FXUS61 KCTP 052047
AFDCTP
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
347 PM EST SAT DEC 5 2009
.SYNOPSIS...
LOW PRESSURE OFF THE MID-ATLANTIC COAST WILL LIFT NORTHEASTWARD
TONIGHT...WITH SNOW TAPERING OFF FROM WEST TO EAST. HIGH PRESSURE
OVER THE TENNESSEE VALLEY WILL BUILD INTO THE REGION ON SUNDAY.
NEXT WEEK LOOKS MORE UNSETTLED WITH A SERIES OF WEATHER SYSTEMS
SET TO IMPACT THE REGION THROUGH MID-WEEK.
&&
.NEAR TERM /UNTIL 10 PM THIS EVENING/...
REGIONAL RADAR STILL SHOWS A SOLID BAND OF LIGHT TO MODERATE
DEFORMATION/FGEN SNOW PIVOTING NEWD ACROSS CENTRAL AND ERN PENN.
HAVE ADJUSTED TIMING OF THE WWY TO INDICATE AN EARLIER
EXPIRATION...AS LATEST MODEL TRENDS SUGGEST A FASTER ADVANCE AND
EVENTUAL EXITING OF THE SNOWFALL ACROSS THE AREA. SNOWFALL AMOUNTS
WILL AVERAGE BTWN 2-4 INCHES FOR THE MOST PART. SEE THE LATEST
SNOWFALL SUMMARY /PNSCTP/ FOR MORE DETAILS.
&&
.SHORT TERM /10 PM THIS EVENING THROUGH 6 PM SUNDAY/...
LINGERING SNOW SHOWERS OR FLURRIES MAY CONTINUE AFTER
MIDNIGHT DOWNWIND OF THE LAKES...AS LLVL FLOW BACKS TO NWLY.
BKN-OVC STRATOCU WILL PERSIST INTO THE FIRST HALF OF SUNDAY WITH
MORE BREAKS IN THE SE GIVEN DOWNSLOPE. OTHERWISE...HIGH PRES
BUILDING NEWD FM THE TN VLY WILL PROVIDE FAIR WX. CUT MINS BY A
FEW DEGS TNT AS THE GUID NOT LKLY ACCOUNTING FOR FRESH SNOW COVER.
&&
.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
FOCUS IN THE EXTENDED PERIODS RESIDES AROUND MID-WEEK STORM. MON/TUE
WILL FEATURE AN AMPLIFYING EAST COAST RIDGE...WITH A THERMAL RIDGE
POOLING NORTH ALONG LEE-SIDE OF THE APPALACHIANS. SFC RIDGE MON
PUSHES OFF NJ COAST...WHICH MAY ALLOW WEAK VORT MAX TO SLIDE ACROSS
LK ERIE AND BRING LGT PRECIP TO THE NW MTNS MON/EARLY TUE. THEN WEAK
ANTI-CYCLONIC FLOW RETURNS FOR TUE AHEAD OF HIGH CONFIDENCE STORM
MID-WEEK.
ATTM THE MID-WEEK SYSTEM HINGES ON WHERE 500MB TROUGH DEPARTS
ROCKIES TUE/WED. PRECIP SHUD RETURN TUE NGT AS A WEAK FRONTAL BNDRY
LIFTS NORTH. EXPECT TEMPS TO WARM TO ABV FREEZING FOR MUCH OF THE
CWFA AND ALLOW SHRA AT ONSET. MINIMAL SPREAD AMONGST ENSEMBLE
MEMBERS FOR PRECIP ON WED...SO HAVE MAINTAINED A HIGH POPS. TIMING
OF FRONTAL PASSAGE REMAINS DIFFICULT AT THIS TIME...HOWEVER IT
APPEARS AS TROUGH BECOMES NEGATIVELY TILTED THUR A COASTAL LOW WILL
FORM. ENSEMBLE SUGGEST SFC VORT SHUD PASS NW OF THE CWFA WED EVE.
FLOW REMAINS VERY PROGRESSIVE WITH SEVERAL GEFS MEMBERS ADVERTISING
A 130-150KT 300MB JET THUR/FRI. THIS SHUD PROVIDE A GOOD SCENARIO IN
THE BNDRY LYR FOR LES ACROSS THE NW MTNS/UPSLOPE SNOW FOR LAUREL
HIGHLANDS. 850MB TEMPS CONSIDERABLY COOLER AT -14 TO -16 DEG C
THUR/FRI...WITH A FEW MEMBERS POINTING TOWARDS -16 TO -18 DEG C.
ATTM FEEL GIVEN CONSID CLOUD COVER DURING DAYLIGHT HOURS TEMPS WILL
HOLD IN THE 20S/30S FOR THE END OF THE WEEK...HOWEVER IF SKIES CAN
CLEAR TEMPS WILL EASILY COOL OVERNIGHT.
&&
.AVIATION /21Z SATURDAY THROUGH THURSDAY/...
BANDED SNOWFALL...AND ASSOC IFR/LIFR CONDS...WILL TAPER OFF FROM
WEST TO EAST ACROSS CENTRAL PENN THRU LATE THIS AFTN AND INTO THE
EVENING. OVERALL HAVE INDICATED IMPROVING CIGS AND VSBYS THRU TNT.
OCNL -SHSN MAY LINGER AT JST/BFD AS LLVL FLOW BACKS TO NWLY. HIGH
PRES WILL EVENTUALLY PROVIDE GENERAL VFR FLYING BY SUN AFTN.
OUTLOOK...
MON...CHC SHSNRA WEST. VFR LIKELY EAST.
TUE...CHC MVFR CIGS WEST.
VFR LIKELY EAST.
WED...POTENTIAL RAIN/ICE ALONG WITH IFR CONDS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR
PAZ019-026>028-035-036-042-045-046-049>053-056>059-063>066.
WINTER WEATHER ADVISORY UNTIL 6 PM EST THIS EVENING FOR PAZ024-
025-033-034.
&&
$$
SYNOPSIS...STEINBUGL
NEAR TERM...STEINBUGL
SHORT TERM...STEINBUGL
LONG TERM...BEACHLER
AVIATION...STEINBUGL
