Clatskanie, Oregon has a Warm-Summer Mediterranean Climate climate (Köppen classification: Csb). Average annual temperatures range from 5.8 °C (low) to 15.8 °C (high). Annual precipitation averages 1400.6 Millimeters. Clatskanie is located in USDA Plant Hardiness Zone 8b. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 1.5 °C | 8.1 °C | 211.07 mm |
| February | 1.2 °C | 10.1 °C | 143.51 mm |
| March | 2.6 °C | 12.4 °C | 156.46 mm |
| April | 4.2 °C | 14.8 °C | 110.49 mm |
| May | 7.2 °C | 18.2 °C | 68.33 mm |
| June | 9.6 °C | 20.3 °C | 44.96 mm |
| July | 11.7 °C | 23.7 °C | 14.99 mm |
| August | 11.7 °C | 24.4 °C | 17.27 mm |
| September | 9.4 °C | 22.3 °C | 53.09 mm |
| October | 6.1 °C | 16.3 °C | 119.13 mm |
| November | 3.3 °C | 11.1 °C | 220.22 mm |
| December | 1.3 °C | 7.7 °C | 241.05 mm |
| Annual | 5.8 °C | 15.8 °C | 1400.57 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 50-75 Days |
| Plant Hardiness Zone | Zone 8b : -9.4°C to -6.7°C |
| Plant Hardiness Zone - 2012 | Zone 8b : -9.4°C to -6.7°C |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Csb - Warm-Summer Mediterranean Climate |