Hannahs Mill, Georgia has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 51.9 °F (low) to 74.7 °F (high). Annual precipitation averages 50.9 Inches. Hannahs Mill 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 | 34.3 °F | 56.5 °F | 4.6 in. |
| February | 37.0 °F | 60.3 °F | 4.53 in. |
| March | 43.0 °F | 68.0 °F | 5.26 in. |
| April | 50.0 °F | 75.3 °F | 3.98 in. |
| May | 58.9 °F | 82.5 °F | 3.3 in. |
| June | 66.5 °F | 87.8 °F | 4.13 in. |
| July | 69.7 °F | 90.4 °F | 5.26 in. |
| August | 69.2 °F | 89.5 °F | 4.37 in. |
| September | 63.4 °F | 85.0 °F | 3.68 in. |
| October | 52.4 °F | 76.2 °F | 3.11 in. |
| November | 42.0 °F | 66.5 °F | 3.82 in. |
| December | 36.8 °F | 58.6 °F | 4.89 in. |
| Annual | 51.9 °F | 74.7 °F | 50.93 in. |
| Average First Frost Date | Nov. 1 - Nov. 10 |
| Average Last Frost Date | Mar. 21 - Mar. 31 |
| Average Days With Frost | 40-50 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 |