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WWUS20 KWNS 171648

SEL8

SPC WW 171648

ALZ000-FLZ000-GAZ000-CWZ000-180000-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 488

NWS STORM PREDICTION CENTER NORMAN OK

1250 PM EDT TUE JUL 17 2012



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       FAR SOUTHEAST ALABAMA

       NORTHERN FLORIDA INCLUDING THE PANHANDLE

       SOUTHERN GEORGIA

       COASTAL WATERS



EFFECTIVE THIS TUESDAY AFTERNOON AND EVENING FROM 1250 PM UNTIL

800 PM EDT.



HAIL TO 1 INCH 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 80

STATUTE MILES EAST AND WEST OF A LINE FROM 30 MILES EAST OF

APALACHICOLA FLORIDA TO 60 MILES NORTHEAST OF ALBANY GEORGIA.

FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH

OUTLINE UPDATE (WOUS64 KWNS WOU8).



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...TSTMS ARE RAPIDLY DEVELOPING THIS AFTERNOON AHEAD OF A

WEAK SURFACE LOW AND ALONG A LEE TROUGH WITHIN A THERMODYNAMIC

ENVIRONMENT FEATURING MLCAPE VALUES OF 3000+ J/KG.  WHILE VERTICAL

SHEAR WILL REMAIN WEAK ACROSS THE REGION...HIGH MOISTURE CONTENT

WILL FOSTER INTENSE WET MICROBURSTS CAPABLE OF DAMAGING WINDS.  SOME

HAIL IS ALSO POSSIBLE.



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

TO 1 INCH. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60 KNOTS.

A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 550. MEAN STORM MOTION

VECTOR 36010.





...MEAD

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