Frost Dates for 49680 — South Boardman, Michigan

Half of springs at S Boardman 2W, MI see their last 32°F night by May 24; only one in ten is past it by May 3, and one in ten still has one after June 8. Planting tender crops after May 31 leaves a 30% risk of a frost on them, after June 3 20%, and after June 8 10%. The 15 days between the even-odds date and the one-in-ten date is narrower than at 55% of the 172 Michigan stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 4 in half of years, as early as September 17 one year in ten, and holds off past October 19 one year in ten. A hard freeze of 28°F follows 12 days later, around October 16; in spring the one-in-ten date for 28°F is May 28, 11 days before the 32°F one. The freeze-free season lasts 133 days in a typical year, shorter than at 81% of the 172 Michigan stations; it reaches 155 days one year in ten and falls short of 110 one year in ten. On average 169 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 June 4, and return around September 21. Severe cold of 16°F or below comes every winter, usually between November 25 and April 2.

July is the warmest month at S Boardman 2W, MI, averaging 81°F by day and 55°F at night; January is the coldest at 27°F and 13°F. A freezing night is all but certain in every month from October to April (a 90% chance or more). From July to August the chance of a 32°F night stays under 10% each month. In spring, May still brings one in 89% of years and June still brings one in 27% of years.

Warmth for growing adds up to 2,150 growing degree days a year (base 50°F), fewer than at 67% of the 172 Michigan stations. 31% of them (668) have built up by the end of June, and July adds the most, 570.

The nearest other station, Kalkaska, MI, 7 miles northeast of South Boardman, has the same 50% last-frost date, a first frost 3 days earlier (October 1), a season 5 days shorter.

The first measurable snow (0.1 inch or more) in South Boardman usually arrives around November 6, and the last of the season around April 14. Those are the middle dates across the winters of 1991–2020 at Kalkaska, MI, 6.7 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 40 days after the last snow.

ZIP 49680 is 3 miles from S Boardman 2W, MI, which stands at 1,046 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. The 2023 USDA Plant Hardiness Zone Map lists ZIP 49680 in zone 5b, the band where the coldest night of the year averaged -15 to -10°F (-26.1 to -23.3°C) over 1991–2020; a zone describes winter lows, not frost dates.