Oroville, Washington has a Cold Semi-Arid Climate climate (Köppen classification: BSk). Average annual temperatures range from 39.8 °F (low) to 61.6 °F (high). Annual precipitation averages 14 Inches. Oroville is located in USDA Plant Hardiness Zone 7a. The growing season typically runs from the last frost around Apr. 11 - Apr. 20 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 25.1 °F | 34.7 °F | 1.67 in. |
| February | 26.5 °F | 41.7 °F | 0.89 in. |
| March | 31.8 °F | 53.0 °F | 1.21 in. |
| April | 37.9 °F | 63.4 °F | 0.93 in. |
| May | 45.9 °F | 73.1 °F | 1.15 in. |
| June | 52.6 °F | 79.2 °F | 1.96 in. |
| July | 57.8 °F | 87.9 °F | 0.95 in. |
| August | 56.5 °F | 87.5 °F | 0.58 in. |
| September | 47.9 °F | 76.9 °F | 0.51 in. |
| October | 39.0 °F | 61.2 °F | 1.0 in. |
| November | 31.4 °F | 45.1 °F | 1.32 in. |
| December | 25.6 °F | 35.1 °F | 1.81 in. |
| Annual | 39.8 °F | 61.6 °F | 13.98 in. |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 100-125 Days |
| Plant Hardiness Zone | Zone 7a : 0°F to 5°F |
| Plant Hardiness Zone - 2012 | Zone 7a : 0°F to 5°F |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | BSk - Cold Semi-Arid Climate |