Unionville, Tennessee has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 47 °F (low) to 70.1 °F (high). Annual precipitation averages 55.8 Inches. Unionville 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 | 27.6 °F | 47.8 °F | 4.71 in. |
| February | 30.5 °F | 52.3 °F | 5.01 in. |
| March | 36.8 °F | 61.1 °F | 5.52 in. |
| April | 45.4 °F | 70.7 °F | 5.05 in. |
| May | 55.4 °F | 78.4 °F | 4.77 in. |
| June | 63.3 °F | 85.7 °F | 4.83 in. |
| July | 67.4 °F | 88.6 °F | 4.68 in. |
| August | 65.7 °F | 88.7 °F | 3.76 in. |
| September | 58.6 °F | 83.4 °F | 4.27 in. |
| October | 46.4 °F | 72.7 °F | 3.45 in. |
| November | 36.1 °F | 60.5 °F | 3.92 in. |
| December | 30.8 °F | 50.9 °F | 5.81 in. |
| Annual | 47 °F | 70.1 °F | 55.78 in. |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 1 - Apr. 10 |
| Average Days With Frost | 75-100 Days |
| Plant Hardiness Zone | Zone 7b : 5°F to 10°F |
| Plant Hardiness Zone - 2012 | Zone 7a : 0°F to 5°F |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |