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000
ACUS03 KWNS 210730
SWODY3
SPC AC 210729

DAY 3 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0229 AM CDT TUE MAY 21 2013

VALID 231200Z - 241200Z

...THERE IS A SLGT RISK OF SVR TSTMS TX/OK PANHANDLE VICINITY...

...SYNOPSIS...
AN ERN NOAM UPPER TROUGH IS FORECAST TO CONTINUE EWD THIS
PERIOD...WHILE UPSTREAM RIDGING SPREADS EWD INTO THE CENTRAL U.S.
AHEAD OF THE NEXT UPPER SYSTEM.  THIS SYSTEM -- A LARGE/VERY UPPER
LOW OVER THE PAC NW...WILL MAKE VERY LITTLE PROGRESS THROUGH THE
PERIOD.

AT THE SURFACE...A COLD FRONT CROSSING MT/WY/THE GREAT BASIN WILL --
LIKE ITS PARENT UPPER SYSTEM -- MAKE ONLY SLOW EWD PROGRESS.
MEANWHILE...A SECOND FRONT WILL CONTINUE ADVANCING ACROSS THE NERN
U.S. TOWARD THE ATLANTIC COAST.

...TX/OK PANHANDLE VICINITY...
SUBSIDENCE/CAPPING IS FORECAST ACROSS THE SRN HIGH PLAINS REGION
UNDER THE EVOLVING UPPER RIDGE.  HOWEVER...STRONG INSTABILITY ABOVE
THE CAP AND STRONGLY VEERING FLOW WITH HEIGHT OTHERWISE INDICATE
SOME POTENTIAL FOR SEVERE WEATHER.

MODELS -- TO VARYING DEGREES -- DO FORECAST AT LEAST ISOLATED STORM
INITIATION INVOF THE TX/OK PANHANDLE VICINITY.  ANY STORM WHICH
COULD DEVELOP WOULD LIKELY ORGANIZE RAPIDLY AND BECOME
SEVERE/SUPERCELLULAR.  THUS -- WILL INTRODUCE CONDITIONAL SLIGHT
RISK ACROSS THIS REGION...WITH REFINEMENTS LIKELY TO BE NEEDED IN
LATER FORECASTS AS CONVECTIVE POTENTIAL BECOMES MORE CLEAR.

...NEW ENGLAND SWD ACROSS THE MID-ATLANTIC REGION...
AMPLE FLOW ALOFT BUT WEAK INSTABILITY SHOULD CHARACTERIZE THE
PRE-FRONTAL WARM SECTOR ACROSS THE NORTHEAST AND MID-ATLANTIC REGION
THURSDAY.  THUS -- OVERALL SEVERE POTENTIAL APPEARS RELATIVELY LOW
ATTM.  WILL INTRODUCE LOW SEVERE WEATHER PROBABILITY ACROSS THIS
AREA FOR ISOLATED HAIL/WIND THREAT WHERE A FEW STRONGER AFTERNOON
STORMS CAN FORM...BUT WILL WAIT UNTIL LATER OUTLOOKS TO ISSUE A MORE
SPECIFIC/POSSIBLY HIGHER-PROBABILITY FORECAST.

..GOSS.. 05/21/2013