Muddy, Montana has a Cold Semi-Arid Climate climate (Köppen classification: BSk). Average annual temperatures range from -0.5 °C (low) to 16 °C (high). Annual precipitation averages 404.6 Millimeters. Muddy is located in USDA Plant Hardiness Zone 4a. 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 | -12.3 °C | 1.9 °C | 14.22 mm |
| February | -10.5 °C | 3.7 °C | 15.49 mm |
| March | -5.6 °C | 9.7 °C | 24.89 mm |
| April | -1.1 °C | 14.8 °C | 42.67 mm |
| May | 4.1 °C | 19.9 °C | 77.72 mm |
| June | 8.9 °C | 25.9 °C | 62.48 mm |
| July | 12.3 °C | 31.4 °C | 37.85 mm |
| August | 10.9 °C | 31.2 °C | 22.35 mm |
| September | 5.8 °C | 25.4 °C | 36.32 mm |
| October | -0.6 °C | 16.7 °C | 37.85 mm |
| November | -6.3 °C | 8.4 °C | 18.8 mm |
| December | -11.4 °C | 2.7 °C | 13.97 mm |
| Annual | -0.5 °C | 16 °C | 404.61 mm |
| 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 4a : -34.4°C to -31.7°C |
| Plant Hardiness Zone - 2012 | Zone 4a : -34.4°C to -31.7°C |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | BSk - Cold Semi-Arid Climate |