Kilmarnock, Virginia has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 50.2 °F (low) to 68.5 °F (high). Annual precipitation averages 48.4 Inches. Kilmarnock 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 | 30.1 °F | 48.0 °F | 3.53 in. |
| February | 30.9 °F | 50.5 °F | 2.84 in. |
| March | 36.8 °F | 57.7 °F | 4.26 in. |
| April | 46.9 °F | 68.1 °F | 3.42 in. |
| May | 56.8 °F | 75.9 °F | 3.88 in. |
| June | 66.0 °F | 83.9 °F | 4.41 in. |
| July | 70.8 °F | 88.4 °F | 4.95 in. |
| August | 69.8 °F | 86.0 °F | 5.22 in. |
| September | 64.3 °F | 80.7 °F | 4.82 in. |
| October | 53.3 °F | 70.7 °F | 4.13 in. |
| November | 42.3 °F | 60.5 °F | 3.11 in. |
| December | 34.6 °F | 52.1 °F | 3.79 in. |
| Annual | 50.2 °F | 68.5 °F | 48.36 in. |
| Average First Frost Date | Nov. 1 - Nov. 10 |
| Average Last Frost Date | Apr. 1 - Apr. 10 |
| Average Days With Frost | 50-75 Days |
| Plant Hardiness Zone | Zone 8a : 10°F to 15°F |
| Plant Hardiness Zone - 2012 | Zone 7b : 5°F to 10°F |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |