Cowan, Tennessee has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 8.8 °C (low) to 20.8 °C (high). Annual precipitation averages 1488.7 Millimeters. Cowan 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 | -1.6 °C | 9 °C | 129.79 mm |
| February | -0.2 °C | 11.3 °C | 131.06 mm |
| March | 3.4 °C | 16 °C | 140.97 mm |
| April | 8.2 °C | 21.3 °C | 137.67 mm |
| May | 13.3 °C | 25.5 °C | 117.86 mm |
| June | 17.6 °C | 29.1 °C | 138.18 mm |
| July | 19.6 °C | 30.8 °C | 122.17 mm |
| August | 18.8 °C | 30.6 °C | 103.63 mm |
| September | 15.3 °C | 27.7 °C | 109.73 mm |
| October | 8.6 °C | 22.2 °C | 86.87 mm |
| November | 2.8 °C | 15.8 °C | 111.51 mm |
| December | 0.1 °C | 10.7 °C | 159.26 mm |
| Annual | 8.8 °C | 20.8 °C | 1488.7 mm |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 1 - Apr. 10 |
| Average Days With Frost | 50-75 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 | Normal |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |