Vernal, Utah has a Cold Semi-Arid Climate climate (Köppen classification: BSk). Average annual temperatures range from 33.4 °F (low) to 60.8 °F (high). Annual precipitation averages 8 Inches. Vernal is located in USDA Plant Hardiness Zone 6a. The growing season typically runs from the last frost around May 11 - May 20 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 9.1 °F | 30.0 °F | 0.7 in. |
| February | 15.5 °F | 38.0 °F | 0.53 in. |
| March | 25.9 °F | 52.3 °F | 0.61 in. |
| April | 32.8 °F | 60.9 °F | 0.62 in. |
| May | 41.3 °F | 70.5 °F | 1.02 in. |
| June | 49.6 °F | 82.3 °F | 0.39 in. |
| July | 56.5 °F | 89.4 °F | 0.3 in. |
| August | 54.6 °F | 86.5 °F | 0.76 in. |
| September | 45.5 °F | 78.0 °F | 1.05 in. |
| October | 34.1 °F | 62.6 °F | 0.94 in. |
| November | 23.3 °F | 47.0 °F | 0.46 in. |
| December | 12.0 °F | 32.1 °F | 0.65 in. |
| Annual | 33.4 °F | 60.8 °F | 8.03 in. |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 11 - May 20 |
| 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 | BSk - Cold Semi-Arid Climate |