Elliston, Montana has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 26.5 °F (low) to 54 °F (high). Annual precipitation averages 17.4 Inches. Elliston is located in USDA Plant Hardiness Zone 4b. The growing season typically runs from the last frost around May 21 - May 31 through the first frost around Sep.1 - Sep. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 10.9 °F | 32.8 °F | 1.06 in. |
| February | 12.0 °F | 35.5 °F | 0.94 in. |
| March | 19.3 °F | 43.8 °F | 1.12 in. |
| April | 25.7 °F | 51.2 °F | 1.72 in. |
| May | 33.5 °F | 60.5 °F | 2.12 in. |
| June | 39.5 °F | 69.0 °F | 3.06 in. |
| July | 44.5 °F | 80.5 °F | 1.39 in. |
| August | 42.4 °F | 79.9 °F | 1.3 in. |
| September | 35.7 °F | 68.9 °F | 1.35 in. |
| October | 26.3 °F | 54.0 °F | 1.35 in. |
| November | 17.4 °F | 40.5 °F | 1.11 in. |
| December | 10.4 °F | 31.9 °F | 0.88 in. |
| Annual | 26.5 °F | 54 °F | 17.4 in. |
| Average First Frost Date | Sep.1 - Sep. 10 |
| Average Last Frost Date | May 21 - May 31 |
| Average Days With Frost | Over 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 | Abnormally Dry |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |