Hartford, Alabama has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 12.8 °C (low) to 25.2 °C (high). Annual precipitation averages 1536.7 Millimeters. Hartford is located in USDA Plant Hardiness Zone 8b. The growing season typically runs from the last frost around Mar. 1 - Mar. 10 through the first frost around Nov. 11 - Nov. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 3.3 °C | 15.8 °C | 128.27 mm |
| February | 4.9 °C | 17.8 °C | 135.64 mm |
| March | 8.1 °C | 21.8 °C | 140.46 mm |
| April | 11.8 °C | 25.4 °C | 127.51 mm |
| May | 16.7 °C | 29.5 °C | 103.63 mm |
| June | 20.8 °C | 31.9 °C | 140.97 mm |
| July | 22.1 °C | 32.9 °C | 159.26 mm |
| August | 21.7 °C | 32.4 °C | 144.78 mm |
| September | 19.2 °C | 30.7 °C | 127.25 mm |
| October | 13.2 °C | 26.2 °C | 82.8 mm |
| November | 7.2 °C | 20.8 °C | 113.28 mm |
| December | 4.7 °C | 16.9 °C | 132.84 mm |
| Annual | 12.8 °C | 25.2 °C | 1536.69 mm |
| Average First Frost Date | Nov. 11 - Nov. 20 |
| Average Last Frost Date | Mar. 1 - Mar. 10 |
| Average Days With Frost | 20-30 Days |
| Plant Hardiness Zone | Zone 8b : -9.4°C to -6.7°C |
| Plant Hardiness Zone - 2012 | Zone 8b : -9.4°C to -6.7°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |