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 191221
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
821 AM EDT FRI SEP 19 2014

.SYNOPSIS...
GENERALLY FAIR WEATHER WILL BE INTERRUPTED FRIDAY NIGHT AND
SATURDAY MORNING AS ATLANTIC MOISTURE POOLS OVER THE CENTRAL PA
MOUNTAINS. A FRONTAL SYSTEM WILL BRING A CHANCE OF SHOWERS TO THE
REGION ON SUNDAY...BEFORE ANOTHER LARGE AREA OF HIGH PRESSURE
BRINGS MORE FAIR AND COOL WEATHER FOR MOST OF NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LOW CLOUDS OVER THE NORTHERN MOUNTAINS ARE NOT AN UNINTERRUPTED
SHEET. BUT THEY ARE RATHER PERSISTENT AROUND POTTER/MCKEAN/WARREN
COS. PATCHY MID CLOUDS ALSO HANGING OVER THE LAURELS/SC MTNS.
HOWEVER...SUNRISE SHOULD HELP THE LOWER CLOUDS BREAK UP. TEMPS
SHOULD RISE NICELY...REACHING INTO 60S AND L70S. THESE VALUES ARE
JUST A FEW DEGS BELOW NORMAL FOR THE BEGINNING OF FALL.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SATURDAY/...
HIGH PRESSURE MOVING OFF THE NEW ENGLAND COAST TONIGHT WILL FORCE
A LONG-FETCH OFF THE ATLANTIC TO ASCEND THE MOUNTAINS OF CENTRAL
PA. THIS SHOULD CREATE A BLANKET OF CLOUDS AND DRIZZLE/FOG AS IT
SETTLES IN THROUGH THE NIGHT. BUT...THE WINDS CONTINUE TO VEER
ON SATURDAY AND SHOULD ALLEVIATE THE LOW-CLOUD PROBLEM LATE IN
THE MORNING AND EARLY AFTERNOON ON SATURDAY. SO OVERNIGHT MINS
WILL LIKELY BE A TOUCH ABOVE NORMAL. WITH THE EXPECTED INCREASE
IN SUNSHINE THROUGH THE DAY...MAXES WILL TRY TO RUN UP INTO THE
70S FOR MOST PLACES - ESP IN THE VALLEYS OF THE SE WHERE THERE
SHOULD BE LESS CLOUD COVER. WILL HOLD THE TEMPS AROUND 70F ALONG
THE SPINE OF THE MOUNTAINS WHERE THE CLOUDS WILL TAKE LONGEST TO
BREAK.

&&

.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
A SHORTWAVE DROPPING OUT OF CANADIAN ROCKIES WILL BEGIN TO CARVE
OUT A TROUGH OVER THE GREAT LAKES AS A DEVELOPING SYSTEM
APPROACHES PA FOR SUN/MON. ABOVE NORMAL TEMPERATURES ARE EXPECTED
SUNDAY WITH TEMPS MAINLY IN THE 70S...AND TAKING A RUN AT 80F IN
THE SE. WE/LL ALSO GET A BREAK FROM OUR RUN OF CHILLY OVERNIGHTS
AS LOWS REMAIN AROUND 60F SAT NIGHT.

THE CENTER OF THE APPROACHING LOW PRESSURE SYSTEM WILL REMAIN WELL
TO OUR NORTH...BUT A WEAK COLD FRONT WILL PUSH THROUGH PA SUNDAY
INTO SUN NIGHT. THIS WILL BE THE BEST CHANCE OF RAIN/SHOWERS
THROUGH DURATION OF THE EXTENDED FORECAST. THE LATEST ECMWF/GFS
GENERALLY AGREEING ON POTENTIAL FOR A TENTH TO POTENTIALLY A
QUARTER OF AN INCH OF QPF.

THE 500 HPA TROUGH BEHIND THE FRONT BOTTOMS OUT OVER THE REGION
MONDAY. THIS WILL KEEP MENTION FOR SCT INSTABILITY SHOWERS...MAINLY
IN HIGHER TERRAIN OF N/W CWA. COOLER AIR ON NW FLOW WILL GRADUALLY
FILTER BACK INTO THE REGION...WITH MONDAY/S HIGHS ABOUT 8-10F
COOLER AND TUESDAY SLIPPING ANOTHER COUPLE OF DEGREES AS TROUGH
LIFTS AWAY TO THE NE.

LOOKS LIKE LOWS IN THE MID/UPPER 30S AGAIN BECOME LIKELY ACROSS
THE NORTHERN MTNS FOR MIDWEEK AS LARGE AREA OF HIGH PRESSURE
SETTLES IN OVER NEW ENGLAND. TEMPS WILL GRADUALLY WARM HEADING
INTO NEXT WEEKEND.

&&

.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
A LARGE AND RATHER STRONG AREA OF SURFACE HIGH PRESSURE CENTERED
NEAR OTTAWA ONTARIO THIS MORNING WILL CREATE A LIGHT EAST TO
NORTHEAST WIND AT ALL TAF SITES TODAY...BEFORE THE WIND DIRECTION
VEERS AROUND TO THE EAST-SOUTHEAST TONIGHT.

THE MAIN AVIATION CONCERN FOR THE NEXT FEW HOURS WILL BE THE
AREAS OF LOW CIGS/STRATUS CLOUDS AND SOME LOCALIZED VSBYS AOB 1SM
OVER THE ALLEGHENY PLATEAU...THE RESULT OF A RELATIVELY MOIST
EASTERLY FLOW ASCENDING THE HIGHER TERRAIN OF CENTRAL PA.

11-3.9 MICRON SATL IMAGERY AND SFC OBS AT 11Z CONTINUE TO SHOW
WIDESPREAD CIGS AOB 1000 FT AGL FORMING/DRIFTING SLOWLY WESTWARD
ACROSS THE NORTHERN MTNS OF PA INVOF KBFD CIGS AT KBFD HAVE BEEN
HOLDING PRETTY STEADY BETWEEN 700-900 FT AGL FOR THE ENTIRE
OVERNIGHT AND WILL BEGIN TO DISSOLVE/MIX-OUT QUICKLY BETWEEN
13-14Z TODAY.

ELSEWHERE ACROSS CENTRAL PENN AND THE SUSQ VALLEY...MOST OF THE
SCT CLOUDS WERE IN THE FORM OF EITHER VFR STRATO CU...OR CIRRUS.

VFR EXPECTED IN ALL AREAS AFTER 14Z TODAY...THROUGH 04-06ZZ
SATURDAY.

WIDESPREAD LOWS CIGS IN THE LOW MVFR TO IFR RANGE /WITH SOME
DRIZZLE/ LOOK LIKELY AT MANY AIRFIELDS LATE TONIGHT THROUGH THE
MORNING HOURS SATURDAY AS THE SERLY-SOUTHERLY LLVL FLOW
TRANSPORTS ATLANTIC MOISTURE /FROM NEAR THE VA/NC COAST/ OVER THE
APPALACHIANS. LLWS IS ALSO PROBABLE AT ALL TAF SITES LATE TONIGHT
AND SATURDAY MORNING THANKS TO A MODERATELY STRONG SOUTHERLY WIND
OF 30-35 KTS AT 1.5-2KFT AGL TOPPING THE 5-10KT SSERLY SFC WIND.

OUTLOOK...
SAT...AM LOW CIGS/FOG POSSIBLE.
SUN...SLIGHT CHC OF PM TSRA IMPACTS W MTNS.
MON-TUE...NO SIG WX EXPECTED.

&&

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

&&

$$
SYNOPSIS...DANGELO
NEAR TERM...DANGELO/GARTNER
SHORT TERM...DANGELO
LONG TERM...RXR
AVIATION...LAMBERT


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