Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

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000
FXUS61 KPHI 101959
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
259 PM EST WED FEB 10 2016

.SYNOPSIS...
LOW PRESSURE OVER THE SAINT LAWRENCE VALLEY WILL MOVE INTO THE BAY
OF FUNDY THURSDAY, WHILE HIGH PRESSURE OVER THE UPPER MISSISSIPPI
VALLEY MOVES INTO THE MIDDLE ATLANTIC ON FRIDAY. A STRONG ARCTIC
COLD FRONT WILL MOVE THROUGH OUR REGION ON SATURDAY, SWEEPING LOW
PRESSURE OVER THE OUTER BANKS OF NORTH CAROLINA WELL OUT TO SEA.
HIGH PRESSURE WILL MOVE INTO OUR AREA FROM THE OHIO VALLEY ON
SUNDAY, AND MOVE OFF THE MID ATLANTIC COAST ON MONDAY. TWO STORM
SYSTEMS ARE EXPECTED TO JOIN FORCES OVER THE MIDDLE ATLANTIC,
AND MOVE UP THE EAST COAST ON TUESDAY AND WEDNESDAY.

&&

.NEAR TERM /THROUGH TONIGHT/...
TONIGHT...NEGATIVE TILT SHORT WAVE PROBABLY PRODUCES FLURRIES AND
SCATTERED DUSTING SNOW SHOWERS IN THE 02Z-10Z TIME FRAME, AND
THOUGHT MOSTLY I-78 CORRIDOR NORTHWARD (POSSIBLY A CONNECTION TO
LAKE ERIE SNOW SHOWER PLUME) BUT THERE MAY BE A BATCH THAT CROSSES
THE DELMARVA, ENHANCED BY THE CHESAPEAKE BAY. ANY SNOW AMTS UNDER
1 INCH. WILL POST AN OVERNIGHT STS GRAPHIC WHICH SAYS LESS THAN 1
INCH BUT IN REALITY, EXPECTING LESS THAN 1/2 INCH WITHIN SCATTERED
BANDS, MOSTLY PA. TEMPERATURES NEAR NORMAL. GUSTY WEST WINDS TO 25
MPH PROBABLY DIMINISH FOR A WHILE TONIGHT. IT MAY TEMPO CLEAR AFTER
SUNSET THIS EVENING AND THAN PROBABLY PARTIALLY CLEAR TOWARD DAWN
AFTER THE SHORT WAVE PASSAGE.

&&

.SHORT TERM /THURSDAY/...
PARTLY SUNNY AND BRISK. SCATTERED BRIEF SNOW SHOWERS OR FLURRIES,
MAINLY I-78 NWWD WHERE VERY UNSTABLE 925-700MB LAPSE RATES AND
SEMBLANCE OF A TROUGH. BTV SNOW SQUALL PARAMETER PREDICTION TOOL
HAS SUPPORTIVE INDICATION. GUSTY WEST NORTHWEST WINDS TO 35 MPH
11 AM TO 3 PM. MAX TEMPS ABOUT 10F BELOW NORMAL.

&&

.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
THE EXTENDED WILL LIKELY FEATURE BOTH THE PROSPECTS FOR THE COLDEST
AIR OF THE SEASON CENTERED ON SUNDAY MORNING AND A STRENGTHENING LOW
PRESSURE SYSTEM TRACKING UP THE EAST COAST EARLY NEXT WEEK.


THURSDAY AND THURSDAY NIGHT: HIGH PRESSURE WILL GRADUALLY BUILD
EASTWARD FROM THE OHIO VALLEY TOWARD THE REGION. OUR REGION WILL
CONTINUE TO SEE STRONG CAA WITH A WEST-NORTHWEST WIND OFF THE
EASTERN GREAT LAKES. BUFKIT ANALYSIS SHOWS THAT STRONG WIND GUSTS
MAY REACH 30 MPH AT TIMES. ALSO LOW LEVEL LAPSE RATES WILL ALSO
STEEPEN DURING THE DAY WHICH COULD BE ENOUGH TO DEVELOP SOME
SCATTERED SNOW SHOWERS AND FLURRIES DURING THE DAY WITH THE
HIGHEST COVERAGE AIDED BY ELEVATION ACROSS EASTERN PA AND NW NJ.
WITH THE STRONG CAA PUSH WILL TREND TEMPERATURES A BIT LOWER THAN
MET/MAV AND ENSEMBLE GUIDANCE.

THE PRESSURE GRADIENT WILL RELAX THURSDAY NIGHT ALLOWING FOR
WINDS TO DECREASE AS A HIGH PRESSURE SYSTEM MOVES INTO THE REGION.
CONDITIONS LOOK MORE FAVORABLE FOR RADIATIONAL COOLING COMPARED TO
TONIGHT.


FRIDAY AND SATURDAY: HIGH PRESSURE WILL MOVE THROUGH THE REGION ON
FRIDAY. THIS HIGH PRESSURE SYSTEM WILL GIVE WAY TO ANOTHER ARCTIC
COLD FRONT. THE FRONT MOVES THROUGH THE REGION FRIDAY NIGHT AND
SATURDAY. TRENDS WITH BOTH THE OPERATIONAL AND ENSEMBLE GUIDANCE
FORM A COASTAL LOW PRESSURE SYSTEM SOUTHEAST OF US AND OFFSHORE,
SO THE POSSIBILITY OF A COASTAL LOW NEAR US IN THIS PERIOD HAS
GREATLY DECREASED. IT WILL BE A VERY COLD AND WINDY PERIOD WITH
ANOTHER ROUND OF NW FLOW SNOW SHOWERS AND FLURRIES BEHIND THE
FRONT WITH THE HIGHEST COVERAGE IN THE HIGH TERRAIN AREAS IN
EASTERN PA AND NW NJ, SIMILAR TO THE MIDDLE OF THIS WEEK. BUFKIT
ANALYSIS SHOWS THE POTENTIAL FOR MIXING AGAIN SATURDAY SIMILAR TO
THURSDAY SO WIND GUSTS COULD BE QUITE STRONG, OVER 30 MPH AGAIN.

SATURDAY NIGHT THROUGH SUNDAY NIGHT: ANOTHER POTENT AREA OF ARCTIC
HIGH PRESSURE WILL BUILD INTO THE REGION WITH THE COLDEST SHOT OF
AIR OF THE SEASON SO FAR. 850 MB LOOK TO DIVE BELOW -25C ACROSS MOST
OF REGION AS CURRENTLY MODELED. AS IN OTHER PERIODS WILL CONTINUE TO
NUDGE TEMPERATURES A COUPLE OF DEGREES COOLER THAN MOST ENSEMBLE
GUIDANCE. NORTHWEST WINDS ALTHOUGH NOT AS STRONG AS SATURDAY WILL
LIKELY TO BELOW ZERO WIND CHILLS, PUSHING ADVISORY CRITERIA IN
SPOTS FROM -10 IN THE DELMARVA TO LOWER THAN -20 IN THE POCONOS.

PRESIDENTS DAY THROUGH TUESDAY: HIGH PRESSURE WILL GRADUALLY MOVE
EAST OF THE REGION AND WILL GIVE WAY TO A STORM SYSTEM THAT IS
CURRENTLY MODELED TO FORM ACROSS THE SOUTHERN UNITED STATES MONDAY
AND TRACK UP THE EAST COAST TUESDAY. TWO CAMPS ARE CURRENTLY
PRESENT WITH THE TRACK OF THE STORM SYSTEM. THE MAIN DIFFERENCES
BETWEEN THE TWO SOLUTIONS ARE THE SPEED OF VARIOUS SHORTWAVES
WHICH ULTIMATELY DEVELOP THE STORM ACROSS THE SOUTHERN UNITED
STATES AND THE DEGREE OF MID-LEVEL RIDGING MODELS DEVELOP AHEAD OF
IT. THE UKMET AND ECMWF ARE SLOWER WITH OVERALL TIMING ALLOWING
FOR MID-LEVEL RIDGING TO FORM OVER THE REGION AND IN NEW ENGLAND.
THIS ALLOWS FOR AS WARMER AND FURTHER WEST TRACK WHICH WOULD
RESULT IN MAINLY A RAIN EVENT. THE FASTER GFS AND CMC SOLUTIONS
SHIFT THE DEVELOPING SYSTEM FURTHER EAST AND ARE FASTER, TRACKING
IT UP THE EAST COAST WHICH WOULD BE A SNOWIER OUTCOME. FOR NOW
WILL TAKE A MIDDLE OF THE ROAD APPROACH, THIS BRINGS SNOW IN
MONDAY WHICH GRADUALLY MIXES AND CHANGES TO RAIN BY TUESDAY.
ENSEMBLE DATA IS CURRENTLY LEANING TOWARD THE WARMER WESTWARD
TRACK. HOWEVER, GIVEN THIS IS SEVERAL DAYS A LOT OF ENSEMBLE
SPREAD IS STILL PRESENT AND THE VARIOUS FEATURES INVOLVED WILL NOT
EVEN SAMPLED BY OBSERVATIONAL DATA FOR SEVERAL MORE DAYS.

&&

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

REMAINDER OF TODAY...VFR GENERALLY BKN CIGS AOA 4000 FT. WEST
WIND GUST 20-25 KT.

TONIGHT...VFR WITH CIGS REDEVELOPING MAINLY AOA 4000 FT. THOSE
CIGS MAY BRIEFLY LOWER TO MVFR CONDS IN BANDS OF SNOW SHOWERS
SOMETIME BETWEEN 03Z AND 09Z, ESPECIALLY VCNTY KABE/KTTN/KRDG.
WEST WIND GUSTS TO 20 KT. CONFIDENCE: AVERAGE.

THURSDAY...VFR SCT-BKN AOA 4000 FT. WEST-NORTHWEST WIND GUSTS
AROUND 30 KT IN THE AFTERNOON, POSSIBLY ISOLATED 35 KT. SOME BRIEF
MVFR RESTRICTIONS IN ISOLATED SNOW SHOWERS AND FLURRIES POSSIBLE
VCNTY KRDG/KABE. CONFIDENCE: AVERAGE.

OUTLOOK...

THURSDAY NIGHT AND FRIDAY: VFR. NORTHWEST WINDS UNDER 15 KNOTS
SHIFTING TO SOUTHWEST ON FRIDAY

FRIDAY NIGHT AND SATURDAY: MAINLY VFR, POSSIBLE MVFR RESTRICTIONS
IN SCATTERED SNOW SHOWERS. NORTHWEST WINDS INCREASING SATURDAY
FROM 15-25 KNOTS WITH HIGHER GUSTS ON SATURDAY.


SUNDAY...VFR WITH DIMINISHING NORTHWEST WINDS.

&&

.MARINE...
SST`S ARE AROUND 5 TO 8F WARMER THAN NORMAL FOR FEBRUARY AND THESE
WATER TEMPERATURES WARMED ABOUT 5 DEGREES FROM THE MID JANUARY WATER
TEMPERATURE TUMBLE. THE REASONING FOR THE WARMING, EVEN IN DE BAY
IS NOT WELL UNDERSTOOD BY MYSELF BUT IT HAS OCCURRED AND I THINK
BECOMES A MORE IMPORTANT PLAYER IN AIDING MOMENTUM TRANSFER THROUGH
THESE COLD AIR ADVECTION EPISODES BY STEEPENING THE BOUNDARY LAYER
LAPSE RATE.

GLW CONTD. FUNNELING AND EARLIER START TO THE DEEPENING BOUNDARY
LAYER MIXING FOR DE BAY SHOULD PERMIT A FEW GUSTS TO 35 KT VCNTY
SJS, BWINE...LWS SOMETIME BETWEEN 1 AM AND 4 AM THURSDAY.
CONFIDENCE ON THE STARTING TIME OF GALE GUSTS THERE IS AVERAGE.

THEREAFTER...WNW GALE GUSTS SPREAD TO THE ATLANTIC WATERS OF NJ
AND DE DURING THE MORNING, BECOMING MOST PERSISTENT THURSDAY
AFTN/EVE WHEN A FEW GUSTS TO 40 KT ARE EXPECTED. HIGH CONFIDENCE.

WE HAVE NO WIND DATA AT 44009 SO TO VERIFY, WE HAVE 44065 AND WE
USE MULTIPLE COASTAL WIND OBSERVATIONS ADJACENT THE WATER INCLUDING
NOS/USGS/WEATHERFLOW MESONET PLATFORMS.

OUTLOOK...

SCA NORTHWEST WINDS EARLY FRIDAY. AFTER A LULL WITH SEAS AND
WINDS FOR A GOOD PART OF FRIDAY AND MAYBE INTO EARLY SATURDAY AN
ARCTIC COLD FRONT WILL LEAD TO RAMP UP ON SATURDAY. ANOTHER ROUND
OF NORTHWEST GALE FORCE GUSTS ARE LIKELY SATURDAY AFTERNOON AND
EVENING WITH SEAS NEAR AND OVER FIVE FEET. STRONG NORTHWEST WIND
GUSTS BELOW GALE FORCE WILL LINGER INTO SUNDAY. IN ADDITION TO THE
THREAT FOR GALES SEVERAL ROUNDS OF FREEZING SPRAY CONDITIONS ARE
POSSIBLE AS WELL WITH THE FIRST ROUND WEDNESDAY NIGHT INTO
THURSDAY AND THE POTENTIAL FOR MODERATE TO HEAVY FREEZING SPRAY
THIS WEEKEND.

&&

.CLIMATE...
NEAR RECORD COLD IS EXPECTED FOR PORTIONS OF OUR AREA SUNDAY
MORNING AND BY FAR THE COLDEST AIR OF THE SEASON SO FAR.

ANTICIPATING TEMPS THROUGHOUT OUR FORECAST AREA WITHIN SEVERAL
DEGREES OF ZERO (WIND IS THE EQUALIZER) ANYTIME FROM MIDNIGHT
THROUGH 8 AM SUNDAY EXCEPT COLDER KMPO (NEAR -12F). THIS HAS BEEN
ADVERTISED BY THE GFS/ECMWF 2M TEMPS CYCLICALLY SINCE AT LEAST THE
00Z/7 OPERATIONAL CYCLES. THEREFORE, BEST CHANCE FOR RECORD EQUALING
OR EXCEEDING FOR VALENTINES DAY THE 14TH WOULD BE KABE, KTTN, KPHL
AND KMPO.

SNOWCOVER MAY HELP A BIT I-95 NORTHWESTWARD...AND WE`LL SEE WHERE
WE ARE WITH SNOWCOVER BY THURSDAY EVENING. NEW DUSTINGS APPEAR ON
THE WAY THE NEXT 30 HOURS.


2015-16 SO FAR RER 14TH

ABE 8......... -1 1979

ACY 10........ -6 1979

PHL 12........ +2 1979

ILG 12........ -4 1979

RDG 10........ -4-1983

TTN 9.........  0 1916

GED 13........  -7 1979

MPO -1........ -12 1970

SO, THIS WILL BE WIND DRIVEN COLD WITH MANY AREAS EXPERIENCING
WIND CHILL VALUES OF 15 TO 25 BELOW ZERO...POSSIBLY 30 BELOW IN
THE HILLS AND MOUNTAINS OF NORTHWEST NEW JERSEY AND NORTHEAST
PENNSYLVANIA.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EST THURSDAY FOR ANZ450>455.
     GALE WARNING FROM 6 AM THURSDAY TO 1 AM EST FRIDAY FOR
     ANZ450>455.
     SMALL CRAFT ADVISORY UNTIL 1 AM EST THURSDAY FOR ANZ430-431.
     GALE WARNING FROM 1 AM TO 11 PM EST THURSDAY FOR ANZ430-431.

&&

$$
SYNOPSIS...GAINES/FRANCK 257
NEAR TERM...DRAG 257
SHORT TERM...DRAG 257
LONG TERM...GAINES
AVIATION...DRAG/GAINES 257
MARINE...DRAG/GAINES 257
TIDES/COASTAL FLOODING...257
CLIMATE...257


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