Cohasset, Minnesota has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from -1.4 °C (low) to 10.3 °C (high). Annual precipitation averages 712.7 Millimeters. Cohasset is located in USDA Plant Hardiness Zone 4a. The growing season typically runs from the last frost around May 21 - May 31 through the first frost around Sep.11 - Sep. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -18.8 °C | -7.8 °C | 20.83 mm |
| February | -17 °C | -4.2 °C | 18.54 mm |
| March | -9.6 °C | 3.1 °C | 29.21 mm |
| April | -1.9 °C | 10.8 °C | 49.02 mm |
| May | 5.1 °C | 18.3 °C | 80.26 mm |
| June | 10.9 °C | 23.3 °C | 112.01 mm |
| July | 13.6 °C | 25.8 °C | 106.68 mm |
| August | 12.3 °C | 24.9 °C | 86.61 mm |
| September | 7.8 °C | 20.1 °C | 81.53 mm |
| October | 1.3 °C | 11.8 °C | 67.06 mm |
| November | -6.1 °C | 2.4 °C | 35.31 mm |
| December | -13.9 °C | -4.9 °C | 25.65 mm |
| Annual | -1.4 °C | 10.3 °C | 712.71 mm |
| Average First Frost Date | Sep.11 - Sep. 20 |
| Average Last Frost Date | May 21 - May 31 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 4a : -34.4°C to -31.7°C |
| Plant Hardiness Zone - 2012 | Zone 3b : -37.2°C to -34.4°C |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |