FrostDateCheck

Chicago, IL 60601 Frost Dates

Frost dates for Chicago, IL, ZIP 60601

Zone 6b

Around 04/10 is the usual last spring frost, about 225 days away. The first fall frost typically arrives around 11/05, about 208 frost-free days later.

The USDA Plant Hardiness Zone Map puts Chicago in Zone 6b (-5 to 0°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.

What to do before the first frost

Zone 6b around Chicago has about 10 weeks left before the first fall frost — that's the usual window to get a cold frame up if you want to keep harvesting past it.

How much risk comes with planting early here

04/10 is the middle of 30 years of NOAA records, not a promise. Plant by 03/29 and you're betting against frost in roughly 9 years out of 10. 04/25 is the safer bet, historically only a 1-in-10 chance of frost that late.

How Chicago compares

Chicago's growing season runs about 208 days, ranking 15,457 of 40,283 US ZIP codes measured here, longest to shortest. Within IL, it ranks 53 of 1,548.

Learn more

local microclimates explains what one yard in Chicago can differ from the 60601 normal, and zone vs. frost date explains why Zone 6b and Chicago's frost date answer different questions.