A dense fog advisory will remain in effect through at least 9 a.m. in areas south of the city of Chicago, with icy road conditions expected in impacted areas.
According to the National Weather Service, the advisory covers southern Cook County, as well as Grundy, Will and Kankakee counties in Illinois. Lake, Porter, LaPorte, Newton and Jasper counties in Indiana are also affected.
The advisory comes amid pockets of dense fog in the region, with reports of travel issues caused by reduced visibility and because of slick spots on the road as temperatures hover around the freezing mark.
Motorists are being urged to use caution when driving through foggy conditions.
Visibility of one-quarter mile or less is expected.
The fog is expected to dissipate between 9 a.m. and 10 a.m., but localized pockets could continue beyond that time, according to officials.
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