Falmouth, Michigan has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 0.6 °C (low) to 12.3 °C (high). Annual precipitation averages 856 Millimeters. Falmouth is located in USDA Plant Hardiness Zone 5a. The growing season typically runs from the last frost around May 21 - May 31 through the first frost around Sep. 21 - Sep. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -11.8 °C | -2.9 °C | 51.05 mm |
| February | -12.1 °C | -1.3 °C | 40.39 mm |
| March | -7.7 °C | 4.4 °C | 49.28 mm |
| April | -1.1 °C | 11.4 °C | 87.12 mm |
| May | 5.5 °C | 18.9 °C | 90.42 mm |
| June | 10.8 °C | 24.3 °C | 87.38 mm |
| July | 12.8 °C | 26.7 °C | 78.74 mm |
| August | 11.8 °C | 25.6 °C | 82.3 mm |
| September | 7.4 °C | 21.4 °C | 77.22 mm |
| October | 2.2 °C | 13.6 °C | 92.46 mm |
| November | -2.8 °C | 6.1 °C | 66.29 mm |
| December | -7.7 °C | -0.1 °C | 53.34 mm |
| Annual | 0.6 °C | 12.3 °C | 855.99 mm |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| Average Last Frost Date | May 21 - May 31 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 5a : -28.9°C to -26.1°C |
| Plant Hardiness Zone - 2012 | Zone 5a : -28.9°C to -26.1°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |