Williamston, South Carolina has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 50.3 °F (low) to 72.8 °F (high). Annual precipitation averages 49.3 Inches. Williamston 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 Nov. 1 - Nov. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 31.9 °F | 53.1 °F | 4.48 in. |
| February | 34.3 °F | 57.0 °F | 4.11 in. |
| March | 40.7 °F | 64.5 °F | 4.64 in. |
| April | 48.6 °F | 73.6 °F | 3.85 in. |
| May | 57.5 °F | 80.6 °F | 3.57 in. |
| June | 65.7 °F | 87.3 °F | 4.43 in. |
| July | 69.1 °F | 91.1 °F | 3.92 in. |
| August | 68.3 °F | 89.3 °F | 4.63 in. |
| September | 62.5 °F | 83.6 °F | 3.43 in. |
| October | 50.6 °F | 74.2 °F | 3.36 in. |
| November | 40.1 °F | 63.4 °F | 3.9 in. |
| December | 34.7 °F | 55.3 °F | 4.94 in. |
| Annual | 50.3 °F | 72.8 °F | 49.26 in. |
| Average First Frost Date | Nov. 1 - Nov. 10 |
| 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 8a : 10°F to 15°F |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |