Superior, Montana has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 34.2 °F (low) to 59.2 °F (high). Annual precipitation averages 22.2 Inches. Superior is located in USDA Plant Hardiness Zone 6a. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 21.2 °F | 35.0 °F | 2.4 in. |
| February | 22.0 °F | 39.8 °F | 1.95 in. |
| March | 26.9 °F | 49.4 °F | 1.89 in. |
| April | 32.5 °F | 58.5 °F | 1.64 in. |
| May | 39.3 °F | 68.5 °F | 1.9 in. |
| June | 45.7 °F | 75.7 °F | 2.2 in. |
| July | 50.2 °F | 86.7 °F | 0.91 in. |
| August | 49.2 °F | 86.4 °F | 0.92 in. |
| September | 41.6 °F | 75.4 °F | 1.17 in. |
| October | 33.7 °F | 58.7 °F | 2.14 in. |
| November | 26.7 °F | 42.2 °F | 2.44 in. |
| December | 21.1 °F | 33.7 °F | 2.6 in. |
| Annual | 34.2 °F | 59.2 °F | 22.16 in. |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | Over 180 Days |
| Plant Hardiness Zone | Zone 6a : -10°F to -5°F |
| Plant Hardiness Zone - 2012 | Zone 6a : -10°F to -5°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |