Belt, Montana has a Cold Semi-Arid Climate climate (Köppen classification: BSk). Average annual temperatures range from 32.5 °F (low) to 58.2 °F (high). Annual precipitation averages 17 Inches. Belt is located in USDA Plant Hardiness Zone 4b. 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 | 14.6 °F | 36.2 °F | 0.69 in. |
| February | 15.6 °F | 38.2 °F | 0.59 in. |
| March | 22.3 °F | 46.8 °F | 0.76 in. |
| April | 30.8 °F | 56.0 °F | 1.82 in. |
| May | 39.3 °F | 65.3 °F | 2.58 in. |
| June | 47.1 °F | 73.5 °F | 3.4 in. |
| July | 52.3 °F | 84.5 °F | 1.4 in. |
| August | 50.9 °F | 83.9 °F | 1.34 in. |
| September | 43.1 °F | 73.0 °F | 1.64 in. |
| October | 33.9 °F | 58.6 °F | 1.32 in. |
| November | 23.9 °F | 45.4 °F | 0.81 in. |
| December | 16.2 °F | 36.8 °F | 0.69 in. |
| Annual | 32.5 °F | 58.2 °F | 17.04 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 4b : -25°F to -20°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 |