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URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 135

NWS STORM PREDICTION CENTER NORMAN OK

235 PM CDT TUE APR 3 2012



THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF



       FAR SOUTHWEST ARKANSAS

       NORTHWEST LOUISIANA

       EASTERN TEXAS



EFFECTIVE THIS TUESDAY AFTERNOON AND EVENING FROM 235 PM UNTIL

1000 PM CDT.



TORNADOES...HAIL TO 2 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 65 STATUTE

MILES EAST AND WEST OF A LINE FROM 75 MILES NORTH NORTHWEST OF

SHREVEPORT LOUISIANA TO 25 MILES SOUTHWEST OF LUFKIN TEXAS.  FOR

A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH

OUTLINE UPDATE (WOUS64 KWNS WOU5).



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 132...WW 133...WW 134...



DISCUSSION...SEVERE STORMS IN PROGRESS OVER N-CNTRL TX ARE EXPECTED

TO MOVE/DEVELOP EWD ACROSS THE WATCH AREA THIS AFTERNOON INTO

EVENING IN ADVANCE OF MIDLEVEL VORTICITY MAXIMUM LIFTING NEWD

THROUGH THE RED RIVER VALLEY.  AMBIENT WARM SECTOR AIR MASS

/CHARACTERIZED BY MLCAPE OF 2000-2500 J PER KG/ WILL REMAIN BOUND ON

THE N BY AN W-E ORIENTED OUTFLOW BOUNDARY SITUATED JUST N OF THE

I-20 CORRIDOR.  BOTH LOW AND DEEP-LAYER SHEAR WILL STRENGTHEN WITH

THE EWD PROGRESSION OF THE VORTICITY MAXIMUM...RESULTING IN AN

ENVIRONMENT SUPPORTIVE OF SUPERCELLS.  THE GREATEST RISK FOR

TORNADOES WILL EXIST WITH STORMS INTERACTING WITH OUTFLOW BOUNDARY

WHERE LOW-LEVEL SHEAR/VORTICITY IS ENHANCED.  IN ADDITION TO THE

TORNADO THREAT...VERY LARGE HAIL WILL BE POSSIBLE AS WILL LOCALLY

DAMAGING STRAIGHT-LINE WINDS.



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

SURFACE AND ALOFT TO 2 INCHES. EXTREME TURBULENCE AND SURFACE

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

500. MEAN STORM MOTION VECTOR 22030.





...MEAD

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