Douglas, Michigan has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 5 °C (low) to 13.4 °C (high). Annual precipitation averages 945.4 Millimeters. Douglas is located in USDA Plant Hardiness Zone 6b. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -6.6 °C | -0.2 °C | 70.1 mm |
| February | -6.2 °C | 1 °C | 52.32 mm |
| March | -2.7 °C | 5.7 °C | 53.09 mm |
| April | 2.8 °C | 12.9 °C | 89.92 mm |
| May | 8.9 °C | 18.4 °C | 100.84 mm |
| June | 13.9 °C | 23.7 °C | 91.69 mm |
| July | 16.9 °C | 25.8 °C | 81.79 mm |
| August | 16.4 °C | 25.2 °C | 90.17 mm |
| September | 12.4 °C | 22.1 °C | 80.77 mm |
| October | 6.6 °C | 15.3 °C | 95.5 mm |
| November | 1.3 °C | 8.4 °C | 74.93 mm |
| December | -3.2 °C | 2.7 °C | 64.26 mm |
| Annual | 5 °C | 13.4 °C | 945.38 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 6b : -20.6°C to -17.8°C |
| Plant Hardiness Zone - 2012 | Zone 6b : -20.6°C to -17.8°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |