Frost Dates for 48435 — Fostoria, Michigan

Half of springs at Lapeer 2W, MI see their last 32°F night by May 4; only one in ten is past it by April 21, and one in ten still has one after May 21. Planting tender crops after May 11 leaves a 30% risk of a frost on them, after May 15 20%, and after May 21 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 13 in half of years, as early as September 30 one year in ten, and holds off past October 29 one year in ten. A hard freeze of 28°F follows 14 days later, around October 27; in spring the one-in-ten date for 28°F is May 11, 10 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 181 days one year in ten and falls short of 138 one year in ten. On average 138 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 10 days longer, to about May 14, and return around October 2. Severe cold of 16°F or below comes every winter, usually between December 2 and March 21.

July is the warmest month at Lapeer 2W, MI, averaging 82°F by day and 61°F at night; January is the coldest at 31°F and 16°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 62% of years.

Warmth for growing adds up to 2,681 growing degree days a year (base 50°F), more than at 71% of the 172 Michigan stations. 33% of them (881) have built up by the end of June, and July adds the most, 666. Precipitation totals 36.3 inches a year, most in August (4.6") and least in February (2.3"); May to September bring 48% of it.

The nearest other station, Lapeer Wwtp, MI, 13 miles south of Fostoria, has the same 50% last-frost date, a first frost 1 day later (October 14), a season 1 day shorter.

The first measurable snow (0.1 inch or more) in Fostoria usually arrives around November 17, and the last of the season around April 7. Those are the middle dates across the winters of 1991–2020 at Millington 3 SE, 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 27 days after the last snow.

ZIP 48435 is 13 miles from Lapeer 2W, MI, which stands at 837 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 1 other ZIP code shares the station; its figures are presented in full for 48421 (Columbiaville). The 2023 USDA Plant Hardiness Zone Map lists ZIP 48435 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.