Cass Lake, MN 56663 Frost Dates
Cass Lake, MN: when does the frost end?
Around 05/17 is the usual last spring frost, about 262 days away. Fall's first freeze usually shows up around 09/26, roughly 131 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Cass Lake in Zone 3b (-35 to -30°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
Stretching the season past the first frost
With roughly 4 weeks until Cass Lake'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
05/17 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 05/03 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/30 and only about 1 year in 10 sees frost after that.
Cass Lake against the rest of the dataset
At roughly 131 frost-free days, Cass Lake places 38,317 of 40,283 ZIP codes in this dataset. Within MN, it ranks 836 of 943.
Learn more
Before leaning on 56663's figures: local microclimates explains what one yard in Cass Lake can differ from the 56663 normal, while zone vs. frost date explains why Zone 3b and Cass Lake's frost date answer different questions.