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WWUS20 KWNS 202100

SEL6

SPC WW 202100

NMZ000-OKZ000-TXZ000-210400-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 586

NWS STORM PREDICTION CENTER NORMAN OK

300 PM MDT MON AUG 20 2012



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       EASTERN NEW MEXICO

       WESTERN OKLAHOMA PANHANDLE

       WESTERN TEXAS



EFFECTIVE THIS MONDAY AFTERNOON AND EVENING FROM 300 PM UNTIL

1000 PM MDT.



HAIL TO 1.5 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70

MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.



THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 75

STATUTE MILES EAST AND WEST OF A LINE FROM 40 MILES NORTH OF

CLAYTON NEW MEXICO TO 20 MILES WEST SOUTHWEST OF HOBBS NEW

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

WATCH OUTLINE UPDATE (WOUS64 KWNS WOU6).



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.



DISCUSSION...TSTMS ARE EXPECTED TO INCREASE IN COVERAGE AND

INTENSITY THIS AFTERNOON INTO EVENING AS REGION IS INFLUENCED BY

WEAK MIDLEVEL PERTURBATION MOVING THROUGH THE CNTRL/SRN ROCKIES.

AMBIENT ENVIRONMENT IS CHARACTERIZED BY MLCAPE OF 1000-1500

J/KG...VERTICALLY VEERING WIND PROFILES AND STEADILY STRENGTHENING

DEEP-LAYER SHEAR.  AS SUCH...SETUP WILL FAVOR SOME SUPERCELL

STRUCTURES AS THE INITIAL STORM MODE WITH A RISK FOR LARGE HAIL.

GROWING STORM-SCALE COLD POOLS AND AN INTENSIFYING NOCTURNAL

LOW-LEVEL JET MAY SUPPORT UPSCALE GROWTH OF STORMS TO A SEWD-MOVING

MCS CAPABLE OF DAMAGING WINDS LATER THIS EVENING.



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

TO 1.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60

KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM

MOTION VECTOR 33025.





...MEAD

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