Nitro, West Virginia has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 6.3 °C (low) to 19.1 °C (high). Annual precipitation averages 1132.1 Millimeters. Nitro 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 | -4.8 °C | 5.9 °C | 85.6 mm |
| February | -3.7 °C | 8.1 °C | 75.44 mm |
| March | -0.2 °C | 13.2 °C | 103.38 mm |
| April | 5.1 °C | 20.2 °C | 91.44 mm |
| May | 10.9 °C | 24.4 °C | 118.11 mm |
| June | 15.6 °C | 28.3 °C | 108.46 mm |
| July | 17.9 °C | 30.2 °C | 131.32 mm |
| August | 17.2 °C | 29.6 °C | 91.69 mm |
| September | 13.2 °C | 26.6 °C | 84.84 mm |
| October | 6.4 °C | 20.3 °C | 75.95 mm |
| November | 0.6 °C | 13.7 °C | 73.41 mm |
| December | -2.5 °C | 8.1 °C | 92.46 mm |
| Annual | 6.3 °C | 19.1 °C | 1132.1 mm |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 75-100 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 | Cfa - Humid Subtropical Climate |