Prior Lake, MN 55372 Frost Dates
Prior Lake, MN: when does the frost end?
Around 05/02 is the usual last spring frost, about 247 days away. Fall's first freeze usually shows up around 10/05, roughly 153 days after the last spring frost.
Zone 4b (-25 to -20°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 Prior Lake, not a forecast for this year.
Stretching the season past the first frost
With roughly 5 weeks until Prior Lake's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
Why 05/02 isn't a guarantee
05/02 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/17 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/18 and only about 1 year in 10 sees frost after that.
Prior Lake against the rest of the dataset
About 153 days separate Prior Lake's last and first frost, putting it 34,482 of 40,283 ZIP codes nationally. Within MN, it ranks 400 of 943.
Learn more
Before leaning on 55372's figures: local microclimates explains what one yard in Prior Lake can differ from the 55372 normal, while zone vs. frost date explains why Zone 4b and Prior Lake's frost date answer different questions.