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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KCTP 162158
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
558 PM EDT SUN JUN 16 2013

.SYNOPSIS...
A WEAK COLD FRONT WILL CROSS CENTRAL PENNSYLVANIA THIS EVENING.
HIGH PRESSURE WILL VISIT BRIEFLY WHILE THE FRONT STALLS JUST TO
THE SOUTH. 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. TEMPERATURES LOOK
LIKE THEY COULD GET HOT NEXT WEEKEND.

&&

.NEAR TERM /UNTIL 10 PM THIS EVENING/...
MCV OVER WRN PA WAS EASY TO PICK OUT ON THE RADAR LOOPS THIS
AFTN. THAT FEATURE/POTENTIAL FORCING IS NOW MOVING QUICKLY THROUGH
THE CENTRAL COS. COLD FRONT ON THE OTHER HAND IS VERY DIFFICULT TO
MAKE OUT. 19Z POSITION OF THE LOW SEEMS TO BE OVER ERN LO...WITH
COLD FRONT SOUTH OF ERI AND CLE. BUT PRESSURE FIELD NOT VERY
HELPFUL. SHOWERS ALIGNING W-E ACROSS THE NRN TIER ARE FINALLY
DEVELOPING IN THE HEATING AND BETTER MIXING OF THE AFTN. WILL
CONTINUE WITH HIGHER- END POPS FOR THE REST OF THE AFTN...BUT
BRING THEM DOWN AFTER 6 PM...AS THE MCV SHOULD BE THROUGH MOST OF
THE AREA BY THEN...AND MUCH OF THE MOISTURE WILL BE TO THE SOUTH
OF THE FRONT. THE INSTABILITY OF THE DAY WILL ALSO BE GONE AFTER
THEN. THIS THINKING IS IN LINE WITH THE NAM AND IT/S
DEVELOPMENT/DECAY OF SHOWERS IN THE NEAR-TERM.

&&

.SHORT TERM /10 PM THIS EVENING THROUGH 6 PM MONDAY/...
DESPITE A /VERY WEAK/ COLD FRONT SLIDING THROUGH AT THE START OF
THE PERIOD...THERE IS NO SIGNIFICANT DRYING. DEWPOINTS UPSTREAM
WILL STILL BE IN THE L60S. THE LLVL WESTERLY FLOW WILL CREATE A
FLOW WHICH IS USUALLY CONDUCIVE TO LOW CLOUDS - DURING OTHER TIMES
OF THE YEAR. THIS IS A TOUGH FORECAST WITH THE KNOWLEDGE AND
HANDICAP THAT IT IS THE MIDDLE OF JUNE. MOS GUIDANCE DOES DROP BFD
AND JST INTO IFR FOR BRIEF PERIOD LATER TONIGHT. WILL PAINT IN
SOME HIGHER CLOUD COVER FOR THE ALLEGHENIES/LAURELS TONIGHT. WILL
KEEP TEMPS A LITTLE MILDER THAN NORMALS TONIGHT. BUT THE WIND DOES
SEEM TO DROP OFF LATE THIS EVENING AND COULD BUST THE FCST ON THE
COOL SIDE.

THE FRONT STALLS OFF TO OUR SOUTH AND A WEAK IMPULSE OR TWO RIDING
IN FROM THE WEST COULD TOUCH OFF A FEW SHRA IN THE SRN COS...ESP
OVER THE LOWER SUSQ IN THE MORNING. ADDITIONAL ENERGY ROLLING W-E
OFF TO OUR NORTH ON TUESDAY COULD AGAIN HELP TO MAKE ISOLD SHRA IN
THE AFTN ON MONDAY. THE AFTN CAPES ON THE NAM SEEM OVERDONE...AS
DO THE NAM MOS MAX TEMPS IN THE U80S IN THE EAST. WILL TEMPER
THOSE BY A FEW DEGS - KEEPING THEM CLOSE TO THE GFS MOS. THIS
MAKES SENSE WITH 8H TEMPS IN THE MID-TEENS.

&&

.LONG TERM /MONDAY 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.

FRONTAL BOUNDARY PUSHING SOUTH ACROSS CWA MONDAY WILL GET HUNG UP
NEAR THE MASON/DIXON LINE MONDAY NIGHT AS WINDS TURN WESTERLY
/PARALLEL TO FRONT/. SHORTWAVE RIDES IN OVERHEAD...CONTINUING
POPS ACROSS SOUTHERN PORTION OF CWA.

THIS FRONT WILL LIKELY MEANDER BACK NORTHWARD A BIT /INTO
SOUTHERN OR CENTRAL PENN/ FOR TUESDAY AS ANOTHER FAST MOVING
WAVE ALOFT SLIDE EAST ACROSS THE REGION...AND LAPSE RATES
SUPPORT A FEW ROUNDS OF SHOWERS AND THUNDERSTORMS DURING THE DAY.

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 NOTICABLE
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 /22Z SUNDAY THROUGH FRIDAY/...
-- Changed Discussion --
A NEARLY STATIONARY FRONTAL BOUNDARY LIES ACROSS NORTHERN PA THIS
EVENING...WHILE SOUTH OF THE FRONT A MOIST AIR IS FLOWING ACROSS
SOUTHERN PA ON A WESTERLY FLOW. CAN/T RULE OUT AN ISOLD SHRA/TSRA
ACROSS CENTRAL PA THIS EVENING IN VICINITY OF FRONT. HOWEVER...THE
BIGGEST AVIATION CONCERN WILL BE OVERNIGHT AT JST...WHERE THE
PERSISTENT...MOIST WESTERLY FLOW ASCENDING THE ALLEGHENY
HIGHLANDS COULD RESULT IN SOME LOW CIGS. JST REPORTING A 1300 FT
CIG AT 21Z AND ALTHOUGH SATL LOOP SUGGESTS IMPROVEMENT IN THE NEXT
COUPLE HRS...BULK OF LATEST MDL DATA SUPPORTS LOW CIGS DEVELOPING
LATE TONIGHT AS BLYR COOLS.

THE SLOW MOVING FRONT WILL HAVE PASSED JUST SOUTH OF PA ON
MONDAY...KEEPING AN ISOLD SHRA POSSIBLE ACROSS THE FAR SRN TIER
MON MORNING. BUT...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.
WEAK IMPULSES ROLLING THROUGH ON THE WESTERLY FLOW AT THE BASE OF
THE LONG-WAVE TROUGH WILL LEAD TO A HIGHER CHC OF SHOWERS ON
TUESDAY. HOWEVER...MOST OF THE TIME WILL BE VFR. HIGH PRESSURE
FROM CENTRAL CANADA WILL THEN CREATE DRY/FAIR CONDITIONS FOR THE
REST OF THE WEEK.

OUTLOOK...
WED-FRI...NO SIG WX.
-- End Changed Discussion --

&&

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

&&

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