Area Forecast Discussion
Issued by NWS State College, PA

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000 FXUS61 KCTP 262140 AFDCTP AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE STATE COLLEGE PA 440 PM EST WED NOV 26 2014 .SYNOPSIS... AN INTENSE STORM SYSTEM WILL QUICKLY MOVE UP THE MID ATLANTIC COAST INTO NEW ENGLAND THIS EVENING...AS A WIDESPREAD MODERATE TO HEAVY SNOW TAPERS OFF FROM WEST TO EAST ACROSS PENNSYLVANIA. ANOTHER SHOT OF COLDER AIR WILL FOLLOW FOR THE END OF THE WEEK ALONG WITH SCATTERED MAINLY LIGHT SNOW SHOWERS. TEMPERATURES MODERATE LATE WEEKEND INTO EARLY NEXT WEEK. && .NEAR TERM /UNTIL MIDNIGHT TONIGHT/... AT 4PM...THE WORST OF THE SNOW IS OVER FOR MOST OF CENTRAL PA...BUT BANDS OF MODERATE TO HEAVY SNOW WILL PERSIST FOR ANOTHER 1-2HRS IN THE EAST CENTRAL COUNTIES MAINLY EAST OF A LINE FROM LEWISTOWN TO WILLIAMSPORT. LIGHTER SNOWS WILL GRADUALLY TAPER OFF FROM THE WEST OVER THE NEXT SEVERAL HOURS. FOR NOW...WILL CONTINUE THE WARNINGS/ADVISORIES THOUGH THESE ALMOST CERTAINLY WILL BE CANCELLED BY EARLY/MID EVENING. THE CULPRIT FOR THE ACCUMULATING SNOWS AND POOR TRAVEL CONDITIONS IS AN INTENSE LOW CENTERED OFF THE COAST OF WALLOPS ISLAND VA ALONG WITH A NEGATIVELY TILTED TROUGH SWINGING OVERHEAD AND A VERY POTENT 150+ KT JET WHO/S N/S AXIS IS GRADUALLY SHIFTING EASTWARD ACROSS PA TO AND WILL BE ALIGNED WITH THE EASTERN SEABOARD BY 03Z THU. THOUGH THIS SURFACE LOW WILL CONTINUE TO DEEPEN...ITS TRACK OFF THE NJ COAST AND INTO NEW ENGLAND /ALONG WITH GENERAL RULE OF PRECIP WINDING DOWN RAPIDLY WHEN STORMS REACH THEN EXCEED OUR LATITUDE/ WILL SHIFT POTENTIAL FOR HEAVIEST SNOWS OFF TO OUR NE...ESP AS UPPER SUPPORT FROM THE TROUGH SLIDES BY IN THE NEXT FEW HOURS. SO...OUTSIDE OF A BAND IN EC PA THE ACCUMULATING SNOWS ARE NEARLY OVER AND SNOW WILL CONTINUE TO LIGHTEN HEADING INTO THIS EVENING. KEEP UP WITH THE LATEST SNOWFALL REPORTS IN OUR PHLPNSCTP PRODUCT...OR SUBMIT YOUR OWN ON OUR FACEBOOK PAGE. && .SHORT TERM /MIDNIGHT TONIGHT THROUGH THURSDAY NIGHT/... BY MIDNIGHT...TRANSITION TO COLD ADVECTION PATTERN WITH NW FLOW WILL BRING THE USUAL GENERALLY LIGHT LEFTOVER SNOW SHOWER ACTIVITY TO WESTERN HIGHER TERRAIN. THIS WILL CONTINUE INTO THU AND THU NIGHT...AND WILL BECOME A BIT MORE NUMEROUS AS A NOTABLE SHORTWAVE SLIDES THROUGH THE FLOW - THOUGH MOISTURE IS LIMITED. THE AIR THAT WILL MOVE IN BEHIND OUR STORM WILL BE COLDER BUT NOT ESPECIALLY SO...WITH LOWS IN THE 20S AND HIGHS IN THE 30S /ONLY BE A TAD BELOW NORMAL/. && .LONG TERM /FRIDAY THROUGH WEDNESDAY/... ANOMALOUSLY LOW HEIGHTS OVER THE EASTERN US EARLY IN THE PERIOD WILL FLATTEN OUT INTO A BROAD ZONAL FLOW DURING THE WEEKEND. THIS WILL PROMPT A WARM-UP AS THE CYCLONE TRACK SHIFTS TOWARD THE GREAT LAKES AND HIGH PRESSURE MOVES OFF TO OUR SOUTHEAST. THE SHOT OF COLD AIR THAT WILL MOVE INTO THE REGION IN THE WAKE OF OUR STORM WILL BEGIN MODERATING BY SATURDAY...WITH READINGS IN THE MILD RANGE TAKING OVER BY SUNDAY. MODELS IN DECENT AGREEMENT IN DROPPING A WEAK COLD FRONT THROUGH THE AREA SOMETIME SUNDAY NIGHT OR MONDAY. THIS WILL BE THE BEST CHANCE OF PRECIP DURING THE PERIOD...AND EVENTUALLY COOL US OFF A BIT FOR EARLY NEXT WEEK. && .AVIATION /22Z WEDNESDAY THROUGH MONDAY/... 21Z TAFS SENT. MADE SOME ADJUSTMENTS...WILL CONTINUE TO DO SO. HEAVIER BANDS OF SNOW STARTING TO MOVE EAST OF THE AREA. CONDITIONS STARTING TO IMPROVE SOME. EARLIER DISCUSSION BELOW. LOW PRESSURE OFF THE CAROLINA COAST WILL CONTINUE TO PRODUCE PERIODS OF LIGHT TO MODERATE SNOW OVER CENTRAL PA INTO THE EARLY EVENING HOURS. HOWEVER...CIGS AND VSBYS ARE GENERALLY IMPROVING ATTM AS THE HEAVIEST SNOW BANDS HAVE MOVED NORTH OF THE STATE. EXPECT LOW CIGS TO PERSIST OVER THE WRN 1/3 OF THE AREA TONIGHT WITH IMPROVEMENTS TO VFR ELSEWHERE. AFTER 03Z THURSDAY...CIGS AND VSBYS SHOULD IMPROVE...BUT SHOULD REMAIN MVFR AT MOST TAF SITES LATE WEDNESDAY NIGHT. NORTHWESTERLY FLOW BEHIND THE LOW SHOULD ALLOW IFR TO CONTINUE AT BFD AND JST. OUTLOOK... THU...IFR/MVFR WITH OCNL -SHSN WRN 1/3. VFR TO MVFR CIGS CNTRL/EAST. FRI...AM MVFR/-SHSN NW...OTHERWISE BCMG VFR. SAT-SUN...MAINLY VFR. ISOLD -SHRA PSBL. MON...COLD FROPA. MAINLY VFR. SCT -SHRA PSBL. && .CTP WATCHES/WARNINGS/ADVISORIES... WINTER STORM WARNING UNTIL 4 AM EST THURSDAY FOR PAZ019-042- 045-046-049>053. WINTER WEATHER ADVISORY UNTIL 4 AM EST THURSDAY FOR PAZ012-017- 018-037-041. WINTER STORM WARNING UNTIL MIDNIGHT EST TONIGHT FOR PAZ024>028- 033>036-056>059-063>066. && $$ SYNOPSIS...RXR NEAR TERM...RXR SHORT TERM...RXR LONG TERM...LA CORTE/GARTNER AVIATION...CERU/GARTNER/MARTIN

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