

826 

WWUS20 KWNS 281733

SEL0

SPC WW 281733

ALZ000-GAZ000-TNZ000-290100-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 530

NWS STORM PREDICTION CENTER NORMAN OK

135 PM EDT SUN JUN 28 2009



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       NORTHERN AND CENTRAL ALABAMA

       WESTERN AND CENTRAL GEORGIA

       SOUTHEAST TENNESSEE



EFFECTIVE THIS SUNDAY AFTERNOON AND EVENING FROM 135 PM UNTIL 900

PM EDT.



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 135

STATUTE MILES EAST AND WEST OF A LINE FROM 50 MILES SOUTH

SOUTHWEST OF COLUMBUS GEORGIA TO 55 MILES NORTHEAST OF HUNTSVILLE

ALABAMA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE

ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU0).



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.



DISCUSSION...THUNDERSTORMS ARE BEGINNING TO FORM ACROSS PARTS OF

TN/AL/GA IN AXIS OF VERY MOIST AND UNSTABLE AIR.  PWAT VALUES OVER 2

INCHES...MLCAPE OF 3000+ J/KG AND ABOUT 20 KNOTS OF EFFECTIVE SHEAR

WILL PROMOTE SLOW-MOVING MULTICELL STORM CLUSTERS CAPABLE OF WET

MICROBURSTS.



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 32020.





...HART

