Clay, West Virginia has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 5.9 °C (low) to 18.7 °C (high). Annual precipitation averages 1247.1 Millimeters. Clay 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 | -5.2 °C | 5.7 °C | 90.68 mm |
| February | -4.1 °C | 7.8 °C | 87.63 mm |
| March | -0.4 °C | 12.9 °C | 111.25 mm |
| April | 4.6 °C | 19.8 °C | 101.6 mm |
| May | 10.4 °C | 24.2 °C | 124.71 mm |
| June | 14.9 °C | 27.9 °C | 126.75 mm |
| July | 17.3 °C | 29.8 °C | 139.19 mm |
| August | 16.4 °C | 29.1 °C | 107.44 mm |
| September | 12.8 °C | 26.1 °C | 96.01 mm |
| October | 6.1 °C | 19.7 °C | 83.57 mm |
| November | 0.2 °C | 13.2 °C | 78.99 mm |
| December | -2.6 °C | 7.8 °C | 99.31 mm |
| Annual | 5.9 °C | 18.7 °C | 1247.13 mm |
| 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 : -17.8°C to -15°C |
| Plant Hardiness Zone - 2012 | Zone 6b : -20.6°C to -17.8°C |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |