Ryegate, Montana has a Cold Semi-Arid Climate climate (Köppen classification: BSk). Annual precipitation averages 370.6 Millimeters. Ryegate 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 | -9.9 °C | 3.4 °C | 9.65 mm |
| February | -9.3 °C | 4.9 °C | 11.18 mm |
| March | -5.2 °C | 9.8 °C | 18.54 mm |
| April | -1.1 °C | 14.5 °C | 40.39 mm |
| May | 4 °C | 19.5 °C | 63.5 mm |
| June | 8.8 °C | 24.2 °C | 73.41 mm |
| July | 11.9 °C | 29.7 °C | 39.88 mm |
| August | 10.6 °C | 29.3 °C | 29.46 mm |
| September | 5.8 °C | 23.5 °C | 28.19 mm |
| October | -0.1 °C | 16.1 °C | 29.46 mm |
| November | -5.7 °C | 8.3 °C | 14.48 mm |
| December | -9.7 °C | 3.2 °C | 12.45 mm |
| Annual | 0 °C | 15.5 °C | 370.59 mm |
| Average First Frost Date | Sep.11 - Sep. 20 |
| Average Last Frost Date | May 11 - May 20 |
| Average Days With Frost | Over 180 Days |
| Plant Hardiness Zone | Zone 4b : -31.7°C to -28.9°C |
| Plant Hardiness Zone - 2012 | Zone 4a : -34.4°C to -31.7°C |
| Current Drought Conditions | Extreme Drought |
| Köppen Climate Classification | BSk - Cold Semi-Arid Climate |