Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

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000
FXUS61 KPHI 261838
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
138 PM EST MON JAN 26 2015

.SYNOPSIS...
LOW PRESSURE IN NORTH CAROLINA WILL TRACK TO THE VIRGINIA CAPES
BY NOON THEN INTENSIFY RAPIDLY IN ITS NORTHEAST TURN...NEARING
CAPE COD AT NOON TUESDAY AND THEN WEAKENING OFF TO NOVA SCOTIA ON
WEDNESDAY. HIGH PRESSURE FROM THE WEST IS FORECAST TO ARRIVE
WEDNESDAY NIGHT. A WEAK LOW IS EXPECTED TO FOLLOW AND PASS OVER
OUR REGION THURSDAY NIGHT AND EARLY FRIDAY. ANOTHER AREA OF HIGH
PRESSURE IS THEN ANTICIPATED FOR THE START OF NEXT WEEKEND.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF MID MORNING...A SFC LOW/TROF IS OVER WRN NC/VA BUT PRES
FALLS CONTINUE OFF THE MID ATLANTIC COAST AS LOW PRES STARTS TO
RE-FORM THERE. LIGHT SNOW IS BEING REPORTED AT NUMEROUS STATIONS
AROUND THE AREA BUT SO FAR AMOUNTS HAVE BEEN LIGHT...GENERALLY IN
THE 1 TO 2 INCH RANGE. LIGHT RAIN HAS BEEN REPORTED OVER SRN DE
WHERE TEMPS ARE IN THE UPPER 30S.

NO CHANGES WERE MADE TO THE FCST ATTM EXCEPT TO LOWER MAX TEMPS
OVER SRN DE TO LOWER 40S WITH CLOUDS, LIGHT PRECIP AND NELY WINDS.
STILL LOOKS LIKE MOSTLY LIGHT SNOW FOR TODAY WITH THE MAIN PART OF
THE STORM DEVELOPING TONIGHT INTO TUE. GUSTY NE WINDS ARE ALREADY
OCCURRING FROM PHL SOUTH...AND WINDS WILL GRADUALLY INCREASED
DURING THE DAY TODAY AS THE LOW STARTS TO DEEPEN OFFSHORE.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM TUESDAY/...
THE COASTAL SYSTEM WILL DEEPEN RAPIDLY OVERNIGHT AS IS MOVES FROM
OFF THE NC/VA COAST TO THE 40/70 BENCHMARK. STEADY/HVY SNOWS WILL
AFFECT MOSTLY THE ERN 2/3RD OF THE AREA WITH LIGHTER SNOWS AND
BLOWING SNOW OVER THE WRN/SWRN EDGES OF THE AREA. OUR SNOW TOTALS
ARE NOT MUCH DIFFERENT THAN THE ONES ISSUED SUN AFTERNOON...PERHAPS
A FEW INCHES LOWER IF ANYTHING. WARNING CRITERIA SNOW MAY OR MAY
NOT  OCCUR ACROSS THE FARTHEST WESTERN WARNING AREAS(CARBON AND
LEHIGH)...BUT BLOWING SNOW ACROSS THE HIGHER ELEVATIONS WILL MAKE
THINGS LOOK WARNING-LIKE. PLENTY OF TRAVEL IMPACTS ACROSS THE
REGION. HIGHEST TOTALS THRU 12Z NRN HALF OF NJ AND INTO EXTREME ERN
PA.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
***BLIZZARD COASTAL NEW JERSEY WILL BE ENDING TUESDAY AFTERNOON***

500 MB: DEEP OCCLUDED CYCLONIC CIRCULATION NEAR THE SOUTHERN NEW
ENGLAND COAST TUESDAY DEPARTS WITH RIDGING WEDNESDAY. THE NEXT
TROUGH FORMS SEWD TO THE EAST COAST THU-FRI. THEREAFTER THE HUDSON
BAY VORTEX SLIDES SOUTHEASTWARD INTO QUEBEC BY MONDAY.

TEMPERATURES: CALENDAR DAY AVERAGES WILL BE BELOW NORMAL TUESDAY
THROUGH SUNDAY WITH SEVERAL DAYS AROUND 10 DEGREES BELOW NORMAL.

FORECAST BASIS: UNLESS OTHERWISE NOTED WITHIN THE DAILIES. THIS
FORECAST IS A 50 50 BLEND OF THE 00Z/26 MAV/MET FOR TUESDAY-WEDNESDAY.
THE 00Z/26 MEX MOS WAS APPLIED WEDNESDAY NIGHT AND THURSDAY. THE
05Z/26 WPC D4-8 ELEMENTS OF DEWPOINTS/WIND/SKY/POP/MAX-MIN TEMPS
WERE NOT USED FOR THE LONGER RANGE...BUT WE DID ADJUST POPS HIGHER
THU AFTN INTO FRI MORNING FOR THE NEXT CLIPPER.

THE DAILIES...

TUESDAY...BENT BACK MID LVL FRONT AT 700-600 MB WITH FGEN EXCESSIVE
SNOWFALL RATES COASTAL CENTRAL AND NORTHERN NJ WILL BE WINDING
DOWN RAPIDLY TUESDAY AFTERNOON WITH SFC WINDS BACKING TO NW. IDEAL
SNOW GROWTH REGION NEAR 650MB NNJ NEWD WITH 1-3"/HR EXPECTED EVEN
FOR THE FIRST FEW HOURS AFTER SUNRISE TUESDAY. BUT...HOW FAR WEST
OF I 95 IS IT SNOWING TUESDAY IS STILL SOMEWHAT UNCERTAIN. USUALLY
WITH BANDING THERE ARE AREAS OF STRONG SUBSIDENCE AND DRYING IN
WHAT YOU WOULD OTHERWISE CONSIDER A SNOWY ENVIRONMENT. THOSE AREAS
OF DRYING CAN SURPRISE. THIS MESO METEOROLOGY WE`RE NOT TOO GOOD
AT REALISTICALLY AND RELIABLY DETAILING MORE THAN A FEW HOURS IN
ADVANCE. LETS THINK OF LIGHTER SNOW OCCURRING ACROSS THE REST OF
EASTERN PA AND THE DELMARVA TUE MORNING THEN DRYING OUT. NW WIND
GUSTS 25-35 MPH. CONSIDERABLE BLOWING AND DRIFTING OF THE SNOW
OCCURS, ESPECIALLY ACROSS NJ. ESTIMATING DRIFTS TO 4 FEET ARE
POSSIBLE IN EXPOSED REGIONS OF COASTAL NE NJ, WHERE SNOWFALL
EXCEEDS 18 INCHES.

TUESDAY NIGHT...CLEARING...WITH GUSTY NW WINDS 20 MPH. DRIFTING
SNOW CONTINUES, ESPECIALLY COASTAL NNJ

WEDNESDAY...MO/SUNNY WITH GUSTY NW WINDS 20-30 MPH.  DRIFTING SNOW
COASTAL NNJ.

THURSDAY INTO FRIDAY...A CLIPPER SYSTEM FROM THE NORTHWEST AND WEST
MAY BRING A SHOT OF LIGHT SNOW FROM LATE THURSDAY INTO FRIDAY. FOR
NOW WE ARE FORECASTING AN EVENT ...MODEST AMOUNTS UNDER 2 INCHES
IN THIS CF SITUATION AND FOR NOW MAINLY N OF I 78.

LATER FRIDAY INTO SATURDAY...ANOTHER SHOT OF COLD DRY AIR IS ANTICIPATED.

NEXT SUNDAY AND MONDAY...IT MIGHT GET INTERESTING AGAIN?  IT DOES
NOT LOOK NECESSARILY STRAIGHTFORWARD WITH THE SE EVOLUTION OF THE
POLAR VORTEX AND WHAT MIGHT DEVELOP TO OUR SOUTH AHEAD OF THE
POSSIBLE ARRIVAL OF BITTERLY COLD AIR HERE EARLY NEXT WEEK.

&&

.AVIATION /19Z MONDAY THROUGH SATURDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.

**HIGH IMPACT EVENT, ESPECIALLY TONIGHT AND TUESDAY MORNING**

THROUGH LATE-DAY...LIGHT SNOW IS EXPECTED TO CONTINUE ACROSS THE
AREA THROUGH THIS AFTERNOON, WITH MOSTLY MVFR TO POSSIBLE IFR
CONDITIONS. GUSTY NORTHEAST WINDS WILL PERSIST, WITH GUSTS MAINLY
BETWEEN 25 TO 30 KNOTS, ESPECIALLY FROM THE DELAWARE VALLEY EASTWARD
TO THE COAST.

EVENING/OVERNIGHT/EARLY TUESDAY...STEADILY DETERIORATING CONDITIONS
ARE EXPECTED THROUGH THIS PERIOD, WITH MODERATE TO AT TIMES HEAVY
SNOW DEVELOPING. SNOWFALL RATES OF ONE TO TWO INCHES PER HOUR ARE
POSSIBLE AT TIMES, ESPECIALLY THROUGH NJ AND THE DELAWARE VALLEY.
IFR TO LIFR CIGS AND VSBYS ARE EXPECTED. GUSTY NORTH-NORTHEAST WINDS
WILL CONTINUE, WITH GUSTS TO AROUND 30 KNOTS AT TIMES. AREAS OF
BLOWING SNOW ARE EXPECTED.

REST OF TUESDAY...AROUND MIDDAY AND INTO THE AFTERNOON, IMPROVEMENT
TO MVFR CONDITIONS ARE EXPECTED WITH SOME CONTINUED LIGHTER SNOW
ACROSS THE REGION. BLOWING AND DRIFTING SNOW WILL BE AN ISSUE,
THOUGH, AS WINDS BACK MORE TOWARD THE NORTHWEST WITH CONTINUED GUSTS
INTO THE 25 TO 30 KNOT RANGE. SOME LATE-DAY IMPROVEMENT TO VFR IS
EXPECTED, BUT TIMING IS A LITTLE UNCERTAIN.

OUTLOOK...
TUESDAY NIGHT...VFR SCT OR BKN AOA 4000 FT. NW WIND GUSTS 20 KT.

WEDNESDAY...VFR SCT AOA 4000 FT. NW WIND GUSTS 20-30 KT.

THURSDAY INTO FRIDAY MORNING...VFR TO START THURSDAY THEN A CHANCE
OF SNOW SHOWERS LATE THU OR EARLY FRI WHEN CONDITIONS MAY LOWER
INTO THE MVFR OR IFR RANGE FOR A TIME. SW WIND THU AFTN SHIFT NW
FRI.

&&

.MARINE...
SIGNIFICANT NOR`EASTER TO AFFECT THE WATERS LATER TODAY AND TONIGHT.
MARINE FLAGS WILL REMAIN AS THEY ARE WITH THE MORNING PACKAGE. STORM
WARNINGS FOR MOST OF THE COASTAL WATERS AND GALES FOR DEL BAY AND
THE SOUTHERN TWO COASTAL ZONES. BEGINNING AND END TIMES CONTINUE TO
LOOK GOOD.

OUTLOOK...
TUESDAY...A MARINE STORM WARNING IS IN EFFECT FOR OUR OCEAN WATERS
OFF NEW JERSEY TO START THE DAY. A GALE WARNING IS IN EFFECT FOR THE
WATERS OFF DELAWARE AND FOR DELAWARE BAY.  WINDS DMSHG IN THE AFTN.

TUESDAY NIGHT...LEFTOVER NW GALES DURING THE EVENING WITH SLOWLY
DIMINISHING WIND OVERNIGHT. FREEZING SPRAY.

WEDNESDAY...SMALL CRAFT ADVISORY CONDITIONS ARE EXPECTED WITH
FREEZING SPRAY.

WEDNESDAY NIGHT THROUGH THURSDAY...NO MARINE HEADLINES ARE
ANTICIPATED.

FRIDAY...AN SCA SHOULD EVENTUALLY BE NEEDED BY LATE FRIDAY AS A
NORTHWEST FLOW OF COLD AIR ADVECTION DEVELOPS BEHIND THE NORTHEASTWARD
DEPARTING CLIPPER LOW.

&&

.TIDES/COASTAL FLOODING...
COASTAL FLOODING...COASTAL FLOOD WATCHES WERE CONVERTED TO WARNINGS
WITH THE 330 AM FCST. WIDESPREAD MINOR WITH A FEW AREAS OF LOW-END
MODERATE TIDAL FLOODING EXPECTED. THE TIDE CYCLES TONIGHT AND TUESDAY
MORNING ARE THE MOST LIKELY ONE TO HAVE FLOODING CONCERNS...THE
GREATER THREAT OF MODERATE FLOODING BEING TONIGHTS MIDNIGHT HIGH TIDE
CYCLE.

&&

.CLIMATE...
RECORD (VULNERABLE) DAILY SNOW FALL FOR OUR LONG TERM CLIMATE
SITES. TUESDAY 1/27.

ACY 4.0 1946
PHL 4.1 1941
ILG 2.9 2004
ABE 8.0 1897

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...WINTER STORM WARNING UNTIL 6 PM EST TUESDAY FOR PAZ070-071-
     103>106.
     WINTER WEATHER ADVISORY UNTIL 3 PM EST TUESDAY FOR PAZ060-101-
     102.
     WINTER STORM WARNING UNTIL 3 PM EST TUESDAY FOR PAZ054-055-061-
     062.
NJ...WINTER STORM WARNING UNTIL 6 PM EST TUESDAY FOR NJZ001-007>010-
     015>019-021>025-027.
     COASTAL FLOOD WARNING FROM 11 PM THIS EVENING TO 7 AM EST
     TUESDAY FOR NJZ012>014-020>027.
     BLIZZARD WARNING UNTIL 6 PM EST TUESDAY FOR NJZ012>014-020-026.
DE...COASTAL FLOOD WARNING FROM 11 PM THIS EVENING TO 7 AM EST
     TUESDAY FOR DEZ002>004.
     WINTER WEATHER ADVISORY UNTIL 3 PM EST TUESDAY FOR DEZ001>004.
MD...WINTER WEATHER ADVISORY UNTIL 3 PM EST TUESDAY FOR MDZ008-012-
     015-019-020.
MARINE...STORM WARNING UNTIL 6 PM EST TUESDAY FOR ANZ450>453.
     GALE WARNING UNTIL 6 PM EST TUESDAY FOR ANZ430-431-454-455.

&&

$$
SYNOPSIS...DRAG
NEAR TERM...AMC/O`HARA
SHORT TERM...O`HARA
LONG TERM...DRAG
AVIATION...DRAG/KLINE/O`HARA
MARINE...DRAG/O`HARA
TIDES/COASTAL FLOODING...
CLIMATE...






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