Rollins, Montana has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 33.7 °F (low) to 56.1 °F (high). Annual precipitation averages 16.3 Inches. Rollins 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 Sep. 21 - Sep. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 19.5 °F | 33.1 °F | 1.21 in. |
| February | 20.2 °F | 36.8 °F | 0.99 in. |
| March | 25.8 °F | 45.9 °F | 1.07 in. |
| April | 31.9 °F | 55.2 °F | 1.62 in. |
| May | 39.5 °F | 65.0 °F | 1.55 in. |
| June | 45.9 °F | 71.4 °F | 2.62 in. |
| July | 50.6 °F | 82.5 °F | 1.17 in. |
| August | 49.1 °F | 82.4 °F | 1.0 in. |
| September | 41.8 °F | 71.3 °F | 1.17 in. |
| October | 33.0 °F | 55.8 °F | 1.53 in. |
| November | 26.2 °F | 41.3 °F | 1.09 in. |
| December | 20.4 °F | 33.0 °F | 1.25 in. |
| Annual | 33.7 °F | 56.1 °F | 16.27 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 6a : -10°F to -5°F |
| Plant Hardiness Zone - 2012 | Zone 5b : -15°F to -10°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |