MESOSCALE DISCUSSION 0001
   NWS STORM PREDICTION CENTER NORMAN OK
   0614 PM CST SUN DEC 31 2006
   
   AREAS AFFECTED...NE IL...NRN IN...SRN LWR MI
   
   CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY 
   
   VALID 010014Z - 010215Z
   
   ONGOING CONVECTIVE CLUSTER...OCCURRING NEAR CYCLONIC VORTICITY
   CENTER ASSOCIATED WITH COLD CORE OF NORTHEASTWARD ACCELERATING UPPER
   LOW...HAS BEEN GENERATING STRONG GUSTY WINDS APPROACHING SEVERE
   LIMITS.  PEAK GUSTS NEAR/IN EXCESS OF 40 KTS HAVE BEEN RECORDED AT
   BLOOMINGTON/CHAMPAIGN AND MATTOON...LIKELY IN RESPONSE TO
   EVAPORATIVE COOLING/DOWNWARD MOMENTUM TRANSFER IN STRONGER
   DOWNDRAFTS.  THOUGH DAYTIME SURFACE HEATING HAS BEEN WEAK...
   LOWER/MID TROPOSPHERIC COOLING/DRYING AHEAD OF MAIN SURFACE FRONT
   HAS CONTRIBUTED TO VERY STEEP LOW-LEVEL LAPSE RATE ENVIRONMENT
   SUPPORTING THIS PROCESS...WHICH MAY NOT BE APPRECIABLY AFFECTED BY
   LOSS OF DAYTIME HEATING.  THUS...RISK FOR STRONG GUSTY...
   POTENTIALLY DAMAGING WINDS MAY CONTINUE WITH CONVECTION AS IT
   SPREADS ACROSS LAFAYETTE IND AREA AND AREAS NEAR/SOUTH OF
   CHICAGO...THROUGH NORTHERN INDIANA INTO SOUTHERN LOWER MICHIGAN BY
   LATE EVENING.  AS ACTIVITY APPROACHES THE DETROIT AREA TOWARD
   04-06Z...MODEL GUIDANCE SUGGESTS STORMS MAY BEGIN TO DIMINISH
   ASSOCIATED WITH STABILIZATION AS LOW-LEVEL COOLING OVERTAKES COOLING
   ALOFT.
   
   ..KERR.. 01/01/2007
   
   
   ATTN...WFO...DTX...IWX...GRR...IND...LOT...ILX...
   
   41118844 41898801 42858666 42978527 42168426 40928502
   39738605 39208713 39238780 40038772 40638817