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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KCTP 121838
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
238 PM EDT WED MAR 12 2014

.SYNOPSIS...
A STRONG LATE-WINTER STORM WILL IMPACT THE AREA TODAY...FOLLOWED
BY COLD AND BLUSTERY CONDITIONS WITH WELL-BELOW NORMAL
TEMPERATURES FOR THURSDAY. TEMPERATURES WILL REBOUND TO NEAR
SEASONAL LEVELS FRIDAY INTO THE WEEKEND...AHEAD OF A FRONTAL
SYSTEM PUSHING SOUTHEAST FROM THE GREAT LAKES. THIS FRONT MAY
PRODUCE SOME RAIN OR SNOW SHOWERS ON SATURDAY.

&&

.NEAR TERM /THROUGH TONIGHT/...

-- Changed Discussion --
THE COLD AIR FINALLY GOT INTO THE NORTHERN TIER COUNTIES AS DID
THE SNOW. LAST LOOK BRADFORD WAS 29F AND SNOWING. SNOW AND COLD
AIR WILL CONTINUE TO SLOWLY CHANGE RAIN TO SNOW ACROSS THE
NORTHERN TIER THIS AFTERNOON.

FARTHER SOUTH...A MODEST BAND OF INTENSE SHOWERS HAS DEVELOPED IN
THE WARM AIR ON THE WEST SIDE OF THE MOUNTAINS. IT IS A FEW TENS
OF MILES AHEAD OF THE REAL COLD AIR AND IT CAN PRODUCE BRIEF
STRONGER RAIN SHOWERS AND CAN BRING DOWN GUSTY WINDS...WINDS ARE
OVER 60KTS ABOVE ABOUT 5-6KFT. METARS SHOW THESE CONVECTIVE
ELEMENTS CAN BRING DOWN 35 TO 40 MPH WINDS. JUST PAST KJST ABOUT
230 PM.

THE LOW AT 18Z WAS OVER SOUTHWESTERN PA CHUGGING EASTWARD. CENTRAL
AND SOUTHERN AREAS WILL SEE THIS FRONTAL BOUNDARY AND LINEAR
ENHANCED CONVECTION SWEEP ACROSS THE STATE OVER THE NEXT 2-3 HOURS.

EXPECT SNOW IN NORTHERN TIER TO BEGIN ACCUMULATE. THERE ARE TWO
SHOTS AT SNOW IN NW PA...WITH THE BAND JUST NW OF THE LOW AND THE
LARGER DEFORMATION BAND OVER NE OHIO AND LAKE ERIE. HAD TO BRING
SNOW TOTALS DOWN CONSIDERABLY SINCE LAST UPDATE.

THE FRONT SHOULD SWEEP ACROSS ALL OF THE REGION THIS EVENING AND
COLD AIR WILL CHANGE ALL REMAIN PRECIPITATION TO SNOW/SNOW SHOWERS.

AREAS WHERE IT RAINS AND RAPID TEMPERATURE FALLS COULD PRODUCE ICY
ROADS/FLASH FREEZING CONDITIONS.

IN NW WHERE IT SNOWS THERE COULD BE SOME BLOWING SNOW.

IT WILL GET WIND BEHIND THE COLD FRONT AND WINDS WILL BECOME QUITE TONIGHT.

VERY COLD OVERNIGHT TOWARD MORNING TEMPERATURES SHOULD FALL TO
AROUND 0 IN NW AND UPPER TEENS IN SOUTHEAST.
-- End Changed Discussion --

&&

.SHORT TERM /THURSDAY/...

-- Changed Discussion --
COLD WINDY START....BUNDLE UP ON WAY OUT IN THE MORNING.

WINDS SHOULD DIMINISH LATE MORNING INTO THE MID AFTERNOON HOURS.
VERY WINDY VERY COLD.

NO SIGNIFICANT PRECIPITATION.

JUST A COLD WINTRY DAY WITH A SHOT AT SOME NEAR RECORD LOW HIGH
TEMPERATURES IF TEMPERATURES DO NOT BEGIN TO RISE BEFORE SUNRISE ON FRIDAY.
-- End Changed Discussion --

&&

.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
THE GOOD NEWS IS THAT THE COLD BLAST WILL BE SHORT-LIVED...WITH A
RAPID MODERATION OCCURRING ON FRIDAY. TEMPS SHOULD EVEN LEVEL OFF
OR GO NON-DIURNAL LATE THU NGT INTO THE PREDAWN HOURS FRI
ESPECIALLY ACRS THE WRN MTNS. SOME OF THE SHELTERED VALLEYS IN THE
ERN PART OF THE CWA MAY STILL DECOUPLE TOWARD DAYBREAK.

BREEZY SW RETURN FLOW IN ADVANCE OF NRN CLIPPER SFC LOW TRACKING
ACRS THE UPPER GREAT LAKES/SRN ONTARIO AND DOWNSLOPING EFFECTS
SHOULD HELP TO BOOST TEMPS INTO THE LOW/MID 40S NORTH AND LOW/MID
50S SOUTH. THE MODELS TURN THE LOW TO THE NORTHEAST UP THE ST.
LAWRENCE VLY ON DAY 5/SAT...DRAGGING A TRAILING/WEAK COLD FRONT
ACRS THE NORTHEAST AND MID-ATL STATES. 12Z MODEL GUIDANCE INDICATES
SOME LGT SHOWER ACTIVITY ALONG THE COLD FRONT...WITH THE HIGHEST
POPS BASED ON CONSENSUS BLEND ACRS NWRN SXNS BTWN 00-06Z SAT

THE LATEST GEFS/EC ENSEMBLE MEANS SHOW THE LARGE SCALE PATTERN
REVERTING BACK TO A WRN RIDGE/ERN TROUGH CONFIGURATION BY EARLY
NEXT WEEK. AT THE SFC...A MODESTLY STRONG/1040MB HIGH PUSHING SEWD
FROM THE UPPER MIDWEST SHOULD DIRECT COLDER AIR INTO THE REGION
BEHIND A REINFORCING FROPA ON SUNDAY...WITH TEMPS TRENDING LOWER
INTO DAY 7/MON. THE 12/12Z GFS NOW COMPARES REASONABLY WELL TO THE
12/00Z ECMWF CONCERNING A SFC WAVE LIFTING NEWD ALONG THE SE COAST
ON MONDAY. THEREFORE INCREASED POPS ACRS SRN AREAS WHICH WOULD BE
ON THE NW EDGE OF THE POTNL PCPN SHIELD ASSOCD WITH THIS LOW. SFC
RIDGE SHOULD MOVE IN FOR TUES WITH ANOTHER WARM-UP POSSIBLE BY 19
MARCH.

&&

.AVIATION /19Z WEDNESDAY THROUGH MONDAY/...
RAIN SHOWERS WILL CONTINUE TO SPREAD EASTWARD ACROSS SRN PA THIS
AFTN...WITH MVFR AND IFR CONDS PREVAILING. A LINE OF HEAVIER
SHOWERS AND EVEN SOME THUNDER RIGHT ALONG THE COLD FRONT AND IS
APPROACHING KJST AT 18Z.

SOME LOW-LEVEL WIND SHEAR IS EXPECTED ABOVE A SHALLOW LAYER OF
COOL AIR THAT IS TRAPPED ACROSS CENTRAL AND EASTERN PA THIS AFTN.

RAIN IS CHANGING OVER TO SNOW ACROSS NW PA /KBFD/ THIS AFTN...AND
THE RAIN/SNOW LINE WILL CONTINUE TO PROGRESS SOUTHEASTWARD AS
COLDER AIR FILTERS INTO THE REGION. VERY GUSTY NORTHWEST WINDS
WILL DEVELOP AS THE COLD AIR IS DRAGGED INTO THE REGION BEHIND
THIS SYSTEM LATE THIS AFTN AND THIS EVENING.

FOR TONIGHT....IFR AND MVFR CONDS SHOULD SLOWLY GIVE WAY TO VFR
ACROSS THE CENTRAL MTNS AND LWR SUSQ VALLEY. REDUCED CIGS MAY
LINGER ACROSS THE WRN HIGHLANDS /KBFD AND KJST/. GUSTY WINDS WILL
CONTINUE TONIGHT INTO THURSDAY.

QUIETER WEATHER SHOULD RETURN FOR FRIDAY.

OUTLOOK...
THU...GUSTY N/NW WINDS...GRADUALLY DIMINISHING IN THE AFTERNOON.
FRI...NO SIG WX EXPECTED.
SAT...WEAK COLD FRONT COULD PRODUCE SCTD -SHRA/-SHSN.
SUN-MON...LOW PRES WILL PASS TO OUR SOUTH AND COULD BRUSH SRN PA
WITH SOME PRECIP.

&&

.HYDROLOGY...
WITH WARMER TEMPERATURES RAINFALL TODAY...WE EXPECT MODERATE
RISES ON RIVERS AND STREAMS. THERE IS STILL ENOUGH ICE IN SPOTS TO
LEAD TO ICE JAMS...THOUGH SIGNIFICANT DECAY HAS OCCURRED AT MANY
LOCATIONS DUE TO THE RECENTLY WARM WEATHER. ANY ICE JAMS WILL BE
ISOLATED IN NATURE. MONITOR WATER LEVELS CLOSELY FOR THE REST OF
THE WEEK.

SOME MINOR FLOODING/PONDING OF WATER IS POSSIBLE IN AREAS WHERE
SNOW AND ICE BLOCK DRAINS AND SLOW RUN OFF.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO NOON EDT THURSDAY
FOR PAZ004>006-010>012-017-018-024-033-037-041-042.
WINTER WEATHER ADVISORY UNTIL 8 AM EDT THURSDAY FOR PAZ017-024-
033.
WIND ADVISORY UNTIL NOON EDT THURSDAY FOR PAZ025>028-034>036-
056>059-063>066.
WINTER WEATHER ADVISORY UNTIL 8 AM EDT THURSDAY FOR PAZ006-010-
011-037.
WINTER STORM WARNING UNTIL 8 AM EDT THURSDAY FOR PAZ004-005.

&&

$$
SYNOPSIS...DANGELO/LA CORTE
NEAR TERM...GRUMM
SHORT TERM...GRUMM
LONG TERM...STEINBUGL
AVIATION...EVANEGO
HYDROLOGY...