Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

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894
FXUS61 KPHI 101048
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
548 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/...
6 AM UPDATE...NO MAJOR CHANGES TO THE FORECAST. HIGH RESOLUTION
MODELS SHOW THE CURRENT BAND OF SNOW SHOWERS MOVING THROUGH OUR
AREA SHOULD DISSIPATE WITHIN THE NEXT 3 HOURS. BASED ON CURRENT
RADAR TRENDS, EXPECT LESS THAN ONE INCH OF ADDITIONAL SNOW
ACCUMULATION WITH THIS BAND.

PREVIOUS NEAR TERM DISCUSSION...
EARLY IN THE DAY, THE MAIN STORY WILL BE ICY SPOTS ON ROADS AND
WALKWAYS AS THERE WAS STANDING WATER IN MANY LOCATIONS LAST
EVENING, AND TEMPERATURES HAVE ALREADY DROPPED BELOW FREEZING FOR
MOST LOCATIONS. WE WILL CONTINUE THE SPECIAL WEATHER STATEMENT
(SPS) WARNING ABOUT THIS THROUGH AT LEAST THE MORNING COMMUTE.

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, NORTHWESTERLY 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.

&&

.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 /12Z WEDNESDAY THROUGH SUNDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.

A BAND OF SNOW SHOWERS WILL MOVE THROUGH THE DELAWARE VALLEY TAF
SITES (KPHL, KTTN, KPNE, AND KILG) AND KMIV THROUGH 14Z BEFORE
DISSIPATING. BRIEF IFR CONDITIONS ARE POSSIBLE WITH THIS SNOW, BUT
CONDITIONS SHOULD IMPROVE QUICKLY TO VFR BEHIND THESE SNOW
SHOWERS.

BY 15Z, ALL TAF SITES SHOULD BE BACK TO VFR. THOUGH WE COULD SEE
PERSISTENT MID LEVEL CEILINGS (5000 TO 8000 FT AGL) THROUGH THE
DAY AND EVEN TONIGHT, DO NOT EXPECT CEILINGS TO DROP BACK TO MVFR
ONCE THEY IMPROVE LATER THIS MORNING.

WESTERLY WIND GUSTS TO 25 KT WILL BE POSSIBLE FROM 14 TO 00Z, BUT
WINDS SHOULD DECREASE WITH SUNSET.

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...
SCA CONDITIONS FOR WINDS WILL CONTINUE ON THE COASTAL WATERS AND THE
DELAWARE BAY TODAY. SEAS HAVE BEEN STEADILY DECREASING OVERNIGHT,
AND MAY DROP BELOW 5 FT FOR MUCH OF THE DAY.

TONIGHT...HAVE EXTENDED THE SCA THROUGH THE OVERNIGHT HOURS AND
DELAYED THE START TIME OF THE GALE WATCH. MODEL SOUNDINGS FROM NAM,
RAP, AND GFS AND THE PROBABILISTIC WIND SPEED GUIDANCE OF THE NAEFS
AND GEFS SHOW A MINIMAL CHANCE FOR GALES OVERNIGHT. IN ORDER TO GET
GALE FORCE WINDS, THERE WOULD HAVE TO BE A VERY DEEP MIXING LAYER
WHICH SEEMS UNLIKELY GIVEN THE PERSISTENT MID LEVEL CLOUD COVER.
LIGHT FREEZING SPRAY WILL BE POSSIBLE ON THE BAY AND NEAR COASTAL
WATERS OVERNIGHT.

OUTLOOK...

THE GALE WATCH HAS BEEN EXTENDED INTO THURSDAY EVENING. FAIRLY
HIGH CONFIDENCE IS PRESENT FOR NORTHWEST WIND GUSTS NEAR AND JUST
OVER GALE FORCE THROUGHOUT MUCH OF THURSDAY AND INTO THE EARLY
EVENING. SEAS WILL ALSO BE AROUND FIVE FEET BEFORE DECREASING
LATER THURSDAY NIGHT. SCA NORTHWEST WINDS WILL CONTINUE INTO 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...
WITH A SHIFT TO OFF SHORE FLOW, AND LOWER ASTRONOMICAL TIDES, COASTAL
FLOODING CONCERNS ARE WINDING DOWN, WITH TWO EXCEPTIONS.

FIRST, FOR THE NORTHERN NEW JERSEY SHORE, WINDS WERE SLOWER TO SHIFT
TO WESTERLY AS COMPARED TO THE REST OF THE REGION. AS A RESULT,
WATER LEVELS AT SANDY HOOK AS WE APPROACH LOW TIDE ARE RUNNING
SLIGHTLY HIGHER THAN GUIDANCE. THUS, COULD SEE ONE MORE HIGH TIDE
CYCLE WITH MINOR COASTAL FLOODING THIS MORNING.

FOR CAROLINE, TALBOT, AND QUEEN ANNE`S COUNTY IN MD, EXPECT MINOR
COASTAL FLOODING WITH THE HIGH TIDE CYCLE THAT WILL OCCUR BY 9 AM
THIS MORNING.

&&

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

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

ADDITIONALLY...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...COASTAL FLOOD ADVISORY UNTIL 9 AM EST THIS MORNING FOR MDZ015-
     019-020.
MARINE...GALE WATCH FROM THURSDAY MORNING THROUGH THURSDAY EVENING FOR
     ANZ430-431-450>455.
     SMALL CRAFT ADVISORY UNTIL 6 AM EST THURSDAY FOR ANZ430-431-
     450>455.

&&

$$
SYNOPSIS...GAINES
NEAR TERM...JOHNSON
SHORT TERM...JOHNSON
LONG TERM...GAINES
AVIATION...GAINES/JOHNSON
MARINE...GAINES/JOHNSON
TIDES/COASTAL FLOODING...
CLIMATE...



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