Nespelem, Washington has a Humid Continental Climate - Dry Cool Summer climate (Köppen classification: Dsb). Average annual temperatures range from 2.4 °C (low) to 15.7 °C (high). Annual precipitation averages 350.5 Millimeters. Nespelem is located in USDA Plant Hardiness Zone 6b. 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 | -5.9 °C | 1 °C | 40.39 mm |
| February | -4.9 °C | 4.5 °C | 26.16 mm |
| March | -1.8 °C | 10.4 °C | 36.58 mm |
| April | 1.3 °C | 15.7 °C | 29.72 mm |
| May | 5.6 °C | 21.1 °C | 35.56 mm |
| June | 8.8 °C | 25.2 °C | 28.19 mm |
| July | 12.2 °C | 30.9 °C | 13.46 mm |
| August | 12.2 °C | 30.7 °C | 10.92 mm |
| September | 7.9 °C | 25.3 °C | 11.68 mm |
| October | 1.9 °C | 16.3 °C | 32.51 mm |
| November | -2.3 °C | 6.7 °C | 36.32 mm |
| December | -5.8 °C | 1 °C | 49.02 mm |
| Annual | 2.4 °C | 15.7 °C | 350.51 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 6b : -20.6°C to -17.8°C |
| Plant Hardiness Zone - 2012 | Zone 6a : -23.3°C to -20.6°C |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Dsb - Humid Continental Climate - Dry Cool Summer |