Henry

... Areas of dense fog developing...

Fog was developing across portions of northwest Illinois early this
morning. Areas of dense fog... with visibilities of a quarter mile
or less... can be expected this morning. Dense fog will mainly
favor river valleys and other low lying locations. The fog should
dissipate by 9 or 10 am.

Motorists should drive with extra caution and allow additional
travel time. Use low beams... reduce speed... and allow for plenty
of room between you and other vehicles.