Chesterville, Maine has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 0.8 °C (low) to 12.4 °C (high). Annual precipitation averages 1226.1 Millimeters. Chesterville is located in USDA Plant Hardiness Zone 5a. The growing season typically runs from the last frost around May 11 - May 20 through the first frost around Sep. 21 - Sep. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -13.6 °C | -2.5 °C | 86.61 mm |
| February | -12.8 °C | -0.8 °C | 77.98 mm |
| March | -7.1 °C | 3.9 °C | 90.93 mm |
| April | -0.4 °C | 11.3 °C | 104.39 mm |
| May | 5.7 °C | 18.4 °C | 92.71 mm |
| June | 11.1 °C | 23.1 °C | 126.75 mm |
| July | 14.1 °C | 26.1 °C | 102.62 mm |
| August | 13.1 °C | 25.7 °C | 93.73 mm |
| September | 8.5 °C | 21.6 °C | 90.93 mm |
| October | 2.7 °C | 14.1 °C | 138.68 mm |
| November | -2.8 °C | 7 °C | 109.47 mm |
| December | -8.7 °C | 0.8 °C | 111.25 mm |
| Annual | 0.8 °C | 12.4 °C | 1226.05 mm |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| Average Last Frost Date | May 11 - May 20 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 5a : -28.9°C to -26.1°C |
| Plant Hardiness Zone - 2012 | Zone 4b : -31.7°C to -28.9°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |