Frost Dates for 48631 — Kawkawlin, Michigan

Half of springs at Auburn 2NE, MI see their last 32°F night by May 3; only one in ten is past it by April 20, and one in ten still has one after May 23. Planting tender crops after May 12 leaves a 30% risk of a frost on them, after May 17 20%, and after May 23 10%. The 20 days between the even-odds date and the one-in-ten date is wider than at 95% of the 172 Michigan stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 14 in half of years, as early as September 29 one year in ten, and holds off past October 30 one year in ten. A hard freeze of 28°F follows 15 days later, around October 29; in spring the one-in-ten date for 28°F is May 10, 13 days before the 32°F one. The freeze-free season lasts 161 days in a typical year, longer than at 56% of the 172 Michigan stations; it reaches 183 days one year in ten and falls short of 138 one year in ten. On average 158 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 13 days longer, to about May 16, and return around September 30. Severe cold of 16°F or below comes every winter, usually between November 30 and March 19.

July is the warmest month at Auburn 2NE, MI, averaging 83°F by day and 58°F at night; January is the coldest at 30°F and 14°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 60% of years.

Warmth for growing adds up to 2,476 growing degree days a year (base 50°F), more than at 51% of the 172 Michigan stations. 32% of them (785) have built up by the end of June, and July adds the most, 643.

The nearest other station, Essexville, MI, 8 miles southeast of Kawkawlin, has a last frost 6 days earlier (April 27), a first frost 6 days later (October 20), a season 12 days longer.

The first measurable snow (0.1 inch or more) in Kawkawlin usually arrives around November 25, and the last of the season around March 19. Those are the middle dates across the winters of 1991–2020 at Essexville, MI, 7.9 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 45 days after the last snow.

ZIP 48631 is 4 miles from Auburn 2NE, MI, which stands at 605 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 2 other ZIP codes share the station; its figures are presented in full for 48611 (Auburn). The 2023 USDA Plant Hardiness Zone Map lists ZIP 48631 in zone 6a, the band where the coldest night of the year averaged -10 to -5°F (-23.3 to -20.6°C) over 1991–2020; a zone describes winter lows, not frost dates.