Area Forecast Discussion
Issued by NWS State College, PA

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FXUS61 KCTP 051127
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
727 AM EDT SUN JUL 5 2015

.SYNOPSIS...
A RIDGE OF HIGH PRESSURE WILL DRIFT SLOWLY SOUTHEAST ACROSS
PENNSYLVANIA TODAY. AFTER AREAS OF DENSE FOG BURN OFF LATER THIS
MORNING...THIS WEATHER FEATURE WILL BRING DRY AND WARMER CONDITIONS
FOR THE REGION TODAY.

WARM AND HUMID CONDITIONS WILL MOVE BACK INTO PENNSYLVANIA EARLY
IN THE UPCOMING WEEK...AND SLOW MOVING UPPER AIR DISTURBANCE WILL
BRING SHOWERS AND ISOLATED THUNDERSTORMS BACK INTO THE REGION
FROM THE SOUTH MONDAY INTO MONDAY NIGHT. ANOTHER ROUND OF SHOWERS
AND THUNDERSTORMS IS EXPECTED FOR LATER TUESDAY AND TUESDAY NIGHT
AS A COLD FRONT APPROACHES FROM THE OHIO VALLEY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
EARLY MORNING 11-3.9U LOOP AND SFC OBS SHOWS FAIRLY WIDESPREAD
DENSE FOG OCCURRING ACROSS THE REGION SE OF THE ALLEGHENY
PLATEAU...WHERE EARLIER CLEAR SKIES AND CALM AIR COMBINED WITH
MOIST GROUND FROM YESTERDAY/S MDT-HVY RAINFALL TO STEADILY LOWER
VSBYS OVERNIGHT.

A LIGHT NW BREEZE AND NOTABLY LOWER SFC DEWPOINTS IN THE MID 40S
TO LOWER 50S HAS PREVENTED FOG SO FAR ACROSS THE LAUREL HIGHLANDS
AND NW MTNS...AND THAT SHOULD REMAIN TO BE THE CASE FOR THE SECOND
HALF OF THIS MORNING.

LOWS EARLY THIS MORNING WILL VARY FROM THE CHILLY MID-UPPER 40S
ACROSS THE NW MTNS...TO THE UPPER 50S AND LOWER 60S ACROSS THE
CENTRAL AND SE COUNTIES OF THE STATE.

1019 MB SFC HIGH INVOF KBFD AT 08Z WILL DRIFT SLOWLY SE ACROSS
THE CWA TODAY BRINGING ABUNDANT LATE MORNING AND AFTERNOON
SUNSHINE WITH MUCH WARMER TEMPS IN THE U70S...TO MID 80S IN THE
SUSQ VALLEY. POTENTIAL EXISTS FOR SMOKE FROM CANADIAN FOREST
FIRES DIMMING THE SUNSHINE A BIT.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/...
HIGH CLOUDS WILL GRADUALLY LOWER/THICKEN-UP FROM THE SW
TONIGHT/MONDAY MORNING AS A WELL-DEFINED /ALBEIT WEAK - 1016MB/
WAVE A OF LOW PRESSURE AT THE SFC AND ALOFT MOVES NE FROM THE
CENTRAL APPALACHIANS. PWATS INITIALLY AROUND 0.75 OF AN INCH THIS
EVENING WILL NEARLY DOUBLE BY 12Z MONDAY.

A MUCH MILDER NIGHT IS IN STORE FOR THE REGION WITH LOWS UP TO
10F HIGHER THAN EARLY SUNDAY ACROSS THE NRN AND WESTERN
MTNS...BUT JUST A FEW TO SVRL DEG HIGHER THROUGHOUT THE CENTRAL
MTNS AND MOST OF THE SUSQ VALLEY.

SHOWERS WILL BECOME LIKELY DURING THE DAY MONDAY...AND POPS OF
AROUND 60 PERCENT MAY BE TOO CONSERVATIVE. WILL ALLOW FUTURE MODEL
GUIDANCE TO HELP FINE-TUNE THE LOCATION AND TIMING OF MORE
DEFINABLE AREAS OF SHOWERS AND TSRA.

&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
THE HEART OF A VERY WARM AND MUGGY AIRMASS WILL BE OVER THE STATE
MONDAY NIGHT AND TUESDAY WITH MAINLY RAINFREE CONDITIONS BETWEEN
04-20Z TUESDAY. LATER TUESDAY AFTERNOON ISOLATED TO SCATTERED
CONVECTION WILL FORM INVOF A LEE TROUGH...AND IN ADVANCE OF A SFC
COLD FRONT APPROACHING FROM THE OHIO VALLEY.

MUCH OF THE ENERGY PUSHING THIS FRONT EASTWARD APPEARS THAT IT/LL
BE SHEARING OFF TO THE ENE ACROSS SRN ONTARIO AND QUEBEC. STILL A
CLOSE CALL ENOUGH CALL FOR ADEQUATE DEEP-LAYER SHEAR TO BRING
SCATTERED SHOWERS...AND ISOLATED STRONG TO POSSIBLY SVR TSRA
/MAINLY ACROSS THE WEST/ LATE IN THE DAY TUESDAY AND TUESDAY
NIGHT.

LOW TEMPS EARLY TUESDAY WILL BE IN THE L-M 60S ACROSS THE
MTNS...AND UPPER 60S TO AROUND 70F ACROSS THE CENTRAL AND SE
ZONES. HIGHS TUESDAY AFTERNOON WILL RANGE THROUGH THE 80S.

UPPER FLOW BECOMES FAIRLY ZONAL FOR THE MID TO LATE WEEK PERIOD
AND A WEAKENING CFRONTAL BOUNDARY SHOULD SAG JUST TO THE SOUTH OF
THE MASON DIXON LINE...WITH WEAK SFC RIDGING OVER THE STATE
THURSDAY AND FRIDAY. ANY ORGANIZED CONVECTIVE CLUSTERS MOVING
QUICKLY EAST FROM THE OHIO VALLEY IN FAST MID-UPPER LEVEL WESTERLY
FLOW WILL BE VERY DIFFICULT TO TIME AND NOT WORTH ASSIGNING ANY
MORE THAN 30-40 PERCENT POPS AT THIS POINT.

TEMPS AND SFC DEWPOINTS WILL TREND DOWN TO NEAR...OR JUST SLIGHTLY
BELOW NORMAL FOR THE SECOND HALF OF THE WEEK.

&&

.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
AREAS OF FOG AND LOW STRATUS AND ASSOCIATED SUB-VFR CONDITIONS
WILL DISSIPATE THRU 14-15Z...GIVING WAY TO A THICKENING HIGH
CIRRUS CANOPY INCREASING FROM THE S/W AND PREVAILING VFR FOR THE
REST OF THE DAY.

A CLOSED MID LEVEL SYSTEM WILL LIFT NORTHEAST FROM THE TN VALLEY
TONIGHT INTO THE CENTRAL APPALACHIANS BEFORE SHEARING OUT OVER
THE NRN MID ATLANTIC MONDAY INTO TUESDAY. AN INCREASINGLY MOIST
SOUTH TO SOUTHEAST LOW LEVEL FLOW IN ADVANCE OF THIS SYSTEM WILL
LKLY BRING LOW VFR TO MVFR CIGS INTO THE AIRSPACE ALONG WITH SHRA
AND ISOLD TSTMS MONDAY INTO MONDAY NIGHT. A COLD FRONT SHOULD
BRING ANOTHER ROUND OF SHRA/TSTMS TO THE AREA ON TUESDAY INTO
WEDNESDAY. THE FRONT IS FCST TO STALL OUT NEAR THE PA/MD BORDER
WHICH WILL ALLOW FOR ADDITIONAL OPPORTUNITIES FOR PCPN THROUGH THE
END OF THE WEEK.

OUTLOOK...

WED-THU...VFR/MVFR WITH CHC OF SHOWERS/PM TSTMS.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 9 AM EDT THIS MORNING FOR PAZ012-018-
019-025>028-034>037-041-042-045-046-049>053-056>059-063>066.

&&

$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...LAMBERT/MARTIN
AVIATION...STEINBUGL



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