Gun Barrel City, Texas has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 12.3 °C (low) to 24.8 °C (high). Annual precipitation averages 1096.8 Millimeters. Gun Barrel City is located in USDA Plant Hardiness Zone 8b. 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 | 1.2 °C | 13.7 °C | 83.06 mm |
| February | 3.3 °C | 15.9 °C | 86.87 mm |
| March | 7.4 °C | 19.6 °C | 101.6 mm |
| April | 11.5 °C | 24.2 °C | 95.5 mm |
| May | 16.8 °C | 28.2 °C | 117.86 mm |
| June | 21.4 °C | 32.6 °C | 101.6 mm |
| July | 22.9 °C | 34.9 °C | 53.59 mm |
| August | 22.4 °C | 35.4 °C | 63.25 mm |
| September | 18.9 °C | 31.9 °C | 79.76 mm |
| October | 12.4 °C | 26.2 °C | 128.27 mm |
| November | 6.7 °C | 19.7 °C | 86.11 mm |
| December | 2.3 °C | 14.7 °C | 99.31 mm |
| Annual | 12.3 °C | 24.8 °C | 1096.78 mm |
| Average First Frost Date | Nov. 11 - Nov. 20 |
| Average Last Frost Date | Mar. 1 - Mar. 10 |
| Average Days With Frost | 30-40 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 |