Fairfield, Maine has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 35 °F (low) to 55.3 °F (high). Annual precipitation averages 43.1 Inches. Fairfield 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 | 9.2 °F | 28.7 °F | 3.03 in. |
| February | 10.6 °F | 31.9 °F | 2.58 in. |
| March | 20.8 °F | 40.5 °F | 3.1 in. |
| April | 32.3 °F | 53.4 °F | 3.7 in. |
| May | 43.3 °F | 65.6 °F | 3.41 in. |
| June | 53.0 °F | 74.3 °F | 4.02 in. |
| July | 58.9 °F | 79.7 °F | 3.41 in. |
| August | 57.3 °F | 78.9 °F | 3.53 in. |
| September | 49.6 °F | 71.3 °F | 3.71 in. |
| October | 38.6 °F | 58.4 °F | 4.94 in. |
| November | 28.8 °F | 45.8 °F | 3.8 in. |
| December | 17.6 °F | 34.7 °F | 3.82 in. |
| Annual | 35 °F | 55.3 °F | 43.05 in. |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 5b : -15°F to -10°F |
| Plant Hardiness Zone - 2012 | Zone 5a : -20°F to -15°F |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |