Mars Hill, Maine has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 30.8 °F (low) to 51.2 °F (high). Annual precipitation averages 43.1 Inches. Mars Hill is located in USDA Plant Hardiness Zone 4a. The growing season typically runs from the last frost around May 21 - May 31 through the first frost around Sep.11 - Sep. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 2.0 °F | 22.1 °F | 3.45 in. |
| February | 3.4 °F | 25.2 °F | 2.57 in. |
| March | 14.9 °F | 35.0 °F | 3.07 in. |
| April | 29.0 °F | 48.6 °F | 3.25 in. |
| May | 40.6 °F | 63.6 °F | 3.58 in. |
| June | 50.1 °F | 73.0 °F | 4.26 in. |
| July | 55.7 °F | 77.9 °F | 3.99 in. |
| August | 53.7 °F | 76.7 °F | 3.63 in. |
| September | 46.2 °F | 68.6 °F | 3.5 in. |
| October | 35.8 °F | 54.5 °F | 4.32 in. |
| November | 25.5 °F | 40.3 °F | 3.68 in. |
| December | 12.2 °F | 28.8 °F | 3.83 in. |
| Annual | 30.8 °F | 51.2 °F | 43.13 in. |
| Average First Frost Date | Sep.11 - Sep. 20 |
| Average Last Frost Date | May 21 - May 31 |
| Average Days With Frost | Over 180 Days |
| Plant Hardiness Zone | Zone 4a : -30°F to -25°F |
| Plant Hardiness Zone - 2012 | Zone 4a : -30°F to -25°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |