-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KCTP 130307
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1107 PM EDT SAT JUL 12 2014

.SYNOPSIS...
HIGH PRESSURE WILL DRIFT EAST OFF THE MID ATLANTIC COAST SETTING
UP AN INCREASINGLY HUMID AIR FLOW OVER THE REGION. A PAIR OF COLD
FRONTS EARLY NEXT WEEK WILL EVENTUALLY USHER IN COOLER AND DRIER
AIR FOR MIDWEEK. THE COOL CONDITIONS WILL LAST THROUGH LATE WEEK.

&&

.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
RADAR SHOWS ONE LONELY SHOWER JUST EAST OF
WILLIAMSPORT...OTHERWISE IT`S DRY WITH JUST SOME THIN HIGH
CLOUDINESS DRIFTING ACROSS.

I USED THE LATEST HRRR AND NAM AND BACKED OFF ON THE TIMING OF
THE SHOWERS EXPECTED TO MOVE INTO THE NWRN ZONES LATER TONIGHT.

A POTENT SHORT WAVE IS HELPING ORGANIZE A LINE OF STORMS FROM
WISCONSIN TO SOUTHERN MISSOURI. THIS WILL PUSH SHOWERS AND
THUNDERSTORMS INTO NWRN ZONES AROUND OR SHORTLY AFTER SUNRISE.

INCREASING HIGH CLOUDS OVERNIGHT WILL HELP KEEP MIN TEMPS ABOVE
NORMAL...ONLY DROPPING INTO THE LOW TO MID 60S REGION-WIDE.

&&

.SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
SFC COLD FRONT WILL BE SLIDING GRADUALLY SE ACROSS THE GLAKES
SUNDAY...REACHING A LINE FROM NEAR CYYZ TO KTOL TO KIND AROUND 00Z
MONDAY.

REMNANT MID AND HIGH CLOUDS ARE EXPECTED FOR THE MORNING/MIDDAY
HOURS SUNDAY...FROM THE POTENTIAL UPSTREAM MCS. SCATTERED
SHRA/ISOLATED TSRA WILL DRIFT QUICKLY EAST /AT 35-40 KTS/ ACROSS
THE NORTHERN MTNS BETWEEN 12-16 SUNDAY.

AFTERWARD...A COMPLEX CLOUD/LLVL HEATING PATTERN WITH SEVERAL
OUTFLOW BOUNDARIES WILL FIRE OFF NEW /AND LOCALLY STRONG TO SVR
TSRA/ AS MEAN SFC BASED CAPES VIA THE SREF RAMP UP TO BETWEEN
1000-1500 J/KG...WITH POCKETS OF LOCALLY HIGHER INSTABILITY NEAR
2500 J/KG /VIA THE 12Z NAM/.

WHAT SIGNIFICANT POCKETS OF HIGHER CAPES CAN DEVELOP...THEY/LL
HAVE THE OPPORTUNITY TO COMBINE WITH MODERATELY STRONG SPEED AND
DIRECTIONAL SHEAR TO CREATE EHI/S OF 1.5-2.5 M2/S2. SPC ALSO NOTES
THAT MODEL HODOGRAPHS FAVOR BOWING LINE SEGMENTS AND EVEN A FEW
SUPERCELLS/BRIEF TORNADOES ACROSS THE CWA. THEIR DAY 2 SLIGHT RISK
AREA FOR SUNDAY COVERS A LITTLE MORE THAN THE SE HALF OF PENN.

THERE SHOULD BE 2-3 PRIMARY AREAS OF CONVECTION...THE FIRST BEING
DEVELOPING ACROSS CENTRAL/NRN PENN INVOF OF OUTFLOW
BOUNDARIES...THE SECOND NEAR THE LEE TROUGH ACROSS THE CENTRAL
MTNS AND SUSQ VALLEY...AND THE THIRD FORMING ACROSS THE WRN
MTNS...ALONG AND AHEAD OF THE APPROACHING CFRONT.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
THE FOCUS FOR THE BEST CONVERGENCE SHIFTS SLOWLY EAST ACROSS THE
AREA SUNDAY NIGHT AND MONDAY. HEIGHT FALLS OF 10DAM ARE EXPECTED
MONDAY AS A SIGNIFICANT TROUGH PUSHES FORCIBLY INTO THE NRN GREAT
LAKES. SPC HAS MOST OF THE CWA /EXCEPT FOR THE FAR NW ZONES/ IN
THE SLIGHT RISK AREA FOR MONDAY.

THE STORMS BOTH SUNDAY AND MONDAY WILL BE MOVING PRETTY FAST FROM
WEST TO EAST...BUT TRAINING IS POSSIBLE DUE TO THE E-W BAROCLINIC
ZONE.

PWATS INCREASE TO NEAR 2 INCHES ON MONDAY. THUS...SOME HEAVY RAIN
AND PERHAPS LOCALIZED FLOODING ARE POSSIBLE. CURRENTLY...3HR FFG
ACROSS THE REGION IS IN THE 2.5 TO 3.5 INCH RANGE...WHICH WILL
TEMPER THE RISK OF FLASH FLOODING UNLESS SEVERAL TSRA CAN TRAIN
OVER THE SAME LOCATIONS OVER THE SPAN OF JUST A FEW HOURS. SEVERAL
ROUNDS OF SHOWERS/TSRA SHOULD LOWER THESE FFG VALUES BY MONDAY
WHEN THE CFRONT MOVES THROUGH. WILL NOT MENTION FLOODING IN THE
HWO YET...BUT WILL CONTINUE TO MENTION THE POSSIBILITY OF SEVERE
TSRA MICROBURSTS.

 THE GFS AND NAM GUIDANCE IS MUCH QUICKER TO PUSH THE FRONT
THROUGH...WITH THE ECMWF DEEPENING THE UPPER LEVEL TROUGH...THOUGH
THE LATEST RUN HAS OPENED UP THE CLOSED LOW. HOWEVER THE GFS
BRINGS IN THE DRIER AIR THROUGH QUICKER...KEEPING ALL BUT THE ERN
THIRD OF THE AREA DRY ON TUESDAY. THE EC DEVELOPS A COHERENT SFC
LOW OVER THE MID MS VALLEY AND MOVES IT TO OUR W/N ON TUESDAY AS
IT DEEPENS TO NEAR 1003MB. WILL THEREFORE KEEP ON WITH MENTIONS OF
SHRA/TSRA FOR THE ENTIRE SHORT TERM PERIOD.

HIGH AMPLITUDE RIDGE/TROUGH PATTERN DEVELOPS ACROSS THE MUCH OF
NORTH AMERICA BEGINNING LATE IN THE WEEKEND...AND CONTINUES
THROUGH THE FIRST HALF OF NEXT WEEK.

THE BRUNT OF THE GREATEST 850-700 MB TEMP ANOMALIES AND
ASSOCIATED BELOW NORMAL 500 MB HEIGHTS WILL BE AIMED AT THE LOWER
OHIO VALLEY AND MID MISS VALLEY TUESDAY AND WEDNESDAY...WITH OUR
REGION RESIDING ON THE ACTIVE/EASTERN SIDE OF THIS SLOW MOVING
FEATURE.

AS ADDITIONAL ENERGY IS DRIVEN SSE INTO THE BACK SIDE OF THE HIGH
AMPLITUDE MIDWEST TROUGH...PROLONGED HIGH PWAT AIR /AND LIFT
BENEATH THE RIGHT ENTRANCE REGION OF AN UPPER JET/ MAY LINGER
ACROSS THE SERN ZONES WITH SCATTERED...MAINLY AFTERNOON TSRA
WEDNESDAY AFTERNOON.

THE PATTERN OVER THE NRN CONUS AND SRN CANADA APPEARS TO DE-
AMPLIFY LATER NEXT WEEK AS THE EASTERN U.S. TROUGH BEGINS TO SHEAR
OUT TO THE NE.

THE DRIEST PERIOD OF THE LONG TERM WILL BE THURSDAY AND
FRIDAY...THOUGH SOME ISOLATED CONVECTION STILL CANT BE RULED OUT
EITHER OF THOSE TWO DAYS.

TEMPS START OUT AOA NORMAL PRECEDING THE CFROPA NEXT SUNDAY...AND
PERHAPS MONDAY ACROSS THE SE ZONES...THEN COOL TO AT LEAST  4-6F
BELOW NORMAL FOR DAYTIME HIGHS TUESDAY THROUGH THURSDAY. TEMPS
WILL LIKELY REBOUND TO NEAR NORMAL LATE NEXT WEEK.

&&

.AVIATION /03Z SUNDAY THROUGH THURSDAY/...
MAINLY VFR CONDITIONS...CLEAR SKIES AND CALM WINDS...WILL PREVAIL
ACROSS PENNSYLVANIA TONIGHT.

MVFR FOG IS POSSIBLE ACROSS THE CENTRAL VALLEYS AND SUSQUEHANNA
REGION TAF SITES EARLY SUNDAY MORNING. RESIDUAL MOISTURE FROM
RAINFALL SATURDAY EVENING WILL AID IN FOG FORMATION AT KMDT AND
KLNS.

AN APPROACHING WARM FRONT WILL BRING THE CHANCE OF TSRA IMPACTS
TO THE NW MTNS SUNDAY. RA CHANCES AND CLOUD COVER WILL INCREASE
FROM NW TO SE THROUGHOUT THE DAY...BUT SITES WILL REMAIN MAINLY
VFR THROUGH THE TAF PERIOD. BRIEF REDUCTIONS IN VSBY AND CIGS ARE
POSSIBLE TOMORROW AFTERNOON IN THUNDERSTORMS.

OUTLOOK...

SUN...BRIEF THUNDERSTORM IMPACTS POSSIBLE.

SUN NIGHT-MON NIGHT...NUMEROUS SHOWERS/TSRA WITH MAINLY BRIEF
PERIODS OF IFR TO MVFR.

TUES-WED...THUNDERSTORM IMPACTS POSSIBLE...MAINLY IN THE
AFTERNOON.

THU...NO SIG WX EXPECTED.

&&

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

&&

$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...DANGELO/LAMBERT
LONG TERM...DANGELO/CERU
AVIATION...LAMBERT/COLBERT