| 2023 Hardiness Zone: | Zone 8b: 15°F to 20°F Zone 8a: 10°F to 15°F |
| 2012 Hardiness Zone: | Zone 8a: 10°F to 15°F Zone 7b: 5°F to 10°F |
| 1990 Hardiness Zone: | Zone 7b: 5F to 10F |
| Average First Frost Date: | Oct. 1 - Oct. 10 |
| Average Last Frost Date: | May 21 - May 31 |
| Koppen-Geiger Climate Zone: | Csb - Warm-Summer Mediterranean Climate |
| Ecoregion: | 1f - Willapa Hills |
| Heat Zone Days: | Rare Over 86°F |
Annual Climate Data for ZIP Code 97064 - Vernonia, OR | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 30 | 31 | 33 | 36 | 40 | 45 | 48 | 47 | 43 | 38 | 34 | 30 | 38 |
| Avg Max Temp (°F) | 44 | 49 | 54 | 58 | 64 | 69 | 75 | 76 | 73 | 62 | 50 | 44 | 60 |
| Avg Precip (In.) | 8.31 | 6.44 | 5.7 | 3.82 | 2.38 | 1.62 | .6 | .83 | 1.68 | 4.01 | 7.79 | 8.58 | 51.77 |