ILLINOIS — The hum of traffic mixes with the rustle of drying leaves across Chicagoland this early Wednesday morning, but the air feels sharper, cooler — the kind that makes you exhale white in the streetlight. Fall’s next punch of cold is moving in fast, setting up a frost and freeze risk that could bite across the suburbs before the weekend arrives.
According to the National Weather Service in Romeoville, temperatures will slide toward the low 40s tonight under clearing skies, with readings dipping into the 30s by early Thursday in rural and far western counties. Light winds and dry air will help the chill deepen, and that combination could produce the first widespread frost of the season for parts of northern Illinois and northwest Indiana.
Gardeners should cover or bring in any sensitive plants, and drivers should expect crisp, clear mornings that could mean light frost on windshields through Friday. Air conditioners can get a break this week, but furnaces may kick on for the first time since spring.
Thursday and Friday bring calmer, sunnier days with highs near the low to mid-50s — classic late-October chill. The weekend trends milder, with highs bouncing into the upper 50s to near 60 by Sunday. However, another cool push early next week may bring temperatures back down toward freezing, hinting at an early taste of winter air settling across the Great Lakes.
Five-Day Outlook for Chicago, IL:
Wed: 50/43 – Breezy; light showers north.
Thu: 53/42 – Mostly sunny; chilly start.
Fri: 54/43 – Sunny; light breeze.
Sat: 58/49 – Mostly sunny; pleasant.
Sun: 60/51 – Partly cloudy; milder.
