FXUS61 KPBZ 100813
AFDPBZ
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
313 AM EST THU DEC 10 2009
.SYNOPSIS...
GUSTY WINDS WILL REMAIN ACROSS THE AREA TODAY BEFORE BEGINNING TO
DIMINISH. TEMPERATURES FOR THE REST OF THE WORK WEEK WILL BE
SHARPLY COLDER BEHIND YESTERDAYS COLD FRONT.
&&
.NEAR TERM /THROUGH TONIGHT/...
SOME WRAPAROUND MOISTURE ASSOCIATED WITH A LOW PRESSURE SYSTEM OVER
CANADA WILL ALLOW SCATTERED SNOW SHOWERS TO CONTINUE TODAY.
LOCATIONS NORTH AND EAST OF PITTSBURGH COULD SEE ANYWHERE FROM A
DUSTING TO AN INCH OF ACCUMULATION. THE PRESSURE GRADIENT WILL
REMAIN TIGHT BETWEEN THE DEPARTING LOW AND HIGH PRESSURE OVER THE
CENTRAL PLAINS...KEEPING WINDS GUSTY THROUGHOUT THE DAY. SOME
LOCATIONS IN THE HIGHEST ELEVATIONS MAY FLIRT WITH WIND ADVISORY
CRITERIA...BUT WITH LOW CONFIDENCE IN ANY WIDESPREAD 45 MPH
GUSTS...WILL NOT ISSUE AN ADVISORY AT THIS TIME. HIGHS WILL BE MUCH
COLDER THAN YESTERDAY...SOME 15-20 DEGREES BELOW NORMAL.
AS LOW LEVEL MOISTURE DIMINISHES...SNOW SHOWERS ARE EXPECTED TO COME
TO AN END OVERNIGHT. WINDS SHOULD ALSO BEGIN TO DECREASE DURING THIS
TIME PERIOD...ALTHOUGH WIND GUSTS UP TO 30 MPH WILL STILL BE
POSSIBLE. WIND CHILL ADVISORIES COULD BE NEEDED FOR THE HIGHER
ELEVATIONS OF WEST VIRGINIA AND MARYLAND OVERNIGHT...WITH LOWS
AROUND 10 ABOVE AND STRONG WINDS REMAINING OVER THE AREA.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY/...
HIGH PRESSURE WILL SLOWLY MAKE ITS WAY TO THE NORTHEAST FRIDAY INTO
SATURDAY...ALLOWING FOR DECREASING WINDS AND CLOUD COVER. FLOW OUT
OF THE SOUTH SHOULD ALLOW TEMPERATURES TO BEGIN MODERATING FOR THE
WEEKEND. NEXT SYSTEM DEVELOPING ALONG THE SOUTHEASTERN U.S. COULD
CLIP THE FORECAST AREA ON SUNDAY...AND WITH BETTER AGREEMENT
BETWEEN THE GFS/ECMWF...HAVE SLIGHTLY INCREASED POPS FOR THIS TIME
PERIOD. CURRENT FORECASTED TEMPERATURES WOULD ALLOW FOR A MIX OF
RAIN AND SNOW IN MOST LOCATIONS.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
THE NEXT COLD FRONT APPROACHING FROM THE WEST WILL BRING
SCATTERED POPS FOR SNOW SHOWERS AND SNOW SHOWERS MIXED WITH RAIN
SOUTH MONDAY NIGHT AND TUESDAY. SURFACE RIDGE WILL BUILD BACK
INTO THE REGION WEDNESDAY WITH MAINLY DRY CONDITIONS EXPECTED.
TEMPERATURES ARE EXPECTED TO BE WITHIN A FEW DEGREES OF NORMAL FOR
THE EXTENDED PERIOD.
&&
.AVIATION /08Z THURSDAY THROUGH MONDAY/...
GENERAL MVFR CONDITIONS MAY BE EXPECTED AT MOST PORTS THROUGH THE
MORNING AS COLD AIR CONTINUES TO FLOW OVER THE UPPER OHIO VALLEY
WITH THE ADVANCE OF MID/UPPER LEVEL LOW PRESSURE TROUGH. AREAS OF
LIGHT SNOW, WITH SCATTERED SNOW SHOWERS EMBEDDED OCCASIONALLY
DROPPING VISIBILITY, WILL CONTRIBUTE TO THE SITUATION AS WILL
CONTINUED WIND GUSTS TO NEAR 30 KTS. FALLING TEMPERATURE ABOVE THE
BOUNDARY LAYER ARE EXPECTED TO DEEPEN THE MIXING LAYER AFTER
DAYBREAK; HENCE, SNOW SHOWERS WITH MVFR CEILINGS WERE CONTINUED AT
ALL BUT ZZV AND MGW INTO THE AFTERNOON, AS WERE WIND GUSTS TO NEAR,
OR SLIGHTLY IN EXCESS OF 30KTS.
VFR CONDITIONS ARE ANTICIPATED AS HIGH PRESSURE BUILDS LATE THURSDAY
AND INTO FRIDAY. THAT HIGH SHOULD PROVIDE GOOD FLIGHT WEATHER UNTIL
ANOTHER LOW MOVES ON THE GREAT LAKES AND DETERIORATES CONDITIONS FOR
SUNDAY AND MONDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
