Wasco, Oregon has a Humid Continental Climate - Dry Cool Summer climate (Köppen classification: Dsb). Average annual temperatures range from 39.9 °F (low) to 62.7 °F (high). Annual precipitation averages 12.1 Inches. Wasco is located in USDA Plant Hardiness Zone 7a. 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 | 28.2 °F | 40.7 °F | 1.87 in. |
| February | 29.6 °F | 45.8 °F | 1.22 in. |
| March | 33.3 °F | 53.9 °F | 1.0 in. |
| April | 37.6 °F | 61.0 °F | 0.95 in. |
| May | 43.7 °F | 69.9 °F | 0.9 in. |
| June | 49.4 °F | 76.6 °F | 0.67 in. |
| July | 54.4 °F | 86.5 °F | 0.2 in. |
| August | 54.2 °F | 86.4 °F | 0.23 in. |
| September | 48.3 °F | 78.5 °F | 0.39 in. |
| October | 39.1 °F | 64.0 °F | 1.09 in. |
| November | 32.7 °F | 49.0 °F | 1.63 in. |
| December | 28.0 °F | 39.9 °F | 1.95 in. |
| Annual | 39.9 °F | 62.7 °F | 12.1 in. |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| 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 | Normal |
| Köppen Climate Classification | Dsb - Humid Continental Climate - Dry Cool Summer |