Townsend, Montana has a Cold Semi-Arid Climate climate (Köppen classification: BSk). Average annual temperatures range from 31.8 °F (low) to 58.8 °F (high). Annual precipitation averages 10.4 Inches. Townsend 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.11 - Sep. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 13.4 °F | 34.1 °F | 0.27 in. |
| February | 17.1 °F | 39.6 °F | 0.23 in. |
| March | 23.2 °F | 49.2 °F | 0.42 in. |
| April | 30.9 °F | 58.3 °F | 0.87 in. |
| May | 39.3 °F | 67.1 °F | 1.71 in. |
| June | 46.4 °F | 74.9 °F | 2.52 in. |
| July | 51.7 °F | 85.2 °F | 1.19 in. |
| August | 49.2 °F | 84.4 °F | 1.09 in. |
| September | 41.6 °F | 73.9 °F | 0.8 in. |
| October | 31.9 °F | 59.8 °F | 0.61 in. |
| November | 22.5 °F | 44.6 °F | 0.37 in. |
| December | 14.8 °F | 34.7 °F | 0.33 in. |
| Annual | 31.8 °F | 58.8 °F | 10.41 in. |
| Average First Frost Date | Sep.11 - Sep. 20 |
| 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 4b : -25°F to -20°F |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | BSk - Cold Semi-Arid Climate |