Williston, North Dakota has a Cold Semi-Arid Climate climate (Köppen classification: BSk). Average annual temperatures range from 30.5 °F (low) to 54.6 °F (high). Annual precipitation averages 15 Inches. Williston is located in USDA Plant Hardiness Zone 4a. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Sep. 21 - Sep. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 2.8 °F | 22.6 °F | 0.41 in. |
| February | 7.1 °F | 27.7 °F | 0.27 in. |
| March | 18.0 °F | 40.1 °F | 0.5 in. |
| April | 30.3 °F | 55.9 °F | 1.02 in. |
| May | 41.5 °F | 67.1 °F | 2.28 in. |
| June | 51.6 °F | 76.2 °F | 2.87 in. |
| July | 57.1 °F | 84.2 °F | 2.72 in. |
| August | 54.4 °F | 84.0 °F | 1.57 in. |
| September | 44.1 °F | 73.3 °F | 1.38 in. |
| October | 32.1 °F | 57.1 °F | 0.96 in. |
| November | 18.6 °F | 39.6 °F | 0.54 in. |
| December | 8.0 °F | 27.0 °F | 0.44 in. |
| Annual | 30.5 °F | 54.6 °F | 14.96 in. |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 4a : -30°F to -25°F |
| Plant Hardiness Zone - 2012 | Zone 4a : -30°F to -25°F |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | BSk - Cold Semi-Arid Climate |