Jamestown, Tennessee has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 7.2 °C (low) to 18.8 °C (high). Annual precipitation averages 1502.2 Millimeters. Jamestown is located in USDA Plant Hardiness Zone 7a. The growing season typically runs from the last frost around Apr. 11 - Apr. 20 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -3.9 °C | 6.7 °C | 128.78 mm |
| February | -2.1 °C | 9.2 °C | 116.84 mm |
| March | 1.5 °C | 13.9 °C | 142.24 mm |
| April | 6.4 °C | 19.5 °C | 139.7 mm |
| May | 11.8 °C | 23.7 °C | 134.62 mm |
| June | 16 °C | 27.1 °C | 140.72 mm |
| July | 18 °C | 28.7 °C | 144.02 mm |
| August | 17.3 °C | 28.5 °C | 114.05 mm |
| September | 13.8 °C | 25.8 °C | 104.39 mm |
| October | 7.2 °C | 20.4 °C | 81.53 mm |
| November | 1.8 °C | 13.7 °C | 103.38 mm |
| December | -1.6 °C | 8.6 °C | 151.89 mm |
| Annual | 7.2 °C | 18.8 °C | 1502.16 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 75-100 Days |
| Plant Hardiness Zone | Zone 7a : -17.8°C to -15°C |
| Plant Hardiness Zone - 2012 | Zone 6b : -20.6°C to -17.8°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |