SPC AC 161642
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1142 AM CDT TUE JUN 16 2009
VALID 161630Z - 171200Z
...THERE IS A SLGT RISK OF SVR TSTMS MID MS VALLEY INTO SC AND GA...
...THERE IS A SLGT RISK OF SVR TSTMS PARTS OF ERN CO...
...SYNOPSIS...
HEIGHTS WILL BE RISING OVER CENTRAL U.S. THRU THE PERIOD AS TROUGH
SHARPENS ACROSS SRN CA. THIS WILL RESULT IN STRONGER WESTERLIES
SHIFTING NWD IN THE PLAINS ALONG WITH WARMER AIR AT MID LEVELS
GRADUALLY DECREASING CONVECTIVE CONCERN FROM SOUTH TO NORTH.
MEANWHILE THE MATURE MCS/COLD POOL CONTINUES EWD ACROSS MID MS INTO
OH/TN VALLEYS THIS AFTERNOON PROVIDING A FOCUS FOR SEVERE
THUNDERSTORMS.
...MID MS VALLEY INTO KY/TN TODAY...
THE MCS OVER SRN MO HAS A WELL DEFINED COLD POOL AND REAR INFLOW JET
OF 50-60KT AS SAMPLED BY VAD WINDS AT SGF 88D AND THE CONWAY
PROFILER. WITH MLCAPES CLIMBING TO AOA 2000 J/KG WITH LITTLE CINH
BY EARLY AFTERNOON...WIND DAMAGE EXPECTED TO INCREASE ASSOCIATED
WITH THE BOWING LINE OF THUNDERSTORMS AS IT TRACKS EWD ACROSS KY/TN.
STORMS ARE EXPECTED TO FINALLY WEAKEN AFTER SUNSET OVER
THE CENTRAL APPALACHIANS.
...NORTHERN OK/SOUTHERN KS THIS AFTERNOON...
WITH THE UPPER RIDGE BUILDING ACROSS THE CENTRAL AND SOUTHERN PLAINS
THIS AFTERNOON...THERE WILL BE A TENDENCY TO WARM THE MID LEVELS AND
INCREASE THE CAPPING INVERSION ACROSS PARTS OF TX/OK.
NEVERTHELESS...THE OUTFLOW BOUNDARY LEFT FROM OVERNIGHT
CONVECTION EXTENDS ACROSS NORTHERN OK AND MAY BE THE FOCUS FOR
ISOLATED THUNDERSTORM DEVELOPMENT BY LATE AFTERNOON. HOT
TEMPERATURES AND AMPLE LOW LEVEL MOISTURE WILL YIELD HIGH CAPE
VALUES AND SUGGEST THAT ANY STORM THAT CAN BE SUSTAINED WILL LIKELY
BE SEVERE.
...EASTERN SD INTO EASTERN KS/WESTERN MO...
STRONG HEATING WILL OCCUR ALONG AND WEST OF THE LARGE CLOUD SHIELD
SHIFTING EWD ACROSS CENTRAL U.S...BUT UPPER RIDGING IS ALSO FORECAST
TO OCCUR. PRESENT INDICATIONS ARE THAT ISOLATED THUNDERSTORMS WILL
DEVELOP ALONG THIS CORRIDOR AROUND PEAK HEATING AND PERSIST FOR A
FEW HOURS BEFORE WEAKENING. SUFFICIENT WESTERLY FLOW ALOFT AND
EFFECTIVE DEEP LAYER SHEAR VALUES SUPPORT A RISK OF SUPERCELLS
CAPABLE OF LARGE HAIL AND DAMAGING WINDS.
...EASTERN CO...
A BAND OF STRONG SOUTHWESTERLY FLOW WILL REMAIN ACROSS CO TODAY WITH
SUFFICIENT LOW LEVEL MOISTURE FOR SCATTERED SHOWER AND THUNDERSTORM
DEVELOPMENT. FORECAST SOUNDINGS AND MODEL GUIDANCE SUGGEST A RISK
OF A FEW SEVERE STORMS BY LATE AFTERNOON OR EARLY EVENING. HAIL
SHOULD BE THE MAIN THREAT.
..HALES/GARNER.. 06/16/2009
CLICK TO GET WUUS01 PTSDY1 PRODUCT
NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 2000Z
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