Stonewall Gap, Colorado has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from -1.3 °C (low) to 15.5 °C (high). Annual precipitation averages 501.7 Millimeters. Stonewall Gap is located in USDA Plant Hardiness Zone 6a. 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 | -11 °C | 4.6 °C | 19.05 mm |
| February | -9.2 °C | 6.3 °C | 24.89 mm |
| March | -5.7 °C | 9.9 °C | 46.74 mm |
| April | -2.6 °C | 14.2 °C | 45.47 mm |
| May | 1.8 °C | 19.2 °C | 46.23 mm |
| June | 6.1 °C | 24.9 °C | 31.24 mm |
| July | 9.1 °C | 26.6 °C | 85.09 mm |
| August | 8.6 °C | 25.7 °C | 80.52 mm |
| September | 4.7 °C | 22.6 °C | 42.67 mm |
| October | -0.9 °C | 17.1 °C | 34.54 mm |
| November | -6.5 °C | 10.2 °C | 23.88 mm |
| December | -10.5 °C | 4.7 °C | 21.34 mm |
| Annual | -1.3 °C | 15.5 °C | 501.66 mm |
| 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 6a : -23.3°C to -20.6°C |
| Plant Hardiness Zone - 2012 | Zone 5b : -26.1°C to -23.3°C |
| Current Drought Conditions | Exceptional Drought |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |