Moderate Expected Likely Dense Fog Advisory Dense Fog Advisory issued December 25 at 11:18PM CST until December 26 at 4:00AM CST by NWS Lincoln IL Dec 25, 11:18 PM → Dec 26, 4:00 AM WHAT: Visibility one quarter mile or less in dense fog. WHERE: Portions of central, east central, southeast, and westcentral Illinois. WHEN: Until 4 AM CST Friday. IMPACTS: Low visibility could make driving conditions hazardous. + Read More If driving, slow down, use your headlights, and leave plenty of distance ahead of you. Updated: Dec 26, 12:05 AM Source: NWS Alert