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 52002
The USDA's 2023 Plant Hardiness Zone Map puts ZIP 52002 in zone 5a (the coldest night of a typical year: -20 to -15°F).
The nearest station, Dubuque Lock and Dam 11, IA, is 6 miles from the ZIP's center: its last spring frost comes after April 19 in half of years and after May 4 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 |
|---|---|---|---|---|---|---|
| Dubuque Lock and Dam 11, IA | 6 mi | 620 ft | April 19 | May 4 | October 21 | 5a |
| Dubuque, IADubuque Regional Airport | 9 mi | 1,056 ft | April 28 | May 12 | October 11 | 5a |
| Cascade, IA | 20 mi | 814 ft | April 28 | May 12 | October 10 | 5a |
| Lancaster, WI4 mi WSW | 21 mi | 1,040 ft | April 27 | May 11 | October 11 | 5a |
| Galena, IL | 21 mi | 822 ft | April 26 | May 11 | October 15 | – |
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 Dubuque Lock and Dam 11
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 14 | May 6 | May 1 | April 16 | October 12 | September 29 |
| 32°F | May 4 | April 25 | April 19 | April 4 | October 21 | October 7 |
| 28°F (hard freeze) | April 22 | April 13 | April 7 | March 25 | November 1 | October 19 |
| 24°F | April 12 | April 4 | March 31 | March 14 | November 10 | October 29 |
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.