Frost dates for Chelan, WA
At Chelan, the median last spring frost (32°F) is Apr 17 and the median first fall frost is Oct 22, for a typical growing season of 187 days. For a 90% chance that the last frost has passed, wait until Apr 30. Nearby ZIP codes are in USDA hardiness zones 7a to 7b.
- Apr 17Last spring frost (median)50% chance of 32°F after this date
- Apr 30Safer planting date10% chance of 32°F after this date
- Oct 22First fall frost (median)50% chance of 32°F by this date
- 187 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 1 | May 15 |
| 32°F | Apr 3 | Apr 17 | Apr 30 |
| 28°F | Mar 11 | Mar 29 | Apr 15 |
| 24°F | Feb 24 | Mar 10 | Mar 28 |
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 | Oct 1 | Oct 10 | Oct 22 |
| 32°F | Oct 9 | Oct 22 | Nov 5 |
| 28°F | Oct 21 | Nov 4 | Nov 18 |
| 24°F | Oct 30 | Nov 15 | Nov 30 |
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 | 143 days | 161 days | 177 days |
| 32°F | 170 days | 187 days | 206 days |
| 28°F | 196 days | 219 days | 242 days |
| 24°F | 223 days | 248 days | 271 days |
Chance of a freeze in any year
| Temperature | Chance per year |
|---|---|
| 36°F | 100% |
| 32°F | 100% |
| 28°F | 100% |
| 24°F | 100% |
ZIP codes whose closest station is this one
| ZIP | Hardiness zone | Avg. extreme low | Distance |
|---|---|---|---|
| 98817 | 7b | 5 to 10°F | 5 km |
| 98831 | 7a | 0 to 5°F | 15 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 USC00451350, at 47.8344, -120.0006, elevation 364 m (1,194 ft).
- Data quality: Standard (24+ years of data), 29 years of freeze data.
- Average days per year at or below 32°F: 109.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Waterville (21 km)
- Entiat Fish Hatchery (28 km)
- Methow 2 S (30 km)
- Chief Joseph Dam (32 km)
- Plain (48 km)
- Wenatchee (51 km)
- Wenatchee Pangborn Airport (51 km)
- Leavenworth 3 S (59 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.