SPC AC 290056
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0756 PM CDT THU MAY 28 2009
VALID 290100Z - 291200Z
...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF SWRN/CNTRL
TX...
...SWRN/SCNTRL TX...
WDLY SCTD STG-SVR TSTMS DEVELOPED THROUGH THE AFTN ALONG: 1/
RESIDUAL BOUNDARY THAT SETTLED SWD INTO CNTRL TX IN WAKE OF THE ERN
STATES TROUGH AND 2/ OUTFLOW BOUNDARIES FROM EPISODIC TSTM EVENTS
THE PAST 24-HRS. STRONGER STORMS HAVE BEEN FAVORING AREAS ACROSS
THE EDWARDS PLATEAU AND BIG COUNTRY WHERE THE BOUNDARY LAYER HEATED
THE MOST THIS AFTN /MLCAPES 1500-2000 J PER KG/. VERTICAL SHEAR OF
35-40 KTS AND PRESENCE OF STEEP LAPSE RATES HAVE CONTRIBUTED TO
SUPERCELL CHARACTERISTICS AND LARGE HAIL/DMGG WINDS CAN BE EXPECTED
UNTIL STORMS DIMINISH OVER THE BIG BEND REGION AND ERN EDWARDS
PLATEAU LATER THIS EVENING. IT DOES NOT APPEAR LIKELY THAT ANYTHING
MORE ORGANIZED WILL EVOLVE INTO SCNTRL TX OVERNIGHT. HERE...AIR
MASS HAS BEEN WORKED OVER FROM LAST NIGHTS ACTIVITY WITH SLIGHTLY
STRONGER CAP AND WEAKER INSTABILITY.
...UPR OH VLY/CNTRL-SRN APLCNS/SERN STATES...
PRIMARY UPR SUPPORT ASSOCD WITH THE EJECTING MID-LVL WAVE WAS
TRANSLATING INTO THE UPR OH VLY AND CNTRL APLCNS THIS EVENING. THE
ASCENT WAS SUPPORTING NUMEROUS TSTM CLUSTERS/LINE SEGMENTS...MOST OF
WHICH WERE SUB-SVR OWING TO TEMPERED BUOYANCY/LAPSE RATES.
HOWEVER...BELT OF 30-35 KTS OF WSWLY MID-LVL FLOW ATTENDANT WITH THE
DISTURBANCE WILL MAINTAIN A LOW RISK FOR ISOLD DMGG WIND GUSTS/HAIL
FROM ERN TN/CAROLINAS NWD INTO PA AND PARTS OF ERN OH THROUGH
MID-EVENING.
MEANWHILE...TO THE S ACROSS THE ERN GULF CST REGION...WDLY SCTD
TSTMS HAVE DEVELOPED AHEAD OF THE CDFNT SITUATED ACROSS AL AMIDST
MLCAPE OF A FEW HUNDRED J PER KG. MASS CONVERGENCE IS COMPARATIVELY
WEAK AT THIS LATITUDE AND GIVEN DECREASE IN PWATS/DRYING IN THE
COLUMN...THREAT FOR SUSTAINED SVR STORMS IS LOW...THOUGH A ROGUE STG
STORM WITH A DMGG WIND GUST/HAIL EVENT IS POSSIBLE.
...CNTRL SIERRA...
ISOLD TSTMS HAVE AGAIN DEVELOPED ALONG THE HIGHER TERRAIN AND WILL
PERSIST FOR A FEW MORE HOURS AS THEY MIGRATE INTO THE WRN FOOTHILLS.
ISOLD LARGE HAIL AND GUSTY WINDS WILL ACCOMPANY THE STRONGER CELLS.
..RACY.. 05/29/2009
CLICK TO GET WUUS01 PTSDY1 PRODUCT
NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 0600Z
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