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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KCTP 281907
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
207 PM EST SAT FEB 28 2015

.SYNOPSIS...
HIGH PRESSURE OVER PENNSYLVANIA WILL PASS OFF THE NEW ENGLAND
COAST THIS EVENING. LOW PRESSURE TRACKING UP THE OHIO VALLEY
SUNDAY WILL CROSS PENNSYLVANIA SATURDAY NIGHT...BRINGING SNOW AND
MIXED PRECIPITATION TO CENTRAL PA THROUGH EARLY MONDAY MORNING.
A STRONGER AREA OF LOW PRESSURE WILL LIKELY TRACK WEST OF
PENNSYLVANIA LATE TUESDAY AND EARLY WEDNESDAY.

&&

.NEAR TERM /UNTIL 8 PM THIS EVENING/...
TEMPS HAVE REBOUNDED NICELY UNDER SUNNY SKIES AFTER A FRIGID
EARLY MORNING UNDER THE 1044 MB RIDGE. EARLY AFTERNOON READINGS
RANGE FROM MID TEENS NORTH TO AROUND 20 SOUTHEAST.

FAIR AND STILL COLD CONDITIONS EXPECTED THROUGH THIS EVENING AS
SFC HIGH DRIFTS OVR THE REGION. REGIONAL IR LOOP INDICATES MID
LEVEL CLOUDS ASSOCIATED WITH AN UPPER SHORTWAVE OVER INDIANA AND
OHIO...WHICH WILL TRACK INTO THE WEST CENTRAL MOUNTAINS AND LAUREL
HIGHLANDS MID TO LATE AFTERNOON. ONLY IMPACT WILL BE TO DIM THE
BRIGHT SUNSHINE LATE THIS AFTERNOON...AS HIGHS REACH 20-25 IN MOST
AREAS.

&&

.SHORT TERM /8 PM THIS EVENING THROUGH SUNDAY NIGHT/...
UPCOMING PRECIP WILL EXTEND BETWEEN A 12-24 HOUR EVENT...
MEANING THAT 24 HOUR WATCH/WARNING CRITERIA MUST BE USED TO
VERIFY AMOUNTS. HERE IN CENTRAL PA...THAT MEANS A MID POINT OF 8"
MUST ACCUMULATE IN 24 HOURS FOR WARNING CRITERIA TO BE MET...AND
THE OVERWHELMING CONSENSUS AFTER LOOKING AT MORNING DATA SUITE IS
THAT WE WON`T SEE THAT EXCEPT FOR SPOT AMOUNTS ACROSS THE
NORTHWEST OR WEST CENTRAL MOUNTAINS WHERE WATCHES WERE IN EFFECT.

COLLAB WITH ALL SURROUNDING OFFICES HAS PROMPTED ADVISORY
ISSUANCES FOR ALL OF MY COUNTIES. ACROSS THE NORTHWEST...A GENERAL
6 TO 8 INCHES IS EXPECTED...WHILE ELSEWHERE 2 TO 4 INCHES AND A
COATING OF ICE WILL BE COMMON. FOR THE FAR SOUTH AND SOUTHEAST...
A COATING TO LESS THAN TWO INCHES OF SNOW IS EXPECTED TO BE
FOLLOWED BY ONE TO TWO TENTHS OF AN INCH OF FREEZING RAIN. LITTLE
IN THE WAY OF WIND MEANS THIS SHOULD NOT BE A PARTICULARLY
DAMAGING OR DISRUPTIVE EVENT (IN TERMS OF POWER, ETC).

BLEND OF MORNING MDL OUTPUT BRINGS LIGHT SNOW INTO THE WEST
CENTRAL MOUNTAINS BEFORE DAWN SUNDAY. FOR THE REST OF CENTRAL
PA...LGT SNOW IS LIKELY TO ARRIVE BY LATE AM.

AGREE WITH PREVIOUS THINKING THAT HEAVIEST PRECIP WILL LIKELY
HOLD OFF UNTIL STRONGER FORCING ARRIVES WITH APPROACH OF N STREAM
SHORTWAVE DIVING ACROSS THE GRT LKS SUNDAY PM. ASSOC LL JET AND
SURGE OF WARMER AIR ALOFT WILL LKLY CHANGE LGT SNOW TO A WINTRY
MIX ACROSS SOUTHERN PA LATE SUNDAY AND SUNDAY EVENING...WHILE MDL
SOUNDINGS AND ENSEMBLE PTYPE PLUMES INDICATE ALL SNOW ACROSS AREAS
NORTH OF I-80.

THE TRANSITION TO FREEZING RAIN SHOULD TAKE PLACE FROM LATE
AFTERNOON THROUGH LATE EVENING SUNDAY ACROSS THE SOUTHERN HALF OF
MY CWA. PRECIP LOOKS TO TAPER OFF IN ALL AREAS DURING THE PRE DAWN
HOURS MONDAY MORNING.

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...

-- Changed Discussion --
BLUSTERY AND COLDER CONDITIONS WILL MAKE A RETURN ON MONDAY AS
SYSTEM NUMBER ONE SLIDES OFF TO OUR EAST. OTHER THAN THE USUAL
POST FRONTAL SNOWS SHOWERS...FAVORING WESTERN HIGHER
ELEVATIONS...CONDITIONS WILL BE IMPROVING OVERALL.

HIGH PRESSURE WILL BE SHORTLIVED MONDAY NIGHT INTO TUESDAY WHEN
THE NEXT IN THE SERIES OF STORM SYSTEMS IS SLATED TO ENTER THE
LOCAL WEATHER SCENE. THIS ONE PROMISES MORE OF A MESSY OUTCOME AS
IT SHOULD TRACK WELL TO OUR NW...MEANING WARM AIR EVENTUALLY
INVADING THE REGION...WITH A SNOW TO SLEET/FREEZING RAIN AND EVEN
RAIN SCENARIO.

SNOW AMOUNTS DO NOT LOOK TO BE THE BIGGEST PART OF THE MIDWEEK
STORM AS WE ARE PROGGED TO WARM ALOFT RATHER QUICKLY. WITH A DEEP
SNOW PACK AND A LOT OF COLD AIR TO DISPLACE...WE WILL LIKELY SEE
A PERIOD OF ICING BEFORE WARM AIR EVENTUALLY CHANGES EVERYTHING TO
RAIN TUESDAY NIGHT INTO WEDNESDAY.

RAIN SHOULD TAPER OFF TO SCATTERED SHOWERS WITH THE PASSAGE OF
THE TRAILING COLD FRONT EARLY WEDNESDAY.

EARLIER MODEL RUNS SUGGESTED LATER WEDNESDAY INTO THURSDAY THERE
COULD BE A RETURN OF SNOW TO SRN PA ASSOCIATED WITH A FLAT SRN
STREAM WAVE...BUT LATEST OPERATIONAL ECMWF/GFS NOW KEEP THE
SURFACE WAVE SUPPRESSED MAINLY SOUTH OF THE REGION..HINTING THAT
ONLY FAR SERN AREAS WILL BE AT RISK FOR A PERIOD OF OVER RUNNING
SNOW. THE 06Z GEFS IS A LITTLE MORE GENEROUS WITH THE POPS SO IT`S
NOT OUT OF THE QUESTION THAT SOMETHING WILL YET HAPPEN AS MODELS
TRY AND RESOLVE SMALL SCALE FEATURES DROPPING OUT OF CENTRAL
CANADA INTO THE EASTERN US LONG WAVE. TOO FAR OFF TO LEAN ONE WAY
OR ANOTHER FOR A SOLUTION.

BEHIND THE MID WEEK SYSTEM...ANOTHER PUSH OF ARCTIC AIR WILL
BRING TEMPS AND POPS BACK WELL BELOW NORMAL FOR LATE THURSDAY INTO
FRIDAY. THE ONLY GOOD THING SEEMS TO BE EACH ARCTIC SHOT IS A
LITTLE LESS POTENT THAN THE LAST AS WE LEAVE THE RECORD COLD OF
FEBRUARY BEHIND.
-- End Changed Discussion --

&&

.AVIATION /19Z SATURDAY THROUGH THURSDAY/...
SURFACE HIGH PRESSURE WILL DRIFT SLOWLY EAST THROUGH TONIGHT.
CONDITIONS WILL REMAIN VFR INTO TONIGHT...WITH LITTLE MORE THAN
SOME HIGH CLOUDINESS PASSING OVERHEAD DURING THE DAY BEFORE MID
DECK THICKENS THIS EVENING. WINDS WILL BE LIGHT THROUGH THIS
PERIOD.

CONDITIONS WILL BEGIN TO DETERIORATE LATE TONIGHT INTO
SUNDAY...AS A WAVE OF LOW PRESSURE SLIDES FROM OKLAHOMA THROUGH
THE MIDWEST AND INTO PA AT THE SAME TIME THE NORTHERN STREAM
TROUGH BEGINS TO DIG. AN EXPANDING AREA OF WAA TYPE SNOWFALL WILL
SPREAD IN FROM THE OHIO VALLEY STARTING AROUND 09Z. AT THE SAME
TIME...CLOUDS WILL THICKEN AND LOWER WITH WIDESPREAD RESTRICTIONS
DEVELOPING FROM W TO E. THE SNOW IS EXPECTED TO CHANGE TO A WINTRY
MIX ACROSS SRN PA LATER SUNDAY.

CONDITIONS SHOULD BEGIN TO IMPROVE ON MONDAY AND REMAIN GOOD INTO
EARLY TUESDAY...BEFORE THE NEXT SYSTEM PUSHES ANOTHER ROUND OF
PRECIP AND REDUCED FLYING CONDS INTO THE AREA.

OUTLOOK...

TONIGHT...SNOW OVERSPREADING THE AREA FROM W TO E AFTER MIDNIGHT.
RESTRICTIONS DEVELOPING FROM W TO E.

SUN...WIDESPREAD RESTRICTIONS. PRECIP SHOULD REMAIN ALL SNOW
ACROSS NRN PA...WHILE MIXING W/ SLEET AND FREEZING RAIN ACROSS THE
SOUTH.

MON...CONTINUED CIG/VIS REDUCTIONS POSSIBLE...MAINLY AM.

TUE...VFR AM. MIXED PRECIP WITH CIG/VIS REDUCTIONS POSSIBLE LATE.

TUE NIGHT-WED...CIG/VIS REDUCTIONS CONTINUE IN WINTRY MIX/RAIN.

&&

.CLIMATE...

-- Changed Discussion --
THE COLDEST FEBRUARY ON RECORD IS STILL LOOKING LIKELY.

MONTHLY MEAN TEMPERATURES THROUGH THE 27TH...IPT 18.2...MDT 20.9.

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.
-- End Changed Discussion --

&&



.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 7 AM SUNDAY TO 7 AM EST MONDAY
FOR PAZ006-012-018-019-024>028-033>037-041-042-045-046-049>053-
056>059-063>066.
WINTER WEATHER ADVISORY FROM 4 AM SUNDAY TO 7 AM EST MONDAY
FOR PAZ004-005-010-011-017.

&&

$$
SYNOPSIS...DEVOIR
NEAR TERM...DEVOIR
SHORT TERM...DEVOIR
LONG TERM...LA CORTE
AVIATION...DEVOIR/RXR
CLIMATE...LA CORTE