Deer Park, Wisconsin has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 0.7 °C (low) to 11.7 °C (high). Annual precipitation averages 851.4 Millimeters. Deer Park is located in USDA Plant Hardiness Zone 4b. 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 | -15.7 °C | -5.7 °C | 24.38 mm |
| February | -14.1 °C | -2.8 °C | 23.88 mm |
| March | -7.1 °C | 4.1 °C | 41.91 mm |
| April | 0.2 °C | 12 °C | 75.44 mm |
| May | 7.2 °C | 19.2 °C | 100.58 mm |
| June | 12.9 °C | 24.4 °C | 123.95 mm |
| July | 15.2 °C | 26.8 °C | 112.27 mm |
| August | 13.9 °C | 25.8 °C | 107.95 mm |
| September | 9.4 °C | 21.5 °C | 87.88 mm |
| October | 2.5 °C | 13.5 °C | 74.68 mm |
| November | -4.2 °C | 4.8 °C | 44.7 mm |
| December | -11.4 °C | -2.8 °C | 33.78 mm |
| Annual | 0.7 °C | 11.7 °C | 851.4 mm |
| 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 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 |