Somerville, Tennessee has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 50.2 °F (low) to 71.6 °F (high). Annual precipitation averages 55.8 Inches. Somerville is located in USDA Plant Hardiness Zone 8a. The growing season typically runs from the last frost around Mar. 21 - Mar. 31 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 30.3 °F | 49.1 °F | 4.3 in. |
| February | 33.3 °F | 53.9 °F | 4.8 in. |
| March | 40.6 °F | 62.7 °F | 5.66 in. |
| April | 49.2 °F | 72.4 °F | 5.73 in. |
| May | 59.1 °F | 80.0 °F | 5.15 in. |
| June | 67.1 °F | 87.3 °F | 4.49 in. |
| July | 70.3 °F | 90.2 °F | 4.43 in. |
| August | 68.5 °F | 90.0 °F | 3.14 in. |
| September | 61.3 °F | 84.5 °F | 4.22 in. |
| October | 49.6 °F | 74.3 °F | 4.2 in. |
| November | 39.5 °F | 62.1 °F | 4.28 in. |
| December | 33.1 °F | 52.1 °F | 5.42 in. |
| Annual | 50.2 °F | 71.6 °F | 55.82 in. |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Mar. 21 - Mar. 31 |
| Average Days With Frost | 50-75 Days |
| Plant Hardiness Zone | Zone 8a : 10°F to 15°F |
| Plant Hardiness Zone - 2012 | Zone 7b : 5°F to 10°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |