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 54311
The USDA's 2023 Plant Hardiness Zone Map puts ZIP 54311 in zone 5b (the coldest night of a typical year: -15 to -10°F).
The nearest station, Denmark, WI, is 10 miles from the ZIP's center: its last spring frost comes after May 6 in half of years and after May 20 in one year in ten.
| Station | Distance | Elevation | Last frost (median) | 1 in 10 after | First frost (median) | Hardiness zone |
|---|---|---|---|---|---|---|
| Denmark, WIDenmark Wastewater Treatment Plant | 10 mi | 811 ft | May 6 | May 20 | October 12 | – |
| Green Bay Botanical, WI | 11 mi | 694 ft | May 7 | May 22 | October 9 | – |
| Green Bay, WIGreen Bay A S International Airport | 11 mi | 682 ft | April 30 | May 16 | October 9 | 5a |
| Ashwaubenon, WIGreen Bay Weather Office | 11 mi | 682 ft | May 1 | May 16 | October 11 | – |
| Kewaunee, WI | 19 mi | 593 ft | May 1 | May 17 | October 18 | 6a |
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 Denmark
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 1 | May 24 | May 18 | May 4 | October 1 | September 19 |
| 32°F | May 20 | May 11 | May 6 | April 22 | October 12 | September 30 |
| 28°F (hard freeze) | May 9 | April 30 | April 23 | April 9 | October 26 | October 11 |
| 24°F | April 24 | April 17 | April 11 | March 29 | November 5 | October 26 |
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.