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000
FXUS61 KCTP 170316
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1116 PM EDT SUN JUN 16 2013

.SYNOPSIS...
A WEAK COLD FRONT WILL SLIDE SLOWLY SOUTHEAST ACROSS CENTRAL
PENNSYLVANIA TONIGHT. HIGH PRESSURE WILL VISIT BRIEFLY ON MONDAY
WHILE THE FRONT STALLS JUST TO THE SOUTH OF THE REGION. 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 7 AM MONDAY MORNING/...
SFC COLD FRONT EXTENDED FROM NEAR KBGM WSW TO KFKL AT 02Z. THIS
BOUNDARY HAS BECOME NEARLY STATIONARY AS A RESULT OF BACKING LLVL
FLOW AND INCREASING UVVEL BENEATH THE RIGHT ENTRANCE REGION OF A
95KT UPPER LEVEL JET /THAT STRETCHED FROM NWRN PENN TO NRN NEW
ENGLAND/.

A BAND OF SHOWERS AND A FEW TSRA IS SLIDING EAST ALONG THIS BOUNDARY
WITHIN A RIBBON OF RATHER HIGH...ML CAPE EXCEEDING 1500 J/KG. LATEST
4 AND 12KM NAM 3 HRLY PRECIP FITS NICELY WITHIN THE EAST/WEST AXIS
OF FCST ML MOST UNSTABLE CAPE /OVER 1200 J/KG/ THROUGH 07Z MONDAY.
THIS AREA OF ENHANCED INSTABILITY AND LLVL THETA-E CONVERGENCE WILL
BE FOCUSED NEAR AND JUST NORTH OF I-80 IN WESTERN/CENTRAL PENN OVER
THE NEXT SEVERAL HOURS AND WILL ALLOW THE EASTERN EDGE OF SHRA TO
MIGRATE TO BETWEEN KUNV AND KIPT AFT 04Z BEFORE FIZZLING OUT AND
SAGGING SLOWLY TO THE SOUTH AFTERWARD.

ATTEMPTED TO PAINT IN 0.10-0.25 OF AN INCH OF RAINFALL NEAR AND JUST
TO THE NORTH OF KFIG AND KDUJ THROUGH 07Z...WITH JUST A FEW
HUNDREDTHS AT BEST ELSEWHERE ACROSS THE WESTERN MTNS. SOME OF THE
TSRA NEAR AND JUST WEST OF KDUJ WERE TALL ENOUGH TO SUPPORT SMALL
HAIL. WESTERLY SHEAR IN THE LOWEST 1 KM IS JUST 15-20 KTS AND 850 MB
WINDS ARE AVERAGING 20-25 KTS...SO THE THREAT FOR STRONG WESTERLY
WIND GUSTS IS MINIMAL.

ELSEWHERE...SKIES WILL BE PARTLY TO MOSTLY CLOUDY WITH LITTLE OR NO
CHANCE FOR RAIN...ALONG WITH LIGHT SOUTHWESTERLY WINDS.

LATE EVENING TEMPS RANGING FROM THE MID AND UPPER 60S ACROSS THE
MTNS...TO BETWEEN 70-72F IN THE CENTRAL AND SOUTHERN VALLEYS ARE ON
TRACK TO REACH LOWS IN THE U50S TO NEAR 60F ACROSS THE MTNS...AND
LOWER TO MID 60S ELSEWHERE.

&&

.SHORT TERM /7 AM MONDAY MORNING THROUGH 6 PM MONDAY/...
THE FRONT STALLS OFF TO OUR SOUTH DURING THE DAY...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 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 /03Z MONDAY THROUGH FRIDAY/...
A NEARLY STATIONARY FRONTAL BOUNDARY LIES ALONG THE I-80 CORRIDOR
THIS EVENING...WHILE SOUTH OF THE FRONT A PLUME OF MOIST AIR IS
FLOWING ACROSS SOUTHERN PA ON A WESTERLY FLOW. CAN/T RULE OUT A
BRIEF SHRA/TSRA AT EITHER UNV OR IPT BTWN 04Z-06Z. HOWEVER...CONFIDENCE
NOT THAT HIGH ATTM BASED ON RADAR TRENDS.

THE BIGGEST AVIATION CONCERN WILL BE LATER TONIGHT ACROSS THE W
MTNS...WHERE THE PERSISTENT...MOIST WESTERLY FLOW ASCENDING THE
ALLEGHENY HIGHLANDS COULD RESULT IN SOME LOW CIGS...ESP AT JST. JST
REPORTING A 1300 FT CIG AT 03Z AND BULK OF LATEST MDL DATA SUPPORTS
IFR CIGS DEVELOPING LATE TONIGHT AT JST AS BLYR COOLS/MOISTENS.

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. 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/LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...DANGELO/LAMBERT
LONG TERM...RXR
AVIATION...FITZGERALD