Marion, Michigan has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 0.8 °C (low) to 12.6 °C (high). Annual precipitation averages 879.1 Millimeters. Marion 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 | -11.4 °C | -2.7 °C | 56.64 mm |
| February | -11.7 °C | -1.1 °C | 42.93 mm |
| March | -7.3 °C | 4.7 °C | 52.07 mm |
| April | -0.9 °C | 11.8 °C | 89.92 mm |
| May | 5.7 °C | 19.2 °C | 91.69 mm |
| June | 10.9 °C | 24.6 °C | 89.41 mm |
| July | 12.9 °C | 26.9 °C | 78.99 mm |
| August | 11.8 °C | 25.8 °C | 85.85 mm |
| September | 7.4 °C | 21.7 °C | 77.98 mm |
| October | 2.1 °C | 13.8 °C | 91.69 mm |
| November | -2.7 °C | 6.3 °C | 67.56 mm |
| December | -7.4 °C | 0.2 °C | 54.36 mm |
| Annual | 0.8 °C | 12.6 °C | 879.09 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 |