Washington, Utah has a Cold Desert Climate climate (Köppen classification: BWk). Average annual temperatures range from 9.8 °C (low) to 25.3 °C (high). Annual precipitation averages 218.7 Millimeters. Washington is located in USDA Plant Hardiness Zone 8b. The growing season typically runs from the last frost around Mar. 1 - Mar. 10 through the first frost around Nov. 11 - Nov. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -0.4 °C | 12.7 °C | 29.72 mm |
| February | 1.6 °C | 15.2 °C | 34.8 mm |
| March | 4.9 °C | 19.8 °C | 24.89 mm |
| April | 8.2 °C | 23.8 °C | 16.51 mm |
| May | 13.1 °C | 29.6 °C | 9.14 mm |
| June | 18 °C | 35.8 °C | 3.81 mm |
| July | 22.3 °C | 38.8 °C | 13.97 mm |
| August | 21.6 °C | 37.7 °C | 16.51 mm |
| September | 16.7 °C | 33.6 °C | 14.22 mm |
| October | 9.8 °C | 26.2 °C | 17.53 mm |
| November | 3.1 °C | 18.1 °C | 18.03 mm |
| December | -0.8 °C | 11.8 °C | 19.56 mm |
| Annual | 9.8 °C | 25.3 °C | 218.69 mm |
| Average First Frost Date | Nov. 11 - Nov. 20 |
| Average Last Frost Date | Mar. 1 - Mar. 10 |
| Average Days With Frost | 50-75 Days |
| Plant Hardiness Zone | Zone 8b : -9.4°C to -6.7°C |
| Plant Hardiness Zone - 2012 | Zone 8a : -12.2°C to -9.4°C |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | BWk - Cold Desert Climate |