Butte, Montana has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 25.9 °F (low) to 53.6 °F (high). Annual precipitation averages 11.9 Inches. Butte is located in USDA Plant Hardiness Zone 4a. The growing season typically runs from the last frost around Jun. 11 - Jun. 20 through the first frost around Aug. 21 - Aug. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 8.4 °F | 31.7 °F | 0.44 in. |
| February | 10.3 °F | 34.6 °F | 0.44 in. |
| March | 18.6 °F | 43.1 °F | 0.69 in. |
| April | 25.5 °F | 50.7 °F | 1.29 in. |
| May | 33.3 °F | 60.1 °F | 1.86 in. |
| June | 40.0 °F | 69.0 °F | 2.4 in. |
| July | 45.1 °F | 80.5 °F | 0.95 in. |
| August | 43.1 °F | 79.5 °F | 0.87 in. |
| September | 35.9 °F | 68.9 °F | 1.02 in. |
| October | 26.6 °F | 54.5 °F | 0.92 in. |
| November | 16.3 °F | 40.3 °F | 0.55 in. |
| December | 8.1 °F | 30.8 °F | 0.51 in. |
| Annual | 25.9 °F | 53.6 °F | 11.94 in. |
| Average First Frost Date | Aug. 21 - Aug. 31 |
| Average Last Frost Date | Jun. 11 - Jun. 20 |
| Average Days With Frost | Over 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 | Severe Drought |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |