Newnan, Georgia has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 10.3 °C (low) to 22.6 °C (high). Annual precipitation averages 1372.1 Millimeters. Newnan is located in USDA Plant Hardiness Zone 8a. The growing season typically runs from the last frost around Mar. 11 - Mar. 20 through the first frost around Nov. 11 - Nov. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 0.1 °C | 12.2 °C | 128.52 mm |
| February | 1.8 °C | 14.4 °C | 130.05 mm |
| March | 5.2 °C | 18.8 °C | 132.33 mm |
| April | 9.2 °C | 22.9 °C | 112.01 mm |
| May | 14.4 °C | 26.8 °C | 92.46 mm |
| June | 18.6 °C | 29.9 °C | 108.46 mm |
| July | 20.4 °C | 31.6 °C | 133.86 mm |
| August | 20.2 °C | 31 °C | 114.81 mm |
| September | 16.8 °C | 28.3 °C | 100.84 mm |
| October | 10.6 °C | 23.3 °C | 84.33 mm |
| November | 4.5 °C | 17.9 °C | 105.16 mm |
| December | 1.6 °C | 13.5 °C | 129.29 mm |
| Annual | 10.3 °C | 22.6 °C | 1372.12 mm |
| Average First Frost Date | Nov. 11 - Nov. 20 |
| Average Last Frost Date | Mar. 11 - Mar. 20 |
| Average Days With Frost | 40-50 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 | Abnormally Dry |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |