Glennville, Georgia has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 55.1 °F (low) to 78.1 °F (high). Annual precipitation averages 48.6 Inches. Glennville is located in USDA Plant Hardiness Zone 9a. The growing season typically runs from the last frost around Mar. 1 - Mar. 10 through the first frost around Nov. 21 - Nov. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 37.7 °F | 61.6 °F | 4.02 in. |
| February | 40.4 °F | 64.9 °F | 3.76 in. |
| March | 46.3 °F | 71.6 °F | 4.02 in. |
| April | 53.0 °F | 78.9 °F | 3.19 in. |
| May | 61.7 °F | 85.6 °F | 3.38 in. |
| June | 69.1 °F | 90.4 °F | 5.3 in. |
| July | 71.8 °F | 92.5 °F | 5.26 in. |
| August | 71.6 °F | 91.2 °F | 6.43 in. |
| September | 66.9 °F | 87.1 °F | 3.69 in. |
| October | 56.3 °F | 79.3 °F | 3.26 in. |
| November | 45.7 °F | 70.5 °F | 2.39 in. |
| December | 40.3 °F | 63.6 °F | 3.88 in. |
| Annual | 55.1 °F | 78.1 °F | 48.58 in. |
| Average First Frost Date | Nov. 21 - Nov. 30 |
| Average Last Frost Date | Mar. 1 - Mar. 10 |
| Average Days With Frost | 20-30 Days |
| Plant Hardiness Zone | Zone 9a : 20°F to 25°F |
| Plant Hardiness Zone - 2012 | Zone 8b : 15°F to 20°F |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |