Keller, Virginia has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 10.1 °C (low) to 19.7 °C (high). Annual precipitation averages 1192 Millimeters. Keller is located in USDA Plant Hardiness Zone 8a. The growing season typically runs from the last frost around Apr. 1 - Apr. 10 through the first frost around Nov. 1 - Nov. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -0.8 °C | 8.7 °C | 88.9 mm |
| February | -0.2 °C | 9.8 °C | 77.22 mm |
| March | 3.2 °C | 13.3 °C | 101.85 mm |
| April | 8.6 °C | 18.8 °C | 85.85 mm |
| May | 13.8 °C | 23.6 °C | 92.2 mm |
| June | 18.8 °C | 28.2 °C | 105.41 mm |
| July | 21.6 °C | 30.6 °C | 120.9 mm |
| August | 20.4 °C | 29.4 °C | 116.84 mm |
| September | 17.3 °C | 26.6 °C | 109.47 mm |
| October | 11.2 °C | 21.2 °C | 110.24 mm |
| November | 5.3 °C | 15.4 °C | 83.31 mm |
| December | 1.6 °C | 11 °C | 99.82 mm |
| Annual | 10.1 °C | 19.7 °C | 1192.01 mm |
| Average First Frost Date | Nov. 1 - Nov. 10 |
| Average Last Frost Date | Apr. 1 - Apr. 10 |
| Average Days With Frost | 50-75 Days |
| Plant Hardiness Zone | Zone 8a : -12.2°C to -9.4°C |
| Plant Hardiness Zone - 2012 | Zone 8a : -12.2°C to -9.4°C |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |