Chicago, Illinois – Drivers across northern Illinois and parts of northwest Indiana could encounter dangerously low visibility during the morning commute as dense fog spreads across the region, reducing visibility to as little as one-quarter mile along major highways including I-90, I-94, I-55, and I-88.
According to the National Weather Service in Chicago, Dense Fog Advisories remain in effect across much of the Chicago metro area and surrounding counties early Thursday. Visibility in many areas has dropped to 0.25 miles or less, creating hazardous travel conditions across several major transportation corridors.
The advisory covers a wide portion of northern Illinois including Cook, DuPage, Lake, Kane, McHenry, Kendall, Grundy, and Kankakee counties. Cities such as Chicago, Joliet, Aurora, Elgin, Naperville, and Waukegan may experience sudden drops in visibility through the morning hours. Areas farther west including Rockford, Belvidere, Rochelle, and Dixon are also under fog advisories.
Drivers traveling along I-90 and I-94 through Chicago, I-55 south of the city, and I-88 across the western suburbs may encounter rapidly changing visibility conditions. Fog banks can form unevenly, meaning motorists may experience clear stretches followed by sudden dense fog within a short distance.
Lake Michigan shoreline communities could see fog persist longer than inland locations due to lingering moisture and light winds. In portions of Cook, DuPage, and Lake counties, the advisory may continue into the early afternoon before conditions gradually improve.
Officials urge motorists to reduce speed, increase following distance, and use low-beam headlights when driving through fog. High beams can reflect off moisture in the air and further reduce visibility.
Conditions should slowly improve later today as daytime mixing increases, though drivers should remain alert for lingering fog patches through the afternoon.
