Grantville, Georgia has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 50.3 °F (low) to 73.2 °F (high). Annual precipitation averages 52.9 Inches. Grantville 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 | 32.3 °F | 54.6 °F | 4.94 in. |
| February | 35.2 °F | 58.6 °F | 5.01 in. |
| March | 41.3 °F | 66.3 °F | 5.16 in. |
| April | 48.3 °F | 73.8 °F | 4.36 in. |
| May | 57.5 °F | 80.8 °F | 3.6 in. |
| June | 65.1 °F | 86.4 °F | 4.32 in. |
| July | 68.4 °F | 89.5 °F | 4.98 in. |
| August | 67.9 °F | 88.4 °F | 4.28 in. |
| September | 62.0 °F | 83.6 °F | 3.75 in. |
| October | 50.6 °F | 74.5 °F | 3.34 in. |
| November | 39.9 °F | 64.8 °F | 4.08 in. |
| December | 35.0 °F | 56.9 °F | 5.12 in. |
| Annual | 50.3 °F | 73.2 °F | 52.94 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 8a : 10°F to 15°F |
| Plant Hardiness Zone - 2012 | Zone 8a : 10°F to 15°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |