Douglas, Wyoming has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 0.3 °C (low) to 16.1 °C (high). Annual precipitation averages 346.2 Millimeters. Douglas is located in USDA Plant Hardiness Zone 4b. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Sep. 21 - Sep. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -10.2 °C | 3.8 °C | 10.16 mm |
| February | -9.4 °C | 4.7 °C | 15.75 mm |
| March | -4.8 °C | 10.2 °C | 25.15 mm |
| April | -1 °C | 14.1 °C | 44.96 mm |
| May | 4.2 °C | 19.4 °C | 65.28 mm |
| June | 9.3 °C | 26.1 °C | 45.47 mm |
| July | 13.2 °C | 31.2 °C | 33.53 mm |
| August | 11.9 °C | 30.2 °C | 21.08 mm |
| September | 6.3 °C | 24.7 °C | 25.15 mm |
| October | -0.4 °C | 16.3 °C | 33.78 mm |
| November | -5.9 °C | 9.2 °C | 14.99 mm |
| December | -10.2 °C | 3.7 °C | 10.92 mm |
| Annual | 0.3 °C | 16.1 °C | 346.22 mm |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | Over 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 | Extreme Drought |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |