Chattanooga, Tennessee has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 9.6 °C (low) to 21.9 °C (high). Annual precipitation averages 1422.9 Millimeters. Chattanooga is located in USDA Plant Hardiness Zone 8a. The growing season typically runs from the last frost around Mar. 21 - Mar. 31 through the first frost around Nov. 1 - Nov. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -0.9 °C | 10.1 °C | 136.65 mm |
| February | 0.6 °C | 12.7 °C | 123.95 mm |
| March | 4.2 °C | 17.3 °C | 137.41 mm |
| April | 8.6 °C | 22.5 °C | 124.21 mm |
| May | 13.8 °C | 26.6 °C | 104.14 mm |
| June | 18.3 °C | 30.2 °C | 102.87 mm |
| July | 20.5 °C | 31.9 °C | 120.4 mm |
| August | 20 °C | 31.7 °C | 96.52 mm |
| September | 16.4 °C | 28.8 °C | 120.4 mm |
| October | 9.4 °C | 23.1 °C | 90.93 mm |
| November | 3.2 °C | 16.6 °C | 120.65 mm |
| December | 0.6 °C | 11.7 °C | 144.78 mm |
| Annual | 9.6 °C | 21.9 °C | 1422.91 mm |
| Average First Frost Date | Nov. 1 - Nov. 10 |
| Average Last Frost Date | Mar. 21 - Mar. 31 |
| Average Days With Frost | 50-75 Days |
| Plant Hardiness Zone | Zone 8a : -12.2°C to -9.4°C |
| Plant Hardiness Zone - 2012 | Zone 7b : -15°C to -12.2°C |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |