Sumiton, Alabama has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 10.2 °C (low) to 23.3 °C (high). Annual precipitation averages 1489 Millimeters. Sumiton is located in USDA Plant Hardiness Zone 8a. 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 | -0.2 °C | 12.2 °C | 145.29 mm |
| February | 1.4 °C | 14.6 °C | 134.37 mm |
| March | 5.3 °C | 19.2 °C | 154.18 mm |
| April | 9.2 °C | 23.8 °C | 131.32 mm |
| May | 14.4 °C | 27.6 °C | 119.89 mm |
| June | 18.8 °C | 31 °C | 121.16 mm |
| July | 20.6 °C | 32.7 °C | 128.52 mm |
| August | 20.2 °C | 32.4 °C | 97.03 mm |
| September | 16.9 °C | 29.9 °C | 118.62 mm |
| October | 10.1 °C | 24.4 °C | 87.12 mm |
| November | 4.3 °C | 18.2 °C | 117.35 mm |
| December | 1.6 °C | 13.5 °C | 134.11 mm |
| Annual | 10.2 °C | 23.3 °C | 1488.96 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 8a : -12.2°C to -9.4°C |
| Plant Hardiness Zone - 2012 | Zone 7b : -15°C to -12.2°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |