

912 

WWUS20 KWNS 060905

SEL1

SPC WW 060905

ALZ000-GAZ000-061500-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 251

NWS STORM PREDICTION CENTER NORMAN OK

405 AM CDT WED MAY 6 2009



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       NORTHERN ALABAMA

       NORTHWEST GEORGIA



EFFECTIVE THIS WEDNESDAY MORNING FROM 405 AM UNTIL 1000 AM CDT.



HAIL TO 1.5 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70

MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.



THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 55

STATUTE MILES NORTH AND SOUTH OF A LINE FROM 50 MILES SOUTHWEST

OF MUSCLE SHOALS ALABAMA TO 30 MILES SOUTH OF ROME GEORGIA.  FOR

A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH

OUTLINE UPDATE (WOUS64 KWNS WOU1).



REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE

FAVORABLE FOR SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH

AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR

THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS

AND POSSIBLE WARNINGS. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY

DO PRODUCE TORNADOES.



OTHER WATCH INFORMATION...CONTINUE...WW 248...WW 249...WW 250...



DISCUSSION...THUNDERSTORMS WILL INCREASE WITHIN WAA REGIME ALONG AND

NORTH OF SURFACE WARM FRONT FROM NRN AL INTO NWRN GA EARLY THIS

MORNING.  AIR MASS IS MODERATELY UNSTABLE WITHIN WARM SECTOR AND WW

LIES WITHIN 40-50 KT EFFECTIVE SHEAR...SUPPORTIVE OF SUPERCELLS.

LARGE HAIL IS PRIMARY CONCERN WITH THESE INITIAL STORMS.  ADDITIONAL

THREAT IS EXPECTED TO MOVE ESEWD ACROSS WW BEGINNING AROUND DAYBREAK

AS POSSIBLE BOWING MCS MOVES ALONG SURFACE WARM FRONT.  THIS

ACTIVITY SHOULD BRING ENHANCED THREAT OF DAMAGING WINDS ACROSS NRN

AND PARTS OF CENTRAL AL THROUGH THE MID MORNING...AND POSSIBLY BEGIN

IMPACTING NRN/WRN GA THEREAFTER.



AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT

TO 1.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60

KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM

MOTION VECTOR 27035.





...EVANS

