Chicago, IL – Temperatures are set to plunge into the 30s across northern Illinois tonight, creating an immediate frost risk that will intensify into Sunday night and early Monday morning.
According to the National Weather Service in Chicago, breezy conditions will persist through the weekend, with highs struggling in the upper 40s to mid-50s. Overnight lows will drop to 30–39 degrees Saturday night, with even colder readings of 27–37 degrees expected Sunday night into Monday morning. The coldest conditions are likely west of the Fox Valley and in outlying suburban areas, where frost could become widespread.
Chicago’s urban core may stay slightly warmer, but surrounding communities including Aurora, Joliet, Elgin, and Waukegan face a higher risk of frost formation. Isolated to scattered showers may develop Sunday afternoon, but the primary concern remains the sharp overnight temperature drop.
Residents should cover sensitive plants, bring outdoor vegetation inside, and avoid leaving pets outdoors overnight. Gardeners and farmers should take extra precautions to protect early-season crops.
Temperatures rebound into the 70s by Tuesday, but frost advisories remain possible through Monday morning as this cold stretch peaks.
