Willow River, MN 55795 Frost Dates
Willow River, MN: when does the frost end?
Typically, the last spring freeze lands around 05/12, roughly 257 days out. Fall's first freeze usually shows up around 10/02, roughly 144 days after the last spring frost.
Zone 4a (-30 to -25°F average annual minimum) comes from the USDA Plant Hardiness Zone Map; the frost dates above are the 1991-2020 normal at the nearest reporting NOAA station for Willow River, not a forecast for this year.
Stretching the season past the first frost
With roughly 5 weeks until Willow River's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
How much risk comes with planting early here
05/12 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/28 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/26 and only about 1 year in 10 sees frost after that.
Willow River against the rest of the dataset
About 144 days separate Willow River's last and first frost, putting it 36,451 of 40,283 ZIP codes nationally. Within MN, it ranks 669 of 943.
Learn more
Before leaning on 55795's figures: the frost range explains how to read the range around Willow River's dates instead of trusting one, while local microclimates explains what one yard in Willow River can differ from the 55795 normal.