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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KCTP 191352
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
931 AM EDT SUN MAY 19 2013

.SYNOPSIS...
HIGH PRESSURE OVER THE NORTHEASTERN STATES WILL SLIDE OFF THE
COAST TODAY. A PROLONGED STRETCH OF UNSETTLED WEATHER IS IN STORE
OVER THE NEXT SEVERAL DAYS AS A STORM SYSTEM CURRENTLY OVER THE
CENTRAL PLAINS INCHES EASTWARD. TEMPERATURES TODAY WILL GRADUALLY
RISE THROUGH THE FIRST PART OF THE WEEK...BUT WILL COOL BACK BELOW
NORMAL BY NEXT WEEKEND.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
-- Changed Discussion --
STAYING SOMEWHAT IN TUNE WITH MY COLLEAGUES PREVIOUS DESCRIPTION OF
THE THICK CLOUD COVER USING NEIL SEDAKA`S EARLY 1960S /THEN 1975/
POP SONG - BREAKING UP IS HARD TO DO /WITH SUCH A PERSISTENT SERLY
FLOW/...I AGREE WITH HIS ASSESSMENT - WE NEVER CAN SAY GOODBYE.

WE CERTAINLY DON`T WANT TO STRING ANYONE ALONG...WITHOUT ANY RHYME
OR REASON...BY SUGGESTING THAT THE ATMOSPHERE CAN ORCHESTRATE ANY
APPRECIABLE CLEARING ACROSS CENTRAL PA TODAY. IN FACT...DEEP LAYER
MOISTURE WILL CONTINUE TO INCREASE ACROSS THE COMMONWEALTH INTO
TONIGHT WITH THE NOSE OF A NORTH/SOUTH AXIS OF ANOMALOUSLY HIGH PWAT
AIR /1.5-1.75 INCHES/ MOVING INTO THE REGION...LOCKING IN THE THICK
CLOUD COVER.

PORTIONS OF THE NW MTNS HAVE ALREADY BROKEN OUT INTO SOME CLEARING
AND WILL CONTINUE TO SEE PERIODS OF - SUNSHINE ON MY SHOULDERS -
THROUGH THIS AFTERNOON...SINCE THE DEPTH OF THE MOISTURE IS THE MOST
SHALLOW THERE...AND LLVL DOWNSLOPING TO THE WEST OF THE SPINE OF THE
APPALACHIANS WILL OCCUR.

THE BASE OF THE THICK STRATUS/STRATOCU DECK WILL BE DRAPED OVER THE
RIDGE TOPS INTO THE MIDDAY HOURS. THE STRONG MAY SUN COULD LIFT THE
BASE OF THE DECK UP A LITTLE...BUT HOLES IN THE CLOUDS WILL BE TOUGH
TO FIND. THE CLOUDS ARE MADE OF MARITIME AIR WHICH CONTAINS LOTS OF
FINE DROPLETS WHICH ARE ALWAYS GOOD FOR PRODUCING AREAS OF LIGHT
DRIZZLE. FORCING IS ALMOST NON EXISTENT ABOVE THE LOWEST 5KFT OF THE
ATMOSPHERE TODAY. THE CLOUDS WILL AGAIN KEEP TEMPS DOWN BELOW
NORMALS ACROSS MOST OF THE AREA. JUST THOSE LUCKY FEW PLACES IN THE
WEST COULD MEET OR EXCEED CLIMO HIGHS.
-- End Changed Discussion --

&&

.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/...
A MINOR UPPER RIDGE IS GENERALLY IN PLACE FROM THE UPPER GREAT
LAKES TO THE GULF COAST. HOWEVER...THE OLD MID-LEVEL LOW IS STILL
SEEN IN MDL INITIALIZATIONS OVER THE OHIO VALLEY. THIS FEATURE AND
THE DEAD/DIFFUSE FRONT TO OUR SOUTH WILL CONTINUE TO GENERATE
SHOWERS ALL ACROSS THE MID-ATLANTIC FOR THE NEXT TWO DAYS UNTIL
THE LOW FINALLY DISAPPEARS SOMETIME AROUND MONDAY NIGHT AS IT
PASSES OVERHEAD. UPSTREAM CONVECTION WILL BE DROPPING ACROSS THE
GREAT LAKES AND WILL ONLY PROLONG THE CLOUDY/SHOWERY FORECAST FOR
LATE THIS PERIOD.

ON TUESDAY...WE SHOULD ENTER THE WARM SECTOR AHEAD OF THE STORM
LANGUISHING OVER THE PLAINS/MIDWEST/UPPER LAKES. THE WARM SECTOR
AIR WILL BE QUITE WARM FOR THE TIME OF YEAR...HAVING SPENT PLENTY
OF TIME COOKING OVER THE MS AND OH VALLEYS WITH GOOD GULF INFLOW.
TEMPS THERE RIGHT NOW ARE ABOUT 10F ABOVE AVERAGES. THEREFORE...THE
TEMPS SHOULD ROUND OUT TO 80F OR BETTER IN MANY LOCATIONS TUES.
BUT SCT AFTN CONVECTION IS THEN POSSIBLE.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
THE MEDIUM RANGE GUIDANCE CONTINUES TO ADVERTISE A RATHER
UNSETTLED PERIOD OF TIME FOR MUCH OF THE UPCOMING WEEK.

WE ARE AND WILL REMAIN BASICALLY UNDER A MEAN UPPER RIDGE...BUT
THE PROBLEM WILL BE A WEAK FRONTAL SYSTEM THAT WILL BE MEANDERING
AROUND CENTRAL PA FOR MUCH OF THE TIME INTO LATE WEEK. SO WHILE
THERE IS SUPPORT ALOFT FOR ORGANIZED PRECIP...THE SHOWERS WILL BE
TIED TO SMALL SCALE FEATURES THAT WILL BE HARD TO SEE MORE THAN A
DAY OR TWO DOWN THE ROAD. THE LOW LEVEL FORCING AND INCREASING
HUMIDITY/INSTABILITY WILL BRING SEVERAL CHANCES FOR MAINLY DIURNAL
SHOWERS AND THUNDERSTORMS.

THE FORECAST HAS A LOT OF REDUNDANCY IN IT...IMPLYING A PROLONGED
PERIOD OF RAIN/STORMS. THE REALITY IS LIKELY TO BE MORE LIKE A
PERIOD OF MAINLY CLOUDY SKIES BUT WITH SUNNY BREAKS DURING THE
DAY...ALONG WITH SHOWERS THAT WILL BE MOST LIKELY IN THE AFTERNOON
AND EVENING. A DIFFUSE FRONT WILL ATTEMPT TO PUSH NORTHWARD DURING
THE MIDDLE OF THE WEEK. WHERE THE FRONT WILL BE ON ANY GIVEN DAY
WILL HAVE MUCH TO DO WITH MESOSCALE INFLUENCES FROM ANY CONVECTION
THAT MANAGES TO FORM.

DESPITE AMPLE CLOUD COVER AND THE CHANCES FOR RAIN...TEMPERATURES
SHOULD REMAIN ABOVE NORMAL UNTIL AT LEAST LATE WEEK WHEN GUIDANCE
SUGGESTS WE FINALLY SEE A COLD FRONT MOVE THROUGH USHERING IN
MUCH COOLER AIR AND DRIER CONDITIONS.

&&

.AVIATION /13Z SUNDAY THROUGH THURSDAY/...
-- Changed Discussion --
A WAVY FRONTAL BOUNDARY JUST TO OUR SOUTH WILL SLOWLY RETURN
NORTHWARD ACROSS PENNSYLVANIA AS A WARM FRONT LATE TODAY INTO MONDAY.

WIDESPREAD IFR /TO VERY LOW END MVFR CIGS/ WILL CONTINUE THROUGH AT
LEAST 17Z TODAY BEFORE LIFTING TO LOW-MID RANGE MVFR DURING THE MID
TO LATE AFTERNOON HOURS THANKS TO SEVERAL DEG F OF BOUNDARY LAYER
WARMING.

RIDGE TOPS AOA APPROX 1900 FT MSL WILL CONTINUE TO BE SHROUDED IN
THE LOW CLOUDS/FOG THROUGH AT LEAST EARLY THIS AFTERNOON.

AREAS OF DRIZZLE AND SOME SHRA WILL BE MOVING BACK TOWARD PA FROM
THE SOUTH THIS AFTERNOON AS WELL. THE HIGHEST PROBABILITY FOR THE
LIGHT QPF WILL BE ACROSS THE SOUTHERN PA TAF AIRFIELDS
/KJST/LNS/MDT/CXY.

AFTER SOME MINOR...BRIEF IMPROVEMENT TO CIGS AND VSBYS THIS
AFTERNOON...WIDESPREAD IFR RETURNS FOR LATER THIS EVE INTO MONDAY AS
THE AFOREMENTIONED WARM FRONTAL BOUNDARY LIFTS SLOWLY NORTHWARD.

A RATHER UNSETTLED AND POTENTIALLY WET PATTERN IS EXPECTED DURING
THE MIDDLE TO SECOND HALF OF UPCOMING WEEK...WITH DAILY CHC/S FOR
CONVECTIVE PCPN AND ASSOCD RESTRICTIONS.

.OUTLOOK...
MON...MVFR-IFR CIGS.
TUE-THU...VFR-MVFR WITH SCT PM THUNDERSTORM IMPACTS.
-- End Changed Discussion --

&&

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

&&

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