Sauk City, Wisconsin has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 2.6 °C (low) to 13.9 °C (high). Annual precipitation averages 922.5 Millimeters. Sauk City is located in USDA Plant Hardiness Zone 5a. The growing season typically runs from the last frost around May 11 - May 20 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -12.4 °C | -2.6 °C | 33.27 mm |
| February | -11.1 °C | -0.2 °C | 33.27 mm |
| March | -4.8 °C | 6.4 °C | 50.8 mm |
| April | 1.7 °C | 14 °C | 95.76 mm |
| May | 8.3 °C | 20.8 °C | 107.19 mm |
| June | 14.3 °C | 26.2 °C | 139.19 mm |
| July | 16.3 °C | 28.2 °C | 111.51 mm |
| August | 14.9 °C | 27.1 °C | 105.66 mm |
| September | 10.4 °C | 23.1 °C | 87.38 mm |
| October | 3.9 °C | 16 °C | 68.58 mm |
| November | -2.4 °C | 7.4 °C | 51.31 mm |
| December | -8.4 °C | 0.5 °C | 38.61 mm |
| Annual | 2.6 °C | 13.9 °C | 922.53 mm |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 11 - May 20 |
| 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 | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |