Thomson, Georgia has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 11 °C (low) to 23.6 °C (high). Annual precipitation averages 1188.5 Millimeters. Thomson is located in USDA Plant Hardiness Zone 8b. The growing season typically runs from the last frost around Mar. 21 - Mar. 31 through the first frost around Nov. 1 - Nov. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 1.2 °C | 13.4 °C | 108.46 mm |
| February | 2.3 °C | 15.2 °C | 101.09 mm |
| March | 5.6 °C | 19.5 °C | 119.13 mm |
| April | 10.1 °C | 23.9 °C | 80.52 mm |
| May | 15 °C | 27.8 °C | 79.5 mm |
| June | 19.4 °C | 31.2 °C | 115.06 mm |
| July | 21.3 °C | 32.9 °C | 104.65 mm |
| August | 20.7 °C | 32.3 °C | 114.3 mm |
| September | 17.6 °C | 29.3 °C | 102.11 mm |
| October | 11.1 °C | 24.4 °C | 74.93 mm |
| November | 5 °C | 18.9 °C | 82.55 mm |
| December | 2.5 °C | 14.6 °C | 106.17 mm |
| Annual | 11 °C | 23.6 °C | 1188.47 mm |
| Average First Frost Date | Nov. 1 - Nov. 10 |
| Average Last Frost Date | Mar. 21 - Mar. 31 |
| 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 | Abnormally Dry |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |