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URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 430

NWS STORM PREDICTION CENTER NORMAN OK

1045 AM CDT WED JUN 30 2010



THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF



       THE LOWER AND MIDDLE TEXAS COAST

       COASTAL WATERS



EFFECTIVE THIS WEDNESDAY MORNING AND EVENING FROM 1045 AM UNTIL

800 PM CDT.



TORNADOES...HAIL TO 0.5 INCH IN DIAMETER...THUNDERSTORM WIND

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

AREAS.



THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 45 STATUTE

MILES EAST AND WEST OF A LINE FROM 35 MILES NORTHEAST OF CORPUS

CHRISTI TEXAS TO 40 MILES EAST SOUTHEAST OF MCALLEN TEXAS.  FOR A

COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE

UPDATE (WOUS64 KWNS WOU0).



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...HURRICANE ALEX CONTINUES TO MOVE TOWARD EXTREME NE

MEXICO...LEAVING S TX IN THE RIGHT FRONT QUADRANT OF THE STORM

CIRCULATION.  LOCAL VWP/S HAVE SHOWN AN INCREASE IN LOW-LEVEL

FLOW/SHEAR OVER THE PAST FEW HOURS...AND EMBEDDED SUPERCELL

STRUCTURES ARE TENDING TO SURVIVE CLOSER TO THE COAST WITH TIME IN

THE BANDS N OF THE STORM CENTER.  GIVEN THE PRESENCE OF 77-80 F

DEWPOINTS...SURFACE-BASED INSTABILITY...AND INCREASING VERTICAL

SHEAR...THE PROBABILITY OF A FEW TORNADOES WILL SLOWLY INCREASE

THROUGH THE AFTERNOON.



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

SURFACE AND ALOFT TO 0.5 INCH. EXTREME TURBULENCE AND SURFACE

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

550. MEAN STORM MOTION VECTOR 09035.





...THOMPSON

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