Marengo, IL 60152 Frost Dates
Frost dates for Marengo, IL, ZIP 60152
The last spring frost here typically falls around 04/28, about 243 days from today. The first fall frost typically arrives around 10/12, about 166 frost-free days later.
Marengo sits in USDA Zone 5b (-15 to -10°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 5b around Marengo has about 6 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
04/28 is the middle of 30 years of NOAA records, not a promise. Plant by 04/15 and you're betting against frost in roughly 9 years out of 10. 05/14 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Marengo compares
Marengo's growing season runs about 166 days, ranking 30,352 of 40,283 US ZIP codes measured here, longest to shortest. Within IL, it ranks 1,476 of 1,548.
Learn more
local microclimates explains what one yard in Marengo can differ from the 60152 normal, and zone vs. frost date explains why Zone 5b and Marengo's frost date answer different questions.