Frost Dates for 49656 — Luther, Michigan

Half of springs at Wellston 1N, MI see their last 32°F night by May 28; only one in ten is past it by May 13, and one in ten still has one after June 13. Planting tender crops after June 3 leaves a 30% risk of a frost on them, after June 7 20%, and after June 13 10%. The 16 days between the even-odds date and the one-in-ten date is narrower than at 38% of the 172 Michigan stations behind this site's ZIP pages.

In fall the first 32°F night comes by September 25 in half of years, as early as September 8 one year in ten, and holds off past October 10 one year in ten. A hard freeze of 28°F follows 13 days later, around October 8; in spring the one-in-ten date for 28°F is June 1, 12 days before the 32°F one. The freeze-free season lasts 119 days in a typical year, shorter than at 94% of the 172 Michigan stations; it reaches 139 days one year in ten and falls short of 96 one year in ten. On average 171 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 12 days longer, to about June 9, and return around September 14. Severe cold of 16°F or below comes every winter, usually between November 15 and April 9.

July is the warmest month at Wellston 1N, MI, averaging 81°F by day and 54°F at night; January is the coldest at 28°F and 12°F. A freezing night is all but certain in every month from October to May (a 90% chance or more). From July to August the chance of a 32°F night stays under 10% each month. In spring, June still brings one in 40% of years.

Warmth for growing adds up to 2,054 growing degree days a year (base 50°F), fewer than at 74% of the 172 Michigan stations. 32% of them (656) have built up by the end of June, and July adds the most, 538. Precipitation totals 38.2 inches a year, most in October (4.2") and least in February (2.0"); May to September bring 44% of it.

The nearest other station, Cadillac 9&10 News, MI, 18 miles northeast of Luther and 590 feet higher, has a last frost 13 days earlier (May 15), a first frost 6 days later (October 1), a season 20 days longer.

The first measurable snow (0.1 inch or more) in Luther usually arrives around November 8, and the last of the season around April 15. Those are the middle dates across the winters of 1991–2020 at Wellston 1N, MI, 17.6 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 43 days after the last snow.

ZIP 49656 is 18 miles from Wellston 1N, MI, which stands at 773 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 49304 (Baldwin). The 2023 USDA Plant Hardiness Zone Map lists ZIP 49656 in zone 5a, the band where the coldest night of the year averaged -20 to -15°F (-28.9 to -26.1°C) over 1991–2020; a zone describes winter lows, not frost dates.