Chesterfield, Massachusetts has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 1.7 °C (low) to 13.1 °C (high). Annual precipitation averages 1323.9 Millimeters. Chesterfield is located in USDA Plant Hardiness Zone 6a. The growing season typically runs from the last frost around May 21 - May 31 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -10.9 °C | -0.9 °C | 92.2 mm |
| February | -10.4 °C | 0.6 °C | 86.87 mm |
| March | -6.1 °C | 5.1 °C | 104.9 mm |
| April | -0.1 °C | 12.4 °C | 104.65 mm |
| May | 6.1 °C | 18.8 °C | 106.17 mm |
| June | 11.2 °C | 23.4 °C | 127.51 mm |
| July | 14.3 °C | 26.3 °C | 114.05 mm |
| August | 13.3 °C | 25.3 °C | 109.98 mm |
| September | 9.1 °C | 21.4 °C | 130.3 mm |
| October | 3.1 °C | 14.6 °C | 132.59 mm |
| November | -2.4 °C | 7.8 °C | 100.84 mm |
| December | -7.4 °C | 1.9 °C | 113.79 mm |
| Annual | 1.7 °C | 13.1 °C | 1323.85 mm |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 21 - May 31 |
| 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 | Moderate Drought |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |