Chicago, IL 60609 Frost Dates
Frost dates for Chicago, IL, ZIP 60609
Typically, the last spring freeze lands around 04/10, roughly 225 days out. 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 6a (-10 to -5°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 6a 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.
The actual range around Chicago's last frost
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
At roughly 208 frost-free days, Chicago places 15,462 of 40,283 ZIP codes in this dataset. Within IL, it ranks 58 of 1,548.
Learn more
the frost range explains how to read the range around Chicago's dates instead of trusting one, and local microclimates explains what one yard in Chicago can differ from the 60609 normal.