Viroqua, Wisconsin has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 2.2 °C (low) to 12.4 °C (high). Annual precipitation averages 957.3 Millimeters. Viroqua 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 Sep. 21 - Sep. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -13.2 °C | -4.4 °C | 27.18 mm |
| February | -11.1 °C | -1.8 °C | 27.18 mm |
| March | -4.9 °C | 5.1 °C | 50.04 mm |
| April | 1.6 °C | 12.9 °C | 100.58 mm |
| May | 8.2 °C | 19.5 °C | 122.68 mm |
| June | 13.8 °C | 24.6 °C | 147.83 mm |
| July | 16 °C | 26.7 °C | 114.3 mm |
| August | 14.8 °C | 25.6 °C | 115.32 mm |
| September | 10.1 °C | 21.6 °C | 93.47 mm |
| October | 3.7 °C | 14.4 °C | 68.58 mm |
| November | -3.1 °C | 5.7 °C | 50.29 mm |
| December | -9.2 °C | -1.3 °C | 39.88 mm |
| Annual | 2.2 °C | 12.4 °C | 957.33 mm |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| 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 4b : -31.7°C to -28.9°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |