Marion, Wisconsin has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 34.3 °F (low) to 54.5 °F (high). Annual precipitation averages 33.1 Inches. Marion is located in USDA Plant Hardiness Zone 5a. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 7.8 °F | 24.9 °F | 1.25 in. |
| February | 9.4 °F | 28.8 °F | 1.1 in. |
| March | 20.3 °F | 40.4 °F | 1.79 in. |
| April | 32.5 °F | 54.4 °F | 3.08 in. |
| May | 44.7 °F | 67.2 °F | 3.81 in. |
| June | 54.7 °F | 76.7 °F | 4.49 in. |
| July | 58.8 °F | 81.0 °F | 3.88 in. |
| August | 56.8 °F | 79.0 °F | 3.7 in. |
| September | 48.5 °F | 71.3 °F | 3.59 in. |
| October | 36.8 °F | 57.7 °F | 2.93 in. |
| November | 26.1 °F | 43.1 °F | 1.89 in. |
| December | 14.7 °F | 30.0 °F | 1.61 in. |
| Annual | 34.3 °F | 54.5 °F | 33.12 in. |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 5a : -20°F to -15°F |
| Plant Hardiness Zone - 2012 | Zone 4b : -25°F to -20°F |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |