

990 

WWUS20 KWNS 041726

SEL5

SPC WW 041726

ARZ000-MOZ000-OKZ000-050100-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 545

NWS STORM PREDICTION CENTER NORMAN OK

1230 PM CDT SAT JUL 4 2009



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       NORTHERN ARKANSAS

       EXTREME SOUTHERN MISSOURI

       EASTERN OKLAHOMA



EFFECTIVE THIS SATURDAY AFTERNOON AND EVENING FROM 1230 PM UNTIL

800 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 45

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

SOUTHWEST OF MUSKOGEE OKLAHOMA TO 25 MILES NORTH OF WALNUT RIDGE

ARKANSAS.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE

ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU5).



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...THUNDERSTORMS SHOULD CONTINUE TO INTENSIFY ALONG EWD

TRACKING MCS OUTFLOW MOVING INTO HOT/UNSTABLE AIRMASS FROM ERN OK

ACROSS NRN AR THIS AFTERNOON. DESPITE LIMITED MID-LEVEL

FLOW...SUFFICIENT LIFT ALONG LEADING EDGE OF COLD POOL...AND

STEEPENING LOW-LEVEL LAPSE RATES SHOULD CONTRIBUTE TO DAMAGING WIND

POTENTIAL AS STORMS MOVE/DEVELOP EAST THROUGH THE AFTERNOON.



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 28015.





...CARBIN

