Grand Junction, Tennessee has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 49 °F (low) to 71.6 °F (high). Annual precipitation averages 56.8 Inches. Grand Junction is located in USDA Plant Hardiness Zone 7b. The growing season typically runs from the last frost around Mar. 21 - Mar. 31 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 29.5 °F | 49.5 °F | 4.54 in. |
| February | 32.4 °F | 54.2 °F | 4.93 in. |
| March | 39.5 °F | 62.7 °F | 5.67 in. |
| April | 47.8 °F | 72.3 °F | 5.69 in. |
| May | 57.6 °F | 79.9 °F | 5.38 in. |
| June | 65.5 °F | 87.2 °F | 4.66 in. |
| July | 68.9 °F | 90.1 °F | 4.64 in. |
| August | 67.2 °F | 90.0 °F | 3.42 in. |
| September | 60.3 °F | 84.8 °F | 3.96 in. |
| October | 48.3 °F | 74.2 °F | 4.13 in. |
| November | 38.4 °F | 61.8 °F | 4.08 in. |
| December | 32.6 °F | 52.2 °F | 5.68 in. |
| Annual | 49 °F | 71.6 °F | 56.78 in. |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Mar. 21 - Mar. 31 |
| Average Days With Frost | 50-75 Days |
| Plant Hardiness Zone | Zone 7b : 5°F to 10°F |
| Plant Hardiness Zone - 2012 | Zone 7b : 5°F to 10°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |