FXUS61 KCTP 060856
AFDCTP
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
356 AM EST SUN DEC 6 2009
.SYNOPSIS...
HIGH PRESSURE WILL BUILD INTO THE REGION SUNDAY INTO
MONDAY...ALTHOUGH SOME LIGHT SNOW SHOWERS WILL BE POSSIBLE MONDAY
IN THE NORTHERN MOUNTAINS. UNSETTLED WEATHER IN STORE FOR MIDWEEK
AS A STORM SYSTEM BRINGS SOME SNOW AND RAIN TUE NIGHT INTO WED
THEN COLDER TEMPERATURES AND SCATTERED SNOW SHOWERS FOR LATE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
HIGH PRESSURE BUILDING INTO THE REGION WILL BRING MAINLY QUIET
WEATHER TODAY AND TONIGHT...WITH THE EXCEPTION BEING SOME
SCATTERED FLURRIES ACROSS THE NORTHERN TIER EARLY TODAY. IT WILL
BE MOSTLY SUNNY TO PARTY CLOUDY AREAWIDE THIS AFTERNOON...WITH
MID-HIGH CLOUDS WORKING IN OVERNIGHT. TEMPS SHOULD RUN NEAR OR
JUST SLIGHTLY BELOW NORMAL...MAINLY IN AREAS WITH FRESH SNOW
COVER.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY/...
MON/MON NIGHT WILL BRING FLAT FLOW WITH A WEAK VORT MAX SLIDING
ACROSS LAKE ERIE WHICH WILL BRING LGT PRECIP MAINLY CONFINED TO
THE NW MTNS. THEN WEAK ANTI-CYCLONIC FLOW RETURNS FOR TUE WITH
BUILDING E COAST RIDGE AHEAD OF HIGH CONFIDENCE STORM...THE IMPACT
OF WHICH WILL BEGIN TO ARRIVE TUE NIGHT AND LAST THROUGH MID-WEEK.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
FOCUS IN THE EXTENDED PERIODS RESIDES AROUND HIGH CONFIDENCE MID-
WEEK STORM WHICH MODELS HAVE BEEN ADVERTIZING FOR SEVERAL DAYS
NOW. THIS SYSTEMS ULTIMATE IMPACT ON PA HINGES ON WHERE 500MB
TROUGH DEPARTS ROCKIES TUE/WED. PRECIP MOVES IN TUE NGT AS A WEAK
FRONTAL BNDRY LIFTS NORTH AHEAD OF DEEPENING SURFACE LOW WHICH
WILL TRACK NE THROUGH OHIO VALLEY. CENTRAL PA WILL REMAIN ON E
SIDE OF THE LOW...WHICH WILL EVENTUALLY PUSH WARM AIR INTO THE
REGION. BUT TUE NIGHT WHEN PRECIP BEGINS TEMPS SHOULD BE COLD
ENOUGH TO START OFF AS SNOW...AND COULD SEE A COUPLE OF INCHES
ACCUMULATE. BUT WARM AIR WILL STREAK IN AS TEMPS WARM ABV
FREEZING BY 12Z WED IN THE SOUTH AND A COUPLE OF HOURS LATER IN
THE NORTH. HIGH POPS REMAIN JUSTIFIED...AND EVEN BUMPED THEM UP
ANOTHER NOTCH WITH THIS PACKAGE AS QPF FOR THE 18-24 HOUR PERIOD IS
AROUND AN INCH. TROUGH DOES BECOME MORE NEGATIVELY TILTED LATER
WED INTO THU AS A COASTAL LOW FORMS OFF NEW ENGLAND COAST...BUT
ENSEMBLE SUGGESTS SFC VORT SHUD PASS NW OF THE CWA BY THEN.
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 /08Z SUNDAY THROUGH THURSDAY/...
RESIDUAL MOISTURE ASCENDING THE ALLEGHENIES WILL PRODUCE PERIODS
OF MVFR STRATOCU AT CENTRAL AND WRN AIRFIELDS...
KBFD/KJST/KAOO/KUNV OVERNIGHT ALONG WITH A FEW FLURRIES. HI PRES
BUILDING OVR THE REGION SHOULD ENSURE VFR FLYING ON SUNDAY ALONG
WITH LGT WINDS.
OUTLOOK...
MON...CHC AFTN SHSN WEST. VFR LIKELY EAST.
TUE...CHC MVFR CIGS WEST. VFR LIKELY EAST.
WED...POTENTIAL RAIN/ICE ALONG WITH IFR CONDS.
THU...STRONG/GUSTY NW WIND.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...RXR
NEAR TERM...RXR
SHORT TERM...RXR/STEINBUGL
LONG TERM...BEACHLER/RXR
AVIATION...FITZGERALD/GARTNER
