Port Royal, Virginia has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 47 °F (low) to 68.1 °F (high). Annual precipitation averages 44.6 Inches. Port Royal is located in USDA Plant Hardiness Zone 7b. The growing season typically runs from the last frost around Apr. 1 - Apr. 10 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 27.9 °F | 46.2 °F | 3.13 in. |
| February | 29.1 °F | 49.5 °F | 2.74 in. |
| March | 35.7 °F | 57.3 °F | 3.87 in. |
| April | 44.3 °F | 66.7 °F | 3.29 in. |
| May | 54.1 °F | 76.6 °F | 4.01 in. |
| June | 63.5 °F | 84.7 °F | 4.23 in. |
| July | 68.2 °F | 89.1 °F | 4.37 in. |
| August | 64.7 °F | 86.9 °F | 4.04 in. |
| September | 59.9 °F | 80.8 °F | 4.31 in. |
| October | 47.9 °F | 70.2 °F | 3.7 in. |
| November | 37.5 °F | 59.2 °F | 3.24 in. |
| December | 31.0 °F | 50.1 °F | 3.64 in. |
| Annual | 47 °F | 68.1 °F | 44.57 in. |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 1 - Apr. 10 |
| Average Days With Frost | 75-100 Days |
| Plant Hardiness Zone | Zone 7b : 5°F to 10°F |
| Plant Hardiness Zone - 2012 | Zone 7b : 5°F to 10°F |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |