Onsted, Michigan has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 3.5 °C (low) to 14.7 °C (high). Annual precipitation averages 906.5 Millimeters. Onsted 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 | -9 °C | -0.5 °C | 60.2 mm |
| February | -8.4 °C | 1.3 °C | 51.31 mm |
| March | -3.9 °C | 6.9 °C | 60.71 mm |
| April | 2.2 °C | 14.4 °C | 82.3 mm |
| May | 8.6 °C | 20.9 °C | 101.6 mm |
| June | 13.8 °C | 26.2 °C | 95.76 mm |
| July | 15.8 °C | 28.3 °C | 86.87 mm |
| August | 14.8 °C | 27.2 °C | 85.6 mm |
| September | 10.6 °C | 23.8 °C | 78.99 mm |
| October | 4.4 °C | 16.5 °C | 74.68 mm |
| November | -1 °C | 8.7 °C | 70.61 mm |
| December | -5.5 °C | 2.3 °C | 57.91 mm |
| Annual | 3.5 °C | 14.7 °C | 906.54 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 5b : -26.1°C to -23.3°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |