Round Hill, Virginia has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 43.1 °F (low) to 65.3 °F (high). Annual precipitation averages 43.7 Inches. Round Hill is located in USDA Plant Hardiness Zone 7a. The growing season typically runs from the last frost around Apr. 11 - Apr. 20 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 23.1 °F | 42.0 °F | 3.0 in. |
| February | 24.8 °F | 45.4 °F | 2.33 in. |
| March | 31.2 °F | 53.6 °F | 3.71 in. |
| April | 41.2 °F | 65.7 °F | 3.67 in. |
| May | 50.7 °F | 74.2 °F | 4.61 in. |
| June | 59.7 °F | 82.4 °F | 4.45 in. |
| July | 64.3 °F | 87.0 °F | 3.82 in. |
| August | 62.5 °F | 85.3 °F | 3.2 in. |
| September | 55.3 °F | 78.7 °F | 4.71 in. |
| October | 43.3 °F | 67.5 °F | 3.56 in. |
| November | 33.8 °F | 55.9 °F | 3.06 in. |
| December | 26.8 °F | 45.8 °F | 3.54 in. |
| Annual | 43.1 °F | 65.3 °F | 43.66 in. |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 100-125 Days |
| Plant Hardiness Zone | Zone 7a : 0°F to 5°F |
| Plant Hardiness Zone - 2012 | Zone 7a : 0°F to 5°F |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |