Hillsboro, Virginia has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 6.2 °C (low) to 18.2 °C (high). Annual precipitation averages 1095 Millimeters. Hillsboro is located in USDA Plant Hardiness Zone 7a. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -4.9 °C | 5.2 °C | 76.71 mm |
| February | -3.8 °C | 7.1 °C | 60.2 mm |
| March | -0.3 °C | 11.7 °C | 92.2 mm |
| April | 5 °C | 18.4 °C | 90.42 mm |
| May | 10.4 °C | 23.3 °C | 114.3 mm |
| June | 15.2 °C | 27.8 °C | 106.93 mm |
| July | 17.9 °C | 30.3 °C | 100.33 mm |
| August | 16.7 °C | 29.3 °C | 82.55 mm |
| September | 12.9 °C | 25.6 °C | 118.36 mm |
| October | 6.3 °C | 19.4 °C | 87.88 mm |
| November | 1.3 °C | 12.9 °C | 76.96 mm |
| December | -2.8 °C | 7.3 °C | 88.14 mm |
| Annual | 6.2 °C | 18.2 °C | 1094.98 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 100-125 Days |
| Plant Hardiness Zone | Zone 7a : -17.8°C to -15°C |
| Plant Hardiness Zone - 2012 | Zone 7a : -17.8°C to -15°C |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |