Andover, Ohio has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 3.7 °C (low) to 14.5 °C (high). Annual precipitation averages 1269.5 Millimeters. Andover is located in USDA Plant Hardiness Zone 6a. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -8.1 °C | 0.6 °C | 99.57 mm |
| February | -8.1 °C | 1.9 °C | 59.18 mm |
| March | -3.8 °C | 6.8 °C | 89.41 mm |
| April | 2.2 °C | 14.3 °C | 114.05 mm |
| May | 8.1 °C | 20.6 °C | 112.27 mm |
| June | 13.1 °C | 25.1 °C | 140.21 mm |
| July | 15.3 °C | 27.2 °C | 125.22 mm |
| August | 14.3 °C | 26.3 °C | 104.65 mm |
| September | 10.8 °C | 22.9 °C | 118.11 mm |
| October | 5.1 °C | 16.2 °C | 106.68 mm |
| November | 0.1 °C | 9.3 °C | 99.06 mm |
| December | -4.4 °C | 3.3 °C | 101.09 mm |
| Annual | 3.7 °C | 14.5 °C | 1269.5 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 6a : -23.3°C to -20.6°C |
| Plant Hardiness Zone - 2012 | Zone 5b : -26.1°C to -23.3°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |