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 48506
The USDA's 2023 Plant Hardiness Zone Map puts ZIP 48506 in zone 6a (the coldest night of a typical year: -10 to -5°F).
The nearest station, Burton, MI, is 2 miles from the ZIP's center: its last spring frost comes after May 8 in half of years and after May 22 in one year in ten.
| Station | Distance | Elevation | Last frost (median) | 1 in 10 after | First frost (median) | Hardiness zone |
|---|---|---|---|---|---|---|
| Burton, MI4 mi N | 2 mi | 757 ft | May 8 | May 22 | October 5 | – |
| Flint (7 mi W), MI | 8 mi | 679 ft | May 3 | May 20 | October 13 | – |
| Flint, MIFlint Weather Station | 9 mi | 770 ft | May 6 | May 23 | October 10 | 5b |
| Goodrich, MI | 12 mi | 910 ft | May 1 | May 18 | October 14 | – |
| Lapeer (2 mi W), MI | 13 mi | 837 ft | May 4 | May 21 | October 13 | – |
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 Burton
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) | June 3 | May 26 | May 20 | May 6 | September 25 | September 12 |
| 32°F | May 22 | May 14 | May 8 | April 28 | October 5 | September 22 |
| 28°F (hard freeze) | May 13 | May 3 | April 29 | April 18 | October 19 | October 4 |
| 24°F | May 1 | April 24 | April 20 | April 8 | November 1 | October 19 |
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.