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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KCTP 082300
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
600 PM EST SUN DEC 8 2013

.SYNOPSIS...
HIGH PRESSURE OVERHEAD IS RETREATING NORTHWARD. SNOW FROM THIS
STORM WILL TURN TO SLEET AND FREEZING RAIN OVER MUCH OF CENTRAL PA
THIS EVENING AND EARLY TONIGHT. SOUTHERN AREAS WILL LIKELY TURN TO
RAIN LATER TONIGHT. FREEZING RAIN WILL CONTINUE THROUGH EARLY
MONDAY MORNING BEFORE TAPERING OFF. AN ARCTIC FRONTAL PASSAGE
EARLY NEXT WEEK WILL DROP TEMPERATURES WELL BELOW NORMAL THROUGH
THE MIDDLE AND LATTER PART OF NEXT WEEK.

&&

.NEAR TERM /UNTIL 1 AM MONDAY MORNING/...
CRAZY INTENSE BAND ON THE MASON-DIXON LINE HAS NOW MOVED OFF TO
THE EAST. GENERALLY LIGHT TO MOD SNOW AND SLEET NOW GOING THRU THE
SRN HALF OF THE AREA. WHILE HEAVY SNOW OVER THE EXTREME SRN BORDER
OF OUR SRN-MOST COUNTIES MIGHT HAVE BEEN A CONCERN EARLIER...THE
PRECIP IS LIGHTENING UP SOME AND GOOD IR ENHANCEMENT IS NOW EAST
OF OH/WRN PA. CURRENT ADVY AREA IS STILL OK...WITH A GRADUAL
TRANSITION TO A VERY WARM-TOPPED AND LOW-CLOUD PROFILE BY
MIDNIGHT.

&&

.SHORT TERM /1 AM MONDAY MORNING THROUGH 6 PM MONDAY/...
LIGHT PRECIP WILL BE IN A GRADUAL TRANSITION ACROSS THE SOUTHERN
AREAS AROUND MIDNIGHT. THE SC MTS WILL HOLD THE COLD AIR LONGEST
- AS THE WARMER SFC TEMPS PINCH IN FROM SW AND SE AT THE SAME
TIME. PRECIP INTENSITY IS THEN BEST IN NRN HALF OF THE AREA FOR
THE REST OF THE NIGHT - BUT QPF REMAINS EXTREMELY MINIMAL...MAINLY
LESS THAN A TENTH OF AN INCH FROM MIDNIGHT TO THE END OF THE
EVENT. RAIN ACROSS THE SE WILL MAKE IT ALL A SLOPPY MESS OF SLUSH
BY THE MORNING. SFC TEMPS RISING WILL LEAD TO A FOGGY AND DRIZZLY
OVERNIGHT. RAIN IN THE SE EARLY MONDAY WILL LIKELY PUSH EAST AS
FLOW GOES DECIDEDLY WEST AT THE SFC. GOOD COLD ADVECTION WILL
START TO PUSH THE TEMPS DOWN ACROSS THE WEST RATHER QUICKLY LATE
MONDAY. MOS DOES HINT AT A FLAT LINE OR DROP IN TEMPS FOR THE AFTN
IN BFD. BUT THE REST OF THE AREA WILL LIKELY WARM UP SLIGHTLY
DURING THE DAY. SCT --SHSN WILL DEVELOP AS THE COLD AIR RUSHES IN
OVER THE NW.

&&

.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
LITTLE IN THE WAY OF A BREAK IN THE PRECIPITATION AS WE MOVE NTO
THE EXTENDED FORECAST. THE MAIN FRONT SLOWS TO A CRAWL OVER THE
MID ATLANTIC STATES MONDAY NIGHT AS A WAVE OF LOW PRESSURE TRACKS
NORTHEAST ALONG THE BOUNDARY. DIFFERENCE IN MODEL OPINIONS ON THE
NORTHERN EXTENT OF THE PRECIP SHIELD BUT EVEN IF IT REMAINS
SOUTH...SOME LIGHT SNOW OR FLURRIES STILL POSSIBLE OVER SOUTHEAST
PA. LEFT AMOUNTS ON THE LIGHT SIDE...TO BE REFINED AS CONFIDENCE
INCREASES.

AS THIS SYSTEM PULLS EAST ON WEDNESDAY...ARCTIC AIR SURGES INTO THE
REGION FOR THE REST OF THE WORK WEEK. NORTHWEST FLOW ALOFT AND
AROUND BUILDING HIGH PRESSURE AT THE SURFACE WILL BRING LOWS IN
THE SINGLE DIGITS AND TEENS FOR THU AND FRI MORNING...AND HIGHS
MAINLY IN THE 20S.

THIS WEEKEND...FLOW TURNS WESTERLY BRINGING GRADUAL MODERATION TO
TEMPERATURES. ANOTHER WAVE OF LOW PRESSURE PROGGED FOR LATER SAT
INTO SUNDAY WITH LIGHT PRECIPITATION POSSIBLE.

&&

.AVIATION /00Z MONDAY THROUGH FRIDAY/...
-- Changed Discussion --
FIRST WAVE OF LOW PRESSURE IS PUSHING OFF THE MID ATLANTIC COAST
THIS EVENING...BRINGING AN END TO THE STEADY SNOW ACROSS SOUTHERN
PA. ANOTHER WAVE OF LOW PRESSURE...GATHERING OVR THE SOUTHERN
APPALACHIANS THIS EVENING...COULD SPREAD A PERIOD OF FZRA ACROSS
SOUTHERN PA MON MORNING. HOWEVER...IN THE NEAR TERM THE BIGGEST
AVIATION CONCERN WILL BE LOW CIGS/VSBYS DUE TO AN INCREASINGLY
MOIST SERLY FLOW IN THE LOW LVLS. SREF OUTPUT AND MDL SOUNDINGS
SUPPORT WIDESPREAD IFR CONDS LATER TONIGHT.

BY MON AFTN...EXPECT IMPROVING FLYING CONDS AS SECOND WAVE OF LOW
PRESSURE EXITS THE AREA AND A DRIER WESTERLY FLOW OVERSPREADS THE
STATE. RESIDUAL LOW LVL MOISTURE ASCENDING THE W MTNS COULD
POTENTIALLY ALLOW LOWS CIGS TO PERSIST AT KBFD AND KJST THRU
EVENING. HOWEVER...A RETURN TO EITHER MVFR OR VFR APPEARS NEARLY
CERTAIN ELSEWHERE ACROSS CENTRAL PA.

OUTLOOK...
TUE...SCT SHSN FAR NW AND -SN POSS SE.
WED-THU...NW FLOW. MVFR/IFR SCT -SHSN NW.
FRI...VFR.
-- End Changed Discussion --

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 10 AM EST MONDAY FOR PAZ004>006-
010>012-017>019-024>028-033>037-041-042-045-046-049>053-
056>059-063>066.

&&

$$
SYNOPSIS...DANGELO
NEAR TERM...DANGELO
SHORT TERM...DANGELO
LONG TERM...RXR/TYBURSKI
AVIATION...DANGELO/FITZGERALD