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 52003
The USDA's 2023 Plant Hardiness Zone Map puts ZIP 52003 in zone 5a (the coldest night of a typical year: -20 to -15°F).
The nearest station, Dubuque, IA, is 3 miles from the ZIP's center: its last spring frost comes after April 28 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 |
|---|---|---|---|---|---|---|
| Dubuque, IADubuque Regional Airport | 3 mi | 1,056 ft | April 28 | May 12 | October 11 | 5a |
| Dubuque Lock and Dam 11, IA | 8 mi | 620 ft | April 19 | May 4 | October 21 | 5a |
| Galena, IL | 15 mi | 822 ft | April 26 | May 11 | October 15 | – |
| Bellevue, IABellevue Lock and Dam 12 | 17 mi | 603 ft | April 25 | May 11 | October 16 | 5a |
| Cascade, IA | 20 mi | 814 ft | April 28 | May 12 | October 10 | 5a |
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
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 21 | May 13 | May 7 | April 23 | October 2 | September 20 |
| 32°F | May 12 | May 4 | April 28 | April 13 | October 11 | September 28 |
| 28°F (hard freeze) | May 3 | April 24 | April 17 | April 2 | October 21 | October 8 |
| 24°F | April 22 | April 12 | April 6 | March 21 | October 31 | October 17 |
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.