Swansea, South Carolina has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 52.9 °F (low) to 75.3 °F (high). Annual precipitation averages 48.4 Inches. Swansea 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 | 34.7 °F | 57.0 °F | 4.06 in. |
| February | 36.9 °F | 60.5 °F | 3.74 in. |
| March | 43.5 °F | 67.8 °F | 4.19 in. |
| April | 51.4 °F | 76.0 °F | 3.22 in. |
| May | 60.2 °F | 83.2 °F | 3.4 in. |
| June | 68.3 °F | 89.2 °F | 5.12 in. |
| July | 71.4 °F | 92.0 °F | 4.76 in. |
| August | 70.6 °F | 90.3 °F | 5.02 in. |
| September | 64.9 °F | 85.3 °F | 4.27 in. |
| October | 53.3 °F | 76.2 °F | 3.44 in. |
| November | 42.2 °F | 66.4 °F | 3.16 in. |
| December | 36.8 °F | 59.3 °F | 3.98 in. |
| Annual | 52.9 °F | 75.3 °F | 48.36 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 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 |