Alderson, West Virginia has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 41.8 °F (low) to 65.3 °F (high). Annual precipitation averages 41.2 Inches. Alderson is located in USDA Plant Hardiness Zone 7a. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 22.4 °F | 42.3 °F | 3.1 in. |
| February | 24.6 °F | 46.4 °F | 2.88 in. |
| March | 30.9 °F | 55.4 °F | 3.8 in. |
| April | 39.6 °F | 67.2 °F | 3.62 in. |
| May | 49.4 °F | 75.1 °F | 4.38 in. |
| June | 58.1 °F | 81.5 °F | 3.95 in. |
| July | 62.2 °F | 84.7 °F | 4.28 in. |
| August | 61.1 °F | 83.8 °F | 3.18 in. |
| September | 54.3 °F | 78.1 °F | 3.31 in. |
| October | 41.8 °F | 67.8 °F | 2.64 in. |
| November | 31.3 °F | 56.2 °F | 2.56 in. |
| December | 25.9 °F | 45.4 °F | 3.49 in. |
| Annual | 41.8 °F | 65.3 °F | 41.19 in. |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 125-150 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 | Dfb - Humid Continental Mild Summer, Wet All Year |