Ashburn, Georgia has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 13.1 °C (low) to 24.7 °C (high). Annual precipitation averages 1253.5 Millimeters. Ashburn 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. 11 - Nov. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 3.7 °C | 15.1 °C | 115.57 mm |
| February | 5.2 °C | 17.2 °C | 111 mm |
| March | 8.2 °C | 21.2 °C | 123.44 mm |
| April | 12.6 °C | 25 °C | 86.87 mm |
| May | 17.2 °C | 29.1 °C | 80.01 mm |
| June | 20.8 °C | 31.5 °C | 130.81 mm |
| July | 22.2 °C | 32.7 °C | 119.38 mm |
| August | 21.8 °C | 32.2 °C | 115.06 mm |
| September | 19.1 °C | 30.1 °C | 107.19 mm |
| October | 13.5 °C | 25.7 °C | 82.55 mm |
| November | 7.9 °C | 20.4 °C | 79.76 mm |
| December | 5.1 °C | 16.4 °C | 101.85 mm |
| Annual | 13.1 °C | 24.7 °C | 1253.49 mm |
| Average First Frost Date | Nov. 11 - Nov. 20 |
| Average Last Frost Date | Mar. 1 - Mar. 10 |
| Average Days With Frost | 20-30 Days |
| Plant Hardiness Zone | Zone 9a : -6.7°C to -3.9°C |
| Plant Hardiness Zone - 2012 | Zone 8b : -9.4°C to -6.7°C |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |