National Weather Service United States Department of Commerce

Unseasonably mild conditions will linger across central and southeast Illinois to start the new week, although colder temperatures return starting Monday night. Mostly cloudy skies will be the rule over the next couple of days, with precipitation chances increasing significantly by later tonight. Showers and a few thunderstorms are expected later tonight into Monday. Any lingering rainfall will eventually mix with and/or change to snow Monday night as the colder air returns. Little or no snow accumulation is anticipated.
Dense fog will continue to develop across portions of central Illinois this morning, frequently reducing the visibility to one-quarter mile or less. Fog is expected to linger for much of the day, but visibilities should improve somewhat by midday. Motorists should use low-beam headlights, slow down, and allow extra travel time this morning.