Mount Vista, Washington has a Warm-Summer Mediterranean Climate climate (Köppen classification: Csb). Average annual temperatures range from 6.1 °C (low) to 16.8 °C (high). Annual precipitation averages 1146.5 Millimeters. Mount Vista is located in USDA Plant Hardiness Zone 8b. The growing season typically runs from the last frost around Apr. 11 - Apr. 20 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 1.3 °C | 8.1 °C | 163.32 mm |
| February | 1.3 °C | 10.3 °C | 117.6 mm |
| March | 2.8 °C | 12.9 °C | 128.27 mm |
| April | 4.7 °C | 15.6 °C | 92.96 mm |
| May | 7.8 °C | 19.5 °C | 68.83 mm |
| June | 10.1 °C | 22.1 °C | 50.29 mm |
| July | 12.3 °C | 26.3 °C | 12.95 mm |
| August | 12.2 °C | 26.9 °C | 16 mm |
| September | 9.7 °C | 23.8 °C | 45.47 mm |
| October | 6.2 °C | 17.3 °C | 105.16 mm |
| November | 3.3 °C | 11.3 °C | 161.29 mm |
| December | 1.2 °C | 7.7 °C | 184.4 mm |
| Annual | 6.1 °C | 16.8 °C | 1146.54 mm |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 50-75 Days |
| Plant Hardiness Zone | Zone 8b : -9.4°C to -6.7°C |
| Plant Hardiness Zone - 2012 | Zone 8b : -9.4°C to -6.7°C |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Csb - Warm-Summer Mediterranean Climate |