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 54911
The USDA's 2023 Plant Hardiness Zone Map puts ZIP 54911 in zone 5b (the coldest night of a typical year: -15 to -10°F).
The nearest station, Appleton, WI, is 3 miles from the ZIP's center: its last spring frost comes after May 4 in half of years and after May 20 in one year in ten. By the USDA's method its plant hardiness zone is 5b.
| Station | Distance | Elevation | Last frost (median) | 1 in 10 after | First frost (median) | Hardiness zone |
|---|---|---|---|---|---|---|
| Appleton, WI | 3 mi | 792 ft | May 4 | May 20 | October 6 | 5b |
| Brillion, WI | 17 mi | 810 ft | May 6 | May 21 | October 6 | 5b |
| New London, WI | 18 mi | 800 ft | May 4 | May 19 | October 6 | 5a |
| Ashwaubenon, WIGreen Bay Weather Office | 20 mi | 682 ft | May 1 | May 16 | October 11 | – |
| Oshkosh station, WI | 20 mi | 750 ft | April 24 | May 8 | October 20 | 5b |
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 Appleton
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 29 | May 22 | May 15 | April 30 | September 28 | September 15 |
| 32°F | May 20 | May 10 | May 4 | April 21 | October 6 | September 23 |
| 28°F (hard freeze) | May 8 | April 30 | April 23 | April 9 | October 18 | October 1 |
| 24°F | April 26 | April 18 | April 12 | March 31 | November 1 | October 14 |
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.