Somerville, Texas has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 56.7 °F (low) to 80 °F (high). Annual precipitation averages 42.3 Inches. Somerville is located in USDA Plant Hardiness Zone 8b. The growing season typically runs from the last frost around Mar. 1 - Mar. 10 through the first frost around Nov. 11 - Nov. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 38.8 °F | 61.7 °F | 3.28 in. |
| February | 42.5 °F | 65.3 °F | 2.86 in. |
| March | 49.2 °F | 72.1 °F | 3.26 in. |
| April | 56.3 °F | 79.5 °F | 3.33 in. |
| May | 64.4 °F | 86.3 °F | 4.89 in. |
| June | 71.1 °F | 92.9 °F | 3.95 in. |
| July | 73.1 °F | 95.8 °F | 1.93 in. |
| August | 72.7 °F | 97.2 °F | 3.29 in. |
| September | 67.2 °F | 91.7 °F | 3.42 in. |
| October | 57.0 °F | 82.8 °F | 4.7 in. |
| November | 47.6 °F | 71.6 °F | 3.74 in. |
| December | 40.4 °F | 63.6 °F | 3.6 in. |
| Annual | 56.7 °F | 80 °F | 42.25 in. |
| Average First Frost Date | Nov. 11 - Nov. 20 |
| Average Last Frost Date | Mar. 1 - Mar. 10 |
| Average Days With Frost | 30-40 Days |
| Plant Hardiness Zone | Zone 8b : 15°F to 20°F |
| Plant Hardiness Zone - 2012 | Zone 8b : 15°F to 20°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |