MESOSCALE DISCUSSION 0255 NWS STORM PREDICTION CENTER NORMAN OK 1117 AM CST SUN MAR 12 2006

   AREAS AFFECTED...NORTHERN MO/CENTRAL IL

   CONCERNING...SEVERE THUNDERSTORM WATCH 72...

   VALID 121717Z - 121845Z

SEVERE THUNDERSTORM WATCH 72 CONTINUES UNTIL 21Z FOR NORTHERN MO INTO WEST CENTRAL IL. AN ADDITIONAL WATCH EASTWARD INTO CENTRAL IL MAY BE NEEDED SOON.

ONGOING SEVERE THREAT PERSISTS ACROSS WW 72...WITH EASTERN EXTENT HIGHLIGHTED BY SUPERCELL WITH TORNADIC HISTORY ONGOING ACROSS MONROE/SHELBY COUNTIES OF NORTHEAST MO AS OF 1715Z. THIS ACTIVITY APPEARS TO BE FOCUSED ALONG SECONDARY/NORTHERN WEAK BAROCLINIC ZONE DRAPED ACROSS NORTHEAST MO INTO CENTRAL IL. ALTHOUGH THERMODYNAMIC PROFILES WOULD INITIALLY APPEAR HOSTILE TO SURFACE BASED CONVECTION...ORGANIZATION OF ONGOING STORM/S AND MODEST DOWNSTREAM HEATING/INFLUX OF PROGRESSIVELY MORE UNSTABLE AIRMASS MAY REQUIRE AN ADDITIONAL WATCH ISSUANCE SOON INTO CENTRAL IL.

   ..GUYER.. 03/12/2006

       ATTN...WFO...LOT...ILX...LSX...DVN...EAX...

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