Area Forecast Discussion
Issued by NWS State College, PA

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS61 KCTP 311933
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
333 PM EDT THU JUL 31 2014

.SYNOPSIS...
A CLOSED UPPER LEVEL LOW PRESSURE CENTERED OVER JAMES BAY WILL
LIFT SLOWLY NORTHEAST LATE TODAY. THE TRAILING LONG WAVE TROUGH
WILL SHARPEN UP OFF TO OUR WEST THROUGH THE WEEKEND...HELPING TO
DRAW INCREASING MOISTURE INTO THE REGION FROM THE SOUTH. THIS WILL
LEAD TO PERIODS OF UNSETTLED CONDITIONS FOR LATER FRIDAY...RIGHT
THROUGH THE UPCOMING WEEKEND. TEMPERATURES WILL REMAIN COOLER
THAN NORMAL.

&&

.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
CHAOTIC SKY COVER NOTED ON THE REGIONAL VIS SATELLITE IMAGERY WITH
A FEW ISOLATED SHOWERS DEVELOPING OVER THE LAURELS AND CENTRAL
RIDGE AND VALLEY REGION AT 1830Z. THIS /SO FAR/ WEAK AND LOW-
TOPPED CONVECTION WAS FORMING RIGHT WITHIN A WAVY...NEARLY EAST-
WEST RIBBON OF ENHANCED 0-3KM...AND SFC-900MB ML CAPE OF UP TO 500
J/KG.

17Z HRRR LOOKS TO HAVE A DECENT HANDLE ON THE CURRENT LOCATION
/AND TREND OF THIS LATE AFTERNOON CONVECTION/...FOCUSING IT OVER
THE NEXT SEVERAL HOURS ACROSS THE LOWER SUSQ AND SOUTHERN POCONOS
WHERE SOME LOW-TOPPED TSRA WILL ALSO BE POSSIBLE. POPS WILL STILL
ONLY BE AROUND 30-40 PERCENT GIVEN THE EXPECTED SCATTERED CVRG.

ELSEWHERE...WILL BROAD-BRUSH THE REGION WITH SCHC POPS FOR A STRAY
SHOWER  OR TSRA.

WINDS WILL GO L/V TONIGHT UNDER A RIDGE OF HIGH PRESSURE WITH
GENERALLY PARTLY CLOUDY /ALTO CU OR HIGH BASED STRATO CU/.

LOW TEMPS WILL BE NEAR 50F ACROSS THE NORTH AND NEAR 60 IN THE
SOUTHEAST.

&&

.SHORT TERM /6 AM FRIDAY MORNING THROUGH 6 PM FRIDAY/...
NEAR NORMAL PWATS OF AROUND /OR SLIGHTLY UNDER ONE INCH/ WILL
GRADUALLY INCREASE TO OVER 1.5 INCHES ACROSS THE SE THIRD-HALF OF
THE CWA BY 00Z SAT AS DEEPENING SOUTHERLY FLOW DEVELOPS.

CLOUDS WILL LIKELY BE ON THE INCREASE THROUGHOUT THE DAY
/INITIALLY BEING FUNNELED UP THROUGH THE CENTRAL MTNS AND LOWER
SUSQ VALLEY DURING THE MORNING AND MIDDAY HOURS/...WHICH SHOULD
LIMIT SFC BASED CAPES TO GENERALLY 1000 J/KG OR LESS. AS THE RIGHT
ENTRANCE REGION OF A 75KT SWRLY JET LIFTS NORTH ACROSS THE SCENT
ZONES AND SUSQ VALLEY...THE CHANCE FOR SHOWERS AND PERHAPS A FEW
TSRA WILL INCREASE TO 40-60 PERCENT BY THE MID AFTERNOON HOURS.

TEMPS DO GET NEARER TO NORMAL ON FRIDAY WITH HIGHS IN MID TO UPPER
70S NORTH TO LOWER 80S IN THE SE.

&&

.LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/...
VERY LITTLE CHANGE OVERALL FROM YESTERDAY`S LONG RANGE OUTLOOK AS
GLOBAL MODELS AND ENSEMBLES DEPICT THE CURRENTLY HIGH AMPLIFIED
WESTERN RIDGE EASTERN TROF PATTERN FLATTENING SOMEWHAT THROUGH EARLY
NEXT WEEK...BUT OVERALL MAINTAINING THEIR POSITIONING. BY MID
WEEK... INCREASING CONFLUENCE OVER THE CANADIAN ROCKIES AND
STRENGHTENING NORTHWEST FLOW DOWNSTREAM WILL HELP NUDGE THE EASTERN
UNITED STATES TROF OFFSHORE...ONLY TO BE REPLACED BY ANOTHER
CANADIAN TROF TOWARDS THE END OF THE PERIOD.

DIURNALLY DRIVEN SCATTERED CONVECTION APPEARS TO BE A DAILY
OCCURRENCE FRI-SUN...BUT DEEP MOISTURE DURING THAT TIME REMAINS
ANCHORED ALONG THE I-95 CORRIDOR SO AMOUNTS ARE NOT EXPECTED TO BE
HAVY AND COVERAGE IS NOT EXPECTED TO BE GREATER THAN 30-40% EACH
DAY.

THE BACKING NORTHWEST FLOW BY EARLY NEXT WEEK APPEARS TO SPELL
DRYING FOR A FEW DAYS BEFORE RETURN FLOW AND ONE OF SEVERAL UPSTREAM
TROFS BRINGINS A CHANCE OF SHOWERS ON WEDNESDAY...AND ANOTHER
BRINGS A CHANCE OF SHOWERS OR THUNDERSTORMS AT THE END OF THE WEEK.

TEMPERATURES THROUGHOUT THE PERIOD WILL BE NEAR TO SLIGHTLY BELOW
NORMAL FOR MOST OF THE PERIOD...AS THE MEAN TROF AXIS REMAINS OVER
THE EASTERN SEABOARD KEEPING SIGNIFICANT HEAT AT BAY THROUGH THE
PERIOD. MON AND TUE SHOULD BE THE TWO SUNNIEST AND WARMEST
DAYS...WITH MAXES RANGING FROM THE LOWER TO MIDDLE 80S. TEMPS START
COOL DOWN SLIGHTLY ON WED AND THU AS ONE OF THE AFOREMENTIONED
CANADIAN UPPER TROFS CROSS THE REGION BY WEDNESDAY NIGHT.

&&

.AVIATION /20Z THURSDAY THROUGH TUESDAY/...
A CLOSED UPPER LEVEL LOW PRESSURE CENTERED OVER JAMES BAY WILL
LIFT SLOWLY NORTHEAST LATE TODAY.

WIDESPREAD VFR...WITH BRIEF MVFR CIGS AND VSBYS IN COMPACT
SHOWERS AND TSRA WILL OCCUR THROUGH 23Z.

WILL CONTINUE TO MENTION VCSH AT KIPT...KMDT AND KLNS FOR A 3-4
HOUR PERIOD DURING THE MID TO LATE AFTERNOON HOURS TODAY AS HIGH
RES MODELS SHOW ISOLATED TO SCATTERED SHOWERS BECOMING FOCUSED
ACROSS THAT REGION.

ISOLATED-SCATTERED CONVECTION CAN/T BE RULED OUT ELSEWHERE ACRS
THE CENTRAL AND WESTERN PA AIRFIELDS LATE THIS AFTERNOON.
HOWEVER...THE OVERALL PROBABILITY IS TOO LOW TO MENTION IN MOST OF
THE INDIVIDUAL TERMINALS. LIGHT WINDS PICK UP TO AROUND 10 MPH
FROM THE SW TODAY...BEFORE BECOMING LIGHT AGAIN TONIGHT.

JUST AN OUTSIDE CHANCE FOR A SHOWER IN THE NORTH TONIGHT.
OTHERWISE GENERALLY QUIET WEATHER WITH SOME PATCHY 2-4SM FOG
DEVELOPING AGAIN AFTER MIDNIGHT.

OUTLOOK...
FRI-SUN...SCT PM TSRA IMPACTS POSSIBLE.
MON...SLOW IMPROVEMENT EXPECTED WITH AREAS OF MVFR POSSIBLE
MAINLY IN THE MORNING.

&&

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

&&

$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...DEVOIR
AVIATION...LAMBERT


USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.