Cornville, Maine has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 0.2 °C (low) to 12.1 °C (high). Annual precipitation averages 1135.9 Millimeters. Cornville 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 Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -14.5 °C | -3.1 °C | 81.79 mm |
| February | -13.8 °C | -1.1 °C | 67.56 mm |
| March | -8 °C | 3.8 °C | 85.09 mm |
| April | -1.2 °C | 11 °C | 96.77 mm |
| May | 5.1 °C | 18.3 °C | 89.41 mm |
| June | 10.5 °C | 23.1 °C | 111.76 mm |
| July | 13.6 °C | 26 °C | 94.74 mm |
| August | 12.6 °C | 25.4 °C | 91.69 mm |
| September | 8.1 °C | 21.3 °C | 90.93 mm |
| October | 2.2 °C | 13.7 °C | 125.73 mm |
| November | -3.1 °C | 6.7 °C | 101.6 mm |
| December | -9.6 °C | 0.3 °C | 98.81 mm |
| Annual | 0.2 °C | 12.1 °C | 1135.88 mm |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| 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 |