Mershon, Georgia has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 55.2 °F (low) to 78.3 °F (high). Annual precipitation averages 48.8 Inches. Mershon 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 | 38.1 °F | 62.1 °F | 4.13 in. |
| February | 40.8 °F | 65.6 °F | 3.69 in. |
| March | 46.5 °F | 72.2 °F | 4.01 in. |
| April | 53.4 °F | 78.8 °F | 3.23 in. |
| May | 61.4 °F | 85.6 °F | 3.06 in. |
| June | 69.0 °F | 89.9 °F | 5.98 in. |
| July | 71.7 °F | 92.3 °F | 5.37 in. |
| August | 71.5 °F | 91.1 °F | 6.22 in. |
| September | 67.0 °F | 86.9 °F | 4.23 in. |
| October | 56.5 °F | 79.5 °F | 3.46 in. |
| November | 45.8 °F | 71.2 °F | 2.24 in. |
| December | 40.7 °F | 64.4 °F | 3.22 in. |
| Annual | 55.2 °F | 78.3 °F | 48.84 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 | Severe Drought |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |