000 
ACUS03 KWNS 260958
SWODY3
SPC AC 260933
 
STORM PREDICTION CENTER...NWS/NCEP...NORMAN OK
DAY 3 CONVECTIVE OUTLOOK...REF AWIPS GRAPHIC PGWK48 KWNS.
 
VALID 281200-291200
 
THERE IS A SLIGHT RISK OF SVR TSTMS FOR THE PA/NY AREA.

...SYNOPSIS...
A STRONG SHORTWAVE TROUGH...NOW OVER SRN CA...IS EXPECTED TO MOVE
OVER THE SRN ROCKIES TODAY...THE MID MS VALLEY TOMORROW...AND
CONTINUE EWD FROM THE GREAT LAKES/OH VALLEY TO NEW ENGLAND ON DAY
3.  AT THE SURFACE...A DEEP CYCLONE WILL MOVE EWD ACROSS THE PA/NY
AREA IN ADVANCE OF THE MID LEVEL TROUGH.

...PA/NY AREA...
THE CONTINENTAL POLAR AIR MASS NOW COVERING THE ERN CONUS SHOULD
ERODE FROM THE SW AS THE DEEP LOW APPROACHES...ALLOWING LOW-LEVEL
MOISTURE NOW NEAR THE GULF COAST TO SPREAD AS FAR NEWD AS PA/NY. 
GIVEN THE REASONABLE AGREEMENT AMONGST THE MODEL FORECASTS... IT
SEEMS PLAUSIBLE THAT A WARM SECTOR WITH VERY STRONG DEEP LAYER WIND
FIELDS AND AT LEAST WEAK INSTABILITY WILL BECOME ESTABLISHED AS FAR
NE AS PA/NY DURING THE DAY.  ASCENT WITH THE SURFACE LOW/MID LEVEL
TROUGH SHOULD PROVIDE A FAVORABLE ENVIRONMENT FOR THUNDERSTORM
DEVELOPMENT...WITH THE THREAT FOR A FEW FAST MOVING SEVERE STORMS. 

...APPALACHIANS TO OH/TN VALLEYS...
FARTHER SW ALONG THE TRAILING SURFACE COLD FRONT...THERE WILL ALSO
BE THE POSSIBILITY OF THUNDERSTORM DEVELOPMENT IN AN ENVIRONMENT OF
MODERATE-STRONG MID LEVEL FLOW AND MODERATE INSTABILITY.  THOUGH
THUNDERSTORM INITIATION/COVERAGE WILL BE LESS CERTAIN WELL SW OF
THE SURFACE LOW...STORMS THAT FORM WILL HAVE SOME POTENTIAL TO
BECOME SEVERE.
 
..THOMPSON.. 04/26/02