTHER S INTO NERN PA
AND NRN NJ. ALSO HAD TO MAKE SOME MINOR ADJUSTMENT TO TEMPS/DEWPTS
TO BETTER FIT CURRENT OBS.

&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/...
THE SOUTHWESTERLY FLOW WILL BECOME MORE ESTABLISHED AS THE DAY
WEARS ON. THERE COULD BE SOME GUSTS IN THE 15 TO 20 MPH RANGE...
ESPECIALLY IN THE AFTERNOON. MOSTLY CLEAR SKIES IN THE MORNING
WILL GIVE WAY TO INCREASING CLOUDS DURING THE AFTERNOON. A LIGHT
RAIN SHOWER OR SPRINKLE CANNOT BE RULED OUT IN THE FAR NORTH WITH
AN APPROACHING FRONT, AND SLIGHT CHC POPS HAVE BEEN ADDED TO THE
GRIDS ACCORDINGLY. RELATIVE HUMIDITIES WILL ALSO BE ON THE
INCREASE, WITH DEWPOINT TEMPERATURES RISING INTO THE UPPER 40S BY
THE END OF THE DAY, COMPARED TO MID 20S SUNDAY AFTERNOON. HIGHS ON
MONDAY WILL GENERALLY RANGE FROM THE LOW TO MID 70S, SEVERAL
DEGREES ABOVE NORMAL FOR THIS TIME OF YEAR.

&&

.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
A LARGE LOW PRESSURE SYSTEM IS FORECAST TO CUTOFF OVER EASTERN
CANADA THROUGH MUCH OF THE UPCOMING WEEK AND POSSIBLY INTO NEXT
WEEKEND. THE LONG TERM IS LOOKING RATHER ACTIVE WITH THE MID-
ATLANTIC REGION SITUATED ON THE SOUTHWESTERN PERIPHERY OF THE
SYSTEM`S BROAD CYCLONIC FLOW WHILE A WEST-EAST ORIENTED FRONT WAVERS
NEARBY. THE POSITION OF THIS BOUNDARY WILL BE A KEY PLAYER IN
DETERMINING HOW UNSETTLED THE PERIOD TURNS OUT BUT THE ODDS OF OUR
AREA RECEIVING APPRECIABLE RAINFALL ARE HIGHER THAN IN RECENT WEEKS.

A SOUTHWARD SHIFT IN THE DEVELOPMENT OF A WEST-EAST FRONTAL BOUNDARY
WAS NOTED WITH TODAY`S MODEL RUNS COMPARED TO YESTERDAY`S. THIS
FRONT IS EXPECTED TO STALL NEAR OR JUST NORTH OF I-80 CLOSE TO THE
NY-PA AND NY-NJ BORDER MONDAY NIGHT AND TUESDAY MORNING. THE BEST
CHANCES FOR SHOWERS DURING THIS TIME LOOKS TO BE IN OUR FAR NRN
ZONES THAT RESIDE CLOSE TO THE FRONT ALTHOUGH THE WIDESPREAD
OVERRUNNING PRECIP NORTH OF THE BOUNDARY WILL LIKELY STAY TO OUR
NORTH.

AN AREA OF LOW PRESSURE THAT IS CURRENTLY OVER THE NORTHERN PLAINS
IS FORECAST TO TRACK EASTWARD ALONG THE FRONT, PASSING JUST ACROSS
OUR NE PA AND NW NJ EARLY TUESDAY MORNING. NW FLOW BEHIND THE LOW
WILL FINALLY ALLOW THE BOUNDARY TO PUSH SOUTHWARD THROUGH THE AREA
AS A COLD FRONT TUESDAY AFTERNOON AND EVENING. TEMPERATURES WILL BE
HIGHLY DEPENDENT ON THE EXACT POSITION OF THIS FRONT AS WE EXPECT AN
IMPRESSIVE N-S TEMPERATURE GRADIENT ACROSS THE AREA ON TUESDAY WITH
TEMPS ONLY IN THE 60S NORTH OF THE FRONT AND 80S SOUTH. SHOWERS ARE
LIKELY ACROSS THE AREA ON TUESDAY WITH THE BEST CHANCE FOR
THUNDERSTORMS JUST SOUTH OF THE BOUNDARY. THERE IS A RISK FOR SEVERE
THUNDERSTORMS ACROSS OUR SOUTHERN AREAS THAT IS CONDITIONAL ON
SUNSHINE DURING THE PEAK HEATING HOURS THAT WOULD SUFFICIENTLY
DESTABILIZE THE BOUNDARY LAYER IN THE PRE-FRONTAL WARM SECTOR. THE
D3 OUTLOOK FROM SPC HAS INCLUDED PHILA AND ITS SOUTHERN SUBURBS IN A
MARGINAL RISK FOR SEVERE STORMS.

THE FRONT WILL EVENTUALLY MOVE SOUTH OF THE AREA LATE TUESDAY NIGHT
AS HIGH PRESSURE BUILDS IN FROM CENTRAL CANADA. WEDNESDAY WILL
FEATURE DRY CONDITIONS AND NEAR NORMAL TEMPS WITH HIGH PRESSURE
RIDGING INTO OUR AREA.

THE FRONTAL BOUNDARY TO OUR SOUTH IS THEN EXPECTED TO RETURN BACK
NORTHWARD THURSDAY AND FRIDAY AS ANOTHER WAVE OF LOW PRESSURE
ORGANIZES OVER THE FRONT RANGE AND TRACKS EASTWARD ALONG THE
BOUNDARY. IT IS STILL UNCERTAIN HOW FAR NORTH THE FRONT MAKES IT BUT
MODEL CONSENSUS POINTS TO IT MAKE IT CLOSE ENOUGH THAT OVERRUNNING
PRECIP EXPANDS NORTHWARD INTO THE DELMARVA AND PERHAPS SE PA/S NJ BY
THURSDAY AND FARTHER NORTHWARD BY FRIDAY.

HIGH PRESSURE TRIES TO BUILD BACK INTO THE REGION BY SATURDAY BUT
THE FRONT MAY RETURN BACK NORTHWARD LATER IN THE WEEKEND AS YET
ANOTHER WAVE OF LOW PRESSURE APPROACHES FROM THE WEST.

&&

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

VFR CONDITIONS EXPECTED TONIGHT AND MONDAY. WIND WILL DECREASE TO
CALM OR LIGHT AND VARIABLE THIS EVE AND OVERNIGHT AS HIGH
PRESSURE SLIDES OFF THE MID- ATLANTIC COAST. WIND SPEEDS COULD
REACH INTO THE 10 TO 15 KNOT RANGE ON MONDAY AS THE PRESSURE
GRADIENT INCREASES WITH AN APPROACHING FRONT. SKIES SHOULD REMAIN
MOSTLY CLEAR DURING THE OVERNIGHT HOURS, WITH SOME HIGH CLOUDS
POSSIBLE MONDAY AFTERNOON...ESPECIALLY AT THE NORTHERN TAF SITES.

OUTLOOK...

MONDAY NIGHT THROUGH TUESDAY EVENING...SHRA ALONG A FRONT
INITIALLY FAVORED OVER NRN TERMINALS THRU EARLY TUESDAY MORNING.
MOST AREAS TO THE SOUTH OF THESE SHRA WILL REMAIN VFR. NUMEROUS
SHRA AND SCT TSTMS EXPECTED TUESDAY AFTERNOON AND EVENING AS THE
FRONT MOVES SWD. PERIODS OF MVFR WITH TEMPORARY IFR RESTRICTIONS
POSSIBLE WITH THIS CONVECTIVE ACTIVITY.

LATE TUESDAY NIGHT...IMPROVING TO VFR FROM N TO S.

WEDNESDAY AND WEDNESDAY NIGHT...MAINLY VFR.

THURSDAY AND FRIDAY...SHOWERS RETURN BACK INTO THE AREA. CEILING
AND VISIBILITY VALUES MAY DROP INTO THE MVFR CATEGORY, ESPECIALLY
ACROSS OUR SRN TERMINALS.

&&

.MARINE...
SUB-ADVISORY CONDITIONS ARE EXPECTED TONIGHT AND MONDAY ACROSS ALL
THE FORECAST WATERS. A LIGHT NORTHWESTERLY  WIND WILL GRADUALLY VEER TO
A SOUTHWESTERLY DIRECTION AS HIGH PRESSURE MOVES OFFSHORE. THIS
SOUTHWESTERLY FLOW IS EXPECTED TO INCREASE INTO THE 10 TO 15 KNOT
RANGE LATER MONDAY AS A FRONTAL BOUNDARY APPROACHES FROM THE
NORTH.

OUTLOOK...
MONDAY NIGHT INTO TUESDAY...SWLY WINDS INCREASE TO AROUND 20 KT
BUT WE MAY STRUGGLE TO SEE HIGHER GUSTS TO 25 KT IN OUR COASTAL
WATERS. SEAS WILL BUILD TO AROUND 4 TO PERHAPS 5 FT. SCA MAY NEED
TO BE ISSUED BUT HELD OFF ON A 3RD/4TH PERIOD HEADLINE DUE TO THE
MARGINAL SETUP.

TUESDAY NIGHT...SCA CONDITIONS POSSIBLE AS WINDS TURN NELY BEHIND
A COLD FRONT AND MAY GUST TO 25 KT.

WEDNESDAY THROUGH FRIDAY...NO MARINE HEADLINES ARE ANTICIPATED.

&&

.FIRE WEATHER...
WINDS ARE EXPECTED TO DIMINISH THOUGH TONIGHT AS HIGH PRESSURE
MOVES EAST...THEN OFF THE COAST MONDAY MORNING. SOUTHWESTERLY
WINDS ARE EXPECTED TO PICK UP ON MONDAY AFTERNOON INTO THE 15 TO
20 MPH RANGE AS A FRONT APPROACHES FROM THE NORTH. HOWEVER...THIS
SAME SOUTHWESTERLY FLOW WILL PUSH DEWPOINT TEMPERATURES INTO THE
MID TO UPPER 40S, COMPARED TO MID 20S ON SUNDAY, WHICH IN TURN
WILL RAISE RELATIVE HUMIDITY LEVELS INTO THE MID 40S AND LOW 50S
MONDAY AFTERNOON. SO WHILE THE WINDS MAY BE SLIGHTLY STRONGER,
RELATIVE HUMIDITIES WILL BE HIGHER TOO.

&&

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

&&

$$
SYNOPSIS...KLEIN
NEAR TERM...NIERENBERG/MIKETTA
SHORT TERM...MIKETTA
LONG TERM...KLEIN
AVIATION...KLEIN/NIERENBERG/MIKETTA
MARINE...KLEIN/MIKETTA
FIRE WEATHER...



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