Frost dates by ZIP code: The nearest NOAA stations to your ZIP, 1991-2020 normals
Enter a five-digit ZIP code. PlainClimate finds its center (Census Bureau 2024) and the five nearest NOAA stations with frost dates, and shows each station's last spring and first autumn 32°F dates with its distance and elevation.
Frost dates near ZIP 48312
The USDA's 2023 Plant Hardiness Zone Map puts ZIP 48312 in zone 6b (the coldest night of a typical year: -5 to 0°F).
The nearest station, Mount Clemens, MI, is 10 miles from the ZIP's center: its last spring frost comes after April 30 in half of years and after May 15 in one year in ten. By the USDA's method its plant hardiness zone is 6b.
| Station | Distance | Elevation | Last frost (median) | 1 in 10 after | First frost (median) | Hardiness zone |
|---|---|---|---|---|---|---|
| Mount Clemens, MIMount Clemens Ang Base | 10 mi | 580 ft | April 30 | May 15 | October 24 | 6b |
| Detroit City Airport, MI | 10 mi | 626 ft | April 21 | May 6 | October 31 | 6b |
| Grosse Pointe Farms, MI | 12 mi | 613 ft | April 29 | May 13 | October 22 | 6b |
| Pontiac Wastewater Treatment Plant, MI | 14 mi | 890 ft | April 26 | May 12 | October 22 | 6b |
| Dearborn #2, MI | 17 mi | 605 ft | April 27 | May 11 | October 25 | – |
Frost comes later in spring at higher and colder stations and earlier in low, open ground: prefer a station at a similar elevation to yours. Hardiness zone in the table: the USDA's rule (the average of each year's coldest night, 1991-2020) applied to the station's own record.
Every frost threshold at Mount Clemens
NOAA publishes the dates for several temperatures and odds. A 30% spring date means a 3-in-10 chance of a later frost (the convention almanacs use); 50% is the median; 10% the cautious date.
| Threshold | Spring, 10% | Spring, 30% | Spring, 50% | Spring, 90% | Autumn, 50% | Autumn, 10% |
|---|---|---|---|---|---|---|
| 36°F (light frost) | May 28 | May 19 | May 11 | April 28 | October 9 | September 26 |
| 32°F | May 15 | May 5 | April 30 | April 16 | October 24 | October 7 |
| 28°F (hard freeze) | May 3 | April 24 | April 18 | April 3 | November 3 | October 20 |
| 24°F | April 20 | April 11 | April 5 | March 23 | November 13 | November 1 |
Source: NOAA NCEI 1991-2020 annual normals; ZIP centers: Census Bureau 2024 Gazetteer; USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026. Autumn 10%: one year in ten has its first frost before this date.