Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

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802
FXUS61 KPHI 101541
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1041 AM EST WED FEB 10 2016

.SYNOPSIS...
LOW PRESSURE ACROSS NEW ENGLAND WILL CONTINUE TO MOVE NORTHEAST AWAY
FROM THE REGION TODAY. HIGH PRESSURE WILL BUILD EASTWARD INTO THE
REGION THURSDAY AND THEN MOVE THROUGH ON FRIDAY BEFORE GIVING WAY TO
A ARCTIC COLD FRONTAL BOUNDARY BY THE END OF THE WEEK. ON SUNDAY,
ANOTHER AREA OF HIGH PRESSURE WILL BUILD SOUTHWARD INTO THE REGION
AS LOW PRESSURE FORMS ACROSS THE SOUTHERN UNITED STATES BY MONDAY.
THIS AREA OF LOW PRESSURE WILL THEN TRACK UP THE EAST COAST ON
TUESDAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
1025 AM: CATCHING UP. DECIDED TO ISSUE A STORM TOTAL SNOW AT 815
AM AND WITHDRAW SNOW PROBS DUE TO ON-GOING BRIEFLY SIGNIFICANT
MORNING SNOW SHOWER BAND. SOON WILL REINTRODUCE SNOW PROBS AND
WITHDRAW STORM TOTAL SNOW.

NO MAJOR CHANGES TO THE REMAINDER OF THE FORECAST THOUGH DID
INCREASE WIND GUSTS ABOUT 5 KT THIS AFTERNOON.

UPPER LEVEL SHORT WAVE TROUGH LIFTS THROUGH THE REGION EARLY IN
THE DAY. AS A RESULT, WE SHOULD SEE LINGERING SNOW SHOWERS MOVE
OUT OF THE REGION BY MID DAY.

IN THE LOW LEVELS, A GUSTY WESTERLY FLOW DEVELOPS, RESULTING IN
LOW LEVEL COLD AIR ADVECTION. AS SUCH, EXPECT HIGHS WILL ONLY BE
IN THE 30S FOR MOST OF THE REGION, WHILE THE POCONOS MAY NOT GET
OUT OF THE 20S.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM THURSDAY/...
A SECOND, LESS DEFINED, MID AND UPPER LEVEL SHORT WAVE TROUGH WILL
APPROACH FROM THE WEST OVERNIGHT. CONTINUED THE TREND OF A SMALL
CHANCE OF SNOW SHOWERS. HOWEVER, I AM NOT EXPECTING MUCH IN THE WAY
OF ACCUMULATING SNOW FOR TWO REASONS. FIRST, THE REGION WILL
GENERALLY BE UNDER THE LEFT REAR QUADRANT OF AN UPPER LEVEL JET
THROUGH THIS TIME, WHICH SHOULD LIMIT LIFT. SECONDLY, IN ADDITION TO
THE COLD AIR ADVECTION, ALSO EXPECT CONSIDERABLE DRY AIR ADVECTION
IN THE BOUNDARY LAYER (SINGLE DIGIT DEW POINTS ARE POSSIBLE BY EARLY
THURSDAY MORNING), SO MOISTURE WILL BE LIMITED AS WELL. WE WILL BE
LOOKING FOR A LAKE EFFECT SNOW BAND FROM LERIE TO POSSIBLY STREAM
ACROSS THE APPALACHIANS INTO A PORTION OF E PA AND NJ.

&&

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

REMAINDER OF TODAY...VFR SCT-BKN AOA 4000 FT. IFR CONDS VCNTY KMIV
AND KACY SHOULD BECOME VFR BY 1630Z. WEST WIND GUST 20-25 KT.

TONIGHT...VFR CIGS MAY LOWER TO MVFR CONDS IN SNOW SHOWERS LATE.
WEST WIND GUSTS TO 20 KT.

OUTLOOK...

THURSDAY: MAINLY VFR, SOME BRIEF MVFR RESTRICTIONS IN ISOLATED
SNOW SHOWERS AND FLURRIES. NORTHWEST WINDS 15-25 KNOTS WITH HIGHER
GUSTS.

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 ISSUED...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.

THEREAFTER...WNW GALE GUSTS SPREADS 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.

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

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.

&&

.TIDES/COASTAL FLOODING...
COASTAL FLOODING BASICALLY IS DONE. WE CONTINUE THE ADVISORY FOR
THE NJ COAST, THOUGH ITS MARGINAL. THIS SHOULD BE THE LAST EPISODE
OF COASTAL TIDAL INUNDATION RELATED FLOODING THROUGH AT LEAST SUNDAY.

&&

.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 3F OF ZERO
(WIND IS THE EQUALIZER) ANYTIME FROM MIDNIGHT THROUGH 8 AM SUNDAY
EXCEPT COLDER KMPO. THIS HAS BEEN ADVERTISED BY THE GFS/ECMWF 2M
TEMPS CYCLICALLY FOR THE PAST 3 DAYS. THEREFORE, BEST CHANCE FOR
RECORD EQUALING OR EXCEEDING FOR VALENTINES DAY THE 14TH WOULD BE
KABE, KTTN AND KPHL.

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.

BE A GOOD IDEA TO CHECK ON ELDERLY/PETS DURING THE WEEKEND AND
CHECK-ENSURE HOME FUEL SUPPLIES CARRY YOU THROUGH THE WEEKEND.
AVOID GOING WITHOUT HEAT THIS WEEKEND. IT WONT TAKE LONG FOR WIND
DRIVEN COLD TO FREEZE WATER PIPES IN UNHEATED FACILITIES.

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 20 BELOW ZERO...POSSIBLY 25 BELOW IN
THE HILLS AND MOUNTAINS OF NORTHWEST NEW JERSEY AND NORTHEAST
PENNSYLVANIA.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...COASTAL FLOOD ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
     NJZ012>014-020-026.
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
NEAR TERM...DRAG/JOHNSON 1042
SHORT TERM...DRAG/JOHNSON
LONG TERM...GAINES
AVIATION...DRAG/GAINES 1042
MARINE...DRAG/GAINES 1042
TIDES/COASTAL FLOODING...1042
CLIMATE...1042



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