Howards Grove, Wisconsin has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 2.8 °C (low) to 12.3 °C (high). Annual precipitation averages 836.4 Millimeters. Howards Grove is located in USDA Plant Hardiness Zone 5b. 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 | -10.8 °C | -2.8 °C | 42.67 mm |
| February | -9.7 °C | -1.1 °C | 36.58 mm |
| March | -4.4 °C | 4.2 °C | 49.53 mm |
| April | 1.3 °C | 11 °C | 91.19 mm |
| May | 7.1 °C | 17.5 °C | 96.27 mm |
| June | 12.7 °C | 23.3 °C | 99.06 mm |
| July | 15.8 °C | 26.4 °C | 88.39 mm |
| August | 15.2 °C | 25.4 °C | 87.38 mm |
| September | 10.9 °C | 21.8 °C | 67.82 mm |
| October | 4.6 °C | 14.4 °C | 74.93 mm |
| November | -1.5 °C | 6.9 °C | 54.36 mm |
| December | -7.2 °C | 0.4 °C | 48.26 mm |
| Annual | 2.8 °C | 12.3 °C | 836.44 mm |
| 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 5b : -26.1°C to -23.3°C |
| Plant Hardiness Zone - 2012 | Zone 5b : -26.1°C to -23.3°C |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |