

000 

WWUS20 KWNS 301955

SEL9

SPC WW 301955

ARZ000-MOZ000-OKZ000-010200-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 699

NWS STORM PREDICTION CENTER NORMAN OK

255 PM CDT SUN SEP 30 2007



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       NORTHWEST ARKANSAS

       SOUTHWEST MISSOURI

       NORTHEAST OKLAHOMA



EFFECTIVE THIS SUNDAY AFTERNOON AND EVENING FROM 255 PM UNTIL 900

PM CDT.



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 115

STATUTE MILES EAST AND WEST OF A LINE FROM 25 MILES NORTH

NORTHWEST OF GROVE OKLAHOMA TO 25 MILES WEST OF MUSKOGEE

OKLAHOMA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE

ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU9).



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 697...WW 698...



DISCUSSION...STRONG COLD FRONT WILL SURGE INTO INCREASINGLY UNSTABLE

AIR MASS ACROSS THE REGION THROUGH THE EVENING. FORCED ASCENT ALONG

THE FRONT SHOULD SPUR RAPID AND LOCALLY INTENSE STORMS WITH

STRENGTHENING MEAN LAYER FLOW OF UP TO 50KT SUPPORTING RAPID STORM

MOTION. SOME POTENTIAL ALSO EXISTS FOR SUPERCELLS NEAR ANY BREAKS IN

THE CONVECTIVE LINE. HIGH/DAMAGING WINDS APPEAR TO BE THE PRIMARY

THREAT WITH SECONDARY HAZARD BEING ISOLATED LARGE HAIL.



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 450. MEAN STORM

MOTION VECTOR 26035.





...CARBIN

