Clarktown, Ohio has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 6.2 °C (low) to 18.6 °C (high). Annual precipitation averages 1104.9 Millimeters. Clarktown is located in USDA Plant Hardiness Zone 6b. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -5.1 °C | 4.9 °C | 83.57 mm |
| February | -3.9 °C | 7.2 °C | 78.99 mm |
| March | -0.2 °C | 12.4 °C | 103.12 mm |
| April | 5.2 °C | 19.5 °C | 101.85 mm |
| May | 10.9 °C | 24.1 °C | 115.82 mm |
| June | 15.7 °C | 28.3 °C | 106.93 mm |
| July | 17.8 °C | 30.1 °C | 114.3 mm |
| August | 16.8 °C | 29.7 °C | 83.06 mm |
| September | 12.8 °C | 26.6 °C | 83.06 mm |
| October | 6.3 °C | 20.2 °C | 76.2 mm |
| November | 0.7 °C | 12.9 °C | 71.37 mm |
| December | -2.5 °C | 7.1 °C | 86.61 mm |
| Annual | 6.2 °C | 18.6 °C | 1104.88 mm |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 100-125 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 | Cfa - Humid Subtropical Climate |