Frost dates for Mitchell 2 E, OR
At Mitchell 2 E, the median last spring frost (32°F) is May 22 and the median first fall frost is Oct 4, for a typical growing season of 135 days. For a 90% chance that the last frost has passed, wait until Jun 11. Nearby ZIP codes are in USDA hardiness zones 6a to 7a.
- May 22Last spring frost (median)50% chance of 32°F after this date
- Jun 11Safer planting date10% chance of 32°F after this date
- Oct 4First fall frost (median)50% chance of 32°F by this date
- 135 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 27 | Jun 14 | Jun 30 |
| 32°F | May 1 | May 22 | Jun 11 |
| 28°F | Apr 11 | Apr 30 | May 18 |
| 24°F | Mar 15 | Apr 8 | May 1 |
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 1 | Sep 19 | Oct 5 |
| 32°F | Sep 16 | Oct 4 | Oct 20 |
| 28°F | Oct 4 | Oct 22 | Nov 7 |
| 24°F | Oct 18 | Nov 3 | Nov 25 |
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 | 71 days | 96 days | 120 days |
| 32°F | 108 days | 135 days | 161 days |
| 28°F | 147 days | 173 days | 201 days |
| 24°F | 179 days | 209 days | 242 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 |
|---|---|---|---|
| 97874 | 7a | 0 to 5°F | 30 km |
| 97750 | 7a | 0 to 5°F | 33 km |
| 97830 | 7a | 0 to 5°F | 45 km |
| 97848 | 7a | 0 to 5°F | 46 km |
| 97711 | 7a | 0 to 5°F | 46 km |
| 97752 | 6a | -10 to -5°F | 49 km |
| 97825 | 7a | 0 to 5°F | 53 km |
| 97751 | 6a | -10 to -5°F | 55 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 USC00355638, at 44.5681, -120.1156, elevation 1012 m (3,320 ft).
- Data quality: Representative (10+ years), 19 years of freeze data.
- Average days per year at or below 32°F: 136.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- John Day 35 WNW (37 km)
- Dayville 8 NW (37 km)
- Fossil (49 km)
- Paulina (49 km)
- Antelope 6 SSW (58 km)
- Monument 2 (62 km)
- Prineville (65 km)
- Grizzly (65 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.