Acton, Maine has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 36.2 °F (low) to 56.1 °F (high). Annual precipitation averages 49.9 Inches. Acton is located in USDA Plant Hardiness Zone 5b. 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 | 13.1 °F | 29.9 °F | 3.47 in. |
| February | 13.0 °F | 32.9 °F | 3.66 in. |
| March | 21.5 °F | 41.1 °F | 4.21 in. |
| April | 32.8 °F | 54.9 °F | 4.34 in. |
| May | 44.0 °F | 67.2 °F | 3.71 in. |
| June | 54.2 °F | 76.1 °F | 4.47 in. |
| July | 59.1 °F | 81.4 °F | 4.2 in. |
| August | 57.8 °F | 79.5 °F | 3.94 in. |
| September | 50.1 °F | 71.4 °F | 3.86 in. |
| October | 39.7 °F | 57.9 °F | 5.14 in. |
| November | 29.5 °F | 46.0 °F | 4.23 in. |
| December | 19.4 °F | 35.4 °F | 4.69 in. |
| Annual | 36.2 °F | 56.1 °F | 49.92 in. |
| 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 5b : -15°F to -10°F |
| Plant Hardiness Zone - 2012 | Zone 5a : -20°F to -15°F |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |