Frost dates for Belknap Springs 8 N, OR
At Belknap Springs 8 N, the median last spring frost (32°F) is May 5 and the median first fall frost is Oct 12, for a typical growing season of 159 days. For a 90% chance that the last frost has passed, wait until May 29. Nearby ZIP codes are in USDA hardiness zones 6b to 8b.
- May 5Last spring frost (median)50% chance of 32°F after this date
- May 29Safer planting date10% chance of 32°F after this date
- Oct 12First fall frost (median)50% chance of 32°F by this date
- 159 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 | May 10 | May 30 | Jun 21 |
| 32°F | Apr 20 | May 5 | May 29 |
| 28°F | Mar 20 | Apr 12 | May 3 |
| 24°F | Feb 14 | Mar 11 | Apr 7 |
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 7 | Sep 26 | Oct 13 |
| 32°F | Sep 25 | Oct 12 | Nov 3 |
| 28°F | Oct 15 | Nov 5 | Nov 30 |
| 24°F | Nov 5 | Nov 28 | Dec 23 |
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 | 88 days | 119 days | 145 days |
| 32°F | 131 days | 159 days | 185 days |
| 28°F | 175 days | 204 days | 236 days |
| 24°F | 224 days | 259 days | 300 days |
Chance of a freeze in any year
| Temperature | Chance per year |
|---|---|
| 36°F | 100% |
| 32°F | 100% |
| 28°F | 100% |
| 24°F | 100% |
Closest ZIP codes (each is closer to another station)
| ZIP | Hardiness zone | Avg. extreme low | Distance |
|---|---|---|---|
| 97329 | 8b | 15 to 20°F | 22 km |
| 97413 | 7b | 5 to 10°F | 27 km |
| 97759 | 7a | 0 to 5°F | 31 km |
| 97488 | 8b | 15 to 20°F | 35 km |
| 97730 | 6b | -5 to 0°F | 41 km |
| 97350 | 7b | 5 to 10°F | 41 km |
| 97345 | 8b | 15 to 20°F | 45 km |
| 97709 | 6b | -5 to 0°F | 46 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 USC00350652, at 44.2867, -122.0389, elevation 656 m (2,152 ft).
- Data quality: Representative (10+ years), 22 years of freeze data.
- Average days per year at or below 32°F: 131.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- McKenzie River Ranger Station (13 km)
- Santiam Junction (18 km)
- Cougar Dam (24 km)
- Marion Forks Fish Hatchery (37 km)
- Cascadia (37 km)
- Sisters (39 km)
- Detroit Dam (52 km)
- Foster Dam (52 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.