Manchester, Maine has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 2 °C (low) to 12.7 °C (high). Annual precipitation averages 1174 Millimeters. Manchester is located in USDA Plant Hardiness Zone 5b. 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 | -12.1 °C | -1.8 °C | 87.88 mm |
| February | -11.1 °C | -0.2 °C | 76.2 mm |
| March | -5.7 °C | 4.5 °C | 92.2 mm |
| April | 0.6 °C | 11.5 °C | 104.9 mm |
| May | 6.6 °C | 18.2 °C | 85.34 mm |
| June | 11.8 °C | 23.1 °C | 107.7 mm |
| July | 15.1 °C | 26.2 °C | 83.82 mm |
| August | 14.3 °C | 25.7 °C | 87.38 mm |
| September | 10 °C | 21.6 °C | 96.77 mm |
| October | 3.9 °C | 14.4 °C | 134.87 mm |
| November | -1.6 °C | 7.6 °C | 108.71 mm |
| December | -7.5 °C | 1.6 °C | 108.2 mm |
| Annual | 2 °C | 12.7 °C | 1173.97 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 5b : -26.1°C to -23.3°C |
| Plant Hardiness Zone - 2012 | Zone 5b : -26.1°C to -23.3°C |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |