Anchor, IL 61731 Frost Dates
Frost dates for Anchor, IL, ZIP 61731
The last spring frost here typically falls around 04/21, about 236 days from today. The first fall frost typically arrives around 10/17, about 178 frost-free days later.
Anchor sits in USDA Zone 6a (-10 to -5°F average annual minimum). The dates above are NOAA's 1991-2020 normal at the nearest reporting station, a 30-year average, not a forecast.
What to do before the first frost
Zone 6a around Anchor has about 7 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.
Why 04/21 isn't a guarantee
04/21 is the middle of 30 years of NOAA records, not a promise. Plant by 04/10 and you're betting against frost in roughly 9 years out of 10. 05/05 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Anchor compares
At roughly 178 frost-free days, Anchor places 25,932 of 40,283 ZIP codes in this dataset. Within IL, it ranks 1,111 of 1,548.
Learn more
zone vs. frost date explains why Zone 6a and Anchor's frost date answer different questions, and the frost range explains how to read the range around Anchor's dates instead of trusting one.