Cosmos, Minnesota has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 34.2 °F (low) to 53.8 °F (high). Annual precipitation averages 30.1 Inches. Cosmos 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 | 3.9 °F | 21.4 °F | 0.74 in. |
| February | 7.1 °F | 25.9 °F | 0.84 in. |
| March | 20.2 °F | 38.3 °F | 1.52 in. |
| April | 33.6 °F | 54.7 °F | 2.68 in. |
| May | 46.6 °F | 68.0 °F | 3.77 in. |
| June | 57.6 °F | 77.7 °F | 4.95 in. |
| July | 61.4 °F | 81.7 °F | 3.72 in. |
| August | 58.6 °F | 79.4 °F | 3.99 in. |
| September | 50.0 °F | 72.5 °F | 3.17 in. |
| October | 36.9 °F | 57.8 °F | 2.35 in. |
| November | 23.8 °F | 40.8 °F | 1.34 in. |
| December | 11.2 °F | 26.8 °F | 1.0 in. |
| Annual | 34.2 °F | 53.8 °F | 30.07 in. |
| 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 : -25°F to -20°F |
| Plant Hardiness Zone - 2012 | Zone 4b : -25°F to -20°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |