SPC MESOSCALE DISCUSSION 0493 FOR ERN IA..SRN WI..NRN/CENTRAL IL
CONCERNING...SEVERE THUNDERSTORM POTENTIAL...TORNADO WATCH 134...

VALID 112005Z - 112200Z

WW 134 IS EXPECTED TO BE REPLACED WITH NEW TORNADO WATCH EXTENDING
FARTHER EAST INTO SRN WI AND PARTS OF NRN/CENTRAL IL WITHIN THE
HOUR.

SURFACE WARM FRONT APPEARS TO HAVE LIFTED NWD INTO SRN WI AND
CENTRAL IA AT THIS TIME...WITH WARM SECTOR TEMPERATURES EXPECTED TO
REMAIN IN THE LOWER 70S.  THIS WILL SUPPORT MODERATE INSTABILITY
ACROSS THIS REGION AS SURFACE DEW POINTS HOLD IN THE MID 60S.

SEVERAL SMALL SUPERCELLS WITH AN ENHANCED THREAT OF WIND DAMAGE
AND/OR TORNADOES ARE PERSISTING ACROSS CENTRAL IA ATTM.  THESE
STRONG TO SEVERE THUNDERSTORMS ARE REMAINING CONFINED TO THE
SURFACE BOUNDARY ARCING SSEWD ACROSS CENTRAL IA AND FAR NRN MO.  AS
LEFT EXIT REGION OF VERY STRONG MID LEVEL SPEED MAX SHIFTS EWD
ACROSS THE MID/UPPER MS VALLEY REGION INTO THE EARLY EVENING...
STRONG UVV/S WILL CONTINUE TO OVERRIDE THIS SURFACE FRONT AND
MAINTAIN A THREAT OF TORNADOES ACROSS ERN IA AND INTO PARTS OF
IL/SRN WI DURING THE NEXT SEVERAL HOURS.  

..EVANS.. 04/11/01