Gorham, Maine has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 2.2 °C (low) to 13.6 °C (high). Annual precipitation averages 1261.1 Millimeters. Gorham is located in USDA Plant Hardiness Zone 5b. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -11.4 °C | -0.6 °C | 88.65 mm |
| February | -10.8 °C | 1.1 °C | 89.92 mm |
| March | -5.6 °C | 5.6 °C | 106.43 mm |
| April | 0.6 °C | 12.4 °C | 114.55 mm |
| May | 6.5 °C | 18.8 °C | 93.98 mm |
| June | 12.1 °C | 23.7 °C | 113.28 mm |
| July | 15.3 °C | 26.8 °C | 95 mm |
| August | 14.4 °C | 26.4 °C | 89.92 mm |
| September | 10.1 °C | 22.2 °C | 99.06 mm |
| October | 3.8 °C | 15.2 °C | 140.97 mm |
| November | -1.6 °C | 8.4 °C | 110.49 mm |
| December | -7.3 °C | 2.6 °C | 118.87 mm |
| Annual | 2.2 °C | 13.6 °C | 1261.12 mm |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 1 - May 10 |
| 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 |