Frost Dates for 48371 — Oxford, Michigan

Half of springs at Pontiac Wwtp, MI see their last 32°F night by April 26; only one in ten is past it by April 15, and one in ten still has one after May 12. Planting tender crops after May 2 leaves a 30% risk of a frost on them, after May 5 20%, and after May 12 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 October 22 in half of years, as early as October 7 one year in ten, and holds off past November 4 one year in ten. A hard freeze of 28°F follows 13 days later, around November 4; in spring the one-in-ten date for 28°F is April 30, 12 days before the 32°F one. The freeze-free season lasts 177 days in a typical year, longer than at 92% of the 172 Michigan stations; it reaches 195 days one year in ten and falls short of 158 one year in ten. On average 135 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 9 days longer, to about May 5, and return around October 10. Severe cold of 16°F or below comes every winter, usually between December 8 and March 17.

July is the warmest month at Pontiac Wwtp, MI, averaging 82°F by day and 63°F at night; January is the coldest at 31°F and 17°F. A freezing night is all but certain in every month from November to April (a 90% chance or more). From June to September the chance of a 32°F night stays under 10% each month. In spring, May still brings one in 34% of years.

Warmth for growing adds up to 2,869 growing degree days a year (base 50°F), more than at 87% of the 172 Michigan stations. 33% of them (943) have built up by the end of June, and July adds the most, 700. Precipitation totals 33.9 inches a year, most in May (3.8") and least in February (1.9"); May to September bring 48% of it.

The nearest other station, Pontiac Oakland Co International Airport, MI, 13 miles southwest of Oxford, has a last frost 3 days later (April 29), a first frost 2 days earlier (October 20), a season 5 days shorter.

The first measurable snow (0.1 inch or more) in Oxford usually arrives around November 25, and the last of the season around March 24. Those are the middle dates across the winters of 1991–2020 at Pontiac Wwtp, MI, 12.8 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 33 days after the last snow.

ZIP 48371 is 13 miles from Pontiac Wwtp, MI, which stands at 890 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 28 other ZIP codes share the station; its figures are presented in full for 48307 (Rochester Hills). The 2023 USDA Plant Hardiness Zone Map lists ZIP 48371 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.