661 WWUS20 KWNS 211913 SEL9 SPC WW 211908 ILZ000-MOZ000-212300- URGENT - IMMEDIATE BROADCAST REQUESTED TORNADO WATCH NUMBER 139 STORM PREDICTION CENTER NORMAN OK 208 PM CDT SUN APR 21 2002 THE STORM PREDICTION CENTER HAS ISSUED A TORNADO WATCH FOR PORTIONS OF SOUTHERN ILLINOIS SOUTHEASTERN MISSOURI EFFECTIVE THIS SUNDAY AFTERNOON AND EVENING FROM 215 PM UNTIL 600 PM CDT. TORNADOES...HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS. THE TORNADO WATCH AREA IS ALONG AND 70 STATUTE MILES EAST AND WEST OF A LINE FROM 30 MILES SOUTHEAST OF POPLAR BLUFF MISSOURI TO 15 MILES WEST NORTHWEST OF MATTOON ILLINOIS. 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...THIS TORNADO WATCH REPLACES SEVERE THUNDERSTORM WATCH NUMBER 136. WATCH NUMBER 136 WILL NOT BE IN EFFECT AFTER 215 PM CDT. CONTINUE...WW 137...WW 138... DISCUSSION...INCREASING TORNADO THREAT DEVELOPING NEAR AND NORTH OF OUTFLOW BOUNDARY ACROSS CENTRAL IL...WHERE SURFACE LOW WILL LIKELY TRACK. SUPERCELLS WILL ALSO LIKELY DEVELOP SWD ALONG APPROACHING COLD FRONT INTO SRN IL. AVIATION...TORNADOES AND 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 500. MEAN STORM MOTION VECTOR 26040. ...EVANS ;362,0912 393,0895 393,0871 362,0884; 489 WWUS20 KWNS 211913 SEL9 SPC WW 211908 ILZ000-MOZ000-212300-