Chesterville, Maine has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 33.5 °F (low) to 54.3 °F (high). Annual precipitation averages 48.3 Inches. 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 | 7.5 °F | 27.5 °F | 3.41 in. |
| February | 8.9 °F | 30.6 °F | 3.07 in. |
| March | 19.2 °F | 39.1 °F | 3.58 in. |
| April | 31.2 °F | 52.4 °F | 4.11 in. |
| May | 42.3 °F | 65.2 °F | 3.65 in. |
| June | 51.9 °F | 73.6 °F | 4.99 in. |
| July | 57.4 °F | 79.0 °F | 4.04 in. |
| August | 55.5 °F | 78.2 °F | 3.69 in. |
| September | 47.3 °F | 70.8 °F | 3.58 in. |
| October | 36.8 °F | 57.3 °F | 5.46 in. |
| November | 27.0 °F | 44.6 °F | 4.31 in. |
| December | 16.4 °F | 33.5 °F | 4.38 in. |
| Annual | 33.5 °F | 54.3 °F | 48.27 in. |
| 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 : -20°F to -15°F |
| Plant Hardiness Zone - 2012 | Zone 4b : -25°F to -20°F |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |