McMechen, West Virginia has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 42.9 °F (low) to 63.4 °F (high). Annual precipitation averages 42.8 Inches. McMechen is located in USDA Plant Hardiness Zone 6b. 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 | 22.1 °F | 38.6 °F | 3.45 in. |
| February | 23.8 °F | 41.6 °F | 2.85 in. |
| March | 30.4 °F | 51.3 °F | 3.52 in. |
| April | 40.4 °F | 64.3 °F | 3.6 in. |
| May | 50.8 °F | 73.7 °F | 4.33 in. |
| June | 59.6 °F | 81.5 °F | 4.53 in. |
| July | 64.0 °F | 84.8 °F | 4.12 in. |
| August | 62.6 °F | 83.8 °F | 3.54 in. |
| September | 55.6 °F | 78.0 °F | 3.69 in. |
| October | 43.9 °F | 66.1 °F | 3.04 in. |
| November | 33.9 °F | 53.6 °F | 2.94 in. |
| December | 27.5 °F | 42.9 °F | 3.22 in. |
| Annual | 42.9 °F | 63.4 °F | 42.83 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 6b : -5°F to 0°F |
| Plant Hardiness Zone - 2012 | Zone 6b : -5°F to 0°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |