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URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 184

NWS STORM PREDICTION CENTER NORMAN OK

1135 PM CDT FRI APR 22 2011



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       PART OF SOUTHERN AND CENTRAL OKLAHOMA



EFFECTIVE THIS FRIDAY NIGHT AND SATURDAY MORNING FROM 1135 PM

UNTIL 600 AM 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 35

STATUTE MILES NORTH AND SOUTH OF A LINE FROM 5 MILES NORTHEAST OF

POTEAU OKLAHOMA TO 40 MILES SOUTH SOUTHWEST OF CHICKASHA

OKLAHOMA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE

ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU4).



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

TORNADO WATCH NUMBER 180. WATCH NUMBER 180 WILL NOT BE IN EFFECT

AFTER 1135 PM CDT. CONTINUE...WW 181...WW 182...WW 183...



DISCUSSION...SEVERE THUNDERSTORMS CONTINUE TO REDEVELOP ACROSS SRN

OK IN A WARM ADVECTION PATTERN WHERE THE AIR MASS IS UNSTABLE WITH

STEEP MID LEVEL LAPSE RATES.  LARGE HAIL WILL BE THE PRIMARY THREAT

WITH THE STRONGEST CORES INCLUDING ROTATING STORMS GIVEN THE 40-50KT

OF DEEP LAYER SHEAR.



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 24025.





...HALES

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