Middletown, Michigan has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 37.9 °F (low) to 57.5 °F (high). Annual precipitation averages 33.8 Inches. Middletown 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 | 15.5 °F | 30.3 °F | 2.18 in. |
| February | 16.1 °F | 33.0 °F | 1.68 in. |
| March | 24.1 °F | 43.3 °F | 1.97 in. |
| April | 35.0 °F | 56.5 °F | 3.43 in. |
| May | 46.4 °F | 68.7 °F | 4.04 in. |
| June | 56.2 °F | 78.3 °F | 3.43 in. |
| July | 59.5 °F | 82.1 °F | 3.34 in. |
| August | 58.2 °F | 80.0 °F | 3.23 in. |
| September | 50.6 °F | 73.9 °F | 2.86 in. |
| October | 40.1 °F | 60.8 °F | 3.16 in. |
| November | 30.7 °F | 47.1 °F | 2.45 in. |
| December | 22.3 °F | 35.6 °F | 2.03 in. |
| Annual | 37.9 °F | 57.5 °F | 33.8 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 6a : -10°F to -5°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |