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URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 253

NWS STORM PREDICTION CENTER NORMAN OK

600 PM CDT MON MAY 7 2007



THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF



       SOUTH TEXAS



EFFECTIVE THIS MONDAY NIGHT AND TUESDAY MORNING FROM 600 PM UNTIL

200 AM CDT.



TORNADOES...HAIL TO 3 INCHES IN DIAMETER...THUNDERSTORM WIND

GUSTS TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE

AREAS.



THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 80 STATUTE

MILES EITHER SIDE OF A LINE FROM 5 MILES EAST NORTHEAST OF HONDO

TEXAS TO 50 MILES SOUTH SOUTHEAST OF DEL RIO TEXAS.  FOR A

COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE

UPDATE (WOUS64 KWNS WOU3).



REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR

TORNADOES AND 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.



DISCUSSION...SUPERCELLS AND SUPERCELL CLUSTERS THAT FORMED IN THE

HIGHER TERRAIN W OF THE RIO GRANDE EXPECTED TO MOVE/DEVELOP SLOWLY E

INTO 20+ KT CURRENT OF VERY MOIST ESELY LOW LEVEL FLOW.  WHILE DEEP

SHEAR IS MARGINAL FOR SUPERCELL DEVELOPMENT IN LOWER TERRAIN GIVEN

CIN... STRONGLY BACK LOW LEVEL WINDS SUGGEST TORNADO POTENTIAL WITH

ANY STORMS THAT DO MOVE/DEVELOP E INTO THIS ENVIRONMENT.



AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL

SURFACE AND ALOFT TO 3 INCHES. EXTREME TURBULENCE AND SURFACE

WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO

600. MEAN STORM MOTION VECTOR 26015.





...CORFIDI

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