Belle Fourche, South Dakota has a Cold Semi-Arid Climate climate (Köppen classification: BSk). Average annual temperatures range from 33.8 °F (low) to 59.7 °F (high). Annual precipitation averages 18 Inches. Belle Fourche is located in USDA Plant Hardiness Zone 5a. The growing season typically runs from the last frost around May 11 - May 20 through the first frost around Sep. 21 - Sep. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 12.2 °F | 35.2 °F | 0.44 in. |
| February | 14.6 °F | 37.6 °F | 0.62 in. |
| March | 23.0 °F | 48.0 °F | 1.09 in. |
| April | 31.6 °F | 57.4 °F | 2.0 in. |
| May | 42.1 °F | 66.7 °F | 3.18 in. |
| June | 51.9 °F | 77.9 °F | 3.0 in. |
| July | 58.2 °F | 86.6 °F | 1.98 in. |
| August | 56.2 °F | 86.1 °F | 1.46 in. |
| September | 46.1 °F | 76.3 °F | 1.35 in. |
| October | 33.6 °F | 61.1 °F | 1.69 in. |
| November | 22.5 °F | 46.9 °F | 0.57 in. |
| December | 13.8 °F | 36.9 °F | 0.64 in. |
| Annual | 33.8 °F | 59.7 °F | 18.02 in. |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| Average Last Frost Date | May 11 - May 20 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 5a : -20°F to -15°F |
| Plant Hardiness Zone - 2012 | Zone 4b : -25°F to -20°F |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | BSk - Cold Semi-Arid Climate |