Isle, MN 56342 Frost Dates
Frost dates for Isle, MN, ZIP 56342
The last spring frost here typically falls around 05/10, about 255 days from today. The first fall frost typically arrives around 10/03, about 144 frost-free days later.
The USDA Plant Hardiness Zone Map puts Isle in Zone 4a (-30 to -25°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 4a around Isle has about 5 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 Isle's last frost
05/10 is the middle of 30 years of NOAA records, not a promise. Plant by 04/27 and you're betting against frost in roughly 9 years out of 10. 05/28 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Isle compares
About 144 days separate Isle's last and first frost, putting it 36,416 of 40,283 ZIP codes nationally. Within MN, it ranks 661 of 943.
Learn more
local microclimates explains what one yard in Isle can differ from the 56342 normal, and zone vs. frost date explains why Zone 4a and Isle's frost date answer different questions.