SPC AC 251608
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1108 AM CDT MON AUG 25 2008
VALID 251630Z - 261200Z
...THERE IS A SLGT RISK OF SVR TSTMS PARTS OF AL...WRN GA AND FL
PANHANDLE...
...AL/FL/GA...
WHILE THE REMNANT CENTER OF FAY CONTINUES TO SLOWLY FILL OVER
CENTRAL MS...A MDT SLY LOW LEVEL FLOW OF 30-40KT CONTINUES TO THE E
OF THE CIRCULATION OVER AL. THE COMBINATION OF A VERY MOIST/TROPICAL
AIR MASS COUPLED WITH THE ENHANCED SHEAR AND HELICITY IN THE
BOUNDARY LAYER WILL CONTINUE TO SUPPORT LOW LEVEL ROTATION EMBEDDED
IN LINE SEGMENTS CURRENTLY TRACKING NWD THRU ERN AL INTO FAR WRN GA.
MODELS SUGGESTING THE LOW CENTER ITSELF WILL CONTINUE TO GRADUALLY
FILL AND DRIFT NWD POSSIBLY INTO WRN TN BY 12Z TUE. HOWEVER THE SLY
GRADIENT IN THE ERN SEMI-CIRCLE WILL BE SLOW TO WEAKEN... WHILE
SLOWLY DEVELOPING A LITTLE FURTHER N AND E INTO WRN GA. THUS
ISOLATED TORNADOES AND WIND DAMAGE WILL CONTINUE TO BE A THREAT INTO
THIS EVENING.
REF SWOMCD 2153 FOR ADDITIONAL SHORT-TERM DISCUSSION ON THIS AREA.
...SWRN AZ/SERN CA...
T.S. JULIO HAS MOVED NWD PAST 24 HOURS AND IS NOW LOCATED OVER
CENTRAL BAJA PENINSULA. A SUBSTANTIAL INCREASE IN MOISTURE IS
UNDERWAY IN ADVANCE OF JULIO INTO SRN AZ/SERN CA. WHILE CLOUDINESS
WILL SLOW HEATING SOME IN SERN AZ...STILL EXPECT STRONG SOLAR
INSOLATION TO DEVELOP STEEP LOW/MID LAPSE RATES FROM SWRN AZ WWD
INTO IMPERIAL VALLEY. WITH PRECIPITABLE WATER APPROACHING 2 INCHES
...AFTERNOON HEATING WILL RAISE MLCAPES TO AOA 2000 J/KG SWRN DESERT
VALLEYS. OVERALL SHEAR WILL BE WEAK...LESS THAN 10KT...THUS
THUNDERSTORMS EXPECTED TO FORM INITIALLY OVER HIGHER TERRAIN AND
PROPAGATE INTO DESERTS VALLEYS. LOCALIZED DAMAGING WINDS WILL BE
POSSIBLE LATER THIS AFTERNOON AND EVENING HOWEVER LACK OF ANY
STEERING MECHANISM SHOULD KEEP THE THREAT ISOLATED. HAVE ADDED A LOW
SEVERE PROBABILITY TO REFLECT THIS.
...CNTRL HI PLNS...
PATTERN WILL ONCE AGAIN FAVOR DEVELOPMENT OF ISOLD TO SCTD AFTN
TSTMS INVOF LEE TROUGH AND HIGHER TERRAIN OF ERN CO AND WY...GIVEN
MOIST SSELY LOW LVL FLOW BENEATH MODEST /15-25 KT/ NNW MID LVL JET.
LARGE SCALE FORCING FOR ASCENT APPEARS WEAKER THAN ON SUNDAY...WITH
NO SHORTWAVE DISTURBANCE OF NOTE APPARENT IN WV IMAGERY.
NEVERTHELESS...THE STORMS SHOULD GRADUALLY MOVE/DEVELOP SEWD INTO
UNSTABLE AIR /SBCAPE TO 2000 J PER KG/ OVER THE CNTRL HI PLNS
THROUGH EARLY EVE. DESPITE MODEST MID TROPOSPHERIC FLOW...LARGE
DIRECTIONAL COMPONENT IN THE WIND PROFILES /120-150 DEGREES IN THE
LOWEST 6 KM/ AND 30 KT DEEP NNWLY SHEAR SHOULD ONCE AGAIN SUPPORT
ORGANIZED MULTICELLS/BRIEF SUPERCELLS WITH LARGE HAIL...LOCALLY DMGG
WIND...AND POSSIBLY A BRIEF TORNADO.
..HALES/CROSBIE.. 08/25/2008
CLICK TO GET WUUS01 PTSDY1 PRODUCT
NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 2000Z
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