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URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 200

NWS STORM PREDICTION CENTER NORMAN OK

635 PM CDT SAT APR 28 2012



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       WESTERN AND CENTRAL OKLAHOMA

       THE TEXAS SOUTH PLAINS AND WESTERN NORTH TEXAS



EFFECTIVE THIS SATURDAY NIGHT AND SUNDAY MORNING FROM 635 PM

UNTIL 200 AM CDT.



HAIL TO 3 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 50

STATUTE MILES EAST AND WEST OF A LINE FROM 55 MILES WEST

SOUTHWEST OF ABILENE TEXAS TO 10 MILES EAST NORTHEAST OF ENID

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 197...WW 198...WW 199...



DISCUSSION...TSTMS/SUPERCELLS EXPECTED TO FORM NEAR SW-NE

DRYLINE/FRONT MOVING NWWD ACROSS W CNTRL TX AND SW/CNTRL OK.

ACTIVITY WILL BE SUPPORTED BY WEAKENING OF EXISTING EML CAP

FOLLOWING DAYTIME HEATING...CONTINUED LOW LVL MOISTURE INFLOW...AND

INCREASING ASCENT ASSOCIATED WITH ENTRANCE REGION OF JET STREAM

CROSSING NM.  MAIN SVR THREAT SHOULD BE LARGE HAIL...ESPECIALLY FROM

POSSIBLE LEFT SPLIT STORMS ALONG WRN FRINGE OF WW.  SETUP ALSO MAY

SUPPORT A CONDITIONAL RISK FOR TORNADOES...MAINLY IN WRN N TX AND SW

OK...WHERE LOW LVL FLOW WILL REMAIN SLIGHTLY BACKED N OF NW TX SFC

WAVE AS LLJ STRENGTHENS THIS EVE.  DEPENDING UPON PREDOMINANT STORM

MODE/PATTERN OF DEVELOPMENT...THIS REGION MAY REQUIRE UPGRADE TO A

TORNADO WW LATER TNGT.  OTHERWISE...EXPECT EVENTUAL DEVELOPMENT OF

ONE OR MORE STORM COMPLEXES...WITH STORM INTERACTIONS/

FORWARD-PROPAGATING SEGMENTS EXTENDING THE SVR THREAT GENERALLY E/NE

WITH TIME.



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

TO 3 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60

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

MOTION VECTOR 27020.





...CORFIDI

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