Viola, Tennessee has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 8.6 °C (low) to 20.7 °C (high). Annual precipitation averages 1437.1 Millimeters. Viola is located in USDA Plant Hardiness Zone 7b. The growing season typically runs from the last frost around Apr. 1 - Apr. 10 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -1.9 °C | 8.8 °C | 124.46 mm |
| February | -0.4 °C | 11.2 °C | 125.73 mm |
| March | 3.2 °C | 15.9 °C | 135.38 mm |
| April | 7.8 °C | 21.2 °C | 132.59 mm |
| May | 13 °C | 25.3 °C | 119.89 mm |
| June | 17.4 °C | 28.9 °C | 131.32 mm |
| July | 19.5 °C | 30.6 °C | 121.41 mm |
| August | 18.7 °C | 30.3 °C | 106.17 mm |
| September | 15 °C | 27.6 °C | 102.36 mm |
| October | 8.3 °C | 21.9 °C | 79.76 mm |
| November | 2.5 °C | 15.7 °C | 104.14 mm |
| December | -0.2 °C | 10.7 °C | 153.92 mm |
| Annual | 8.6 °C | 20.7 °C | 1437.13 mm |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 1 - Apr. 10 |
| Average Days With Frost | 50-75 Days |
| Plant Hardiness Zone | Zone 7b : -15°C to -12.2°C |
| Plant Hardiness Zone - 2012 | Zone 7a : -17.8°C to -15°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |