Richwood, West Virginia has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 38.9 °F (low) to 61.3 °F (high). Annual precipitation averages 55.7 Inches. Richwood is located in USDA Plant Hardiness Zone 6b. The growing season typically runs from the last frost around May 21 - May 31 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 19.4 °F | 39.5 °F | 4.16 in. |
| February | 21.0 °F | 42.6 °F | 4.0 in. |
| March | 27.7 °F | 51.0 °F | 4.99 in. |
| April | 37.0 °F | 63.0 °F | 4.67 in. |
| May | 46.4 °F | 70.9 °F | 5.88 in. |
| June | 54.9 °F | 77.2 °F | 5.76 in. |
| July | 58.8 °F | 80.3 °F | 5.74 in. |
| August | 57.8 °F | 79.3 °F | 4.51 in. |
| September | 51.2 °F | 74.2 °F | 4.17 in. |
| October | 39.7 °F | 64.0 °F | 3.56 in. |
| November | 29.5 °F | 52.0 °F | 3.66 in. |
| December | 23.6 °F | 42.0 °F | 4.61 in. |
| Annual | 38.9 °F | 61.3 °F | 55.71 in. |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 21 - May 31 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 6b : -5°F to 0°F |
| Plant Hardiness Zone - 2012 | Zone 6a : -10°F to -5°F |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |