Washburn, IL 61545 Frost Dates
Frost dates for Washburn, IL, ZIP 61545
The last spring frost here typically falls around 04/20, about 235 days from today. The first fall frost typically arrives around 10/17, about 178 frost-free days later.
Washburn 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 Washburn 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.
How much risk comes with planting early here
04/20 is the middle of 30 years of NOAA records, not a promise. Plant by 04/05 and you're betting against frost in roughly 9 years out of 10. 05/07 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Washburn compares
Washburn's growing season runs about 178 days, ranking 25,820 of 40,283 US ZIP codes measured here, longest to shortest. Within IL, it ranks 1,090 of 1,548.
Learn more
zone vs. frost date explains why Zone 5b and Washburn's frost date answer different questions, and the frost range explains how to read the range around Washburn's dates instead of trusting one.