Frost dates for Illahe, OR
At Illahe, the median last spring frost (32°F) is Mar 30 and the median first fall frost is Nov 17, for a typical growing season of 233 days. For a 90% chance that the last frost has passed, wait until May 2. Nearby ZIP codes are in USDA hardiness zone 9a.
- Mar 30Last spring frost (median)50% chance of 32°F after this date
- May 2Safer planting date10% chance of 32°F after this date
- Nov 17First fall frost (median)50% chance of 32°F by this date
- 233 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 14 | May 6 | May 25 |
| 32°F | Feb 20 | Mar 30 | May 2 |
| 28°F | Dec 15 | Feb 1 | Mar 18 |
| 24°F | Dec 2 | Dec 29 | Jan 26 |
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 1 | Oct 26 | Nov 16 |
| 32°F | Oct 20 | Nov 17 | Dec 15 |
| 28°F | Nov 8 | Dec 10 | Jan 26 |
| 24°F | Nov 29 | Dec 19 | Jan 17 |
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 | 142 days | 173 days | 205 days |
| 32°F | 192 days | 233 days | 285 days |
| 28°F | 266 days | 315 days | 364 days |
| 24°F | 331 days | 365 days | 365 days |
Chance of a freeze in any year
| Temperature | Chance per year |
|---|---|
| 36°F | 100% |
| 32°F | 100% |
| 28°F | 92% |
| 24°F | 45% |
ZIP codes whose closest station is this one
| ZIP | Hardiness zone | Avg. extreme low | Distance |
|---|---|---|---|
| 97406 | 9a | 20 to 25°F | 3 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 USC00354133, at 42.6286, -124.0575, elevation 106 m (348 ft).
- Data quality: Representative (10+ years), 12 years of freeze data.
- Average days per year at or below 32°F: 19.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Powers (29 km)
- Port Orford #2 (39 km)
- Gold Beach Ranger Station (39 km)
- Langlois #2 (46 km)
- Sexton Summit (57 km)
- Cave Junction 1 WNW (62 km)
- Coquille City (63 km)
- Bandon 2 NNE (64 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.