Jonesborough, Tennessee has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 7.3 °C (low) to 20 °C (high). Annual precipitation averages 1182.4 Millimeters. Jonesborough is located in USDA Plant Hardiness Zone 7a. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -3 °C | 8.2 °C | 91.69 mm |
| February | -1.6 °C | 10.4 °C | 95.25 mm |
| March | 1.9 °C | 15.3 °C | 104.9 mm |
| April | 6.4 °C | 20.9 °C | 106.68 mm |
| May | 11.4 °C | 24.8 °C | 106.43 mm |
| June | 15.8 °C | 28.2 °C | 106.43 mm |
| July | 17.8 °C | 29.7 °C | 133.1 mm |
| August | 17.2 °C | 29.3 °C | 111.51 mm |
| September | 13.8 °C | 26.8 °C | 77.72 mm |
| October | 7.3 °C | 21.4 °C | 65.79 mm |
| November | 1.7 °C | 15.2 °C | 77.98 mm |
| December | -1.3 °C | 9.9 °C | 104.9 mm |
| Annual | 7.3 °C | 20 °C | 1182.38 mm |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 75-100 Days |
| Plant Hardiness Zone | Zone 7a : -17.8°C to -15°C |
| Plant Hardiness Zone - 2012 | Zone 7a : -17.8°C to -15°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |