Dense fog developing Monday night

Update:
A Dense Fog Advisory has been issued now for all of Northern Illinois and most of Southern Wisconsin.  This advisory will last through Noon Tuesday.  Visibility has quickly fallen under a mile in nearly all locations as of 10pm.

A Dense Fog Advisory has been issued for Winnebago, Boone, McHenry, Ogle, Lee and DeKalb counties Monday evening through Tuesday morning.  Visibility has quickly fallen south of Rockford as a warm front moves closer.  Dense fog will continue to overspread the Stateline from south to north through the night into Tuesday morning.

Light showers developing overnight may help visibility some, but you may want to give yourself a little extra time for the commute Tuesday morning.