Andover, South Dakota has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 0.5 °C (low) to 12.3 °C (high). Annual precipitation averages 606.3 Millimeters. Andover is located in USDA Plant Hardiness Zone 4b. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -16.3 °C | -5.9 °C | 14.73 mm |
| February | -13.9 °C | -3 °C | 14.22 mm |
| March | -7.2 °C | 3.9 °C | 27.69 mm |
| April | -0.1 °C | 12.7 °C | 57.4 mm |
| May | 7.2 °C | 19.9 °C | 80.26 mm |
| June | 13.3 °C | 25.2 °C | 105.16 mm |
| July | 15.8 °C | 27.9 °C | 94.23 mm |
| August | 14.6 °C | 27.3 °C | 59.94 mm |
| September | 9.6 °C | 22.8 °C | 59.44 mm |
| October | 1.8 °C | 14.4 °C | 54.36 mm |
| November | -5.8 °C | 4.8 °C | 21.34 mm |
| December | -12.6 °C | -2.8 °C | 17.53 mm |
| Annual | 0.5 °C | 12.3 °C | 606.3 mm |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 4b : -31.7°C to -28.9°C |
| Plant Hardiness Zone - 2012 | Zone 4a : -34.4°C to -31.7°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |