Frost dates for Cougar Dam, OR
At Cougar Dam, the median last spring frost (32°F) is Mar 2 and the median first fall frost is Nov 30, for a typical growing season of 274 days. For a 90% chance that the last frost has passed, wait until Mar 27. Nearby ZIP codes are in USDA hardiness zone 8b.
- Mar 2Last spring frost (median)50% chance of 32°F after this date
- Mar 27Safer planting date10% chance of 32°F after this date
- Nov 30First fall frost (median)50% chance of 32°F by this date
- 274 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 | Mar 3 | Mar 31 | Apr 29 |
| 32°F | Jan 24 | Mar 2 | Mar 27 |
| 28°F | Dec 17 | Feb 1 | Mar 7 |
| 24°F | Dec 4 | Jan 10 | Feb 22 |
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 20 | Nov 11 | Dec 3 |
| 32°F | Nov 3 | Nov 30 | Dec 28 |
| 28°F | Nov 14 | Dec 15 | Jan 27 |
| 24°F | Nov 24 | Dec 24 | Feb 14 |
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 | 188 days | 224 days | 261 days |
| 32°F | 236 days | 274 days | 318 days |
| 28°F | 274 days | 322 days | 365 days |
| 24°F | 313 days | 358 days | 365 days |
Chance of a freeze in any year
| Temperature | Chance per year |
|---|---|
| 36°F | 100% |
| 32°F | 100% |
| 28°F | 90% |
| 24°F | 57% |
ZIP codes whose closest station is this one
| ZIP | Hardiness zone | Avg. extreme low | Distance |
|---|---|---|---|
| 97488 | 8b | 15 to 20°F | 14 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 USC00351914, at 44.1308, -122.2419, elevation 384 m (1,260 ft).
- Data quality: Representative (10+ years), 12 years of freeze data.
- Average days per year at or below 32°F: 48.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- McKenzie River Ranger Station (11 km)
- Belknap Springs 8 N (24 km)
- Cascadia (35 km)
- Leaburg 1 SW (36 km)
- Santiam Junction (41 km)
- Oakridge Fish Hatchery (46 km)
- Foster Dam (47 km)
- Lookout Point Dam (48 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.