Weather
Illinois Frost Alert: Protect Plants Friday as Lows Near 31°
Chicago, IL – Residents across northern Illinois should prepare to protect sensitive outdoor plants Friday evening, Oct. 16, as a strong cold front brings much colder temperatures and the possibility
By Miles Carter · 2026-10-13T21:06:52.986Z
Chicago, IL – Residents across northern Illinois should prepare to protect sensitive outdoor plants Friday evening, Oct. 16, as a strong cold front brings much colder temperatures and the possibility of frost or freezing conditions overnight into Saturday.
According to the National Weather Service in Chicago, overnight lows Friday into Saturday, Oct. 17, are forecast to range from 31 to 43 degrees across the region. The coldest temperatures are expected away from Chicago and Lake Michigan, where some communities could fall below freezing.
Frost Could Damage Gardens and Outdoor Plants
Temperatures near or below 32 degrees can damage or kill sensitive vegetation, including tomatoes, peppers, flowers and other warm season plants.
Residents in inland portions of northern Illinois should begin preparing now, particularly those with gardens, potted plants and landscaping vulnerable to cold weather.
Even where temperatures remain slightly above freezing, frost can develop under favorable conditions.
How to Protect Plants Before Friday Night
Homeowners and gardeners can take several precautions before temperatures drop:
Bring potted plants and delicate flowers indoors Friday afternoon. Cover vulnerable garden plants with frost cloths, sheets or lightweight blankets. Secure coverings so they extend to the ground and retain warmth. Avoid placing plastic directly against plant leaves. Remove coverings Saturday morning once temperatures rise above freezing. Rain and Wind Arrive Before the Cold
Before the temperature drop, scattered showers and thunderstorms are expected Tuesday night, with the greatest coverage near and south of Interstate 88.
Additional widespread rain and possible thunderstorms return Thursday, Oct. 15, before a strong cold front brings drier, windier conditions Friday.
Friday afternoon highs are expected to reach only 54 to 58 degrees, a noticeable change from Wednesday's forecast highs of 64 to 73 degrees.
Forecasters also expect northwest winds and possible lake effect showers in northwest Indiana.
Residents should monitor updated forecasts for frost or freeze advisories as Friday approaches.