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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KCTP 090618
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
118 AM EST MON DEC 9 2013

.SYNOPSIS...
A LIGHT WINTRY MIX OF PRECIPITATION WILL GRADUALLY TURN TO LIGHT
FREEZING RAIN OR FREEZING DRIZZLE OVERNIGHT AS HIGH PRESSURE AND
COLD AIR AT THE SURFACE SLOWLY RETREATS TO THE NORTHEAST ACROSS THE
NEW ENGLAND STATES. AFTER A SLIGHT MODERATION IN TEMPERATURES
MONDAY...GRADUALLY COLDER AIR WILL PUSH INTO THE STATE DURING THE
WEEK AS A PAIR OF COLD FRONTS TRACKS QUICKLY SOUTHEAST FROM THE
UPPER MIDWEST AND GREAT LAKES REGION.

&&

.NEAR TERM /UNTIL 8 AM THIS MORNING/...
-- Changed Discussion --
GENTLE WSWRLY ISENTROPIC UPGLIDE LEADING TO WIDESPREAD/LAYERED
CLOUD COVER...WITH PERSISTENT FREEZING DRIZZLE AND PERIODS OF
LIGHT FREEZING RAIN OVER THE SOUTHERN HALF OF THE STATE. PERIODS OF
LIGHT SNOW AND MIXED PRECIP WILL CONTINUE THROUGH MUCH OF THE NIGHT
ACROSS THE NRN MTNS...WITH LITTLE ADDITIONAL ACCUMULATION.

FAR SRN COUNTIES GETTING BRUSHED BY BAND OF LIGHT TO MODERATE
FREEZING RAIN ALONG THE MASON DIXON LINE. ADVISORY (<0.25")
AMOUNTS OF ICE STILL EXPECTED THERE...ALTHOUGH LOCATIONS CLOSE TO
THE MD BORDER MAY APPROACH ONE QUARTER INCH OF ICE BY EARLY MONDAY
MORNING.

CURRENT WINTER WEATHER ADVY LOOKS IN GOOD SHAPE.

TEMPS /CURRENTLY INTHE LOWER 20S ACROSS THE NRN AND WESTERN
MTNS...AND MID-UPR 20S THROUGHOUT THE LOWER/MID SUSQ
VALLEY...WILL SLOWLY CREEP UP OVERNIGHT...REACHING 27-31F BY
DAYBREAK.
-- End Changed Discussion --

&&

.SHORT TERM /8 AM THIS MORNING THROUGH 6 PM TUESDAY/...
RAIN/FZRA IN THE SE EARLY MONDAY WILL LIKELY PUSH EAST AS FLOW GOES
DECIDEDLY WEST AT THE SFC. LINGERING POCKETS OF -FZDZ WILL COULD
PERSIST THROUGHOUT THE CENTRAL AND NRN MTN AREA UNTIL AROUND NOON.

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 /TUESDAY 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 /06Z MONDAY THROUGH FRIDAY/...
A MOIST SERLY FLOW RIDING OVER COLD AIR AT GROUND LEVEL WILL
PRODUCE PERIODS OF FZDZ ACROSS MUCH OF CENTRAL PA OVERNIGHT. AN
AREA OF LOW PRESSURE PASSING SOUTH OF THE STATE WILL PRODUCE A
SOMEWHAT HEAVIER PERIOD OF FZRA ACROSS THE THE SOUTHEAST PART OF
THE STATE OVERNIGHT. APART FROM THE FREEZING PRECIP...WIDESPREAD
IFR/LIFR CIGS APPEAR ALMOST CERTAIN OVERNIGHT...AS THE
INCREASINGLY MOIST SE FLOW ASCENDS THE HIGHER TERRAIN OF CENTRAL
PA.

LATEST MDL DATA INDICATES THE FZRA/FZDZ WILL TAPER OFF BY LATE
AM...AS THE LOW PRESSURE SYSTEM PASSES OFF THE E COAST.
HOWEVER...LIGHT WINDS AND LACK OF MIXING COULD POTENTIALLY ALLOW
IFR CIGS TO PERSIST INTO EARLY AFTN AS THE 21Z SREF DATA
SUGGESTS. BY LATE MON AFTN...EXPECT IMPROVING FLYING CONDS AS
SHIFTING WINDS TO THE WEST USHER IN DRIER AIR. 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 BY LATE IN THE DAY.

OUTLOOK...
TUE...AM SNOW/LOW VSBYS POSSIBLE...MAINLY SOUTH.
WED...SHSN/LOW VSBYS POSSIBLE AT KBFD.
THU-FRI...NO SIG WX EXPECTED.

&&

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

&&

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