

483 

WWUS20 KWNS 162135

SEL0

SPC WW 162135

OKZ000-TXZ000-170500-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 590

NWS STORM PREDICTION CENTER NORMAN OK

435 PM CDT THU JUL 16 2009



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       WESTERN AND CENTRAL OKLAHOMA

       EXTREME NORTHERN TEXAS



EFFECTIVE THIS THURSDAY AFTERNOON FROM 435 PM UNTIL MIDNIGHT CDT.



HAIL TO 2.5 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 85

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

NORTHEAST OF DURANT OKLAHOMA TO 40 MILES WEST OF CLINTON

OKLAHOMA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE

ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU0).



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 587...WW 588...WW 589...



DISCUSSION...THUNDERSTORMS CONTINUE TO DEVELOP AND INTENSIFY ALONG

SEVERAL REMNANT OUTFLOW BOUNDARIES OVER NRN AND SRN OKLAHOMA.

ENVIRONMENT IS VERY WARM ACROSS MUCH OF THE AREA WITH TEMPERATURES

OF 95-100F WHICH IS CONTRIBUTING MLCAPE OF 1500-2500 J/KG.  NWLY

FLOW ALOFT IS FORECAST TO STRENGTHEN THIS EVENING WHICH WILL ENHANCE

DEEP LAYER SHEAR AND AID IN STORM ORGANIZATION AND CONTINUED

POTENTIAL FOR SEVERE STORMS.



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

TO 2.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60

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

MOTION VECTOR 27025.





...WEISS

