Frost Dates for 49676 — Rapid City, Michigan

Half of springs at Kalkaska, MI see their last 32°F night by May 24; only one in ten is past it by May 7, and one in ten still has one after June 7. Planting tender crops after May 30 leaves a 30% risk of a frost on them, after June 2 20%, and after June 7 10%. The 14 days between the even-odds date and the one-in-ten date is narrower than at 80% of the 172 Michigan stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 1 in half of years, as early as September 14 one year in ten, and holds off past October 14 one year in ten. A hard freeze of 28°F follows 11 days later, around October 12; in spring the one-in-ten date for 28°F is May 26, 12 days before the 32°F one. The freeze-free season lasts 128 days in a typical year, shorter than at 88% of the 172 Michigan stations; it reaches 151 days one year in ten and falls short of 104 one year in ten. On average 179 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 5, and return around September 17. Severe cold of 16°F or below comes every winter, usually between November 22 and April 4.

July is the warmest month at Kalkaska, MI, averaging 79°F by day and 55°F at night; January is the coldest at 26°F and 11°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 25% of years.

Warmth for growing adds up to 1,946 growing degree days a year (base 50°F), fewer than at 83% of the 172 Michigan stations. 32% of them (614) have built up by the end of June, and July adds the most, 524. Precipitation totals 33.8 inches a year, most in October (4.2") and least in February (1.5"); May to September bring 49% of it.

The nearest other station, Old Mission 3SSW, MI, 13 miles northwest of Rapid City and 379 feet lower, has a last frost 11 days earlier (May 13), a first frost 18 days later (October 19), a season 30 days longer.

The first measurable snow (0.1 inch or more) in Rapid City 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, 8.7 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 49676 is 9 miles from Kalkaska, MI, which stands at 1,035 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 49646 (Kalkaska). The 2023 USDA Plant Hardiness Zone Map lists ZIP 49676 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.