Hillsborough, North Carolina has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 9 °C (low) to 21.3 °C (high). Annual precipitation averages 1213.4 Millimeters. Hillsborough is located in USDA Plant Hardiness Zone 8a. The growing season typically runs from the last frost around Apr. 1 - Apr. 10 through the first frost around Nov. 1 - Nov. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -1.6 °C | 10.1 °C | 94.49 mm |
| February | -0.6 °C | 12.1 °C | 75.95 mm |
| March | 3.2 °C | 16.4 °C | 107.95 mm |
| April | 8.1 °C | 21.8 °C | 98.04 mm |
| May | 13.3 °C | 25.6 °C | 97.03 mm |
| June | 17.9 °C | 29.7 °C | 113.28 mm |
| July | 20.2 °C | 31.4 °C | 120.14 mm |
| August | 19.3 °C | 30.6 °C | 107.95 mm |
| September | 16 °C | 27.3 °C | 129.29 mm |
| October | 8.8 °C | 21.9 °C | 88.39 mm |
| November | 2.9 °C | 16.4 °C | 86.61 mm |
| December | 0.1 °C | 11.8 °C | 94.23 mm |
| Annual | 9 °C | 21.3 °C | 1213.35 mm |
| Average First Frost Date | Nov. 1 - Nov. 10 |
| Average Last Frost Date | Apr. 1 - Apr. 10 |
| Average Days With Frost | 75-100 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 | Exceptional Drought |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |