Bethlehem, Georgia has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 10.5 °C (low) to 22.4 °C (high). Annual precipitation averages 1335.3 Millimeters. Bethlehem is located in USDA Plant Hardiness Zone 8b. 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 | 0.6 °C | 11.8 °C | 125.22 mm |
| February | 1.9 °C | 13.8 °C | 116.84 mm |
| March | 5.3 °C | 18.3 °C | 122.43 mm |
| April | 9.6 °C | 22.8 °C | 104.14 mm |
| May | 14.4 °C | 26.7 °C | 93.73 mm |
| June | 18.8 °C | 30.3 °C | 123.44 mm |
| July | 20.7 °C | 32 °C | 118.87 mm |
| August | 20.3 °C | 31.2 °C | 113.28 mm |
| September | 17.1 °C | 28.3 °C | 107.44 mm |
| October | 10.8 °C | 23.2 °C | 96.27 mm |
| November | 4.8 °C | 17.7 °C | 100.84 mm |
| December | 1.9 °C | 13.1 °C | 112.78 mm |
| Annual | 10.5 °C | 22.4 °C | 1335.28 mm |
| Average First Frost Date | Nov. 11 - Nov. 20 |
| Average Last Frost Date | Mar. 11 - Mar. 20 |
| Average Days With Frost | 50-75 Days |
| Plant Hardiness Zone | Zone 8b : -9.4°C to -6.7°C |
| Plant Hardiness Zone - 2012 | Zone 8a : -12.2°C to -9.4°C |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |