Clarksville, Indiana has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 8.9 °C (low) to 19.9 °C (high). Annual precipitation averages 1248.2 Millimeters. Clarksville is located in USDA Plant Hardiness Zone 7a. The growing season typically runs from the last frost around Apr. 1 - Apr. 10 through the first frost around Nov. 1 - Nov. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -3.1 °C | 6.1 °C | 91.19 mm |
| February | -1.6 °C | 8.7 °C | 91.44 mm |
| March | 2.7 °C | 14.1 °C | 115.82 mm |
| April | 8.4 °C | 20.7 °C | 124.71 mm |
| May | 14.1 °C | 25.4 °C | 129.03 mm |
| June | 18.6 °C | 29.7 °C | 117.35 mm |
| July | 20.6 °C | 31.4 °C | 103.63 mm |
| August | 19.9 °C | 31.1 °C | 85.6 mm |
| September | 15.8 °C | 27.9 °C | 96.52 mm |
| October | 9.2 °C | 21.6 °C | 91.69 mm |
| November | 3.4 °C | 14.2 °C | 91.44 mm |
| December | -0.7 °C | 8.2 °C | 109.73 mm |
| Annual | 8.9 °C | 19.9 °C | 1248.15 mm |
| Average First Frost Date | Nov. 1 - Nov. 10 |
| Average Last Frost Date | Apr. 1 - Apr. 10 |
| Average Days With Frost | 75-100 Days |
| Plant Hardiness Zone | Zone 7a : -17.8°C to -15°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 |