Osakis, Minnesota has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 0.3 °C (low) to 11.1 °C (high). Annual precipitation averages 670.8 Millimeters. Osakis is located in USDA Plant Hardiness Zone 4b. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -16.9 °C | -7 °C | 14.99 mm |
| February | -14.9 °C | -4.2 °C | 13.46 mm |
| March | -7.9 °C | 2.7 °C | 29.97 mm |
| April | -0.1 °C | 11.6 °C | 55.88 mm |
| May | 7.2 °C | 19 °C | 80.77 mm |
| June | 13.1 °C | 24.4 °C | 109.73 mm |
| July | 15.7 °C | 27 °C | 99.57 mm |
| August | 14.1 °C | 25.8 °C | 85.34 mm |
| September | 9.3 °C | 21.3 °C | 69.09 mm |
| October | 2 °C | 12.9 °C | 65.02 mm |
| November | -5.3 °C | 3.6 °C | 27.18 mm |
| December | -12.6 °C | -3.9 °C | 19.81 mm |
| Annual | 0.3 °C | 11.1 °C | 670.81 mm |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 4b : -31.7°C to -28.9°C |
| Plant Hardiness Zone - 2012 | Zone 4a : -34.4°C to -31.7°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |