URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 147
NWS STORM PREDICTION CENTER NORMAN OK
120 PM CDT WED APR 23 2003
THE NWS STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF
WESTERN AND NORTHWESTERN OKLAHOMA
EFFECTIVE THIS WEDNESDAY AFTERNOON AND EVENING FROM 120 PM UNTIL
700 PM CDT.
HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70
MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.
THE SEVERE THUNDERSTORM WATCH AREA IS ALONG AND 65 STATUTE MILES
EAST AND WEST OF A LINE FROM 60 MILES NORTHWEST OF ENID OKLAHOMA
TO 45 MILES SOUTH SOUTHEAST OF CLINTON OKLAHOMA.
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.
OTHER WATCH INFORMATION...CONTINUE...WW 146...
DISCUSSION...THE SURFACE DRYLINE IS SURGING EWD ACROSS THE ERN TX
PANHANDLE...AND A BAND OF STORMS HAS MOVED E OF THIS BOUNDARY BY
ABOUT A COUNTY. CLOUDS HAVE LIMITED DESTABILIZATION ACROSS WRN
OK...BUT CONTINUED MOISTURE ADVECTION FROM THE S/SE WILL ALLOW
SBCAPE VALUES TO INCREASE TO 500-1000 J/KG THIS AFTERNOON. EXPECT
THE LINE OF STORMS TO CONTINUE EWD...WITH AN INCREASING THREAT OF
DAMAGING WINDS AND LARGE HAIL. THOUGH VERTICAL SHEAR WILL BE
SUFFICIENT FOR SUPERCELLS...THE RELATIVELY WEAK INSTABILITY AND
LINEAR FORCING SUGGEST THAT THE SQUALL LINE SHOULD REMAIN THE MAIN
CONVECTIVE MODE ACROSS WRN OK.
AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
TO 2 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60
KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 450. MEAN STORM
MOTION VECTOR 25035.