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000
FXUS61 KCTP 170920
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
520 AM EDT MON JUN 17 2013

.SYNOPSIS...
A SERIES OF WEAK SURFACE FRONTS WILL CROSS THE COMMONWEALTH TODAY
AND TONIGHT...BRINGING ISOLATED TO SCATTERED SHOWERS AND A SLIGHT
CHANCE OF AFTERNOON THUNDERSTORMS TO CENTRAL PENNSYLVANIA. MOST
AREAS WILL BE DRY MOST OF THE TIME...DESPITE THE CHANCE FOR
PRECIPITATION TODAY INTO THIS EVENING. ANOTHER WAVE OF LOW PRESSURE
WILL ROLL EAST THROUGH THE APPALACHIANS ON TUESDAY. GENERALLY DRY
WEATHER WILL FOLLOW FOR THE SECOND HALF OF THE WEEK AS A LARGE
AREA OF HIGH PRESSURE BUILDS INTO THE REGION FROM THE UPPER
MIDWEST. ABOVE NORMAL TEMPERATURES WITH INCREASING HUMIDITY ARE
EXPECTED FOR NEXT WEEKEND AS THE RIDGE AMPLIFIES AND COVERS MOST
OF THE EASTERN HALF OF THE COUNTRY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
RUC13 850 MB THETA E FIELD DEPICTS SLOWLY SOUTHWARD SINKING FRONTAL
BOUNDARY OVER THE CENTRAL MOUNTAINS THIS MORNING. ISOLATED SHOWERS AND
THUNDERSTORMS CONTINUE TO FIRE IN THE WARM SECTOR AHEAD OF THE
BOUNDARY OVER THE LAUREL HIGHLANDS. EARLIER ACTIVITY ACROSS THE
CENTRAL AND NORTHERN MOUNTAINS HAS DISSIPATED AS THE BOUNDARY HAS
SETTLED SOUTHWARD...BUT PRODUCED BRIEF DOWNPOURS IN THE POST-
MIDNIGHT HOURS THAT DROPPED UP TO 0.10" IN LESS THAN 5 MINUTES
HERE AT THE OFFICE.

BOUNDARY SHUD CONTINUE TO SINK SOUTHWARD THIS MORNING...KEEPING
ISOLATED TO SCATTERED SHOWERS OVER THE SOUTHERN THIRD OF CENTRAL
PA THIS MORNING. ANOTHER UPSTREAM FRONT LOCATED OVER THE EASTERN
GLAKS THIS MORNING WILL DROP INTO THE NORTHWEST MOUNTAINS AND
NORTHERN TIER BY LATE THIS MORNING...INCREASING POPS FOR AFTERNOON
AND EVENING SHOWERS AND ISOLATED THUNDERSTORMS. AREAL COVERAGE
PROBABILY WON`T EXCEED 30 PERCENT AT ANY GIVEN TIME THIS AFTERNOON
AND EVENING...AND MOST AREAS WILL BE DRY MOST OF THE TIME.

HIGHS THIS AFTERNOON WILL RANGE FROM THE UPPER 70S NORTHWEST TO
THE MID TO UPPER 80S FROM THE SOUTH CENTRAL MOUNTAINS TO THE LOWER
TO MIDDLE SUSQ RIVER VALLEY. DEWPOINTS IN THE MID 50S TO LOWER 60S
WILL SLIGHTLY LOWER...BUT WITH LESS OF A BREEZE AND A LITTLE MORE
SUNSHINE IT WILL FEEL A BIT MORE UNCOMFORTABLE.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
THE FRONTAL BOUNDARY PUSHING SOUTH ACROSS THE CWA THIS AFTERNOON WILL
STALL NEAR THE MASON/DIXON TONIGHT WHILE 5H TROF ARRIVES OVERHEAD...
CONTINUING POPS ACROSS SOUTHERN PORTION OF CWA. THIS BOUNDARY MAY
CONTINUE TO BE A FOCUS FOR CONVECTION ON TUESDAY AS IT MEANDERS
NORTHWARD AGAIN...AND DEEPER LAYER MOISTURE WITH WIDESPREAD PW
GREATER THAN 1.0" RETURNS TO CENTRAL PA. SO WILL CONTINUE TO CARRY
SLC TO CHC POPS FOR A FEW ROUNDS OF CONVECTION AGAIN ON TUESDAY.

TUESDAY MAXES WILL BE A FEW DEGREES COOLER THROUGHOUT... RANGING
FROM THE LOWER 70S NORTH TO THE LOWER 80S SOUTHEAST.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
BROAD TROUGH OVER NORTHEAST U.S. WILL BRING AN UNSETTLED START TO
THE WEEK...BUT RIDGE BUILDING IN STARTING MIDWEEK WILL BRING DRY
AND COOLER WEATHER BEFORE MORE HUMID AND SHOWERY CONDITIONS RETURN
FOR THE WEEKEND.

NORTHERLY FLOW DEVELOPS TUE NIGHT INTO WED AS HIGH PRESSURE
BUILDS SOUTHWARD ACROSS GLAKES...WHICH WILL KICK THE FRONTAL
BOUNDARY FURTHER SOUTH AND USHER IN BEGINNING OF A PERIOD OF DRIER
AND COOLER WEATHER.

WE/LL SEE A FEW CHILLIER NIGHTS...ESP ACROSS THE NORTH /THE
COLDEST BEING WED NIGHT WITH READINGS DIPPING INTO THE 40S NORTH
OF I-80/ AS HIGH SETTLES IN. BUT SOUTHWESTERLY RETURN FLOW BEGINS
ON THU AS RIDGE AXIS DRIFTS TO OUR EAST. AS LOWER LEVELS BEGIN TO
SLOWLY MOISTEN BACK UP...ISOLATED LATE DAY TSTMS AGAIN BECOME
POSSIBLE OVER SOUTHERN HALF THU AND ESP FRI.

HEIGHTS RISE HEADING INTO THE WEEKEND. SURGE OF MOISTURE ALSO GETS
SHUNTED EASTWARD FROM THE CENTRAL U.S. BRINGING A NOTICEABLE
INCREASE IN THE HEAT AND ESPECIALLY HUMIDITY. TSTM PROBABILITIES
INCREASE SAT...PEAKING ON SUNDAY BEFORE A COLD FRONT DROPS ACROSS
THE GLAKES EARLY NEXT WEEK BRINGING A GRADUAL CHANGE IN AIRMASS
BACK TOWARD DRIER CONDITIONS.

&&

.AVIATION /09Z MONDAY THROUGH FRIDAY/...
ISOLATED SHOWERS AND THUNDERSTORMS ARE WAINING AS WE REACH THE
MIDPOINT OF THE OVERNIGHT PERIOD. EXPECT AN SHOWERS TO FADE AND
DISPERSE AS THE EVENING CONTINUES. THE BIGGEST AVIATION CONCERN
WILL BE THE W MTNS...WHERE THE PERSISTENT...MOIST WESTERLY FLOW
ASCENDING THE ALLEGHENY HIGHLANDS WILL RESULT IN SOME LOW
CIGS...ESP AT JST...AND AT TIMES BFD. JST REPORTING A 900 FT CIG
AT 06Z AND BULK OF LATEST MDL DATA SUPPORTS IFR CIGS CONTINUING
THROUGH 12Z AT JST AS BLYR COOLS/MOISTENS.

THE SLOW MOVING FRONT WILL PASS JUST SOUTH OF PA TODAY...KEEPING
AN ISOLD SHRA POSSIBLE ACROSS THE FAR SRN TIER THIS MORNING.
MUCH OF THE AREA WILL REMAIN DRY. WILL NOT MENTION ANY PRECIP FOR
ANY TERMINALS FOR 12-18Z MONDAY...BUT MDT/LNS COULD PICK UP A
SHOWER DURING THE EARLY MORNING HOURS. MDL SOUNDINGS INDICATE ANY
EARLY LOW CLOUDS ACROSS THE W MTNS WILL MIX OUT TO MSUNNY SKIES
BTWN 12Z-15Z.

OUTLOOK...
TUE...PATCHY FOG POSSIBLE EARLY AM. PM TSRA IMPACTS POSS SOUTH.
WED-FRI...NO SIG WX EXPECTED.

&&

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

&&

$$
SYNOPSIS...DANGELO/DEVOIR
NEAR TERM...DEVOIR
SHORT TERM...DEVOIR
LONG TERM...DEVOIR/RXR
AVIATION...FITZGERALD/CERU