

578 

WWUS20 KWNS 090449

SEL8

SPC WW 090449

TXZ000-091000-



URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 278

NWS STORM PREDICTION CENTER NORMAN OK

1150 PM CDT FRI MAY 8 2009



THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF



       NORTH TEXAS



EFFECTIVE THIS FRIDAY NIGHT AND SATURDAY MORNING FROM 1150 PM

UNTIL 500 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 95 STATUTE

MILES EAST AND WEST OF A LINE FROM 20 MILES NORTHEAST OF SHERMAN

TEXAS TO 55 MILES WEST SOUTHWEST OF TYLER TEXAS.  FOR A COMPLETE

DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE UPDATE

(WOUS64 KWNS WOU8).



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...THIS TORNADO WATCH REPLACES TORNADO

WATCH NUMBER 272. WATCH NUMBER 272 WILL NOT BE IN EFFECT AFTER

1150 PM CDT. CONTINUE...WW 273...WW 274...WW 276...WW 277...



DISCUSSION...SCTD...INTENSE SUSTAINED STORMS/SUPERCELLS EXPECTED TO

PERSIST THROUGH EARLY SAT IN AREA OF VERY MOIST AIR BENEATH DEEP

EML.  COMBINATION OF STRONGER-THAN-PROGGED LLJ AND PRESENCE OF

EXISTING INTENSE UPDRAFTS SUGGEST A CONTINUED THREAT FOR VERY LARGE

HAIL/LOCALLY DMGG WIND...AND PERHAPS ISOLD TORNADOES AS STORMS

CONTINUE TO INTERACT AND PERHAPS GRADUALLY EVOLVE INTO A

SMALL...FORWARD-PROPAGATING MCS.



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

550. MEAN STORM MOTION VECTOR 32025.





...CORFIDI

