Cumming, Georgia has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 9.5 °C (low) to 21.5 °C (high). Annual precipitation averages 1461.8 Millimeters. Cumming 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. 11 - Nov. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -0.7 °C | 10.4 °C | 136.65 mm |
| February | 0.8 °C | 12.7 °C | 131.06 mm |
| March | 4.2 °C | 17.2 °C | 136.91 mm |
| April | 8.4 °C | 21.9 °C | 117.09 mm |
| May | 13.4 °C | 25.8 °C | 105.16 mm |
| June | 17.9 °C | 29.3 °C | 119.89 mm |
| July | 19.9 °C | 30.9 °C | 136.4 mm |
| August | 19.5 °C | 30.7 °C | 126.75 mm |
| September | 16.1 °C | 27.8 °C | 108.46 mm |
| October | 9.7 °C | 22.4 °C | 100.84 mm |
| November | 3.8 °C | 16.7 °C | 113.79 mm |
| December | 1 °C | 11.9 °C | 128.78 mm |
| Annual | 9.5 °C | 21.5 °C | 1461.78 mm |
| Average First Frost Date | Nov. 11 - Nov. 20 |
| Average Last Frost Date | Mar. 21 - Mar. 31 |
| 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 |