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URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 42

NWS STORM PREDICTION CENTER NORMAN OK

620 AM CDT FRI APR 2 2010



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       PARTS OF CENTRAL AND EASTERN OKLAHOMA



EFFECTIVE THIS FRIDAY MORNING FROM 620 AM UNTIL 1000 AM 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 60

STATUTE MILES EAST AND WEST OF A LINE FROM 20 MILES EAST

NORTHEAST OF CHANDLER OKLAHOMA TO 30 MILES SOUTH SOUTHWEST OF

ARDMORE 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.



DISCUSSION...RAPIDLY MOVING STORMS ROOTED JUST ABOVE THE SURFACE

WILL LIKELY CONTINUE FOR A FEW HOURS ACROSS CENTRAL OK...IN ADVANCE

OF A REMNANT DRYLINE/COLD FRONT.  GIVEN THE HIGH MOMENTUM FLOW JUST

OFF THE GROUND AND AT LEAST WEAK SURFACE-BASED INSTABILITY...THERE

WILL BE A THREAT FOR DAMAGING WINDS WITH THE STRONGER EMBEDDED

BOWING SEGMENTS.  ALSO...STEEP MID LEVEL LAPSE RATES WILL SUPPORT

THE THREAT FOR LARGE HAIL WITH THE MORE INTENSE UPDRAFTS.



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 450. MEAN STORM

MOTION VECTOR 23055.





...THOMPSON

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