Frost dates for Pendleton WFO, OR
At Pendleton WFO, the median last spring frost (32°F) is Apr 14 and the median first fall frost is Oct 22, for a typical growing season of 188 days. For a 90% chance that the last frost has passed, wait until May 5. Nearby ZIP codes are in USDA hardiness zones 6b to 7a.
- Apr 14Last spring frost (median)50% chance of 32°F after this date
- May 5Safer planting date10% chance of 32°F after this date
- Oct 22First fall frost (median)50% chance of 32°F by this date
- 188 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 17 | May 2 | May 19 |
| 32°F | Mar 24 | Apr 14 | May 5 |
| 28°F | Mar 3 | Mar 23 | Apr 13 |
| 24°F | Feb 10 | Mar 1 | Mar 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 | Sep 27 | Oct 10 | Oct 25 |
| 32°F | Oct 7 | Oct 22 | Nov 5 |
| 28°F | Oct 18 | Nov 2 | Nov 20 |
| 24°F | Oct 28 | Nov 14 | Dec 3 |
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 | 137 days | 160 days | 181 days |
| 32°F | 164 days | 188 days | 214 days |
| 28°F | 197 days | 225 days | 251 days |
| 24°F | 229 days | 256 days | 286 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 |
|---|---|---|---|
| 97801 | 7a | 0 to 5°F | 3 km |
| 97835 | 7a | 0 to 5°F | 24 km |
| 97875 | 7a | 0 to 5°F | 27 km |
| 97826 | 7a | 0 to 5°F | 30 km |
| 97813 | 7a | 0 to 5°F | 31 km |
| 97868 | 6b | -5 to 0°F | 31 km |
| 97810 | 7a | 0 to 5°F | 35 km |
| 97859 | 6b | -5 to 0°F | 38 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 USC00356550, at 45.6911, -118.8522, elevation 460 m (1,510 ft).
- Data quality: Representative (10+ years), 18 years of freeze data.
- Average days per year at or below 32°F: 92.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Pendleton (0 km)
- Pendleton Dwtn (5 km)
- Pendleton Branch Exp. Station (18 km)
- Pilot Rock 1 SE (24 km)
- Hermiston Muni Airport (35 km)
- Meacham (39 km)
- Hermiston 2 NW (40 km)
- McNary Dam #2 (43 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.