Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

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000
FXUS61 KPHI 171533
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1033 AM EST WED DEC 17 2014

.SYNOPSIS...
LOW PRESSURE FROM NEAR CAPE COD TO QUEBEC WILL MERGE AND INTENSIFY
OVER THE MARITIMES BY THURSDAY. HIGH PRESSURE ASSERTS CONTROL HERE
ON FRIDAY. LOW PRESSURE IN GEORGIA SATURDAY MORNING 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 /UNTIL 7 PM THIS EVENING/...
DIURNAL HEATING WITH LEFTOVER BOUNDARY LAYER MOISTURE WILL GENERATE
CONSIDERABLE CLOUDINESS ACROSS THE REGION THIS AFTERNOON. AS THE
BOUNDARY LAYER DEEPENS...GUSTINESS WILL INCREASE WITH AFTERNOON
GUSTS TO 25 MPH. THE POCONOS AND NW NJ WHICH WILL BE CLOSER TO THE
TRACK OF THE CENTER OF THE UPPER LEVEL LOW THROUGH THE DAY TODAY
WITH POTENTIAL FOR SPRINKLES OR SHOWERS DURING MIDDAY OR THE
AFTERNOON.

&&

.SHORT TERM /7 PM THIS EVENING THROUGH 6 PM THURSDAY/...
TONIGHT...THE SOUTHEASTERN TWO THIRDS OF THE REGION SHOULD SEE
CLEARING SKIES. THE NW PORTION COULD SEE SOME FLURRIES...I80 NORTH
IN RESPONSE TO AN INTENSIFYING 120M 12 HR 500MB HFC SWEEPING SEWD
THRU THE POCONOS (12Z/17 KERIE 50-70M HFC). MODEL GUIDANCE IS NOT
SHOWING MUCH SENSIBLE WX RESPONSE. ALL WEATHER CHANGED TO FLURRIES
IN THE POCONOS WHERE IT SHOULD BE COLD ENOUGH ALOFT FOR CRYSTAL
ICE NUCLEI.

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

WILL BE A BIT COOLER...ABOUT 5 TO 7 DEGREES PER MODELED 925MB
ABOUT 5C COOLER...WITH GUSTY NW WINDS TO 25 MPH...MAYBE A FEW
FLURRIES IN THE POCONOS ...OTHERWISE MIXED CLOUDS AND SUN.

&&

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

THROUGH THIS AFTERNOON...PATCHY CIGS AOA 3500 FEET BECOMING MORE
WIDESPREAD WITH GUSTY NW WINDS TO NEAR 25 KT BY NOON. BRIEF IFR CONDS
POSSIBLE POCONOS IN STRATUS AND/OR A SHOWER. CONFIDENCE: ABOVE
AVERAGE.

TONIGHT...VFR SCT CLOUDS AOA 3000 FT. MVFR CONDS POSSIBLE IN THE
POCONOS IN A SNOW SHOWER. NW WINDS GUST 20 KT. CONFIDENCE: ABOVE
AVERAGE.

THURSDAY...VFR SCT-BKN CLOUDS AOA 3500 FT. 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. WINDS SHOULD INCREASE TO REACH NEAR 25 KT GUSTS MIDDAY
AND SCA WINDS CONTINUE INTERMITTENTLY THROUGH THURSDAY. MAY ADD
LOWER DE BAY TO THE SCA FOR TONIGHT AND THURSDAY IN FUTURE AFTERNOON
FCST ISSUANCE.

WAVES NEAR OR ABOVE 5 FT ARE POSSIBLE ONCE THE WINDS INCREASE,
ESPECIALLY ON THE ATLANTIC COASTAL WATERS.

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 1033
NEAR TERM...DRAG 1033
SHORT TERM...DRAG
LONG TERM...HEAVENER
AVIATION...DRAG/HEAVENER 1033
MARINE...DRAG/HEAVENER 1033






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