359
FXUS61 KCTP 021137
AFDCTP
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
637 AM EST TUE DEC 2 2008
SYNOPSIS
A WEAKENING UPPER LEVEL TROF OVER THE GREAT LAKES WILL CONTINUE TO
SLOWLY WEAKEN AS IT PUSHES EAST THROUGH PENNSYLVANIA TODAY. A RIDGE OF
HIGH PRESSURE WILL BUILD ALONG THE EAST COAST WEDNESDAY...FOLLOWED
BY A STRONG COLD FRONT ON THURSDAY.
NEAR TERM /UNTIL 11 AM THIS MORNING/
BANDS OF SNOW SHOWERS ACROSS CENTRAL AND NORTHWEST SECTIONS...AND RAIN
AND SNOW SHOWERS ACROSS THE SOUTH...REMAIN ON THE LIGHT SIDE THROUGHOUT
CENTRAL PA...WHILE THE TROF BACKS THE BOUNDARY LAYER FLOW MORE WESTERLY.
LITTLE TO NO ACTIVITY HAS REACHED THE LOWER SUSQ...AS DOWNSLOPING
IS HAVING ITS WAY WITH THE LIMITED MOISTURE AND FORCING. THE
HEAVIEST SNOW BANDS ARE EXPECTED TO REMAIN NORTH OF THE NY BORDER...
BUT A FEW STEADIER BANDS OF SNOW ARE EXPECTED TO BRING A FEW
INCHES TO NORTHERN WARREN COUNTY...WITH LESSER AMOUNTS ELSEWHERE ACROSS
THE NW MTNS. MOST OF THE PRECIP WILL BE TAPERING OFF BY LATE
THIS MORNING AS DYNAMICS EXIT TO THE NORHTEAST.
SHORT TERM /11 AM THIS MORNING THROUGH 6 PM WEDNESDAY/
A PERIOD OF QUIETER WEATHER IS IN STORE FOR THE SECOND HALF OF
TODAY AND TONIGHT AS SURFACE HIGH BUILDS IN FROM THE SOUTH. AS
THE SFC RIDGE BUILDS INTO THE REGION...FALLING INVERSION HEIGHTS
AND BACKING LLVL FLOW /TO THE SW/ WILL BRING AN END TO THE SNOW
SHWRS BY THIS EVENING. A BRIEF PD OF SETTLED AND MILDER WEATHER IS IN
STORE FOR EARLY WEDNESDAY...EVENTUALLY YIELDING TO INCREASING
CLOUDS/MSTR AHEAD OF AN APPROACHING GRT LKS/MS VLY FNTL SYS LATE
IN THE DAY.
LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/
MDL AND ENSEMBLE DATA SHOW AN ELONGATED/SHARP CLD FNT PROGGED TO
TRAVERSE THE STATE ON THURSDAY. PLUMES CONTINUE TO INDICATE
RAIN/SNOW OVER THE WEST/CENTRAL MNTS...WITH MAINLY RAIN IN THE LWR
SUSQ VLY. PCPN SHOULD CHANGEOVER TO ALL SNOW BY LATE THURSDAY AS
THE COLDEST AIR OF THE SEASON IS FCST TO MOVE INTO THE REGION IN
THE WAKE OF THE FROPA /-2 TO -3SD 850MB TEMPS PER THE NAEFS/.
TEMPS MAY EVEN FALL /NON-DIURNAL TREND/ DURING THE LATE AFTN IN THE
WEST
THE LONGWAVE MEDIUM/LONG RANGE PATTERN SUGGESTED BY THE MODELS
GENERALLY SUPPORTS NEAR OR BELOW NORMAL TEMPERATURES AND ABOVE
NORMAL PRECIPITATION ACROSS THE EAST. THE HUDSON BAY
VORTEX/CYCLONIC FLOW WILL KEEP LAKE SNOW SHOWERS ACROSS THE
NORTH/WEST INTO THE FIRST HALF OF THE WEEKEND. A CLIPPER TYPE SYS
IS ALSO FCST TO SWING THROUGH THE REGION LATE SAT/SUN. THE MEAN
TROUGH POSITION BEGINS TO SHIFT EAST OF THE LAKES BY EARLY NEXT
WEEK...FOLLOWED BY A BRIEF WARMING TREND AND DRIER CONDITIONS
MON/TUE.
MEANWHILE...MDL AND ENSEMBLE GUID SHOWS A DEVELOPING TROUGH ACROSS
THE ROCKIES WITH A SIGNIFICANT PRECIPITATION EVENT POSSIBLE
DOWNSTREAM FOR THE MIDDLE OF NEXT WEEK.
AVIATION /12Z TUESDAY THROUGH SATURDAY/
AN UPPER LEVEL TROUGH CENTERED OVER THE GREAT LAKES WILL
SLOWLY WEAKEN AS IT PUSHES EAST ACROSS PENNSYLVANIA TODAY.
A FEW SNOW SHOWERS AROUND THE AREA THIS MORNING. AS WINDS
SHIFT MORE TO THE WEST THE NEXT FEW HOURS...SOME INCREASE
IN COVERAGE EXPECTED...BUT BY MID TO LATE AFTERNOON...THE
ACTIVITY WILL BE ON THE DECREASE AGAIN...AS HEIGHTS RISE...
AND WINDS SHIFT MORE TO THE SW.
BFD AND JST WILL HAVE MAINLY MVFR CONDITIONS EARLY ON...
PERHAPS IFR AT TIMES. UNV AND AOO AT TIMES WILL BE MVFR IN
SNOW SHOWERS...BUT MAINLY VFR TODAY. IPT AND MDT SHOULD
REMAIN VFR.
MORE IN THE WAY OF SW FLOW ON WED...AS THE SFC RIDGE BUILDS
OVER THE MID ATLANTIC AND SOUTHEASTERN STATES. NEXT FRONT
MOVES THROUGH LATER WED NIGHT AND EARLY THU BRINGING A FEW
RAIN SHOWERS.
A DRY SLOT WILL KEEP MOST OF THU DRY.
AS WINDS BECOME MORE WEST TO NORTHWEST THURSDAY NIGHT INTO
SAT...LAKE EFFECT SNOW SHOWERS AND SQUALLS COULD BECOME A
PROBLEM FOR THE NORTHWESTERN MOUNTAINS AND LAUREL HIGHLANDS.
LOOKS LIKE THE ACTION GETS GOING AFTER 06Z FRIDAY...BUT SOME
POSSIBLE PRIOR TO THIS TIME.
CTP WATCHES/WARNINGS/ADVISORIES
NONE.
SYNOPSIS...DEVOIR/RXR
NEAR TERM...DEVOIR/RXR
SHORT TERM...DEVOIR/STEINBUGL
LONG TERM...STEINBUGL
AVIATION...MARTIN
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page