

525 

WWUS20 KWNS 122251

SEL3

SPC WW 122251

TNZ000-130500-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 393

NWS STORM PREDICTION CENTER NORMAN OK

550 PM CDT FRI JUN 12 2009



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       SOUTHERN MIDDLE TENNESSEE



EFFECTIVE THIS FRIDAY AFTERNOON FROM 550 PM UNTIL MIDNIGHT 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 100

STATUTE MILES EAST AND WEST OF A LINE FROM 65 MILES EAST

NORTHEAST OF JACKSON TENNESSEE TO 95 MILES WEST OF CHATTANOOGA

TENNESSEE.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE

ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU3).



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 388...WW 389...WW

390...WW 391...WW 392...



DISCUSSION...NRN PART OF LONG-LIVED DERECHO-PRODUCING MCS WILL

GLANCE SRN MIDDLE TN THIS EVE.  MCS WILL CONTINUE TO MERGE WITH

INDEPENDENT STORMS AHEAD OF IT.  IN ADDITION...WEAK SFC BOUNDARY

WITH LESS UNSTABLE AIR MASS TO ITS N WILL PERSIST ACROSS NRN MS/AL.

THESE FACTORS CAST SOME UNCERTAINTY AS TO HOW FAR N SVR THREAT WILL

EXTEND INTO MIDDLE TN.  NEVERTHELESS...A CONDITIONAL THREAT FOR HIGH

WIND/HAIL WILL EXIST WITH ANY STRONGER STORMS THAT REMAIN/DEVELOP N

OF THE TN BORDER UNTIL LATER THIS EVE.



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 28035.





...CORFIDI

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