Shell Lake, Wisconsin has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Annual precipitation averages 825.8 Millimeters. Shell Lake is located in USDA Plant Hardiness Zone 4b. The growing season typically runs from the last frost around May 11 - May 20 through the first frost around Sep. 21 - Sep. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -16.2 °C | -5.8 °C | 22.1 mm |
| February | -14.7 °C | -2.8 °C | 23.11 mm |
| March | -7.8 °C | 4.2 °C | 39.37 mm |
| April | -0.5 °C | 12 °C | 72.64 mm |
| May | 6.3 °C | 19.2 °C | 98.81 mm |
| June | 11.7 °C | 24.3 °C | 109.98 mm |
| July | 14 °C | 26.7 °C | 108.71 mm |
| August | 12.8 °C | 25.6 °C | 103.63 mm |
| September | 8.6 °C | 20.7 °C | 92.46 mm |
| October | 2.3 °C | 13.3 °C | 80.77 mm |
| November | -4.6 °C | 4.4 °C | 42.93 mm |
| December | -11.7 °C | -2.9 °C | 31.24 mm |
| Annual | 0 °C | 11.6 °C | 825.75 mm |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| Average Last Frost Date | May 11 - May 20 |
| 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 | Abnormally Dry |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |