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 97401
The USDA's 2023 Plant Hardiness Zone Map puts ZIP 97401 in zone 8b (the coldest night of a typical year: 15 to 20°F).
The nearest station, Eugene, OR, is 8 miles from the ZIP's center: its last spring frost comes after April 11 in half of years and after May 9 in one year in ten. By the USDA's method its plant hardiness zone is 8b.
| Station | Distance | Elevation | Last frost (median) | 1 in 10 after | First frost (median) | Hardiness zone |
|---|---|---|---|---|---|---|
| Eugene, OREugene-Mahlon Sweet Field | 8 mi | 353 ft | April 11 | May 9 | October 23 | 8b |
| Fern Ridge-Veneta, OR | 14 mi | 485 ft | April 18 | May 5 | October 25 | – |
| Lookout Point Dam, OR | 19 mi | 712 ft | March 7 | April 2 | November 27 | 9a |
| Cottage Grove, OR2 mi E | 19 mi | 595 ft | April 24 | May 10 | October 25 | 8b |
| Leaburg (1 mi SW), OR | 20 mi | 675 ft | April 3 | May 2 | November 11 | 9a |
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 Eugene
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 8 | May 25 | May 15 | April 24 | October 7 | September 18 |
| 32°F | May 9 | April 25 | April 11 | March 15 | October 23 | October 6 |
| 28°F (hard freeze) | March 30 | March 14 | March 3 | February 2 | November 11 | October 20 |
| 24°F | February 27 | February 17 | February 1 | December 21 | December 5 | November 2 |
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.