Graysville, Alabama has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 11 °C (low) to 23.2 °C (high). Annual precipitation averages 1488.2 Millimeters. Graysville 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 | 0.7 °C | 12.2 °C | 138.43 mm |
| February | 2.2 °C | 14.7 °C | 138.18 mm |
| March | 6.1 °C | 19.2 °C | 147.83 mm |
| April | 10.1 °C | 23.7 °C | 132.33 mm |
| May | 15.2 °C | 27.4 °C | 115.82 mm |
| June | 19.4 °C | 30.8 °C | 123.44 mm |
| July | 21.3 °C | 32.5 °C | 128.27 mm |
| August | 20.9 °C | 32.3 °C | 105.41 mm |
| September | 17.8 °C | 29.8 °C | 114.81 mm |
| October | 11.1 °C | 24.2 °C | 87.63 mm |
| November | 5.2 °C | 18.2 °C | 119.63 mm |
| December | 2.2 °C | 13.5 °C | 136.4 mm |
| Annual | 11 °C | 23.2 °C | 1488.18 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 |