Frost Dates for 55371 — Princeton, Minnesota

Half of springs at Santiago 3 E, MN see their last 32°F night by May 7; only one in ten is past it by April 24, and one in ten still has one after May 22. Planting tender crops after May 13 leaves a 30% risk of a frost on them, after May 17 20%, and after May 22 10%. The 15 days between the even-odds date and the one-in-ten date is wider than at 64% of the 142 Minnesota stations behind this site's ZIP pages.

In fall the first 32°F night comes by September 28 in half of years, as early as September 15 one year in ten, and holds off past October 11 one year in ten. A hard freeze of 28°F follows 10 days later, around October 8; in spring the one-in-ten date for 28°F is May 12, 10 days before the 32°F one. The freeze-free season lasts 144 days in a typical year, shorter than at 67% of the 142 Minnesota stations; it reaches 161 days one year in ten and falls short of 125 one year in ten. On average 170 nights a year drop to 32°F or below. Nights of 36°F, when frost can still settle on leaves in low, open spots, continue 11 days longer, to about May 18, and return around September 20. Severe cold of 16°F or below comes every winter, usually between November 8 and March 31.

July is the warmest month at Santiago 3 E, MN, averaging 81°F by day and 59°F at night; January is the coldest at 22°F and 4°F. A freezing night is all but certain in every month from October to April (a 90% chance or more). From June to August the chance of a 32°F night stays under 10% each month. In spring, May still brings one in 70% of years.

Warmth for growing adds up to 2,365 growing degree days a year (base 50°F), fewer than at 54% of the 142 Minnesota stations. 33% of them (785) have built up by the end of June, and July adds the most, 620. Precipitation totals 30.7 inches a year, most in June (4.2") and least in January (0.8"); May to September bring 62% of it.

The nearest other station, Milaca, MN, 13 miles north of Princeton, has a last frost 1 day later (May 8), a first frost 3 days later (October 1), a season 1 day shorter.

The first measurable snow (0.1 inch or more) in Princeton usually arrives around November 22, and the last of the season around April 4. Those are the middle dates across the winters of 1991–2020 at Santiago 3 E, MN, 9 miles away: half of years saw snow earlier, half later. Every one of those winters saw snow. The last 32°F night of spring typically comes 33 days after the last snow.

ZIP 55371 is 9 miles from Santiago 3 E, MN, which stands at 1,010 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 1 other ZIP code shares the station. The 2023 USDA Plant Hardiness Zone Map lists ZIP 55371 in zone 4b, the band where the coldest night of the year averaged -25 to -20°F (-31.7 to -28.9°C) over 1991–2020; a zone describes winter lows, not frost dates.