Simpsonville, South Carolina has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 50.1 °F (low) to 71.9 °F (high). Annual precipitation averages 51 Inches. Simpsonville 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. 11 - Nov. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 31.6 °F | 52.5 °F | 4.36 in. |
| February | 34.0 °F | 56.5 °F | 4.05 in. |
| March | 40.5 °F | 63.8 °F | 4.74 in. |
| April | 48.4 °F | 72.6 °F | 4.11 in. |
| May | 57.5 °F | 79.6 °F | 3.75 in. |
| June | 65.5 °F | 86.3 °F | 4.45 in. |
| July | 69.1 °F | 89.9 °F | 4.2 in. |
| August | 68.2 °F | 88.1 °F | 4.99 in. |
| September | 62.3 °F | 82.5 °F | 3.65 in. |
| October | 50.2 °F | 73.0 °F | 3.68 in. |
| November | 39.5 °F | 62.9 °F | 3.99 in. |
| December | 34.3 °F | 54.8 °F | 4.98 in. |
| Annual | 50.1 °F | 71.9 °F | 50.95 in. |
| Average First Frost Date | Nov. 11 - Nov. 20 |
| 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 | Severe Drought |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |