Frost dates for Corvallis Water Bureau, OR
At Corvallis Water Bureau, the median last spring frost (32°F) is May 15 and the median first fall frost is Oct 8, for a typical growing season of 145 days. For a 90% chance that the last frost has passed, wait until Jun 2. Nearby ZIP codes are in USDA hardiness zone 8b.
- May 15Last spring frost (median)50% chance of 32°F after this date
- Jun 2Safer planting date10% chance of 32°F after this date
- Oct 8First fall frost (median)50% chance of 32°F by this date
- 145 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 21 | Jun 8 | Jun 26 |
| 32°F | Apr 28 | May 15 | Jun 2 |
| 28°F | Apr 2 | Apr 25 | May 10 |
| 24°F | Feb 19 | Mar 22 | Apr 20 |
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 3 | Sep 19 | Oct 5 |
| 32°F | Sep 24 | Oct 8 | Oct 26 |
| 28°F | Oct 9 | Oct 28 | Nov 13 |
| 24°F | Oct 29 | Nov 14 | Dec 7 |
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 | 76 days | 102 days | 128 days |
| 32°F | 119 days | 145 days | 172 days |
| 28°F | 159 days | 186 days | 214 days |
| 24°F | 203 days | 237 days | 280 days |
Chance of a freeze in any year
| Temperature | Chance per year |
|---|---|
| 36°F | 100% |
| 32°F | 100% |
| 28°F | 100% |
| 24°F | 100% |
ZIP codes whose closest station is this one
| ZIP | Hardiness zone | Avg. extreme low | Distance |
|---|---|---|---|
| 97370 | 8b | 15 to 20°F | 7 km |
| 97326 | 8b | 15 to 20°F | 22 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 USC00351877, at 44.5078, -123.4575, elevation 180 m (592 ft).
- Data quality: Representative (10+ years), 18 years of freeze data.
- Average days per year at or below 32°F: 83.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Corvallis 10 SSW (14 km)
- Corvallis State Univ (25 km)
- Alsea Fh (fall Creek) (26 km)
- Falls City 2 SSW (36 km)
- Lebanon (44 km)
- Eugene Mahlon Sweet Airport (46 km)
- Laurel Mountain (47 km)
- Newport 1 SE (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.