Frost Dates for 55038 — Hugo, Minnesota

Half of springs at Vadnais Lake, MN see their last 32°F night by April 23; only one in ten is past it by April 9, and one in ten still has one after May 7. Planting tender crops after April 29 leaves a 30% risk of a frost on them, after May 1 20%, and after May 7 10%. The 14 days between the even-odds date and the one-in-ten date is narrower than at 37% of the 142 Minnesota stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 20 in half of years, as early as October 3 one year in ten, and holds off past November 2 one year in ten. A hard freeze of 28°F follows 11 days later, around October 31; in spring the one-in-ten date for 28°F is April 27, 10 days before the 32°F one. The freeze-free season lasts 177 days in a typical year, longer than at 97% of the 142 Minnesota stations; it reaches 197 days one year in ten and falls short of 159 one year in ten. On average 157 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 9 days longer, to about May 2, and return around October 7. Severe cold of 16°F or below comes every winter, usually between November 21 and March 24.

July is the warmest month at Vadnais Lake, MN, averaging 83°F by day and 64°F at night; January is the coldest at 25°F and 8°F. A freezing night is all but certain in every month from November to April (a 90% chance or more). From June to September the chance of a 32°F night stays under 10% each month. In spring, May still brings one in 23% of years.

Warmth for growing adds up to 2,946 growing degree days a year (base 50°F), more than at 96% of the 142 Minnesota stations. 34% of them (995) have built up by the end of June, and July adds the most, 728. Precipitation totals 33.1 inches a year, most in June (4.5") and least in January (0.8"); May to September bring 63% of it.

The nearest other station, Stillwater 2SW, MN, 11 miles southeast of Hugo, has a last frost 7 days later (April 30), a first frost 9 days earlier (October 11), a season 14 days shorter.

The first measurable snow (0.1 inch or more) in Hugo usually arrives around November 27, and the last of the season around March 24. Those are the middle dates across the winters of 1991–2020 at Vadnais Lake, MN, 9.2 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 30 days after the last snow.

ZIP 55038 is 9 miles from Vadnais Lake, MN, which stands at 890 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 5 other ZIP codes share the station; its figures are presented in full for 55112 (New Brighton). The 2023 USDA Plant Hardiness Zone Map lists ZIP 55038 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.