Twisp, Washington has a Humid Continental Climate - Dry Cool Summer climate (Köppen classification: Dsb). Average annual temperatures range from 34.4 °F (low) to 59.6 °F (high). Annual precipitation averages 14.7 Inches. Twisp is located in USDA Plant Hardiness Zone 6a. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Sep. 21 - Sep. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 17.5 °F | 31.5 °F | 2.08 in. |
| February | 20.2 °F | 39.1 °F | 1.24 in. |
| March | 26.8 °F | 50.0 °F | 1.23 in. |
| April | 33.5 °F | 61.2 °F | 0.85 in. |
| May | 41.0 °F | 71.3 °F | 1.09 in. |
| June | 47.3 °F | 77.3 °F | 1.08 in. |
| July | 52.5 °F | 86.7 °F | 0.6 in. |
| August | 51.4 °F | 86.8 °F | 0.48 in. |
| September | 43.8 °F | 77.4 °F | 0.45 in. |
| October | 34.3 °F | 61.0 °F | 1.22 in. |
| November | 26.3 °F | 42.3 °F | 2.01 in. |
| December | 17.7 °F | 30.5 °F | 2.38 in. |
| Annual | 34.4 °F | 59.6 °F | 14.71 in. |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 6a : -10°F to -5°F |
| Plant Hardiness Zone - 2012 | Zone 5b : -15°F to -10°F |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | Dsb - Humid Continental Climate - Dry Cool Summer |