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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KCTP 180556
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
156 AM EDT SAT MAY 18 2013

.SYNOPSIS...
A WAVY FRONTAL BOUNDARY EXTENDING FROM THE UPPER MIDWEST THROUGH
THE OHIO VALLEY AND ACROSS THE CENTRAL APPALACHIANS INTO SOUTHERN
MID-ATLANTIC STATES WILL SLOWLY RETURN NORTHWARD AS A WARM FRONT
THROUGH MONDAY. THE WARM FRONT WILL THEN STALL OUT ACROSS UPSTATE
NEW YORK AND NEW ENGLAND BEFORE SINKING BACK TO THE SOUTH AND
OSCILLATING OVER PENNSYLVANIA INTO THE MIDDLE OF NEXT WEEK. THE
FRONT SHOULD FINALLY PUSH SOUTH OF THE AREA BY LATE NEXT WEEK OR
EARLY IN THE WEEKEND...AS A LARGE CANADIAN HIGH PRESSURE SYSTEM
DROPS SOUTHEAST INTO THE GREAT LAKES REGION. OVERALL EXPECT A
PROLONGED STRETCH OF UNSETTLED WEATHER OVER THE NEXT SEVERAL DAYS.

&&

.NEAR TERM /UNTIL 9 AM THIS MORNING/...
-- Changed Discussion --
JET STREAK WHICH IS PRETTY FAR TO OUR NE APPEARS TO BE AIDING LIFT
OVER NWRN PA...AND GENERATING THICK MID DECK. DECK THICK ENOUGH
THAT IT IS PRODUCING A FEW SPRINKLES AS EVIDENCED BY RADAR AND
UPSTREAM OBS FROM ACROSS THE POND. THERE IS ALSO A DEVELOPING MID
DECK OVER THE SERN COS...AND THE EVENTUAL AIDED LIFT COULD MAKE A
SPRINKLE THERE AS WELL. WILL KEEP POPS BELOW 20 PCT DUE TO THE DRY
AIR BELOW THE CLOUDS AND COUNT ON SOME/ALL OF THE PRECIP TO
EVAPORATE BEFORE HITTING THE GROUND.
-- End Changed Discussion --

&&

.SHORT TERM /9 AM THIS MORNING THROUGH 6 AM SUNDAY/...
-- Changed Discussion --
THE DEGREE OF INFLUENCE THE FILLING UPPER LOW COMING OUT OF THE
PLAINS WILL HAVE IS A TOUGH CALL. HOWEVER...GENERAL MDL PREFERENCE
IS TO KEEP THE BULK OF THE SHRA S OF THE STATE. THE GENERAL FLOW
PATTERN DOES BECOME MORE SERLY DURING THE DAY ON SAT. THE MID/HIGH
CLOUDS COULD KEEP MAXES DOWN IN THE L70S FOR MOST AREAS.
HOWEVER...HEATING SHOULD BE SUFFICIENT TO POP A FEW CU...MAINLY
OVER THE HIGHER ELEVATIONS. THE MOISTURE FROM THE ATLANTIC OCEAN
WILL START TO BE DRAWN NORTHWARD ALONG THE APPALACHIANS AND WILL
START TO BUILD UP LATER SAT AFTN AND EXPAND OVER ALMOST THE ENTIRE
AREA SAT NIGHT. THIS SHOULD KEEP MINS MILD. WILL ALSO MAKE A LOW
CHC FOR SOME LIGHT RAIN AS THE MARITIME MSTR CLIMBS UPHILL...WITH
HIGHER 30-40 POPS S AND SLIGHT CHC N.
-- End Changed Discussion --

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
-- Changed Discussion --
A SE FLOW WILL KEEP THE RISK OF LOWER CLDS AND A FEW SHOWERS
ACROSS THE REGION FOR SUNDAY AND SUNDAY NIGHT.

LESS CHC OF SHOWERS MONDAY INTO TUE...AS THE WINDS SHIFT MORE
TO THE SW...AS THE WARM FRONT LIFTS NORTH OF THE AREA.

WARMER TEMPS WILL BE ACROSS THE AREA TUE INTO WED.

HPC HAS FRONT SAGGING SOUTHWARD ON WED...NOT ALL THAT CLEAR CUT.
FOR WED...DID UP POPS SOME...BUT LEFT TEMPS UP.

COMPLEX SITUATION FOR LATE NEXT WEEK...AS WE HEAD INTO THE
HOLIDAY WEEKEND. A LOT OF SPREAD IN MODEL SOLUTIONS THE LAST
FEW DAYS.

FOR NOW...DID NOT RUSH CLEARING TOO MUCH BEFORE NEXT FRIDAY.
EXPECT SOME SHOWERS AND THUNDERSTORMS INTO THU NIGHT...AS THE
COLD FRONT MOVES SOUTHWARD...AND LOW TRIES TO CLOSE OFF. GUSTY
NE WINDS WILL BE POSSIBLE...ALONG WITH MUCH COOLER TEMPS BY
FRIDAY...AS THE SOURCE REGION OF THE AIR WILL BE CENTRAL
CANADA...AS WAS THE CASE EARLIER THIS WEEK. A LOT DIFFERENT
THAN LAST YEAR...WHEN WE HAD HOT TEMPERATURES AND EVEN SOME
STRONG STORMS.
-- End Changed Discussion --

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
18/06Z...
VFR FLYING WILL CONTINUE WITH SCT-BKN ALTO CU BASES AROUND 10KFT
AGL. THE LOW-LEVEL FLOW WILL VEER TO THE SE THIS AFTN AND DIRECT
INCREASINGLY MOIST/MARITIME AIR INTO THE REGION. THIS WILL RESULT
IN WIDESPREAD MVFR TO IFR CIGS WITH MODERATE TO HIGH CONFIDENCE
FROM TONIGHT THROUGH MONDAY. A STATIONARY FRONTAL BOUNDARY WILL
LIFT SLOWLY NORTHWARD ACROSS THE AIRSPACE BY TUESDAY...WHICH
SHOULD ALLOW FOR SOME MARGINAL IMPROVEMENT IN LCL FLYING CONDS.

.OUTLOOK...

SUN-MON...MVFR-IFR CIGS.
TUE- WED...VFR-MVFR WITH SCT PM THUNDERSTORM IMPACTS.

&&

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

&&

$$
SYNOPSIS...LA CORTE
NEAR TERM...DANGELO
SHORT TERM...DANGELO/GARTNER
LONG TERM...MARTIN
AVIATION...STEINBUGL