If driving, slow down, use your headlights, and leave plenty of distance ahead of you.

DENSE FOG ADVISORY IN EFFECT FROM 5 PM THIS AFTERNOON TO 10 AM CST SATURDAY... * WHAT...Visibility one quarter mile or less in dense fog. * WHERE...Portions of northeast Illinois and northwest Indiana. * WHEN...From 5 PM this afternoon to 10 AM CST Saturday. * IMPACTS...Hazardous driving conditions due to low visibility. * ADDITIONAL DETAILS...Visibilities have temporarily improved across the area early this afternoon. However, dense fog is expected to redevelop across the area this evening. The dense fog will persist through much of Saturday morning before improving.