Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

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000
FXUS61 KPHI 172003
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
303 PM EST WED DEC 17 2014

.SYNOPSIS...
LOW PRESSURE FROM THE GULF OF MAINE TO QUEBEC WILL MERGE AND INTENSIFY
OVER THE MARITIMES BY THURSDAY. HIGH PRESSURE ASSERTS CONTROL HERE
ON FRIDAY. LOW PRESSURE IN GEORGIA SATURDAY IS FORECAST TO INTENSIFY
AS IT MOVES NORTHEASTWARD OFF THE SOUTHERN MID ATLANTIC COAST
SUNDAY INTO MONDAY. ANOTHER STORM SYSTEM MAY IMPACT THE REGION
JUST BEFORE CHRISTMAS DAY.

&&

.NEAR TERM /THROUGH TONIGHT/...
REMAINDER OF THIS AFTERNOON...CONSIDERABLE CLOUDINESS ACROSS MOST
OF THE REGION EXCEPT SOUTHERN PORTION OF OUR DELMARVA RESPONSIBILITY
THIS AFTERNOON. SKIES BEGIN CLEARING SOON. SPRINKLES IN THE POCONOS
WESTWARD SHOULD SOON MIX WITH FLURRIES HIGH TERRAIN THERE. GUSTS NEAR
25 MPH SOON DIMINISH SOMEWHAT TOWARD SUNSET.

TONIGHT...THE SOUTHEASTERN TWO THIRDS OF THE REGION SHOULD SEE CLEARING
SKIES. THE NW PORTION COULD SEE SOME FLURRIES...I-80 NORTH IN RESPONSE
TO A 100M 12 HR 500MB HFC (STRONG VORT MAX CURRENTLY LOWER LAKES)
SWEEPING SEWD THRU THE POCONOS AROUND 06Z/18. MODEL GUIDANCE IS
NOT SHOWING MUCH SENSIBLE WX RESPONSE. W-NW OCCASIONALLY GUST 20
MPH.

&&

.SHORT TERM /THURSDAY/...
THURSDAY...WE ARE IN SERVICE BACKUP AND STERLING WILL BE WRITING
THE FORECASTS STARTING AT ABOUT 8 AM.

IT WILL BE A BIT COOLER (STILL ABOVE NORMAL)...ABOUT 8-9F PER MODELED
925MB ABOUT 5C COOLER...WITH GUSTY NW WINDS TO 25 MPH.

CONSIDERABLE CLOUDINESS POCONOS WITH MAYBE A FEW FLURRIES? OTHERWISE
A MOSTLY SUNNY START IS EXPECTED BECOMING PARTLY SUNNY OR MOSTLY
CLOUDY FOR A TIME MIDDAY THEN CLEARING LATE IN THE DAY.

&&

.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
NOT MUCH CHANGE TO THE LONGTERM FROM THE PREVIOUS 24 HOURS. LOOKS
LIKE A TRANQUIL PATTERN FROM THURSDAY INTO EARLY SATURDAY BEFORE
DEEPER MORE ESTABLISHED TROUGHING COMMENCES OVER THE MID-WEST. AMPLE
NORTHERN AND SOUTHERN STREAM ENERGY WILL BE PASSING THROUGH FROM
SUNDAY ONWARD THOUGH THINGS, FOR THE MOST PART, APPEAR TO BE
DISCONNECTED WITH CONTINUED SPLIT FLOW...TUESDAY INTO WEDNESDAY
THAT COULD CHANGE.

THURSDAY NIGHT - FRIDAY...DRYING TREND CONTINUES WITH ZONAL-ISH
FLOW ALOFT FORMING BY FRIDAY AND NOT MUCH MOISTURE TO WORK WITH.
GUSTY NORTHWEST WINDS.

SATURDAY - SUNDAY...ONE LAST DAY, OR AT LEAST HALF DAY, OF
TRANQUILITY ON SATURDAY BEFORE EAST COAST STORM NEARS FROM THE
SOUTH-SOUTHWEST. DEPENDING ON THE QUICKNESS AND POSITION OF THE
NORTHERN STREAM ENERGY, HELPING TO DEVELOP GULF COAST SURFACE
INFLECTION, DICTATES HOW FAST PRECIPITATION OVERSPREADS FROM THE
SOUTH LATER ON SATURDAY. WE CONTINUE TO SEE A WEAKENING TREND IN THE
OPERATIONAL GUIDANCE PACKAGES FOR THIS SYSTEM. MOST OF THE QPF
EXPECTED TO FALL DURING THIS TIMEFRAME IS ASSOCIATED WITH THE
NORTHERN STREAM ENERGY, AND THAT TOO LOOKS LIKE IT IS BECOMING MORE
WASHED OUT. AN INVERTED TROUGH MAY THROW BACK SOME MOISTURE ACROSS
THE REGION TOO. AS FOR PTYPES, THE INTERIOR ZONES HAVE THE BEST
CHANCES OF SEEING SNOW WHILE I-95 EASTWARD LOOKS MOSTLY LIKE LIQUID
ON SATURDAY EVENING. A MIXTURE OF RAIN/SNOW MAY OCCUR DURING THE EARLY
MORNING HOURS ON SUNDAY AS THE NORTHERN TROUGH GOES SLIGHTLY
NEGATIVE. AREAS FARTHER NORTH AND WEST OF PHILLY COULD SEE A LIGHT
ACCUMULATION OF SNOW EARLY SUNDAY MORNING.

MONDAY - TUESDAY...COULD STILL BE DEALING WITH THE LINGERING EFFECTS
OF THE SYSTEM PROGGED TO MOVE BY ON SUNDAY, DEPENDING ON HOW FAST IT
PULLS AWAY FROM THE REGION. STARTING TO SEE MORE NORTHERN STREAM
ENERGY FUNNEL INTO THE PLAINS STATES LATER ON MONDAY AND TUESDAY.
THIS WILL FORM THE NEXT SYSTEM THAT LOOKS TO IMPACT OUR REGION RIGHT
BEFORE CHRISTMAS. THERE IS STILL PLENTY OF UNCERTAINTY WITH
THIS SYSTEM AS WELL AND WE NEED TO SEE HOW THE PRIOR SYSTEM, ON
SUNDAY/MONDAY, DISRUPTS THE MID-LEVEL FLOW, IF AT ALL, BEFORE WE
HAVE ANY INKLING AS TO HOW TUESDAYS SYSTEM WILL PROGRESS.

&&

.AVIATION /20Z WEDNESDAY THROUGH MONDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.

REMAINDER OF THIS AFTERNOON...CIGS AOA 3500 FEET. GUSTY W-NW WIND
NEAR 25 KT SUBSIDES SLIGHTLY TOWARD SUNSET. BRIEF IFR CONDS
POSSIBLE POCONOS IN SCT SHOWERS OF RAIN CHANGING TO SNOW .
CONFIDENCE: ABOVE AVERAGE.

TONIGHT...VFR SCT CLOUDS AOA 3500 FT. MVFR CONDS POSSIBLE IN THE
POCONOS IN A SNOW SHOWER. NW WINDS GUST 20 KT. CONFIDENCE: ABOVE
AVERAGE.

THURSDAY...VFR CLEAR OR SCT CLOUDS AOA 3500 FT BECOMING BRIEFLY
BKN CIGS MIDDAY EARLY AFTERNOON THEN CLEARING LATE. NORTHWEST
WINDS 10-15KT WITH GUSTS 20-25KT. CONFIDENCE: ABOVE AVERAGE.

OUTLOOK...

FRIDAY - SATURDAY...VFR. COULD SEE RAIN/SNOW SHOWERS SATURDAY AFTERNOON.

SUNDAY...SUB-VFR EXPECTED WITH SCATTERED RAIN/SNOW SHOWERS.

&&

.MARINE...
SCA POSTED. SCA VERIFICATION OCCURRING MOST OF THE COAST. WINDS
SHOULD SUBSIDE SOMEWHAT THIS EVENING THEN MAY PULSE UP DURING THE
NIGHT WITH ISOLATED GUSTS 30-33 KT POSSIBLE BY MORNING. WINDS ON
THURSDAY SHOULD BE STRONGEST DURING THE MORNING THEN MAY SUBSIDE A
BIT DURING MID AND LATE AFTERNOON.

THE SCA ON DE BAY MAY EITHER BE EXTENDED OR PERMITTED TO DROP AT 6
PM THIS EVENING WITH A RE-ISSUANCE OF AN SCA LIKELY TO BE NEEDED
FOR THURSDAY MORNING.

BUOY 44009 FULL SERVICE RESTORATION PROBABLY DELAYED TIL FEBRUARY
2015.

OUTLOOK...
THURSDAY...SCA CONDITIONS SHOULD CONTINUE THROUGH MOST OF THE DAY
BEFORE WINDS BEGIN TO DECREASE BY LATE AFTERNOON. CONFIDENCE: ABOVE
AVERAGE.

FRIDAY...MOSTLY SUB-ADVISORY CONDITIONS ARE EXPECTED. SOME NORTHWEST
WIND GUSTS COULD STILL BE IN THE 20 PLUS KNOT RANGE, THOUGH.
CONFIDENCE: ABOVE AVERAGE.

SATURDAY - SUNDAY...SUB-SCA EXPECTED FOR THE MOST PART. SEAS REMAIN
AROUND 3 TO 4 FEET.  CONFIDENCE: AVERAGE TO SLIGHTLY BELOW AVERAGE.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 5 PM EST THURSDAY FOR ANZ450>455.
     SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR ANZ430-
     431.

&&

$$
SYNOPSIS...DRAG/HEAVENER  303
NEAR TERM...DRAG 303
SHORT TERM...DRAG 303
LONG TERM...HEAVENER
AVIATION...DRAG/HEAVENER 303
MARINE...DRAG/HEAVENER 303





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