Area Forecast Discussion
Issued by NWS State College, PA

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FXUS61 KCTP 311104
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
704 AM EDT MON AUG 31 2015

.SYNOPSIS...
A MODERATELY HIGH AMOUNT OF MOISTURE STREAMING EAST FROM THE OHIO
VALLEY WILL EXTEND ACROSS PENN THROUGH MUCH OF THIS WEEK. THE
CLOSE PROXIMITY OF A NEARLY EAST-WEST FRONTAL BOUNDARY ACROSS
PENNSYLVANIA WILL LEAD TO ISOLATED MAINLY AFTERNOON AND EARLY
EVENING SHRA/TSRA TODAY THROUGH THURSDAY.

HIGH PRESSURE OFF THE EAST COAST WILL RIDGE NORTHWEST INTO
PENNSYLVANIA AND LEAD TO TEMPERATURES WELL ABOVE NORMAL THIS
ENTIRE WEEK. IT WILL FEEL MORE LIKE THE MIDDLE OF SUMMER THAN
SEPTEMBER.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SFC HIGH PRESSURE LOCATED JUST OFF THE SE U.S. COAST WILL SLOWLY
BUILD NORTHWEST...AS AN UPPER RIDGE LOCATED OVER THE UPPER GLAKES
AND MISS VALLEY MOVES EAST TO THE OHIO RIVER VALLEY AND MID
ATLANTIC REGION BY 12Z TUES.

925-850 MB THETA-E RIDGE EXTENDS FROM THE OHIO VALLEY...ENE THROUGH
PENN EARLY TODAY...WITH A WEAK/STALLED-OUT SFC FRONT EXTENDING
FROM DETROIT...SW TO ST LOUIS. THE NORTHERN PART OF THIS FRONT
WILL MOVE STEADILY EAST/SOUTHEAST AND BECOME LOCATED ACROSS
CENTRAL PENN THIS EVENING...AND STAY THERE THROUGH MUCH OF
TUESDAY. A BIT OF DRYING WILL BE SEEN ACROSS THE REGION NEAR AND
TO THE NORTH OF INTERSTATE 80.

03Z SREF PROB OF CAPE EXCEEDING 1000 J/KG CLIMBS TO THE 60-80
PERCENT RANGE THIS AFTERNOON...HOWEVER THE PROB OF 2000 J/KG IS
VERY LOW AT 10 PERCENT OR LESS TODAY THROUGH THURSDAY...THUS THE
LOW DIURNAL POP/CVRG FOR CONVECTION. 07Z HRRR CONFIRMS THIS
THINKING AS IT PLACES GENERALLY ISOLATED- SCATTERED/POPCORN LIKE
COVERAGE BETWEEN 17Z-22Z TODAY.

PLENTY OF BKN-OVC ALTO CU /TOPPED BY SOME CIRRUS/ BLANKETED THE
SE HALF TO TWO-THIRDS OF PENN EARLY TODAY...WHILE MOSTLY CLEAR
SKIES AND THE COOLEST TEMPS IN THE L60S WERE FOUND INVOF KBFD.
ELSEWHERE...TEMPS RANGED FROM THE MID 60S TO MID 70S - A RATHER
MUGGY EARLY MORNING FOR THE FINAL DAY OF METEOROLOGICAL SUMMER.

ASIDE FROM A HIGHLY ISOLATED AND BRIEF LIGHT SHOWER OR TWO ON THE
RADAR SCOPE EARLY TODAY...CONDITIONS ACROSS MUCH OF CENTRAL AND
NORTHERN PENN WILL BE DRY WITH A VERY LIGHT AND VARIABLE WIND
THROUGH THE MID MORNING HOURS.

FARTHER SOUTH...WEAK UPPER LOW OVER THE WESTERN CAROLINAS WILL
LIFT NORTHWARD OVERNIGHT ON THE WESTERN PERIPHERY OF THE SPRAWLING
WESTERN ATLANTIC UPPER HIGH CIRCULATION. THIS WILL MAINTAIN THE
FOCUS FOR POOLING MOISTURE AND FORCING FOR SHOWER ACTIVITY THROUGH
THE PRE DAWN HOURS ACROSS MY FAR SOUTH. AGAIN...AREAS TO THE
NORTH SHOULD BE DRY AFTER 06Z AS DEFORMATION LESSENS AND FORCING
FOCUS SHIFTS TO AREAS ALONG AND SOUTH OF MY SOUTHERN TIER.

SOME FOG HAS FORMED...BUT VSBYS ARE HOLDING UP AOA 1 SM

MINS AROUND SUNRISE TODAY WILL RUN IN THE 60S IN PRACTICALLY ALL
LOCATIONS AS DEWPOINTS SHOULD NOT GO ANY LOWER THAN 60F. A FEW OF
THE NORMALLY COLD SPOTS NEAR...AND THE EAST OF KBFD WILL SEE A LOW
TEMP IN THE MID 50S.

HIGH TEMPS THIS AFTERNOON WILL VARY FROM THE U70S OVER THE HIGHEST
ELEVATIONS OF THE NORTH AND WEST...TO THE MID AND UPPER 80S ACROSS
OUR SE ZONES.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM TUESDAY/...
TONIGHT SHOULD BE A NEAR REPEAT OF SUNDAY NIGHT/EARLY MONDAY WITH
VARIABLE AMTS OF MAINLY MID AND HIGH CLOUDS AND PERHAPS JUST A
COUPLE SMALL SHOWERS ROAMING THE STREETS.

CONSALL TEMP BLEND YIELDS LOWS AROUND 60F ACROSS THE NRN
MTNS...AND IN THE MID TO UPPER 60S ELSEWHERE.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
ANOMALOUS UPPER LEVEL RIDGE WILL DOMINATE THE OHIO VALLEY AND
EASTERN UNITED STATES MUCH OF THE UPCOMING WEEK...WITH LATEST
GUIDANCE REMAINING FIRM FOR AN EXTENDED RUN OF 850HPA TEMPS
PEAKING DAILY AROUND 16-18C. THIS WILL TRANSLATE TO WELL ABOVE-
NORMAL SFC TEMPS. THIS WARMTH AND INCREASING HUMIDITY SHOULD ALLOW
FOR AT LEAST A SLIGHT CHC FOR DIURNAL CONVECTION EACH DAY...BUT
WARM MID-LEVELS WILL KEEP THE PROBABILITY OF WIDESPREAD RAINFALL
QUITE LOW.

BEST CHANCES FOR PRECIP WILL BE DURING THE MID-LATE WEEK PERIOD
/WED-THU-FRI/ WITH A COUPLE SUBTLE FEATURES. FIRST...A WEAK UPPER
LEVEL WAVE /BEST PROGGED ON THE ECMWF/ SLIPS OVERHEAD ON WED AS
BERMUDA HIGH BRIEFLY RECEDES. AT SAME TIME A WEAK BACKDOOR COLD
FRONT SLIPS SOUTHWARD OFF THE EAST COAST. THIS COULD HELP POOL
SOME LOW LEVEL MOISTURE OVER THE MID ATLANTIC AND OHIO VALLEY AS
MID LEVELS COOL JUST A BIT...BRINGING POTENTIAL FOR SCT TSTMS.
RIDGE BUILDS BACK IN FOR FRI...BUT ANOTHER SURFACE BACKDOOR FRONT
TRIES TO SLIP ACROSS THE STATE AS SURFACE HIGH EXPANDS IN FROM THE
NORTH. THIS BOUNDARY SHOULD BRING SCT CONVECTION FOR FRI.

EXTENDED MODELS HINT AT POTENTIAL FOR DAILY CONVECTION CONTINUING
INTO THE WEEKEND ALONG SOUTHER BORDER...BUT OVERALL CONDITIONS
WILL BE MAINLY RAIN-FREE.

TEMPS PEAK MIDWEEK WITH READINGS APPROACHING 90F IN THE SE...AND
EVEN GETTING INTO THE 80S ELSE HERE...EASILY WELL ABOVE NORMAL
FOR THE FIRST WEEK OF SEPT. LOWS WILL ALSO REMAIN QUITE MILD
MID/LATE WEEK AS HIGH HUMIDITY AIR HANGS AROUND. SLIGHTLY COOLER
BUT STILL ABOVE AVERAGE TEMPS WILL CONTINUE THROUGH THE WEEKEND.

&&

.AVIATION /12Z MONDAY THROUGH FRIDAY/...
EARLY MORNING FOG HAS REMAINED ISOLATED AT IPT AND BFD...WITH IFR
AND MVFR RESPECTIVELY. ANY AM VALLEY FOG WILL BURN OFF BY LATE
AM. OTHERWISE...WIDESPREAD VFR CONDS AND LIGHT WIND APPEAR VERY
LIKELY MONDAY WITH ONLY ISOLD LATE DAY SHRA/TSRA POSSIBLE...AS
HIGH PRESSURE BUILDS OFF THE MID ATLANTIC COAST. SHOWERS WILL BE
MOST LIKELY THROUGH THE SOUTHERN TAF SITES WITH LNS AND MDT MOST
LIKELY...MAINLY BETWEEN NOW AND THROUGH THE EARLY AFTERNOON HOURS.

OUTLOOK...

TUE-FRI...PATCHY AM FOG POSS...MAINLY KBFD. ISOLD PM TSRA IMPACTS
POSSIBLE.

&&

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

&&

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



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