Tornado Watch from the Storm Prediction Center

URGENT - IMMEDIATE BROADCAST REQUESTED TORNADO WATCH NUMBER 108 NWS STORM PREDICTION CENTER NORMAN OK 535 PM CDT FRI APR 8 2011 THE NWS STORM PREDICTION CENTER HAS ISSUED A TORNADO WATCH FOR PORTIONS OF SOUTH CENTRAL INTO EAST CENTRAL KANSAS WESTERN AND NORTHERN OKLAHOMA EFFECTIVE THIS FRIDAY AFTERNOON AND SATURDAY MORNING FROM 535 PM UNTIL 100 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 65 STATUTE MILES NORTH AND SOUTH OF A LINE FROM 35 MILES NORTH OF CLINTON OKLAHOMA TO 25 MILES EAST NORTHEAST OF CHANUTE KANSAS. FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU8). 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 106...WW 107... DISCUSSION...TSTMS HAVE FORMED IN THE PAST HALF HOUR ALONG LOW-LVL CONFLUENCE AXIS OVER N CNTRL OK. TWRG CU EXTEND SSW FROM THAT AREA ALONG DRY LINE INTO SW OK. SFC-BASED CU ALSO ARE APPARENT ALONG W/E FRONT OVER S CNTRL/E CNTRL KS. DESPITE APPARENT RIDGING ALOFT /PER WV IMAGERY/...COMBINATION OF STRONG INSTABILITY AND LOW-LVL CONFLUENCE MAY SUPPORT SUSTAINED STORMS/POSSIBLE SUPERCELLS WITH LARGE HAIL/LOCALLY DMGG WIND THROUGH LATE EVE. WHILE LOW-LVL SHEAR ATTM IS SOMEWHAT MARGINAL FOR TORNADOES...EXPECTED STRENGTHENING OF 850-700 MB FLOW AFTER DARK INTERACTING WITH EXISTING SUSTAINED STORMS MAY YIELD A THREAT FOR TORNADOES. 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 550. MEAN STORM MOTION VECTOR 24025.