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000
FXUS61 KCTP 261938
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
238 PM EST THU FEB 26 2015

.SYNOPSIS...
AN UPPER LEVEL TROUGH AND YET ANOTHER PUSH OF ARCTIC AIR WILL
MOVE EAST ACROSS THE STATE LATE TODAY THROUGH EARLY FRIDAY...
ACCOMPANIED BY MORE SNOW SHOWERS...WITH A SEVERAL HOUR PERIOD OF
STEADY SNOW ACROSS THE LAUREL HIGHLANDS LATE TODAY AND THIS
EVENING. A LARGE AREA OF HIGH PRESSURE WILL BUILD ACROSS THE AREA
FOR THE FIRST PART OF THE WEEKEND. THE PATTERN WILL THEN BECOME
RATHER STORMY WITH A FRONTAL BOUNDARY WAGGLING NORTH AND SOUTH
OVER THE AREA INTO MID WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
APPROACHING UPPER LEVEL SHORT WAVE AND ANOTHER ARCTIC CFRONTAL
BOUNDARY WILL BRING A FEW-SVRL HOUR PERIOD OF STEADY LIGHT SNOW TO
THE LAURELS LATE THIS AFTERNOON AND EVENING...WHILE SOME
INTERMITTENT LIGHTER SNOW AND SNOW SHOWERS DEVELOPS AND FALLS
THROUGH EARLY TONIGHT TO THE EAST OF THE INTERSTATE 99/RT220
CORRIDOR.

ACCUMS WILL RANGE FROM JUST A LIGHT COATING AT LOWER ELEVATIONS
ACROSS THE SOUTHERN THIRD TO HALF OF THE CWA...TO BETWEEN 1 AND 2
INCHES ACROSS THE LAUREL HIGHLANDS.

AS WINDS BACK AROUND FROM THE NORTH TO NW THROUGH TONIGHT...A
BETTER LLVL UPSLOPE COMPONENT AND STEEPER LOW-MID LEVEL LAPSE
RATES WILL MEAN THAT SNOW SHOWERS WILL CONTINUE ACROSS THE
LAURELS...WHILE THE LIGHT SNOW EARLY ON...TRANSFORMS TO FLURRIES
AND ISOLATED -SHSN TO THE SE OF THE ALLEGHENY FRONT.

LOW TEMPS TONIGHT WILL RANGE FROM THE SINGLE DIGITS BELOW ZERO
ACROSS THE NW MTNS...TO THE TEENS IN THE SE. THE GENERALLY LIGHT NORTH
TO NW WIND WILL REDUCE THE APPARENT TEMP BY ABOUT 7-10F FROM THE
ACTUAL AIR TEMPS.

&&

.SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/...
THE UPPER TROUGH AXIS FLATTENS OUT AN MOVES ACROSS THE REGION
FRIDAY. AREAS OF STRATO CU AND ISOLATED TO SCTD MORNING SNOW
SHOWERS WILL DISSOLVE AS ANOMALOUSLY STRONG 1040-1045 MB SFC HIGH
PRESSURE BUILDS EAST INTO THE COMMONWEALTH FROM THE OHIO VALLEY.

HIGH TEMPS FRIDAY WITH A WEST TO NW WIND OF 5-10KTS WILL VARY
FROM JUST 8-12F ACROSS THE NW MTNS AND LAURELS...TO THE LOWER AND
MID 20S ACROSS THE LOWER SUSQ VALLEY.

CLEAR SKIES AND LIKELY THE COLDEST NIGHT UNTIL NEXT WINTER WILL
OCCUR FRIDAY NIGHT AS THE CENTER OF HIGH PRESSURE MOVES OVER PENN.

LOW TEMPS EARLY SATURDAY WILL BE 10-15F BELOW ZERO ACROSS THE
WESTERN MTNS...AND 5 BELOW TO 5 ABOVE ELSEWHERE. THE COLDEST RURAL
VALLEYS IN NW AND NCENT PENN COULD SEE THE MERCURY SETTLE TO
AROUND -20F AT 11-12Z SATURDAY.

&&

.LONG TERM /SATURDAY THROUGH THURSDAY/...
HIGH PRESSURE BUILDING INTO THE REGION DRIES THINGS OUT FOR EARLY
WEEKEND. AS IT MOVES TO THE ATLANTIC COAST ON SUNDAY...RETURN FLOW
SHOULD DRAW MOISTURE UP INTO THE OHIO VALLEY. MOISTURE WILL
OVERSPREAD THE OHIO VALLEY AND SLIDE ACROSS PA IN A DISORGANIZED
PRECIPITATION PATTERN. ANOTHER BLAST OF ARCTIC AIR THEN SHOVES
THAT SYSTEM OFF TO THE EAST.

AS A SOUTHWEST UPPER FLOW SETS UP NEXT WEEK...MOISTURE WILL SPREAD
TOWARD THE AREA BY LATER TUESDAY. COLD AIR IN PLACE OVER THE
RIDGE AND VALLEY REGION COULD LEAD TO THE INITIAL PRECIPITATION
SHIELD TO BE SLEET OR FREEZING RAIN. THE BULK OF THE MOISTURE DOES
APPEAR TO TRAVEL SOUTH OF PA AT THIS TIME. UNSETTLED CONDITIONS
WILL LINGER THROUGH LATE WEEK AS THE AREA WOBBLES AROUND THE ZERO
DEGREE H850 LINE..

&&

.AVIATION /19Z THURSDAY THROUGH TUESDAY/...
EXPECT MAINLY VFR CLOUD BASES AND VSBYS ACROSS THE CENTRAL MTNS
AND SUSQ VALLEY TAF SITES TO DIP ONCLY DOWN INTO THE MVFR RANGE AS
AN UPPER LEVEL DISTURBANCE /AND ANOTHER PUSH OF ARCTIC AIR/
CROSSES THE REGION LATE TODAY AND EARLY TONIGHT WITH SCT-NUMEROUS
-SHSN DEVELOPING IN THE 20-23Z PERIOD.

MORE PERSISTENT MVFR CIGS AND VSBYS IN LIGHT SNOW WILL OCCUR ACROSS
THE WESTERN MTNS...WITH PERIODS OF IFR LATE THIS AFTERNOON
THROUGH EARLY TONIGHT. CONDITIONS WILL IMPROVE JUST A BIT AFTER
MIDNIGHT TONIGHT ACROSS THE LAURELS...WITH MAINLY VFR VSBYS AND
MVFR TO VFR CIGS DEVELOPING THROUGHOUT THE CENTRAL RIDGE AND
VALLEY REGION AND SUSQ VALLEY.

OUTLOOK...

FRI...EARLY AM LGT SNOW/VIS REDUCTIONS POSSIBLE...OTHERWISE VFR
WITH A 5-10KT WEST TO NW WIND.

FRI NIGHT AND SAT...NO SIG WX EXPECTED.

SUN...SNOW LIKELY NW MTNS. MIXED PRECIP POSSIBLE ELSEWHERE.

MON...MIXED PRECIP WITH CIG/VIS REDUCTIONS POSSIBLE...MAINLY AM.

&&

.CLIMATE...
THE COLDEST FEBRUARY ON RECORD IS STILL LOOKING LIKELY. MONTHLY
MEAN TEMPERATURES THROUGH THE 25TH...IPT 18.0...MDT 20.7.

THE CURRENT RECORD COLDEST FEBRUARY..IPT 19.3...MDT 21.4 BOTH SET
IN 1934.

SO FAR...THIS MONTH IS THE THIRD COLDEST EVER AT IPT...AND FOURTH
COLDEST EVER AT MDT.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...TYBURSKI
AVIATION...LAMBERT
CLIMATE...LAMBERT