Hartland, Michigan has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 38.1 °F (low) to 57.1 °F (high). Annual precipitation averages 34 Inches. Hartland 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 | 30.0 °F | 2.35 in. |
| February | 15.8 °F | 32.9 °F | 1.82 in. |
| March | 24.2 °F | 43.3 °F | 2.13 in. |
| April | 35.4 °F | 56.2 °F | 3.16 in. |
| May | 46.7 °F | 68.2 °F | 3.8 in. |
| June | 56.2 °F | 77.5 °F | 3.62 in. |
| July | 59.9 °F | 81.4 °F | 3.33 in. |
| August | 58.7 °F | 79.7 °F | 3.36 in. |
| September | 51.5 °F | 73.4 °F | 2.98 in. |
| October | 40.4 °F | 60.3 °F | 2.83 in. |
| November | 30.7 °F | 46.9 °F | 2.49 in. |
| December | 21.9 °F | 35.2 °F | 2.16 in. |
| Annual | 38.1 °F | 57.1 °F | 34.03 in. |
| 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 6a : -10°F to -5°F |
| Plant Hardiness Zone - 2012 | Zone 5b : -15°F to -10°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |