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URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 479

NWS STORM PREDICTION CENTER NORMAN OK

155 PM EDT WED JUN 15 2011



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       CENTRAL AND SOUTH FLORIDA

       COASTAL WATERS



EFFECTIVE THIS WEDNESDAY AFTERNOON AND EVENING FROM 155 PM UNTIL

800 PM EDT.



HAIL TO 2 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 65

STATUTE MILES EAST AND WEST OF A LINE FROM 15 MILES EAST OF OCALA

FLORIDA TO 45 MILES WEST SOUTHWEST OF MIAMI FLORIDA.  FOR A

COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE

UPDATE (WOUS64 KWNS WOU9).



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 478...



DISCUSSION...THUNDERSTORMS ARE BEGINNING TO DEVELOP ALONG SUBTLE

CONFLUENCE BANDS ACROSS CENTRAL/N FL...WHILE ADDITIONAL SEA BREEZE

DEVELOPMENT IS LIKELY IN THE NEXT 1-2 HOURS.  MLCAPE UP TO 4000 J/KG

IS PRESENT ACROSS CENTRAL/S FL...AND NLY MIDLEVEL FLOW WILL HELP

STEER CONVECTION SWD/SWWD INTO THE CORRIDOR OF STRONG INSTABILITY

THROUGH THE AFTERNOON.  THERMODYNAMIC PROFILES WILL FAVOR WET

MICROBURSTS WITH DAMAGING WINDS...AS WELL AS THE POTENTIAL FOR LARGE

HAIL WITH THE MORE INTENSE UPDRAFTS.



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

TO 2 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60

KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 600. MEAN STORM

MOTION VECTOR 36020.





...THOMPSON

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