SPC AC 221228
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0728 AM CDT TUE SEP 22 2009
VALID 221300Z - 231200Z
...NO SVR TSTM AREAS FORECAST...
...SRN TX INTO THE MID SOUTH/MID MS RIVER VALLEY...
AXIS OF RICH MOISTURE CONTINUES AHEAD OF STRONG SFC COLD FRONT NOW
ADVANCING ESEWD FROM CENTRAL TX INTO THE UPPER MS RIVER VALLEY AND
WEST OF SFC HIGH PRESSURE RIDGE PERSISTING ALONG THE EAST COAST.
PWS FROM 1.75-2 INCHES /UPPER 60S-LOWER 70S F SFC DEW POINTS/ ARE IN
PLACE WITHIN THIS AXIS EXTENDING FROM THE TX COAST NWD INTO THE
LOWER OH/MID MS RIVER VALLEYS AT DAYBREAK...AND SHOULD PERSIST FOR
MUCH OF THE DAY. DESPITE THE RICH MOISTURE IN PLACE...LOW AND DEEP
LAYER SHEAR WILL BE MODEST AS STRONGEST FLOW ALOFT REMAINS NEAR DEEP
CLOSED LOW OVER STABLE POST-FRONTAL AIR MASS ACROSS THE CENTRAL/SRN
PLAINS. HOWEVER...EFFECTIVE SHEAR FROM 20-30 KT MAY STILL SUPPORT
BRIEF ORGANIZED STORMS AS ACTIVITY INCREASES DURING THE DAY WITH
AFTERNOON HEATING...GIVEN EXPECTED MODERATE INSTABILITY. ISOLATED
HAIL AND DAMAGING WINDS COULD ACCOMPANY STRONGER CORES ACROSS THIS
REGION...HOWEVER OVERALL SEVERE THREAT SHOULD REMAIN TEMPERED BY
WEAK LAPSE RATES AND LIMITED SHEAR.
..EVANS/JEWELL.. 09/22/2009
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NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1630Z
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