Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

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FXUS61 KPHI 141544 CCA
AFDPHI

AREA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1043 AM EST SUN DEC 14 2014

.SYNOPSIS...
BROAD HIGH PRESSURE TO OUR WEST WILL GRADUALLY BUILD INTO OUR REGION
THROUGH MONDAY, BEFORE EXITING OFFSHORE LATER MONDAY NIGHT. A WARM
FRONT IS EXPECTED TO LIFT THROUGH THE AREA TUESDAY, FOLLOWED BY A
COLD FRONT TUESDAY NIGHT INTO WEDNESDAY. MORE HIGH PRESSURE TO OUR
WEST WILL THEN SLOWLY BUILD EASTWARD INTO OUR REGION THROUGH THE END
OF THE WEEK. BY SATURDAY, A LOW PRESSURE SYSTEM MAY APPROACH THE
AREA FROM THE SOUTHWEST.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
FORECAST PRODUCTS HAVE BEEN UPDATED TO ADD A FEW SNOW/RAIN SHOWERS
ACROSS THE FAR NORTHERN AREAS.

A CONTINUATION OF THE PRESENT WEATHER LOOKS LIKE THE BEST FORECAST
AT THIS POINT AS FEW BREAKS HAVE DEVELOPED IN THE SOLID OVC ACROSS
THE REGION. LATER THIS AFTERNOON...AS THE SFC HIGH NEARS...SOME BREAKS
WILL PROBABLY DEVELOP IN THE CLOUDS. WE HAVE KEPT HIGH TEMPS WERE
THEY WERE BEFORE...OR A DEGREE LOWER IN A FEW PLACES.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...
THE HIGH IS VIRTUALLY OVERHEAD TONIGHT AND WE MAY FINALLY SEE SOME
CLEARING.  THERE WILL STILL BE SOME WIND WHICH WILL KEEPS TEMPS FROM
BOTTOMING OUT.  MOS GUID GENLY REASONABLE AND ACCEPTED.

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...
A RELATIVELY QUIET START TO THE LONG TERM BEFORE A SOMEWHAT ACTIVE
PATTERN ENSUES THIS WEEK AND ESPECIALLY LOOKING AHEAD TO NEXT
WEEKEND. SURFACE HIGH PRESSURE AND MID-LEVEL RIDGING ACROSS THE MID
ATLANTIC ON MONDAY WILL YIELD A PRECIP-FREE DAY WITH LIGHT WINDS AND
NEAR TO SLIGHTLY ABOVE AVERAGE DAYTIME TEMPERATURES. WE MAINLY WENT
WITH A MET/MAV GUIDANCE BLEND FOR MAX TEMPERATURES AND EXPECT HIGHS
TO RANGE FROM THE UPPER 30S/LOW 40S IN OUR NORTHWEST ZONES TO THE
UPPER 40S IN THE DELMARVA. THE SURFACE HIGH PRESSURE AND MID-LEVEL
RIDGE ARE THEN EXPECTED TO PASS OFFSHORE INTO MONDAY NIGHT AS A LOW
PRESSURE SYSTEM ACROSS THE PLAINS ADVANCES EAST INTO THE GREAT
LAKES. THE ASSOCIATED WARM FRONT IS EXPECTED TO APPROACH OUR REGION
FROM THE SOUTHWEST INTO EARLY TUESDAY AND LIFT NORTH OF THE AREA
THROUGH THE DAY. WHILE THIS IS EXPECTED TO BE MAINLY A RAIN EVENT
FOR THE FORECAST AREA TUESDAY INTO TUESDAY NIGHT, THERE MAY BE
ENOUGH LINGERING COLD AIR AT THE SURFACE IN THE SOUTHERN POCONOS AND
FAR NORTHWEST NJ FOR A BRIEF PERIOD OF PATCHY FREEZING RAIN/DRIZZLE
AT THE ONSET OF PRECIPITATION EARLY TUESDAY AS SOME WARMING OCCURS
ALOFT. ON THE POSITIVE SIDE, QPF AMOUNTS LOOK LIGHT FOR THIS PERIOD,
AND BY MID TO LATE MORNING, SURFACE TEMPERATURES SHOULD BE ABOVE
FREEZING FOR THESE AREAS. WE FOCUS HIGHER CHANCE POPS FOR RAIN
ACROSS MOST OF THE FORECAST AREA THEN INTO TUESDAY AFTERNOON, BEFORE
GRADUALLY TRIMMING BACK POPS INTO TUESDAY EVENING AND NIGHT WHEN THE
ASSOCIATED COLD FRONT WITH THIS SYSTEM IS EXPECTED TO APPROACH THE
REGION. MOST OF THE FORCING AND LIFT LOOKS TO PASS BY TO OUR NORTH,
AND WE ONLY EXPECT LIMITED PRECIP INTO TUESDAY NIGHT/OVERNIGHT.
TEMPERATURES FOR THE MOST PART ARE EXPECTED TO REMAIN ABOVE FREEZING
THROUGH TUESDAY NIGHT, BUT THERE COULD BE SOME MIXING OF SNOW WITH
RAIN BEFORE THE PRECIP TAPERS OFF, MAINLY FOR NORTHWEST AREAS FROM
PORTIONS OF THE LEHIGH VALLEY AND NORTHWEST NJ INTO THE POCONOS.

WHILE SOME IMPROVEMENT IS EXPECTED FOR OUR REGION INTO WEDNESDAY AS
A BROAD AREA OF SURFACE HIGH PRESSURE STRETCHING ACROSS THE PLAINS
AND MIDWEST SLOWLY STARTS TO BUILD EASTWARD, LINGERING SURFACE AND
UPPER LOW PRESSURE LOOK TO HANG AROUND TO OUR NORTHEAST. WHILE WE
ARE ANTICIPATING A MAINLY DRY WEDNESDAY WITH MORE CLOUDS THAN SUN,
SOME SCATTERED FLURRIES OR SNOW SHWRS CANNOT BE RULED OUT FOR THE
HIGHER TERRAIN OF OUR NORTHWEST ZONES, ESPECIALLY IN THE ANTICIPATED
WEST-NORTHWEST FLOW. THROUGH THE END OF THE WORK WEEK THEN, FAIRLY
QUIET WEATHER IS EXPECTED AS THE PREVIOUSLY MENTIONED BROAD HIGH
PRESSURE GRADUALLY PROGRESSES EASTWARD. MIXED SUN AND CLOUDS ARE
EXPECTED FOR THE MOST PART THROUGH THURSDAY AND FRIDAY WITH NEAR TO
BELOW AVERAGE TEMPERATURES.

THE NEXT SYSTEM ON THE HORIZON TO WATCH AT THE VERY END OF THE LONG
TERM PERIOD WILL BE A DEVELOPING LOW PRESSURE SYSTEM AROUND THE GULF
COAST STATES LATE FRIDAY INTO SATURDAY. THERE IS MUCH UNCERTAINTY AT
THIS TIME WITH THIS SYSTEM BETWEEN THE GFS, ECMWF, AND OTHERS
REGARDING THE STRENGTH OF AN INCOMING SHORTWAVE AND ITS INTERACTION
WITH THE DEVELOPING SURFACE LOW ACROSS THE DEEP SOUTH. IN ADDITION,
THE TRACK OF THIS LOW PRESSURE INTO SATURDAY AND BEYOND IS HIGHLY
UNCERTAIN. THE GFS IS THE WARMER SOLUTION WITH MORE OF AN INLAND
TRACK UP THROUGH THE TENNESSEE VALLEY AND EVENTUALLY THE SOUTHERN
MID ATLANTIC REGION, WHILE THE ECMWF IS COLDER, KEEPING THE LOW
PRESSURE FARTHER SOUTH AND THEN EVENTUALLY EMERGING OFF THE MID
ATLANTIC COAST. FOR NOW, WE HAVE POPS NO HIGHER THAN CHANCE FOR
SATURDAY WITH THIS MUCH UNCERTAINTY IN THE TIMING AND TRACK OF THIS
LOW PRESSURE, AS WELL AS QPF AMTS AND PRECIP TYPE.

&&

.AVIATION /16Z SUNDAY THROUGH THURSDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.

THE PESKY STRATOCU WILL BE WITH US ONE MORE DAY AND IT APPEARS THAT
WE WILL TEETER BETWEEN VFR AND MVFR.  IF WE GET BREAKS THEN VFR, AND
IF NOT IT WILL  BE MVFR AS THESE CLOUDS SEEM TO WANT TO HOLD AROUND
2500 FT.  ITS PSBL THAT BY LATER TODAY CONDS WILL BREAK OUT A BIT AS
HIGH PRESSURE GETS CLOSER.  CONDS SHUD BECOME VFR TONIGHT AS THE
HIGH IS VIRTUALLY OVERHEAD.  NOT SURE ON THE TIMING OF THE RETURN TO
VFR THIS AFTN.  CUD END UP BEING LATER THAN FCST, AS THESE CLOUDS
SEEM TO NOT WANT TO GIVE UP.

WIND WILL REMAIN OUT OF THE NW, GENLY AROUND 10 KT.

OUTLOOK...
MONDAY...VFR CONDITIONS WITH LIGHT NORTHWEST WINDS.

TUESDAY...VFR CONDITIONS TO START THE DAY, BUT MVFR CONDITIONS MAY
DEVELOP AS PRECIP DEVELOPS ACROSS THE REGION. MAINLY RAIN SHWRS ARE
EXPECTED, BUT THE PRECIP COULD BRIEFLY BEGIN AS RAIN/FREEZING RAIN
FOR OUR NORTHWEST SITES, INCLUDING KABE AND KRDG.

WEDNESDAY...POSSIBLE MVFR CONDITIONS TO START, WITH IMPROVEMENT BACK
TO VFR EXPECTED BY MIDDAY TO AFTN.

THURSDAY...VFR CONDITIONS ARE EXPECTED.

&&

.MARINE...
WE HAVE DECIDED TO CANCEL THE SCA FLAG AS OF THE LATE MORNING.
WINDS HAVE NOT INCREASED SO FAR TODAY...AND IT APPEARS THAT THE
GUIDANCE MAY BE TOO HIGH FOR LATER TODAY. I WOULD STILL HOLD ON TO
THE POSSIBILITY FOR A FEW GUSTS AROUND 20 KNOTS EARLY THIS
AFTERNOON.

OUTLOOK...
MONDAY AND TUESDAY...SUB-ADVISORY CONDITIONS ARE EXPECTED.

WEDNESDAY AND THURSDAY...WHILE SEAS ARE EXPECTED TO REMAIN BELOW SCA
LEVELS, NORTHWEST WIND GUSTS COULD REACH THE SCA THRESHOLD OF 25
KNOTS AT TIMES.

&&

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

&&

$$
SYNOPSIS...KLINE
NEAR TERM...O`HARA
SHORT TERM...NIERENBERG
LONG TERM...KLINE
AVIATION...KLINE/NIERENBERG
MARINE...KLINE/O`HARA







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