Horicon, Wisconsin has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 2.6 °C (low) to 13.1 °C (high). Annual precipitation averages 875.3 Millimeters. Horicon 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 | -12 °C | -3.2 °C | 35.05 mm |
| February | -10.7 °C | -1.2 °C | 34.04 mm |
| March | -4.7 °C | 5.5 °C | 46.74 mm |
| April | 1.8 °C | 12.9 °C | 89.66 mm |
| May | 8.2 °C | 19.8 °C | 96.27 mm |
| June | 13.8 °C | 25.2 °C | 125.48 mm |
| July | 16.1 °C | 27.3 °C | 105.41 mm |
| August | 14.9 °C | 26.3 °C | 94.23 mm |
| September | 10.5 °C | 22.7 °C | 84.58 mm |
| October | 4.1 °C | 15.2 °C | 74.17 mm |
| November | -2.1 °C | 7.1 °C | 49.78 mm |
| December | -8.2 °C | -0.1 °C | 39.88 mm |
| Annual | 2.6 °C | 13.1 °C | 875.29 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 5a : -28.9°C to -26.1°C |
| Plant Hardiness Zone - 2012 | Zone 5a : -28.9°C to -26.1°C |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |