Kennebunk, Maine has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 38.4 °F (low) to 56.2 °F (high). Annual precipitation averages 50 Inches. Kennebunk is located in USDA Plant Hardiness Zone 6a. 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 | 15.2 °F | 32.9 °F | 3.62 in. |
| February | 16.8 °F | 35.1 °F | 3.61 in. |
| March | 25.2 °F | 42.3 °F | 4.55 in. |
| April | 35.3 °F | 53.6 °F | 4.54 in. |
| May | 45.3 °F | 64.0 °F | 3.81 in. |
| June | 55.0 °F | 72.7 °F | 4.4 in. |
| July | 60.9 °F | 78.3 °F | 3.62 in. |
| August | 59.7 °F | 77.6 °F | 3.66 in. |
| September | 52.4 °F | 70.8 °F | 3.92 in. |
| October | 41.2 °F | 59.1 °F | 5.36 in. |
| November | 31.6 °F | 48.7 °F | 4.22 in. |
| December | 22.4 °F | 38.7 °F | 4.66 in. |
| Annual | 38.4 °F | 56.2 °F | 49.97 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 6a : -10°F to -5°F |
| Plant Hardiness Zone - 2012 | Zone 5b : -15°F to -10°F |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |