Rock Hill, South Carolina has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 10.2 °C (low) to 22.3 °C (high). Annual precipitation averages 1122.2 Millimeters. Rock Hill 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 | -0.4 °C | 11.3 °C | 96.01 mm |
| February | 1.1 °C | 13.4 °C | 81.53 mm |
| March | 4.8 °C | 17.7 °C | 102.11 mm |
| April | 9.6 °C | 22.8 °C | 92.96 mm |
| May | 14.6 °C | 26.7 °C | 89.66 mm |
| June | 19.1 °C | 30.4 °C | 104.65 mm |
| July | 21 °C | 32.3 °C | 97.03 mm |
| August | 20.3 °C | 31.3 °C | 104.65 mm |
| September | 17.1 °C | 28.4 °C | 95.5 mm |
| October | 10.3 °C | 22.9 °C | 78.49 mm |
| November | 4.2 °C | 17.2 °C | 84.07 mm |
| December | 1.1 °C | 12.7 °C | 95.5 mm |
| Annual | 10.2 °C | 22.3 °C | 1122.16 mm |
| 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 : -12.2°C to -9.4°C |
| Plant Hardiness Zone - 2012 | Zone 8a : -12.2°C to -9.4°C |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |