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000
ACUS03 KWNS 220731
SWODY3
SPC AC 220730

DAY 3 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0230 AM CDT WED MAY 22 2013

VALID 241200Z - 251200Z

...NO SVR TSTM AREAS FORECAST...

...SYNOPSIS...
SOME EWD PROGRESSION OF THE ERN U.S. TROUGH IS FORECAST THIS
PERIOD...WHICH WILL ALLOW THE CENTRAL U.S. RIDGE TO BROADEN EWD
SOMEWHAT -- THOUGH PROGGED TO REMAIN FIXED OVER THE CENTRAL U.S.
THROUGH THE PERIOD.  MEANWHILE...THE WRN U.S. TROUGH IS EXPECTED TO
REMAIN IN PLACE...THOUGH THE EMBEDDED UPPER LOW OVER THE PAC NW MAY
LIFT SLOWLY NWD/NEWD WITH TIME.

AT THE SURFACE...EXPECT THE ERN U.S. COLD FRONT TO MOVE OFFSHORE
EARLY...TRAILING WWD ACROSS N FL...THE GULF COAST...AND INTO TX
DURING THE AFTERNOON.  MEANWHILE...A COLD FRONT WILL LINGER ACROSS
THE INTERMOUNTAIN WEST...WHILE A LEE TROUGH RESIDES ACROSS THE
LENGTH OF THE HIGH PLAINS THROUGH THE PERIOD.

...HIGH PLAINS FROM SERN MT/SWRN ND SWD TO ERN NM/FAR W TX...
AS ISOLATED TO SCATTERED CONVECTION LIKELY ONGOING EARLY IN THE
PERIOD SHIFTS EWD ACROSS THE PLAINS...A DESTABILIZING BUT GENERALLY
CAPPED BOUNDARY LAYER IS EXPECTED TO EXIST W OF THE ONGOING
PRECIPITATION -- ALONG AND AHEAD OF THE LEE TROUGH FORECAST TO
RESIDE OVER THE HIGH PLAINS.  SCATTERED STORM REDEVELOPMENT IS
FORECAST INVOF THE LEE TROUGH BY MID TO LATE AFTERNOON -- AS WEAK
MID-LEVEL VORTICITY MAXIMA TRANSLATE EWD INTO THE MEAN RIDGE
POSITION.  WITH GENERALLY MODEST /AOB 30 KT/ MID-LEVEL WLYS FORECAST
ATOP LOW-LEVEL SELYS...SHEAR MARGINALLY SUPPORTIVE OF
ORGANIZED-ROTATING UPDRAFTS WILL EXIST -- PARTICULARLY WHERE
LOW-LEVEL FLOW MAY BE LOCALLY STRONGER/MORE VEERED.  THIS
COMBINATION OF AMPLE SHEAR/INSTABILITY BUT MEAN LARGE-SCALE RIDGING
SUGGESTS THAT SEVERE THREAT WILL REMAIN ISOLATED IN GENERAL -- AND
THUS WILL INTRODUCE ONLY A BROAD 5% THREAT AREA OVER THE HIGH PLAINS
ATTM.  POCKETS OF GREATER THREAT MAY BE ABLE TO BE DISCERNED IN
LATER FORECASTS WHICH COULD WARRANT EVENTUAL INSERTION OF SMALL
SLIGHT RISK AREAS.

..GOSS.. 05/22/2013