

246 

WWUS20 KWNS 251909

SEL3

SPC WW 251909

TXZ000-260200-



URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 63

NWS STORM PREDICTION CENTER NORMAN OK

205 PM CDT WED MAR 25 2009



THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF



       CENTRAL AND SOUTHEAST TEXAS



EFFECTIVE THIS WEDNESDAY AFTERNOON AND EVENING FROM 205 PM UNTIL

900 PM CDT.



TORNADOES...HAIL TO 2.5 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 55 STATUTE

MILES NORTH AND SOUTH OF A LINE FROM 30 MILES NORTH OF DEL RIO

TEXAS TO 30 MILES EAST NORTHEAST OF HUNTSVILLE 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.



OTHER WATCH INFORMATION...CONTINUE...WW 62...



DISCUSSION...SURFACE-BASED THUNDERSTORMS ARE BEGINNING TO DEVELOP

ALONG THE NW EDGE OF THE SURFACE WARM SECTOR BETWEEN DRT AND SJT.

THESE STORMS WILL LIKELY INCREASE IN COVERAGE/INTENSITY THROUGH THE

AFTERNOON AS A MID LEVEL SPEED MAX EJECTS EWD FROM THE BIG

BEND...AND A SURFACE WARM FRONT LIFTS SLOWLY NWD ACROSS S CENTRAL

AND SE TX.  MODERATE INSTABILITY /MLCAPE AOA 1500 J/KG/ AND

EFFECTIVE BULK SHEAR IN EXCESS OF 50 KT WILL FAVOR SUPERCELLS

CAPABLE OF PRODUCING VERY LARGE HAIL AND DAMAGING WINDS.  LOW-LEVEL

FLOW/SHEAR WILL GRADUALLY INCREASE THROUGH THE AFTERNOON ACROSS

CENTRAL/SE TX IN ADVANCE OF THE EJECTING MID LEVEL SPEED MAX...THUS

SUPPORTING A THREAT FOR TORNADOES WITH STORMS ALONG THE WARM FRONT.



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

SURFACE AND ALOFT TO 2.5 INCHES. EXTREME TURBULENCE AND SURFACE

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

500. MEAN STORM MOTION VECTOR 26030.





...THOMPSON

