Cass City, Michigan has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 37 °F (low) to 56.1 °F (high). Annual precipitation averages 32.9 Inches. Cass City 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 | 14.8 °F | 29.1 °F | 1.97 in. |
| February | 14.7 °F | 31.6 °F | 1.62 in. |
| March | 23.0 °F | 41.3 °F | 1.87 in. |
| April | 33.4 °F | 54.7 °F | 3.38 in. |
| May | 44.7 °F | 66.9 °F | 3.52 in. |
| June | 54.6 °F | 77.2 °F | 3.48 in. |
| July | 58.7 °F | 80.9 °F | 3.15 in. |
| August | 57.6 °F | 79.0 °F | 3.31 in. |
| September | 50.2 °F | 72.9 °F | 3.08 in. |
| October | 40.1 °F | 59.6 °F | 3.01 in. |
| November | 30.6 °F | 45.8 °F | 2.49 in. |
| December | 22.0 °F | 34.5 °F | 2.02 in. |
| Annual | 37 °F | 56.1 °F | 32.9 in. |
| 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 : -10°F to -5°F |
| Plant Hardiness Zone - 2012 | Zone 5b : -15°F to -10°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |