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505 

WWUS20 KWNS 082235

SEL8

SPC WW 082235

ARZ000-MOZ000-OKZ000-090500-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 488

NWS STORM PREDICTION CENTER NORMAN OK

535 PM CDT THU AUG 8 2013



THE NWS STORM PREDICTION CENTER HAS ISSUED A



* SEVERE THUNDERSTORM WATCH FOR PORTIONS OF

  NORTHERN AND CENTRAL ARKANSAS

  THE BOOTHEEL OF MISSOURI

  PARTS OF EASTERN OKLAHOMA



* EFFECTIVE THIS THURSDAY AFTERNOON FROM 535 PM UNTIL MIDNIGHT

  CDT.



* PRIMARY THREATS INCLUDE...

  SEVERAL LARGE HAIL EVENTS WITH A FEW VERY LARGE HAIL EVENTS TO 2

    INCHES IN DIAMETER POSSIBLE

  SEVERAL DAMAGING WIND GUSTS TO 70 MPH POSSIBLE



THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 65

STATUTE MILES NORTH AND SOUTH OF A LINE FROM 50 MILES NORTHWEST

OF MCALESTER OKLAHOMA TO 35 MILES SOUTHEAST OF JONESBORO

ARKANSAS.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE

ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU8).



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 487...



DISCUSSION...THUNDERSTORMS HAVE BEGUN DEVELOPING THIS AFTERNOON

WITHIN A MOIST/VERY UNSTABLE ENVIRONMENT NEAR AND N OF A WEAK

SURFACE BOUNDARY EXTENDING WEST-TO-EAST ACROSS OKLAHOMA AND

ARKANSAS.  WITH SLY/SELY LOW-LEVEL FLOW VEERING WITH HEIGHT TO

AROUND 30 KT FROM THE WEST AT MID LEVELS...SHEAR IS SUFFICIENT --

GIVEN DEGREE OF OBSERVED CAPE -- TO SUPPORT ORGANIZED/SEVERE STORMS.

EXPECT LARGE HAIL TO BE THE MAIN THREAT INITIALLY...THOUGH POTENTIAL

FOR WIND DAMAGE MAY INCREASE OVER THE NEXT COUPLE OF HOURS GIVEN THE

POSSIBILITY FOR STORMS TO GROW UPSCALE INTO SMALL BOWING CLUSTERS.



AVIATION...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 26030.





...GOSS

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