Windham, Ohio has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 3.9 °C (low) to 15.6 °C (high). Annual precipitation averages 1042.2 Millimeters. Windham is located in USDA Plant Hardiness Zone 6a. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -7.9 °C | 1.3 °C | 72.64 mm |
| February | -7.4 °C | 2.9 °C | 57.91 mm |
| March | -3 °C | 8.1 °C | 78.99 mm |
| April | 2.5 °C | 15.7 °C | 97.28 mm |
| May | 8.2 °C | 21.6 °C | 103.63 mm |
| June | 13.3 °C | 26.2 °C | 104.9 mm |
| July | 15.4 °C | 28.3 °C | 112.27 mm |
| August | 14.4 °C | 27.5 °C | 87.12 mm |
| September | 10.8 °C | 24.1 °C | 95.5 mm |
| October | 4.6 °C | 17.1 °C | 83.57 mm |
| November | -0.1 °C | 10 °C | 74.93 mm |
| December | -4.3 °C | 3.9 °C | 73.41 mm |
| Annual | 3.9 °C | 15.6 °C | 1042.15 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 6a : -23.3°C to -20.6°C |
| Plant Hardiness Zone - 2012 | Zone 6a : -23.3°C to -20.6°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |