Wishram, Washington has a Humid Continental Climate - Dry Cool Summer climate (Köppen classification: Dsb). Average annual temperatures range from 6.4 °C (low) to 18.3 °C (high). Annual precipitation averages 311.2 Millimeters. Wishram is located in USDA Plant Hardiness Zone 8a. 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 | -0.2 °C | 5.9 °C | 54.86 mm |
| February | 0.3 °C | 9.1 °C | 33.53 mm |
| March | 2.4 °C | 13.6 °C | 29.46 mm |
| April | 5.2 °C | 17.7 °C | 18.54 mm |
| May | 8.8 °C | 22.6 °C | 18.03 mm |
| June | 11.9 °C | 25.8 °C | 10.67 mm |
| July | 15.2 °C | 30.9 °C | 4.32 mm |
| August | 15 °C | 31.2 °C | 4.83 mm |
| September | 10.8 °C | 26.8 °C | 8.13 mm |
| October | 6 °C | 19.1 °C | 21.59 mm |
| November | 2.1 °C | 10.7 °C | 44.96 mm |
| December | -0.2 °C | 5.8 °C | 62.23 mm |
| Annual | 6.4 °C | 18.3 °C | 311.15 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 75-100 Days |
| Plant Hardiness Zone | Zone 8a : -12.2°C to -9.4°C |
| Plant Hardiness Zone - 2012 | Zone 7b : -15°C to -12.2°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dsb - Humid Continental Climate - Dry Cool Summer |