Weather
Central Illinois Weather Oct. 16–20: Frost Risk, 30s Ahead
Central Illinois faces a sharp temperature drop heading into the weekend, with overnight lows falling into the 30s and the potential for frost Friday and Saturday nights before warmer weather returns
By Rachel Monroe · 2026-10-14T09:57:35.985Z
Central Illinois faces a sharp temperature drop heading into the weekend, with overnight lows falling into the 30s and the potential for frost Friday and Saturday nights before warmer weather returns early next week.
According to the National Weather Service in Lincoln, much cooler weather will arrive late this week across central, east central and southeast Illinois. The agency's hazardous weather outlook, issued Tuesday, Oct. 13, identifies the potential for scattered frost on both Friday and Saturday nights.
The change follows a period of showers and thunderstorms expected Wednesday and Thursday, with some storms Thursday potentially becoming strong to locally severe.
By Friday, however, the primary concern shifts from thunderstorms to colder temperatures and gusty northwest winds.
Temperatures Drop Into the 30s In Champaign, temperatures are expected to reach only 57 degrees Friday afternoon, compared with Thursday's projected high of 73 degrees.
That 16 degree decline will accompany northwest winds of 18 to 21 mph, with gusts reaching 31 mph.
Friday night temperatures are expected to fall to approximately 38 degrees, creating conditions that could support scattered frost in parts of central Illinois.
Saturday will remain cool, with sunshine and afternoon highs near 59 degrees before temperatures fall to around 38 again Saturday night.
The National Weather Service identifies both nights as potential frost periods across its broader forecast area, although frost development and temperatures will vary by location.
Residents with sensitive outdoor plants may want to monitor updated forecasts and consider protection before the colder nights arrive.
Warmer Weather Returns Sunday The chilly weekend pattern will begin easing Sunday as sunshine helps temperatures rebound.
Champaign is expected to reach approximately 69 degrees Sunday afternoon, followed by highs near 71 Monday.
By Tuesday, temperatures could climb to 75 degrees, marking an 18 degree increase from Friday's projected high.
The broader NOAA Weather Prediction Center outlook supports this transition, identifying strong Canadian high pressure as the driver of a substantial cooldown across the central United States late this week.
While some areas of the central United States could approach freezing, the supplied Champaign forecast keeps overnight lows above 32 degrees.
For central Illinois, the most significant development is the combination of a rapid cooldown, two nights with potential frost and a return to temperatures in the 70s by early next week.
Five Day Weather Outlook: Oct. 16–20 Temperatures below represent National Weather Service forecasts for Champaign, illustrating expected conditions in east central Illinois. Frost potential extends across portions of the broader Lincoln forecast area.
Friday, Oct. 16: Partly sunny and breezy, with northwest winds gusting as high as 31 mph. High near 57°. Overnight low around 38°, with scattered frost possible across portions of central Illinois. Saturday, Oct. 17: Sunny and cool, with a high near 59°. Overnight low around 38° under clear skies. Additional scattered frost possible in the region. Sunday, Oct. 18: Sunny and noticeably warmer, with a high near 69°. Overnight low around 46° under partly cloudy skies. Monday, Oct. 19: Partly sunny, with temperatures reaching approximately 71°. Overnight low around 48° with partly cloudy conditions. Tuesday, Oct. 20: Mostly sunny and warmer, with a high near 75°. Overnight low not available in the supplied forecast.