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 54902
The USDA's 2023 Plant Hardiness Zone Map puts ZIP 54902 in zone 5b (the coldest night of a typical year: -15 to -10°F).
The nearest station, Oshkosh, WI, is 3 miles from the ZIP's center: its last spring frost comes after April 30 in half of years and after May 13 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 |
|---|---|---|---|---|---|---|
| Oshkosh, WIOshkosh Wittman Airport | 3 mi | 782 ft | April 30 | May 13 | October 13 | 5b |
| Oshkosh station, WI | 5 mi | 750 ft | April 24 | May 8 | October 20 | 5b |
| Ripon, WI5 mi NE | 11 mi | 930 ft | May 1 | May 14 | October 11 | – |
| Fond Du Lac Wastewater Treatment Plant, WI | 11 mi | 750 ft | May 1 | May 17 | October 12 | 5b |
| Fond du Lac, WIFond Du Lac County Airport | 13 mi | 809 ft | May 1 | May 17 | October 10 | 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 Oshkosh
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 25 | May 17 | May 10 | April 28 | October 1 | September 20 |
| 32°F | May 13 | May 5 | April 30 | April 15 | October 13 | September 29 |
| 28°F (hard freeze) | May 2 | April 24 | April 18 | April 4 | October 26 | October 8 |
| 24°F | April 21 | April 12 | April 6 | March 24 | November 5 | October 23 |
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.