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 55446
The USDA's 2023 Plant Hardiness Zone Map puts ZIP 55446 in zone 5a (the coldest night of a typical year: -20 to -15°F).
The nearest station, New Hope, MN, is 6 miles from the ZIP's center: its last spring frost comes after April 29 in half of years and after May 12 in one year in ten. By the USDA's method its plant hardiness zone is 5a.
| Station | Distance | Elevation | Last frost (median) | 1 in 10 after | First frost (median) | Hardiness zone |
|---|---|---|---|---|---|---|
| New Hope, MN | 6 mi | 910 ft | April 29 | May 12 | October 12 | 5a |
| Minneapolis Crystal Airport, MN | 7 mi | 861 ft | April 30 | May 17 | October 8 | 5a |
| Lower St Anthony Falls, MN | 13 mi | 754 ft | April 23 | May 7 | October 16 | 5a |
| Chanhassen, MNChanhassen Weather Office | 14 mi | 946 ft | April 30 | May 15 | October 9 | 4b |
| Delano, MN | 14 mi | 975 ft | April 30 | May 14 | October 8 | – |
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 New Hope
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 23 | May 14 | May 8 | April 26 | October 1 | September 19 |
| 32°F | May 12 | May 4 | April 29 | April 15 | October 12 | September 29 |
| 28°F (hard freeze) | May 1 | April 24 | April 19 | April 5 | October 22 | October 8 |
| 24°F | April 22 | April 14 | April 9 | March 28 | 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.