Frost Dates for 49660 — Manistee, Michigan

Half of springs at Manistee 3SE, MI see their last 32°F night by May 14; only one in ten is past it by April 27, and one in ten still has one after May 31. Planting tender crops after May 22 leaves a 30% risk of a frost on them, after May 26 20%, and after May 31 10%. The 17 days between the even-odds date and the one-in-ten date is wider than at 62% of the 172 Michigan stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 12 in half of years, as early as September 27 one year in ten, and holds off past November 1 one year in ten. A hard freeze of 28°F follows 20 days later, around November 1; in spring the one-in-ten date for 28°F is May 21, 10 days before the 32°F one. The freeze-free season lasts 151 days in a typical year, shorter than at 63% of the 172 Michigan stations; it reaches 177 days one year in ten and falls short of 127 one year in ten. On average 140 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 27, and return around September 30. Severe cold of 16°F or below comes every winter, usually between December 8 and March 25.

July is the warmest month at Manistee 3SE, MI, averaging 80°F by day and 59°F at night; January is the coldest at 30°F and 19°F. A freezing night is all but certain in every month from November 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 79% of years.

Warmth for growing adds up to 2,434 growing degree days a year (base 50°F), fewer than at 52% of the 172 Michigan stations. 31% of them (753) have built up by the end of June, and July adds the most, 602. Precipitation totals 36.4 inches a year, most in October (4.1") and least in February (1.6"); May to September bring 47% of it.

The nearest other station, Wellston 1N, MI, 16 miles east of Manistee, has a last frost 14 days later (May 28), a first frost 17 days earlier (September 25), a season 32 days shorter.

The first measurable snow (0.1 inch or more) in Manistee 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, 15.6 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 29 days after the last snow.

ZIP 49660 is 2 miles from Manistee 3SE, MI, which stands at 670 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. The 2023 USDA Plant Hardiness Zone Map lists ZIP 49660 in zone 6b, the band where the coldest night of the year averaged -5 to 0°F (-20.6 to -17.8°C) over 1991–2020; a zone describes winter lows, not frost dates.