Andover, Massachusetts has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 3.8 °C (low) to 15.2 °C (high). Annual precipitation averages 1208.5 Millimeters. Andover is located in USDA Plant Hardiness Zone 6b. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -8.7 °C | 1.7 °C | 91.19 mm |
| February | -7.6 °C | 3.2 °C | 86.11 mm |
| March | -3.5 °C | 7.2 °C | 117.86 mm |
| April | 2.3 °C | 14.2 °C | 100.33 mm |
| May | 7.9 °C | 19.9 °C | 95.25 mm |
| June | 13.1 °C | 24.9 °C | 109.47 mm |
| July | 16.4 °C | 28.2 °C | 92.96 mm |
| August | 15.5 °C | 27.4 °C | 88.14 mm |
| September | 11.3 °C | 23.5 °C | 95.25 mm |
| October | 4.7 °C | 16.6 °C | 120.9 mm |
| November | -0.3 °C | 10.6 °C | 96.01 mm |
| December | -5.1 °C | 4.8 °C | 115.06 mm |
| Annual | 3.8 °C | 15.2 °C | 1208.53 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 100-125 Days |
| Plant Hardiness Zone | Zone 6b : -20.6°C to -17.8°C |
| Plant Hardiness Zone - 2012 | Zone 6a : -23.3°C to -20.6°C |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |