Greenbrier, Tennessee has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 47.4 °F (low) to 68.1 °F (high). Annual precipitation averages 53.4 Inches. Greenbrier 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. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 26.4 °F | 44.7 °F | 4.07 in. |
| February | 29.7 °F | 49.5 °F | 4.56 in. |
| March | 37.2 °F | 58.4 °F | 4.86 in. |
| April | 46.6 °F | 68.9 °F | 5.14 in. |
| May | 56.5 °F | 77.2 °F | 5.55 in. |
| June | 64.2 °F | 84.4 °F | 4.31 in. |
| July | 67.5 °F | 87.4 °F | 4.61 in. |
| August | 66.0 °F | 88.0 °F | 3.76 in. |
| September | 59.3 °F | 81.7 °F | 4.05 in. |
| October | 47.5 °F | 70.6 °F | 3.81 in. |
| November | 37.4 °F | 58.3 °F | 3.76 in. |
| December | 30.7 °F | 48.3 °F | 4.87 in. |
| Annual | 47.4 °F | 68.1 °F | 53.35 in. |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 75-100 Days |
| Plant Hardiness Zone | Zone 7a : 0°F to 5°F |
| Plant Hardiness Zone - 2012 | Zone 7a : 0°F to 5°F |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |