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 98229
The USDA's 2023 Plant Hardiness Zone Map puts ZIP 98229 in zone 8a (the coldest night of a typical year: 10 to 15°F).
The nearest station, Bellingham (3 mi SSW), WA, is 5 miles from the ZIP's center: its last spring frost comes after April 1 in half of years and after April 24 in one year in ten.
| Station | Distance | Elevation | Last frost (median) | 1 in 10 after | First frost (median) | Hardiness zone |
|---|---|---|---|---|---|---|
| Bellingham (3 mi SSW), WA | 5 mi | 15 ft | April 1 | April 24 | November 2 | – |
| Bellingham, WABellingham International Airport | 9 mi | 149 ft | March 31 | April 18 | October 30 | 8b |
| Sedro-Woolley, WA | 16 mi | 60 ft | March 27 | April 17 | November 6 | 8b |
| Anacortes, WA | 17 mi | 20 ft | March 8 | March 28 | November 20 | – |
| Clearbrook, WA | 18 mi | 64 ft | April 18 | May 5 | October 18 | 8b |
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 Bellingham (3 mi SSW)
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 11 | May 3 | April 27 | April 8 | October 18 | October 2 |
| 32°F | April 24 | April 8 | April 1 | March 11 | November 2 | October 15 |
| 28°F (hard freeze) | March 27 | March 15 | March 6 | February 11 | November 21 | November 1 |
| 24°F | March 10 | February 26 | February 15 | January 7 | December 9 | November 14 |
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.