-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KCTP 261549
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1049 AM EST MON JAN 26 2015

.SYNOPSIS...
CLIPPER WILL WEAKEN OVER THE CENTRAL APPALACHIANS TODAY...AS
SECONDARY COASTAL STORM TAKES SHAPE SOUTH OF NEW ENG. THE COASTAL
STORM WILL RAPIDLY INTENSIFY TONIGHT AND TUESDAY...AS IT TRACKS
EAST OF NEW ENG. HIGH PRESSURE WILL BUILD OVER THE REGION FOR THE
MIDDLE OF THE WEEK...FOLLOWED BY AN ALBERTA CLIPPER THURSDAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
INCREASING 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 ARE NOT YET REAPING THE BENEFIT
AND ARE IN A RELATIVE LULL THIS MORNING. BASED ON REGIONAL RADAR
MOSAIC AND HI RES MODEL TRENDS...EXPECT THE LOWER SUSQ TO FILL
BACK IN WITH LIGHT SNOWFALL BY LATE MORNING/MIDDAY. STORM TOTAL
SNOWFALL FORECASTS ALREADY TOOK THIS INTO ACCOUNT...SO NO
ADJUSTMENTS NEEDED TO FORECAST AMOUNTS...BUT DID ADJUST THE NEAR
TERM POPS TO REFLECT THE LULL FOR THE NEXT FEW HOURS.

OVERALL...WIDESPREAD LIGHT SNOW WILL CONTINUE TO FALL OVR CENTRAL
PA THIS AFTERNOON ALONG 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.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
ADDITIONAL SHORTWAVE DIVING INTO BASE OF DEEPENING TROF WILL
SUPPORT ADDITIONAL LIGHT SNOW TONIGHT...FOCUSED ALONG INVERTED SFC
TROF AND PLUME OF HIGHER PWATS OVR THE ALLEGHENY AND SC MTNS. ALL
LATEST GUIDANCE INDICATES COASTAL STORM WILL BE TOO FAR EAST TO
HAVE A DIRECT IMPACT ON CENTRAL PA. MDL 7H FGEN FIELDS INDICATE
ASSOC DEFORMATION BAND SNOW WILL REMAIN WELL EAST OF OUR CWA.
BLEND OF LATEST MDL QPF SUPPORTS AN ADDITIONAL 1-2 INCHES
OVERNIGHT...MAINLY ACROSS THE CENTRAL AND ALLEGHENY MTNS.

DWINDLING MTNS SNOW SHOWERS EXPECTED TUESDAY...AS NORTHERLY FLOW
IN WAKE OF DEPARTING COASTAL LOW DRAWS MUCH DRIER AIR INTO CENTRAL
PA. TIGHT PRES GRADIENT IN WAKE OF STORM WILL PRODUCE GUSTY WINDS
ACROSS THE AREA AND 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 SUNDAY/...
FAIR AND CHILLY WED EXPECTED WED...AS HIGH PRES BUILDS OVR THE
AREA. MED RANGE GUIDANCE STILL INDICATES A CHANCE OF SNOW
THURS/THU NIGHT WITH NEXT IN SERIES OF CLIPPERS. BULK OF MED RANGE
GUIDANCE TRACKS THE SFC LOW NORTH OF PA...LIKELY RESULTING IN
MINIMAL ACCUMS ACROSS OUR AREA. ECENS SHOWS A DEEPENING UPPER LVL
TROF OVR THE EASTERN CONUS BY NEXT WEEKEND...OFFERING NO RESPITE
FROM THE COLD WX.

&&

.AVIATION /16Z MONDAY THROUGH FRIDAY/...
15Z TAFS SENT. MADE SOME CHANGES. WHILE CONDITIONS MAY BE NOT
THAT BAD AT TIMES...AND SKIES COULD TRY TO CLEAR ACROSS THE
FAR SOUTH...LIKE BEDFORD COUNTY...CONCERN IS FOR MORE SNOW
INTO TUESDAY MORNING...AS DEEP COASTAL STORM TAKES OVER...AND
INVERTED TROUGH REMAINS NEAR OR ACROSS CENTRAL PA. STARTING TO
SEE MORE IN THE WAY OF CONVECTIVE RETURNS ON THE LWX RADAR NEAR
BWI...HARD TO SEE THE LIGHTER SNOW ACROSS OUR SE AREAS LIKE
LNS...GIVEN THE COLDER AND DRIER AIRMASS IN PLACE NOW.

EARLIER DISCUSSION BELOW.

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
AFTERNOON 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...

TUE...AREAS MVFR IN SHSN WEST...GENERALLY VFR EAST. BREEZY N WIND.

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.

&&

.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-
028-041-046-049>053-056-057-063.

&&

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