Hillsboro, Alabama has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 10 °C (low) to 21.9 °C (high). Annual precipitation averages 1501.4 Millimeters. Hillsboro 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 Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -0.5 °C | 10.2 °C | 138.43 mm |
| February | 1 °C | 12.6 °C | 140.21 mm |
| March | 4.9 °C | 17.4 °C | 137.92 mm |
| April | 9.3 °C | 22.2 °C | 134.87 mm |
| May | 14.6 °C | 26.4 °C | 124.21 mm |
| June | 18.9 °C | 30.3 °C | 117.6 mm |
| July | 20.7 °C | 31.6 °C | 126.75 mm |
| August | 19.9 °C | 31.6 °C | 107.19 mm |
| September | 16.4 °C | 29.1 °C | 107.7 mm |
| October | 9.8 °C | 23.3 °C | 97.03 mm |
| November | 3.9 °C | 16.8 °C | 112.01 mm |
| December | 0.9 °C | 11.8 °C | 157.48 mm |
| Annual | 10 °C | 21.9 °C | 1501.4 mm |
| 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 8a : -12.2°C to -9.4°C |
| Plant Hardiness Zone - 2012 | Zone 7b : -15°C to -12.2°C |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |