Williston, South Carolina has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 52.3 °F (low) to 75.7 °F (high). Annual precipitation averages 48.1 Inches. Williston is located in USDA Plant Hardiness Zone 8b. 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 | 34.6 °F | 57.6 °F | 3.97 in. |
| February | 37.3 °F | 61.4 °F | 3.73 in. |
| March | 43.0 °F | 68.8 °F | 3.99 in. |
| April | 50.9 °F | 76.4 °F | 3.25 in. |
| May | 59.8 °F | 83.7 °F | 3.33 in. |
| June | 67.2 °F | 89.2 °F | 5.68 in. |
| July | 70.4 °F | 92.1 °F | 4.91 in. |
| August | 69.4 °F | 89.8 °F | 5.13 in. |
| September | 64.0 °F | 85.5 °F | 4.03 in. |
| October | 52.7 °F | 76.9 °F | 3.3 in. |
| November | 41.9 °F | 67.1 °F | 2.89 in. |
| December | 36.4 °F | 59.5 °F | 3.88 in. |
| Annual | 52.3 °F | 75.7 °F | 48.09 in. |
| Average First Frost Date | Nov. 1 - Nov. 10 |
| Average Last Frost Date | Mar. 21 - Mar. 31 |
| Average Days With Frost | 40-50 Days |
| Plant Hardiness Zone | Zone 8b : 15°F to 20°F |
| Plant Hardiness Zone - 2012 | Zone 8a : 10°F to 15°F |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |