Winter, Wisconsin has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from -0.9 °C (low) to 11 °C (high). Annual precipitation averages 852.7 Millimeters. Winter is located in USDA Plant Hardiness Zone 4a. The growing season typically runs from the last frost around May 11 - May 20 through the first frost around Sep.11 - Sep. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -17 °C | -5.9 °C | 27.43 mm |
| February | -15.7 °C | -2.9 °C | 25.4 mm |
| March | -9.1 °C | 3.6 °C | 40.64 mm |
| April | -1.6 °C | 11.1 °C | 70.1 mm |
| May | 5.2 °C | 18.6 °C | 97.54 mm |
| June | 10.7 °C | 23.7 °C | 116.59 mm |
| July | 13.2 °C | 25.8 °C | 110.74 mm |
| August | 11.8 °C | 24.7 °C | 92.71 mm |
| September | 7.7 °C | 20.5 °C | 103.89 mm |
| October | 1.3 °C | 12.6 °C | 88.39 mm |
| November | -5.4 °C | 3.8 °C | 44.45 mm |
| December | -12.4 °C | -3.2 °C | 34.8 mm |
| Annual | -0.9 °C | 11 °C | 852.68 mm |
| Average First Frost Date | Sep.11 - Sep. 20 |
| Average Last Frost Date | May 11 - May 20 |
| Average Days With Frost | Over 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 | Moderate Drought |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |