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URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 282

NWS STORM PREDICTION CENTER NORMAN OK

355 PM CDT SAT MAY 19 2012



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       WESTERN AND NORTH CENTRAL OKLAHOMA



EFFECTIVE THIS SATURDAY AFTERNOON AND EVENING FROM 355 PM UNTIL

1000 PM CDT.



HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 75

MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.



THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 60

STATUTE MILES EAST AND WEST OF A LINE FROM 40 MILES EAST

NORTHEAST OF ALVA OKLAHOMA TO CLINTON 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...CONTINUE...WW 281...



DISCUSSION...VISIBLE IMAGERY SHOWS TCU DEVELOPING ALONG THE COLD

FRONT/DRY LINE OVER NWRN OK INTO THE EXTREME ERN TX PANHANDLE.  THIS

IS A LIKELY PRECURSOR TO THUNDERSTORM INITIATION WHICH IS EXPECTED

TO OCCUR WITHIN THE NEXT 1-2 HRS. THE ENVIRONMENT IS CHARACTERIZED

BY STEEP LAPSE RATES...MODERATE INSTABILITY WITH MLCAPE OF 1500-2000

J/KG...AND A RELATIVELY DEEP WELL-MIXED PBL.  THIS WILL FAVOR

PRODUCTION OF LARGE HAIL AND DAMAGING WIND GUSTS WITH STRONGER

CELLS.  ACTIVITY IS EXPECTED TO MOVE GENERALLY EWD WITH TIME

ALTHOUGH SOME SEWD MOTION MAY DEVELOP IF AN ORGANIZED COLD POOL IS

ABLE TO BE GENERATED.



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

TO 2 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 65

KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM

MOTION VECTOR 24020.





...WEISS

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