Forestville, Michigan has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 3.9 °C (low) to 12.1 °C (high). Annual precipitation averages 843.5 Millimeters. Forestville 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. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -8.4 °C | -1.6 °C | 56.13 mm |
| February | -8.5 °C | -0.7 °C | 47.24 mm |
| March | -4.1 °C | 3.8 °C | 50.04 mm |
| April | 1.4 °C | 9.9 °C | 81.28 mm |
| May | 7.3 °C | 16.4 °C | 84.58 mm |
| June | 13 °C | 22 °C | 84.33 mm |
| July | 16.1 °C | 25.2 °C | 76.45 mm |
| August | 15.6 °C | 24.9 °C | 83.82 mm |
| September | 11.8 °C | 21.6 °C | 81.03 mm |
| October | 6.1 °C | 14.7 °C | 76.2 mm |
| November | 0.6 °C | 7.7 °C | 65.02 mm |
| December | -4.4 °C | 1.7 °C | 57.4 mm |
| Annual | 3.9 °C | 12.1 °C | 843.52 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 6a : -23.3°C to -20.6°C |
| Plant Hardiness Zone - 2012 | Zone 6a : -23.3°C to -20.6°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |