

681 

WWUS20 KWNS 100815

SEL2

SPC WW 100815

ARZ000-OKZ000-101300-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 762

NWS STORM PREDICTION CENTER NORMAN OK

315 AM CDT WED AUG 10 2011



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       NORTHWEST ARKANSAS

       EAST CENTRAL AND NORTHEAST OKLAHOMA



EFFECTIVE THIS WEDNESDAY MORNING FROM 315 AM UNTIL 800 AM CDT.



HAIL TO 1 INCH 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 65

STATUTE MILES EAST AND WEST OF A LINE FROM 35 MILES NORTH

NORTHEAST OF FAYETTEVILLE ARKANSAS TO 25 MILES SOUTH SOUTHWEST OF

POTEAU OKLAHOMA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE

ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU2).



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...THIS SEVERE THUNDERSTORM WATCH REPLACES

SEVERE THUNDERSTORM WATCH NUMBER 761. WATCH NUMBER 761 WILL NOT

BE IN EFFECT AFTER 315 AM CDT. CONTINUE...WW 759...WW 760...



DISCUSSION...BOWING MCS OVER NE OK SHOULD PERSIST FOR A FEW MORE

HOURS WHILE FORWARD PROPAGATING INTO LOW-LEVEL ELY FLOW ON THE COOL

SIDE OF A DIFFUSE BOUNDARY ACROSS AR.  DESPITE SUBSTANTIAL

CONVECTIVE INHIBITION...MUCAPE AOA 2000 J/KG REMAINS ALONG AND N OF

THIS BOUNDARY WHERE BOUNDARY LAYER DEWPOINTS ARE IN THE LOW

70S...WHILE VERTICAL SHEAR IS SUFFICIENT TO MAINTAIN AN ORGANIZED

CLUSTER CAPABLE OF PRODUCING DAMAGING WINDS.



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

TO 1 INCH. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60 KNOTS.

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

VECTOR 27040.





...THOMPSON

