Grayson Valley, Alabama has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 52.6 °F (low) to 71.8 °F (high). Annual precipitation averages 58 Inches. Grayson Valley 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 | 33.7 °F | 52.2 °F | 5.26 in. |
| February | 36.6 °F | 56.5 °F | 5.15 in. |
| March | 43.7 °F | 64.8 °F | 5.76 in. |
| April | 51.2 °F | 72.6 °F | 5.15 in. |
| May | 60.1 °F | 79.3 °F | 4.85 in. |
| June | 67.9 °F | 85.5 °F | 4.85 in. |
| July | 71.0 °F | 88.5 °F | 5.11 in. |
| August | 70.1 °F | 88.1 °F | 4.09 in. |
| September | 64.5 °F | 83.5 °F | 4.55 in. |
| October | 53.2 °F | 73.5 °F | 3.41 in. |
| November | 42.4 °F | 62.9 °F | 4.72 in. |
| December | 36.4 °F | 54.6 °F | 5.06 in. |
| Annual | 52.6 °F | 71.8 °F | 57.96 in. |
| 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 : 10°F to 15°F |
| Plant Hardiness Zone - 2012 | Zone 7b : 5°F to 10°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |