Monticello, IL 61884 Frost Dates
Frost dates for Monticello, IL, ZIP 61884
The last spring frost here typically falls around 04/23, about 238 days from today. The first fall frost typically arrives around 10/13, about 170 frost-free days later.
Monticello 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 Monticello 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.
The actual range around Monticello's last frost
04/23 is the middle of 30 years of NOAA records, not a promise. Plant by 04/09 and you're betting against frost in roughly 9 years out of 10. 05/09 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Monticello compares
At roughly 170 frost-free days, Monticello places 28,967 of 40,283 ZIP codes in this dataset. Within IL, it ranks 1,391 of 1,548.
Learn more
local microclimates explains what one yard in Monticello can differ from the 61884 normal, and zone vs. frost date explains why Zone 6a and Monticello's frost date answer different questions.