Mountain Lake, MN 56159 Frost Dates
Frost dates for Mountain Lake, MN, ZIP 56159
Typically, the last spring freeze lands around 04/30, roughly 245 days out. The first fall frost typically arrives around 10/10, about 162 frost-free days later.
The USDA Plant Hardiness Zone Map puts Mountain Lake in Zone 5a (-20 to -15°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 5a around Mountain Lake 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
04/30 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. 05/13 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Mountain Lake compares
At roughly 162 frost-free days, Mountain Lake places 31,760 of 40,283 ZIP codes in this dataset. Within MN, it ranks 181 of 943.
Learn more
local microclimates explains what one yard in Mountain Lake can differ from the 56159 normal, and zone vs. frost date explains why Zone 5a and Mountain Lake's frost date answer different questions.