Washington, Georgia has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 10.7 °C (low) to 23.3 °C (high). Annual precipitation averages 1149.9 Millimeters. Washington 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 | 0.9 °C | 12.9 °C | 103.38 mm |
| February | 2.1 °C | 14.9 °C | 102.87 mm |
| March | 5.3 °C | 19.2 °C | 112.78 mm |
| April | 9.7 °C | 23.6 °C | 81.53 mm |
| May | 14.7 °C | 27.5 °C | 76.96 mm |
| June | 19.2 °C | 31.1 °C | 101.85 mm |
| July | 21.2 °C | 32.7 °C | 104.65 mm |
| August | 20.7 °C | 31.9 °C | 105.92 mm |
| September | 17.4 °C | 29.3 °C | 96.77 mm |
| October | 10.8 °C | 24.2 °C | 71.63 mm |
| November | 4.7 °C | 18.6 °C | 85.09 mm |
| December | 2.1 °C | 14.1 °C | 106.43 mm |
| Annual | 10.7 °C | 23.3 °C | 1149.86 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 8b : -9.4°C to -6.7°C |
| Plant Hardiness Zone - 2012 | Zone 8a : -12.2°C to -9.4°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |