Graysville, Tennessee has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 8.8 °C (low) to 21.2 °C (high). Annual precipitation averages 1536.5 Millimeters. Graysville is located in USDA Plant Hardiness Zone 7b. The growing season typically runs from the last frost around Apr. 1 - Apr. 10 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -1.8 °C | 9.2 °C | 137.67 mm |
| February | -0.3 °C | 11.8 °C | 131.32 mm |
| March | 3.2 °C | 16.6 °C | 141.99 mm |
| April | 7.7 °C | 21.8 °C | 137.67 mm |
| May | 13.1 °C | 25.9 °C | 123.7 mm |
| June | 17.7 °C | 29.7 °C | 118.62 mm |
| July | 19.9 °C | 31.3 °C | 147.83 mm |
| August | 19.2 °C | 31.2 °C | 104.39 mm |
| September | 15.6 °C | 28.2 °C | 121.92 mm |
| October | 8.6 °C | 22.3 °C | 90.93 mm |
| November | 2.4 °C | 15.9 °C | 122.94 mm |
| December | -0.2 °C | 10.7 °C | 157.48 mm |
| Annual | 8.8 °C | 21.2 °C | 1536.46 mm |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 1 - Apr. 10 |
| Average Days With Frost | 75-100 Days |
| Plant Hardiness Zone | Zone 7b : -15°C to -12.2°C |
| Plant Hardiness Zone - 2012 | Zone 7b : -15°C to -12.2°C |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |