Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

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000
FXUS61 KPHI 261751
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1251 PM EST THU FEB 26 2015

.SYNOPSIS...
LOW PRESSURE SYSTEM WAS QUICKLY MOVING OUT TO SEA WELL EAST OF THE
MID ATLANTIC COAST. STRONG SPRAWLING ARCTIC HIGH PRESSURE CENTERED
IN MONTANA SYSTEM WILL CREST OF THE MID ATLANTIC STATES SATURDAY
THEN WEAKEN OFFSHORE SUNDAY. A COLD FRONT CROSSES THE AREA MONDAY.
LOW PRESSURE CROSSES OUR REGION ON TUESDAY INTO WEDNESDAY. ANOTHER
EXPANSIVE HIGH PRESSURE SYSTEM FOLLOWS.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE STORM SNOW OVER S NJ, E MD AND DE IS JUST ABOUT OVER AND
THE LAST OF THE WARNINGS WILL BE CANCELLED SHORTLY.

THE PUBLIC INFORMATION STATEMENTS WILL BE UPDATED INTO THIS
EVENING WITH FINAL TOTALS.

THE BAND OF SNOW SHOWERS OVER E PA AND NW NJ SHOULD DISSIPATE
EARLY THIS AFTERNOON.

WE`LL START SNOW PROBABILITIES AGAIN AT 430 PM FOR MORE UPCOMING
EVENTS.

OTHERWISE A NICE WINTERS AFTERNOON...ALBEIT 15 DEGREES OR SO ON
THE COLD SIDE.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM FRIDAY/...
TONIGHT, A WEAK MID LEVEL SHORT WAVE TROUGH LOOKS TO SIDESWIPE THE
NORTHWESTERN PORTIONS OF OUR REGION. AS A RESULT...LIGHT SNOW IS
POSSIBLE GENERALLY NORTH AND WEST OF THE PHILLY SUBURBS. MOISTURE
AVAILABILITY IS GOING TO BE PROBLEMATIC FOR THIS SYSTEM AS THERE IS
LITTLE CHANCE FOR ANY MOISTURE ADVECTION BEHIND TODAYS SYSTEM.
THEREFORE, ANY SNOW AMOUNTS SHOULD BE BELOW AN INCH.

AS FOR TEMPERATURES...STAYED CLOSE TO GUIDANCE AS MID LEVEL CLOUDS
SHOULD HELP TO LIMIT RADIATIONAL COOLING EVEN FOR LOCATIONS THAT
STILL HAVE SNOW PACK.

&&

.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
LAST PIECE OF MID-LEVEL ENERGY MOVES THROUGH THE REGION ON FRIDAY AS
THE BROAD SCALE TROUGHING FINALLY RELINQUISHING ITS GRASP ON OUR
REGION. THE MID-LEVELS TAKE ON MORE OF A ZONAL-ISH FLOW OVER THE
WEEKEND WITH THE NEXT EMBEDDED WAVE EXPECTED BY MONDAY FOLLOWED BY
RIDGING THROUGH THE REMAINDER OF THE PERIOD.

FRIDAY - SATURDAY...HIGH PRESSURE WILL BE SQUEEZING IN LATER ON
FRIDAY FROM THE WEST-NORTHWEST. JUST AHEAD OF THE RIDGING WILL BE A
LAST DITCH EFFORT BY THE BROAD TROUGH TO PUSH A DAMPENING SHORTWAVE
THROUGH THE REGION. WITH LIMITED AMOUNTS OF MOISTURE EXPECTED WE
CONFINED THE SLIGHT CHANCE POPS TO OUR WESTERN ZONES BEFORE DRYING
OUT LATER FRIDAY AFTERNOON. AT THIS POINT THE RIDGING WILL BE ABLE
TO EXERT ITSELF UPON THE AREA AND WE REMAIN DRY, BUT COLD, THROUGH
SATURDAY.

SUNDAY - MONDAY...ZONAL-ISH FLOW TURNS A BIT SHARPER AS THE BROAD
TROUGH RELOADS WELL TO OUR WEST. ANOTHER PASSING SHORTWAVE ALOFT
APPROACHES AND PUSHES A COLD FRONT THROUGH THE REGION  LATE SUNDAY
INTO MONDAY MORNING. OUT AHEAD OF THE FRONT TEMPERATURES ARE ABLE TO
MODIFY A BIT THANKS TO THE DEPARTING HIGH PRESSURE NOW OFF THE COAST
AND A LIGHT RETURN FLOW SETTING UP. WE CONFINED THE HIGHER POPS
UNTIL LATE SUNDAY NIGHT JUST AHEAD AND WITH THE FRONTAL PASSAGE.
DECENT AMOUNT OF THETA-E ADVECTION OCCURRING AHEAD OF THE FRONT WITH
ENOUGH LIFT FOR A LIGHT SNOW TO START BEFORE A WINTRY MIX/
CHANGEOVER, MOSTLY ACROSS THE SOUTHERN HALF OF THE CWA, BY MONDAY
MORNING. THE FRONT THEN MOVES THROUGH AND ALLOWS FOR ANOTHER SHOT OF
COOLER AIR AND MORE PRECIPITATION PHASE CHANGES.

TUESDAY - WEDNEDSAY...WITH THE COLD FRONT TO OUR EAST AND A BRIEF
SHOT OF HIGH PRESSURE BEHIND IT, THE NEXT SYSTEM, FORMING DEEP IN
THE SOUTH, BEGINS TO ENTER THE REGION FROM THE SOUTHWEST LATER ON
TUESDAY. A LIGHT ONSHORE FLOW WILL HELP TO ENHANCE THE LOW-LEVEL
MOISTURE FLUX WHEN COMBINED WITH A STRONG LOW-LEVEL SOUTHERLY SURGE
OF WARM/MOIST AIR. THIS EVENT COULD HAVE A COPIOUS AMOUNT OF
MOISTURE WITH IT, GIVEN ITS ORIGIN AND THE MODIFYING AIRMASS WE`LL
HAVE IN PLACE. TOO EARLY FOR PTYPE SPECIFICS BUT IT DOES APPEAR TO
BE A MIXED EVENT. IT SHOULD BE NOTED THAT SEVERAL TIMES THIS WINTER
THE NUMERICAL GUIDANCE HAS BEEN TOO STRONG WITH THE LOW PRESSURE AS
IT CROSSES THE MID-WEST AND THEREFORE OVER AMPLIFIES/WARMS THE LOW-
LEVELS. A SHIFT TO THE EAST AND A WEAKER SOLUTION WOULD LEAD TO LESS
MIXING.

&&

.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE,
KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS.

THIS AFTERNOON...VFR, NORTHEAST WIND GUSTS AROUND 20-25 KNOTS FOR
PHL AND ACY, LOWER ELSEWHERE. CAN NOT RULE OUT LINGERING FLURRIES
FOR ABE AND RDG, NOT IN TAF ATTM.

TONIGHT... VFR TO START WITH WINDS BECOMING LIGHT AND SHIFTING
MORE NORTHERLY. MVFR CONDITIONS STARTING AROUND 06Z WEST AND 09Z
EAST WITH A CHANCE OF LIGHT SNOW BY 11Z ACROSS THE REGION. SOME
UNCERTAINTY IN TIMING OF THE MVFR CEILINGS AND LIGHT SNOW. LITTLE
OR SNOW ACCUMULATION.

FRIDAY... MVFR IN THE MORNING WITH LINGERING LIGHT SNOW ENDING BY
16Z AT ALL TAF SITES, LITTLE OR NO SNOW ACCUMULATION. VFR IN THE
AFTERNOON WITH NORTHWEST WINDS AT OR UNDER 10 KNOTS. NOT MUCH IN
THE WAY OF GUSTS EXPECTED ATTM.

OUTLOOK...
FRIDAY NIGHT AND SATURDAY...MOSTLY VFR. NORTHERLY WINDS PREVAIL
AS HIGH PRESSURE NOSES IN FROM THE WEST.

SUNDAY - MONDAY...VFR TO START. CONDITIONS DETERIORATE LATE IN THE
DAY AS THE NEXT SYSTEM APPROACHES FROM THE WEST-SOUTHWEST. SOUTHERLY
WINDS EXPECTED.

&&

.MARINE...
SCA IN PROGRESS ALL WATERS EXCEPT MUCH OF UPPER DELAWARE BAY JUST
BELOW SCA. ON THE OCEAN WATERS A FEW GUSTS ABOVE 30 KT ARE POSSIBLE
EARLY THIS AFTERNOON. THEN BY EARLY THIS EVENING, WINDS SHOULD
DIMINISH BELOW 25KT, BUT SEAS ON THE OCEAN WILL BE SLOW TO DIMINISH.
THUS, HAVE SCA FOR THE OCEAN ZONES THROUGH 06Z FOR THE NORTHERN WATERS
AND 11Z FOR THE SOUTHERN WATERS.

OUTLOOK...

FRIDAY - SATURDAY...SUB-SCA EXPECTED, THOUGH PERSISTENT
NORTHEAST WINDS MAY ALLOW FOR BUILDING SEAS ACROSS OUR SOUTHERN
ZONES.

SUNDAY - MONDAY...POSSIBLE SCA CONDITIONS LATE ON SUNDAY AHEAD OF AN
APPROACHING COLD FRONT. INCREASING SOUTHERLY WINDS AND BUILDING SEAS
EXPECTED.

&&

.CLIMATE...
THE LONG CLIMATE SECTION WILL BE ADDED BACK AT 430 PM WHICH WILL
HAVE UPCOMING RECORD THRESHOLDS, MONTHLY COMPARISONS ETC.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EST FRIDAY FOR ANZ452>455.
     SMALL CRAFT ADVISORY UNTIL 1 AM EST FRIDAY FOR ANZ450-451.
     SMALL CRAFT ADVISORY UNTIL 5 PM EST THIS AFTERNOON FOR ANZ431.

&&

$$
SYNOPSIS...HEAVENER
NEAR TERM...DRAG/GAINES/JOHNSON
SHORT TERM...JOHNSON
LONG TERM...HEAVENER
AVIATION...GAINES/HEAVENER/JOHNSON
MARINE...HEAVENER/JOHNSON
CLIMATE...



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