Yacolt, Washington has a Warm-Summer Mediterranean Climate climate (Köppen classification: Csb). Average annual temperatures range from 41.3 °F (low) to 61.4 °F (high). Annual precipitation averages 72.3 Inches. Yacolt 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. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 32.8 °F | 44.0 °F | 10.07 in. |
| February | 33.1 °F | 48.0 °F | 7.46 in. |
| March | 35.3 °F | 53.2 °F | 8.12 in. |
| April | 38.6 °F | 59.6 °F | 6.06 in. |
| May | 44.1 °F | 67.9 °F | 4.41 in. |
| June | 48.3 °F | 71.4 °F | 3.05 in. |
| July | 52.1 °F | 80.2 °F | 0.84 in. |
| August | 52.2 °F | 81.0 °F | 1.08 in. |
| September | 47.9 °F | 75.0 °F | 3.01 in. |
| October | 42.0 °F | 62.3 °F | 6.59 in. |
| November | 36.7 °F | 50.3 °F | 10.38 in. |
| December | 32.6 °F | 43.3 °F | 11.21 in. |
| Annual | 41.3 °F | 61.4 °F | 72.28 in. |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 50-75 Days |
| Plant Hardiness Zone | Zone 8b : 15°F to 20°F |
| Plant Hardiness Zone - 2012 | Zone 8a : 10°F to 15°F |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Csb - Warm-Summer Mediterranean Climate |