WWUS20 KWNS 281927 SEL3 SPC WW 281927 IAZ000-KSZ000-MOZ000-NEZ000-290300- URGENT - IMMEDIATE BROADCAST REQUESTED TORNADO WATCH NUMBER 233 NWS STORM PREDICTION CENTER NORMAN OK 225 PM CDT TUE MAY 28 2013 THE NWS STORM PREDICTION CENTER HAS ISSUED A * TORNADO WATCH FOR PORTIONS OF SOUTHERN IOWA NORTHEAST KANSAS NORTHERN MISSOURI FAR SOUTHEAST NEBRASKA * EFFECTIVE THIS TUESDAY AFTERNOON AND EVENING FROM 225 PM UNTIL 1000 PM CDT. * PRIMARY THREATS INCLUDE... SEVERAL TORNADOES POSSIBLE SEVERAL VERY LARGE HAIL EVENTS TO 3 INCHES IN DIAMETER LIKELY SEVERAL DAMAGING WIND GUSTS TO 70 MPH POSSIBLE THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 80 STATUTE MILES NORTH AND SOUTH OF A LINE FROM 25 MILES SOUTH SOUTHWEST OF CONCORDIA KANSAS TO 60 MILES EAST OF KIRKSVILLE MISSOURI. FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU3). PRECAUTIONARY/PREPAREDNESS ACTIONS... 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. && DISCUSSION...TSTMS ARE EXPECTED TO INCREASE IN COVERAGE AND INTENSITY THIS AFTERNOON ALONG SYNOPTIC FRONT EXTENDING FROM LOW PRESSURE OVER CNTRL KS NEWD ACROSS SRN IA. OTHER STORMS ONGOING ALONG AN OUTFLOW BOUNDARY LIFTING NWD THROUGH THE I-70 CORRIDOR OF MO SHOULD STRENGTHEN AS WELL. GIVEN THE COMBINATION OF STRONG INSTABILITY AND 40-50 KT OF DEEP-LAYER SHEAR THE POTENTIAL WILL EXIST FOR INTENSE SUPERCELLS CAPABLE OF VERY LARGE HAIL AND DAMAGING WINDS. GIVEN THE MODEST LOW-LEVEL SHEAR...TORNADO POTENTIAL WILL BE MODULATED BY MATURE STORMS INTERACTING WITH THE SYNOPTIC FRONT AND OUTFLOW BOUNDARY WHERE VORTICITY IS ENHANCED. AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT TO 3 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 550. MEAN STORM MOTION VECTOR 26025. ...MEAD