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886 

WWUS20 KWNS 140141

SEL3

SPC WW 140141

OKZ000-140900-



URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 163

NWS STORM PREDICTION CENTER NORMAN OK

835 PM CDT FRI APR 13 2012



THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF



       WESTERN AND CENTRAL OKLAHOMA



EFFECTIVE THIS FRIDAY NIGHT AND SATURDAY MORNING FROM 835 PM

UNTIL 400 AM CDT.



TORNADOES...HAIL TO 2.5 INCHES IN DIAMETER...THUNDERSTORM WIND

GUSTS TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE

AREAS.



THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 75 STATUTE

MILES NORTH AND SOUTH OF A LINE FROM 45 MILES WEST NORTHWEST OF

CLINTON OKLAHOMA TO 40 MILES EAST NORTHEAST OF CHANDLER OKLAHOMA.

 FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH

OUTLINE UPDATE (WOUS64 KWNS WOU3).



REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR

TORNADOES AND 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.



OTHER WATCH INFORMATION...CONTINUE...WW 160...WW 161...WW 162...



DISCUSSION...CLUSTER OF SUPERCELLS WITH A HISTORY OF TORNADOES OVER

SWRN OK /FROM W LTS TO NW FSI/ IS EXPECTED TO TRACK ENEWD ALONG

OUTFLOW BOUNDARY INTO CNTRL OK LATER TONIGHT.  CURRENT VAD

OBSERVATIONS FROM FREDRICK OK AND TWIN LAKES OK INDICATE NOTABLE

STRENGTHENING OF THE LLJ OVER THE PAST HOUR WITH 0-1 KM SRH OF

300-400 M2/S2.  TORNADO THREAT WILL BE DICTATED BY ABILITY OF STORMS

TO MANAGE CONVECTIVE OUTFLOW...THOUGH SIGNIFICANT TORNADOES ARE

POSSIBLE GIVEN THE STRONG LOW-LEVEL SHEAR.  ELSEWHERE...A SECONDARY

CORRIDOR OF TORNADO POTENTIAL WILL EXIST TONIGHT ACROSS PORTIONS OF

NRN OK WHERE LOW-LEVEL SHEAR AND MOISTURE ARE INCREASING WITHIN A

BOUNDARY LAYER THAT WAS NOT OVERTURNED BY EARLIER CONVECTION.



AVIATION...TORNADOES AND 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

500. MEAN STORM MOTION VECTOR 24020.





...MEAD

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