Orwell, Ohio has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 4 °C (low) to 15 °C (high). Annual precipitation averages 1133.9 Millimeters. Orwell 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 | -7.8 °C | 0.9 °C | 83.31 mm |
| February | -7.7 °C | 2.3 °C | 59.94 mm |
| March | -3.4 °C | 7.3 °C | 81.03 mm |
| April | 2.3 °C | 14.8 °C | 101.35 mm |
| May | 8.3 °C | 21.1 °C | 101.85 mm |
| June | 13.4 °C | 25.6 °C | 114.3 mm |
| July | 15.7 °C | 27.8 °C | 116.33 mm |
| August | 14.7 °C | 26.9 °C | 95.5 mm |
| September | 11.2 °C | 23.4 °C | 106.93 mm |
| October | 5.3 °C | 16.7 °C | 99.06 mm |
| November | 0.4 °C | 9.8 °C | 86.87 mm |
| December | -4.1 °C | 3.8 °C | 87.38 mm |
| Annual | 4 °C | 15 °C | 1133.85 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 |