Frost dates for Dorena, OR
At Dorena, the median last spring frost (32°F) is Apr 16 and the median first fall frost is Oct 28, for a typical growing season of 194 days. For a 90% chance that the last frost has passed, wait until May 11. Nearby ZIP codes are in USDA hardiness zones 8b to 9a.
- Apr 16Last spring frost (median)50% chance of 32°F after this date
- May 11Safer planting date10% chance of 32°F after this date
- Oct 28First fall frost (median)50% chance of 32°F by this date
- 194 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 20 | May 9 | Jun 2 |
| 32°F | Mar 24 | Apr 16 | May 11 |
| 28°F | Feb 12 | Mar 12 | Apr 13 |
| 24°F | Dec 23 | Feb 14 | Mar 8 |
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 14 | Oct 5 | Oct 29 |
| 32°F | Oct 4 | Oct 28 | Nov 23 |
| 28°F | Oct 24 | Nov 21 | Dec 23 |
| 24°F | Nov 6 | Dec 17 | Feb 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 | 117 days | 149 days | 179 days |
| 32°F | 157 days | 194 days | 228 days |
| 28°F | 209 days | 252 days | 296 days |
| 24°F | 263 days | 310 days | 360 days |
Chance of a freeze in any year
| Temperature | Chance per year |
|---|---|
| 36°F | 100% |
| 32°F | 100% |
| 28°F | 100% |
| 24°F | 91% |
Closest ZIP codes (each is closer to another station)
| ZIP | Hardiness zone | Avg. extreme low | Distance |
|---|---|---|---|
| 97424 | 8b | 15 to 20°F | 8 km |
| 97431 | 9a | 20 to 25°F | 14 km |
| 97426 | 8b | 15 to 20°F | 14 km |
| 97452 | 9a | 20 to 25°F | 20 km |
| 97455 | 8b | 15 to 20°F | 21 km |
| 97405 | 8b | 15 to 20°F | 25 km |
| 97434 | 8b | 15 to 20°F | 28 km |
| 97451 | 8b | 15 to 20°F | 29 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 USC00352374, at 43.7822, -122.9631, elevation 250 m (820 ft).
- Data quality: Standard (24+ years of data), 27 years of freeze data.
- Average days per year at or below 32°F: 62.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Cottage Grove 2e (5 km)
- Cottage Grove Dam (10 km)
- Lookout Point Dam (22 km)
- Drain (32 km)
- Leaburg 1 SW (42 km)
- Oakridge Fish Hatchery (42 km)
- Eugene Mahlon Sweet Airport (44 km)
- Fern Ridge-Veneta (44 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.