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478 

WWUS20 KWNS 212326

SEL9

SPC WW 212326

TXZ000-220700-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 339

NWS STORM PREDICTION CENTER NORMAN OK

625 PM CDT FRI JUN 21 2013



THE NWS STORM PREDICTION CENTER HAS ISSUED A



* SEVERE THUNDERSTORM WATCH FOR PORTIONS OF

  WEST TEXAS



* EFFECTIVE THIS FRIDAY NIGHT AND SATURDAY MORNING FROM 625 PM

  UNTIL 200 AM CDT.



* PRIMARY THREATS INCLUDE...

  A FEW SIGNIFICANT DAMAGING WIND GUSTS TO 75 MPH POSSIBLE

  A FEW VERY LARGE HAIL EVENTS TO 2 INCHES IN DIAMETER POSSIBLE



THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 55

STATUTE MILES EAST AND WEST OF A LINE FROM 30 MILES NORTH

NORTHWEST OF AMARILLO TEXAS TO 60 MILES SOUTHWEST OF DRYDEN

TEXAS.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED

WATCH OUTLINE UPDATE (WOUS64 KWNS WOU9).



PRECAUTIONARY/PREPAREDNESS ACTIONS...



REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE

FAVORABLE FOR 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. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY

DO PRODUCE TORNADOES.



&&



OTHER WATCH INFORMATION...CONTINUE...WW 336...WW 337...WW 338...



DISCUSSION...SO FAR...ONLY ISOLATED STORMS EXIST NEAR THE TX/NM

BORDER AND ACROSS FAR WEST TX/BIG BEND AREA. AIRMASS TO THE EAST OF

THE ONGOING STORMS IS MODERATELY UNSTABLE AND LARGE SCALE ASCENT MAY

BE ENHANCED THROUGH THE EVENING AS A SRN STREAM DISTURBANCE SPREADS

EAST FROM NM. A WELL-MIXED BOUNDARY LAYER AND ADEQUATE SHEAR THROUGH

THE CLOUD-BEARING LAYER SHOULD SUPPORT SUPERCELL STORMS WITH BOTH

LARGE HAIL AND HIGH WIND THREATS. OVERALL STORM COVERAGE MAY REMAIN

QUITE SCATTERED BUT JUST ABOUT ANY CONVECTION WILL BE CAPABLE OF

SEVERE WEATHER GIVEN SUPPORTIVE ENVIRONMENTAL PARAMETERS.



AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT

TO 2 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 65

KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 550. MEAN STORM

MOTION VECTOR 27020.





...CARBIN

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