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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KCTP 262132
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
432 PM EST MON JAN 26 2015

.SYNOPSIS...
PERIODS OF LIGHT SNOW WILL DECREASE ACROSS CENTRAL PENNSYLVANIA
TONIGHT AS A STRONG COASTAL STORM TRACKS TOWARDS NEW ENGLAND
TONIGHT. THE COASTAL STORM WILL RAPIDLY INTENSIFY TONIGHT AND
TUESDAY...AS IT TRACKS EAST OF NEW ENGLAND. HIGH PRESSURE WILL
BUILD OVER THE REGION FOR THE MIDDLE OF THE WEEK...FOLLOWED BY AN
ALBERTA CLIPPER THURSDAY.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
ADDED TIOGA CO TO THE ADVY AS SNOW SHOULD CONTINUE TO FALL THERE
FOR ANOTHER FEW HRS AND THEY ARE ALREADY PUSHING 3-5 INCHES OF
SNOW OFF THEIR CARS. HOWEVER...THE RAP AND HRRR BOTH SLIDE THE BIG
BAND OFF TO THE EAST SLIGHTLY - SO LESSER CHANCE FOR SULLIVAN CO
PA TO GET TOO MUCH MORE. JUST UPPED POPS SLIGHTLY TO JUST BELOW
101 PERCENT IN THE CENTRAL AND WEST.

PREV...
DEFORMATION BETWEEN THE INVERTED SFC TROF OVER WESTERN AND
SOUTHWESTERN PA AND RAPIDLY DEVELOPING COASTAL LOW OFF OF
SOUTHEAST VA IS MAINTAINING CATEGORICAL POPS/SNOW ACROSS THE
LAURELS AND CENTRAL/WEST CENTRAL/NORTHWEST/NORTHERN MOUNTAINS
PRESENTLY. MY SOUTHEAST COUNTIES HAVE STARTED TO SEE SOME LIGHT
ACTIVITY BUT IT IS STILL REMOVED FROM THE BETTER DEFORMATION
ASSOCIATED WITH THE INVERTED TROF TO THE WEST AND THE INTENSIFYING
LOW TO THE EAST. LOWERED THE LOWER END OF SNOW FAR RANGES FOR THE
EAST IN WSW...GENERALLY 2 TO 5 INCHES EXPECTED OVERALL BEFORE
ACCUM SNOWFALL EXITS PA BY DAYBREAK TUE MORNING.

OVERALL HOWEVER...WIDESPREAD LIGHT SNOW WILL CONTINUE TO FALL OVR
CENTRAL PA THIS EVENING INTO LATE TONIGHT ALONG THE AXIS OF DEEP
EASTERLY FLOW BTWN LOW TO THE SOUTH AND HIGH PRES OVR NEW
ENGLAND...FORCED LOCALLY BY THE INCREASING AFOREMENTIONED
DEFORMATION. HI RES NAM/HRRR/WRF ARW ALL SUPPORT AN ADDITIONAL 1-3
INCHES TODAY...WITH THE HIGHEST AMTS ACROSS THE CENTRAL
MTNS/ALLEGHENIES. KEEPING HEADLINES AS IS FOR NOW BUT SOME MAY
NEED TO BE EXTENDED OVERNIGHT DEPENDING UPON WHERE THE DEFORMATION
PROPOGATES. HRRR INDICATES A SOUTHWEST SHIFT TO THE FORCING AFTER
03Z...AS THE PARENT COASTAL CIRCULATION DOMINATES AND TAKES OVER
EFFECTIVELY DISRUPTING AND ELIMINATING THE DEFORMATION FORCING
SNOWFALL OVER CENTRAL PA BY 12Z.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/...
AS MENTIONED ABOVE...DEFORMATION SNOW SHOWERS SHOULD DWINDLE EARLY
TUESDAY...WHILE NNW FLOW IN WAKE OF DEPARTING COASTAL LOW DRAWS
MUCH DRIER AIR INTO CENTRAL PA. 25 TO 35KT NE WIND GUSTS WILL BE
FELT AS TIGHT PRES GRADIENT IS REALIZED IN WAKE OF STORM JUST
OFFSHORE OF SOUTHERN NEW ENGLAND COAST. AS PREVIOUSLY
MENTIONED...THERE IS THE POTENTIAL OF SOME BLOWING/DRIFTING...ESP
EASTERN PA WHERE BUKFIT SOUNDINGS SUPPORT GUSTS BTWN 30-35KTS. ENS
MEAN 925 TEMPS SUPPORT MAX TEMPS TUE FROM NR 20F OVR THE N
MTNS...TO ARND 32F ACROSS THE LOWER SUSQ VALLEY.

&&

.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
DEEP STORM WILL PULL AWAY FROM PA TUESDAY NIGHT. WITH WINDS
FROM THE NORTH...TOOK OUT SNOW SHOWERS FOR JST.

SKIES SHOULD CLEAR OUT BY WED MORNING.

MAIN CHANGE WAS WED NIGHT...DID LOWER TEMPS...BASED ON 12Z
MODEL RUNS...AND THAT WITH MAINLY CLEAR SKIES AND LIGHT
WINDS...EXPECT TEMPS TO DROP...WITH FRESH SNOW COVER.

NEXT SYSTEM WILL BRING SOME SNOW SHOWERS TO THE AREA LATER THU
INTO FRIDAY. THIS SYSTEM NOT LOOKING LIKE IT WOULD RESULT IN
A COASTAL REAL NEAR THE COAST.

COLDER AIR FOR FRIDAY NIGHT.

WEEKEND NOT LOOKING TOO BAD...COLDER AIR WILL TRY TO BUILD IN
EARLY NEXT WEEK.

&&

.AVIATION /22Z MONDAY THROUGH SATURDAY/...
REDUCTIONS CONTINUE REGIONWIDE AS INVERTED TROUGH LINGERS OVER
CENTRAL PA /AND AS DEVELOPING NOR`EASTER BEGINS TO DEEPEN OFF MID
ATLANTIC COAST/. EXPECT WIDESPREAD LIGHT SNOW TO CONTINUE THIS
INTO TONIGHT WITH VSBYS VARYING FROM 1-4SM AND CIGS OF MVFR- IFR
SETTLING BACK TOWARD A MORE ROBUST IFR DECK. NE WINDS WILL BE
AROUND 10 MPH TODAY...AND PICK UP A BIT TO 10-15 MPH IN THE LOWER
SUSQ TONIGHT AS STORM DEEPENS TO THE EAST AND SYNOPTIC FLOW
INCREASES.

IMPROVING CONDITIONS ON TUES AS HIGH PRESSURE BUILDS IN. SHOULD
SEE VFR CONDITIONS IN CENTRAL AND EAST...WITH MVFR CIGS IN NW FLOW
UNDER SUBSIDENCE INVERSION IN THE WESTERN HIGHER TERRAIN. NORTH
WIND WILL BE BREEZY...PRODUCING SPEEDS OF 10-20 MPH.

OUTLOOK...

WED...VFR WITH NO SIG WEATHER EXPECTED.

THU...VFR TO START...WITH LATE DAY RESTRICTIONS SPREADING IN FROM
THE WEST.

THU NIGHT-FRI...WIDESPREAD IFR/MVFR IN SNOW.

SAT...MAINLY VFR.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 7 AM EST TUESDAY FOR PAZ004>006-
010>012-017>019-024>026-033>036-045-058-059-064>066.
WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR PAZ027-
028-037-041-046-049>053-056-057-063.

&&

$$
SYNOPSIS...DEVOIR/FITZGERALD
NEAR TERM...DANGELO/DEVOIR/FITZGERALD
SHORT TERM...DEVOIR/FITZGERALD
LONG TERM...MARTIN
AVIATION...DEVOIR/MARTIN