May 22- Tornado Watch #323

URGENT - IMMEDIATE BROADCAST REQUESTED
   TORNADO WATCH NUMBER 323
   NWS STORM PREDICTION CENTER NORMAN OK
   1255 PM CDT SUN MAY 22 2011
   
   THE NWS STORM PREDICTION CENTER HAS ISSUED A
   TORNADO WATCH FOR PORTIONS OF 
   
          EASTERN IOWA
          WESTERN ILLINOIS
          EAST-CENTRAL KANSAS
          NORTHERN MISSOURI
   
   EFFECTIVE THIS SUNDAY AFTERNOON AND EVENING FROM 1255 PM UNTIL
   900 PM CDT.
   
   TORNADOES...HAIL TO 3 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 90 STATUTE
   MILES EAST AND WEST OF A LINE FROM 40 MILES NORTH NORTHWEST OF
   DUBUQUE IOWA TO 25 MILES WEST SOUTHWEST OF COLUMBIA MISSOURI. 
   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 321...WW 322...
   
   DISCUSSION...TSTMS ARE IN THE PROCESS OF DEVELOPING ALONG PRIMARY
   COLD FRONT EXTENDING FROM N-CNTRL IA TO E-CNTRL KS AS WELL AS ALONG
   GRAVITY WAVE-INDUCED SURFACE CONVERGENCE BOUNDARY FROM CNTRL IL INTO
   E-CNTRL MO.  AMBIENT WARM SECTOR AIR MASS IS QUITE MOIST AND
   MODERATELY TO STRONGLY UNSTABLE WITH MLCAPE VALUES OF 2000-3500
   J/KG.  WHEN COUPLED WITH 40-50 KT OF DEEP-LAYER SHEAR AND MODERATELY
   STRONG LOW-LEVEL SHEAR...THE POTENTIAL WILL EXIST FOR SUPERCELLS
   CAPABLE OF DESTRUCTIVE HAIL AND TORNADOES...SOME POSSIBLY STRONG.
   
   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
   600. MEAN STORM MOTION VECTOR 24030.