Harpers Ferry, West Virginia has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 43.4 °F (low) to 65.4 °F (high). Annual precipitation averages 41.8 Inches. Harpers Ferry 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. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 23.4 °F | 41.7 °F | 3.07 in. |
| February | 24.8 °F | 45.2 °F | 2.4 in. |
| March | 31.5 °F | 53.6 °F | 3.49 in. |
| April | 41.6 °F | 65.6 °F | 3.32 in. |
| May | 51.5 °F | 74.5 °F | 4.25 in. |
| June | 60.1 °F | 82.7 °F | 3.87 in. |
| July | 64.4 °F | 87.2 °F | 3.98 in. |
| August | 62.5 °F | 85.5 °F | 3.24 in. |
| September | 55.8 °F | 78.8 °F | 4.39 in. |
| October | 43.9 °F | 67.7 °F | 3.35 in. |
| November | 34.1 °F | 56.1 °F | 3.09 in. |
| December | 27.2 °F | 45.6 °F | 3.32 in. |
| Annual | 43.4 °F | 65.4 °F | 41.77 in. |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| 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 6b : -5°F to 0°F |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |