Tornado Watch Issued for Parts of Northern Illinois until 9pm Monday

A Tornado Watch has been issued for Carroll, Whiteside, Ogle, Lee and DeKalb counties until 9pm.
Thunderstorms have quickly developed over northwest Illinois Monday afternoon following rainfall earlier in the day.  There was a severe thunderstorm warning for southeast DeKalb County earlier but that storm has moved further towards Chicago.

Tornado Warnings have been ongoing over southeast Iowa near a warm front that is draped from northeast Iowa, through the Quad Cities and into central Illinois.  Thunderstorms have developed north of the warm front in northwest Illinois and are currently moving to the northeast.  These storms do not have any warnings attached to them, but will likely bring heavy rainfall as they move through. 
Timeline for storms to move through northern Illinois looks to be between now and 6pm/7pm.  Isolated showers/storms expected Monday night into Tuesday morning.