Toston, Montana has a Cold Semi-Arid Climate climate (Köppen classification: BSk). Average annual temperatures range from -0.9 °C (low) to 14.9 °C (high). Annual precipitation averages 305.5 Millimeters. Toston 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 | -10.8 °C | 1.3 °C | 9.4 mm |
| February | -8.7 °C | 3.8 °C | 6.6 mm |
| March | -5.4 °C | 9.4 °C | 18.03 mm |
| April | -1.3 °C | 14.7 °C | 28.7 mm |
| May | 3.4 °C | 19.5 °C | 48.26 mm |
| June | 7.1 °C | 23.9 °C | 66.29 mm |
| July | 9.7 °C | 29.6 °C | 29.97 mm |
| August | 8.1 °C | 29 °C | 28.19 mm |
| September | 4.2 °C | 23.4 °C | 23.62 mm |
| October | -0.9 °C | 15.6 °C | 20.83 mm |
| November | -6.2 °C | 7.1 °C | 13.97 mm |
| December | -10.3 °C | 1.5 °C | 11.68 mm |
| Annual | -0.9 °C | 14.9 °C | 305.54 mm |
| 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 : -31.7°C to -28.9°C |
| Plant Hardiness Zone - 2012 | Zone 4b : -31.7°C to -28.9°C |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | BSk - Cold Semi-Arid Climate |