AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
505 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/...
THE STRATUS IS HERE. BREAKING UP IS HARD TO DO...WITH SUCH A
PERSISTENT SERLY FLOW. IF ANYWHERE CAN BREAK OUT - IT WILL BE THE
EXTREME WRN PART OF THE AREA WHERE MIXING COULD OCCUR...PULLING A
LITTLE OF THE /DOWNSLOPE/ CLEARING OVER THE WRN PART OF THE STATE
EASTWARD INTO THE CWA. THE CLOUDS HAVE LOWERED AND WILL BE DRAPED
OVER THE RIDGES THROUGH MOST OF THE MORNING. 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
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.
&&
.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 /09Z SUNDAY THROUGH THURSDAY/...
A WAVY FRONTAL BOUNDARY WILL REMAIN TO OUR SOUTH THROUGH THE TAF
PERIOD...BEFORE SLOWLY RETURNING NORTHWARD AS A WARM FRONT LATE
SUNDAY INTO MONDAY.
WIDESPREAD IFR CIGS WILL CONTINUE OVERNIGHT AS LIGHT TO MDT SERLY
FLOW BECOMES FIRMLY ENTRENCHED OVER CENTRAL PA. EXPANDING AREAS OF
FOG AND LOWERING VSBYS WILL ONLY ADD TO THE ALREADY LOWERED CONDS.
LIGHT PCPN...MAINLY AREAS OF DRIZZLE AND SOME SHRA MOVING BACK
TOWARD PA AS WELL. HIGHEST PROBABILITY FOR THE LIGHT QPF WILL BE
ACROSS THE SOUTHEASTERN TAF AIRFIELDS LNS/MDT/CXY BETWEEN 06-12Z.
LOW CIGS WILL PERSIST THROUGH THE DAYLIGHT HOURS TODAY...WITH
SOME IMPROVEMENT TO MVFR LIKELY THIS AFTERNOON...BEFORE
WIDESPREAD IFR RETURNS FOR LATER THIS EVE INTO MONDAY AS A
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.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DANGELO
NEAR TERM...DANGELO
SHORT TERM...DANGELO
LONG TERM...LA CORTE/STEINBUGL
AVIATION...GARTNER/RXR
