Joanna, South Carolina has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 10 °C (low) to 22.9 °C (high). Annual precipitation averages 1175.3 Millimeters. Joanna is located in USDA Plant Hardiness Zone 8a. The growing season typically runs from the last frost around Apr. 1 - Apr. 10 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -0.2 °C | 12.2 °C | 105.16 mm |
| February | 1.1 °C | 14.3 °C | 95.5 mm |
| March | 4.4 °C | 18.6 °C | 109.98 mm |
| April | 9 °C | 23.5 °C | 85.09 mm |
| May | 14.2 °C | 27.3 °C | 84.58 mm |
| June | 18.8 °C | 31.1 °C | 110.24 mm |
| July | 20.7 °C | 32.8 °C | 99.31 mm |
| August | 20.2 °C | 31.8 °C | 102.87 mm |
| September | 16.7 °C | 28.8 °C | 95.76 mm |
| October | 9.9 °C | 23.4 °C | 85.09 mm |
| November | 3.9 °C | 17.8 °C | 91.69 mm |
| December | 1.1 °C | 13.4 °C | 109.98 mm |
| Annual | 10 °C | 22.9 °C | 1175.25 mm |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 1 - Apr. 10 |
| Average Days With Frost | 50-75 Days |
| Plant Hardiness Zone | Zone 8a : -12.2°C to -9.4°C |
| Plant Hardiness Zone - 2012 | Zone 7b : -15°C to -12.2°C |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |