Frost dates for Darrington 21 NNE, WA
At Darrington 21 NNE, the median last spring frost (32°F) is Apr 16 and the median first fall frost is Oct 25, for a typical growing season of 192 days. For a 90% chance that the last frost has passed, wait until May 6. Nearby ZIP codes are in USDA hardiness zone 7a.
- Apr 16Last spring frost (median)50% chance of 32°F after this date
- May 6Safer planting date10% chance of 32°F after this date
- Oct 25First fall frost (median)50% chance of 32°F by this date
- 192 daysGrowing season (median)between 32°F freezes
Last spring frost dates
The chance that the temperature drops to the threshold after each date.
| Temperature | 90% chance later | 50% chance later | 10% chance later |
|---|---|---|---|
| 36°F | Apr 19 | May 6 | May 21 |
| 32°F | Mar 26 | Apr 16 | May 6 |
| 28°F | Feb 27 | Mar 19 | Apr 6 |
| 24°F | Jan 2 | Feb 18 | Mar 14 |
First fall frost dates
The chance that the temperature has dropped to the threshold by each date.
| Temperature | 10% chance by | 50% chance by | 90% chance by |
|---|---|---|---|
| 36°F | Sep 27 | Oct 10 | Oct 25 |
| 32°F | Oct 10 | Oct 25 | Nov 11 |
| 28°F | Oct 22 | Nov 11 | Dec 6 |
| 24°F | Nov 11 | Dec 6 | Jan 9 |
Growing season length
Days between the last spring and first fall freeze, as the length reached in 9, 5 and 1 out of 10 years.
| Temperature | 9 in 10 years at least | 5 in 10 years at least | 1 in 10 years at least |
|---|---|---|---|
| 36°F | 136 days | 157 days | 181 days |
| 32°F | 166 days | 192 days | 219 days |
| 28°F | 208 days | 237 days | 270 days |
| 24°F | 253 days | 295 days | 340 days |
Chance of a freeze in any year
| Temperature | Chance per year |
|---|---|
| 36°F | 100% |
| 32°F | 100% |
| 28°F | 100% |
| 24°F | 98% |
ZIP codes whose closest station is this one
| ZIP | Hardiness zone | Avg. extreme low | Distance |
|---|---|---|---|
| 98267 | 7a | 0 to 5°F | 21 km |
Not the official USDA Plant Hardiness Zone Map. Zones shown here are the values published in the USDA-ARS / Oregon State University PRISM Group 2023 ZIP code tables, shown unaltered. For the official interactive map, visit planthardiness.ars.usda.gov.
About this station
- NOAA station ID USW00004223, at 48.5406, -121.4461, elevation 124 m (407 ft).
- Data quality: Representative (10+ years), 18 years of freeze data.
- Average days per year at or below 32°F: 79.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Newhalem (21 km)
- Concrete Ppl Fish Station (22 km)
- Upper Baker Dam (22 km)
- Diablo Dam (29 km)
- Darrington Ranger Station (33 km)
- Ross Dam (34 km)
- Stehekin 4 NW (57 km)
- Sedro-Woolley (58 km)
Sources
- NOAA National Centers for Environmental Information, U.S. Climate Normals 1991–2020, annual/seasonal normals by station (version 1.0.1), file dated June 27, 2023; documentation.
- USDA Agricultural Research Service and PRISM Group, Oregon State University, 2023 Plant Hardiness Zone Map ZIP code tables (CONUS, Alaska, Hawaii, Puerto Rico), files dated November 17, 2023. Data © PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed November 1, 2026. Official map: planthardiness.ars.usda.gov.
- U.S. Census Bureau, 2024 Gazetteer ZIP Code Tabulation Areas file, dated August 30, 2024 (ZIP centroids used to find the nearest station).
Freeze dates are 30-year probabilities, not forecasts. Check your local forecast before planting tender plants.