Tuesday Evening Thunderstorms

10:25pm Update: The overall severe threat continues to decrease Tuesday evening but thunderstorms will continue to move in from the west through at least Midnight, likely until 2am for some.  The biggest threat with storms will be heavy rainfall.  A Flash Flood Warning remains in effect for central Winnebago County until 11:45pm. 



9:45pm Update: A Severe Thunderstorm Warning has been issued for far southeast DeKalb County until 10:15pm Tuesday evening.  The main part of the storm, however, is mostly out of DeKalb County and will move to the east.  Additional thunderstorms continue to move in from the west with the greatest concern being
heavy rainfall.







UPDATE: A Flash Flood Warning has been issued for central Winnebago County until 11:45pm Tuesday evening. Radar estimates of nearly two inches of rain has come down with repeated rounds of thunderstorms over Winnebago County. The storm that prompted the warning is beginning to weaken, but standing water and flooding will remain a concern after sunset.

 
7:30pm Update:  Additional thunderstorms are beginning to develop west of Rockford and Winnebago County, from eastern Stephenson/western Winnebago counties, to Carroll and Whiteside counties.








Thunderstorms were quick to develop Tuesday evening over southern Wisconsin and far northern Illinois.  While there are no active warnings in place, some of the stronger storms will be capable of wind gusts to 50 mph, small hail and heavy rainfall.  However, I think the greatest concern with the storms will be the heavy rainfall and possible localized flooding.  Storms that get connected to an outflow boundary may produce strong winds in excess of 50 mph, and perhaps could have some rotation. 

A Flood Advisory has been issued for Winnebago and Boone counties until 9:30pm for the possibility of localized flooding.  The storm threat will last through 9pm, with most storms out of the area by Midnight.