Tunnel City, Wisconsin has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 34.9 °F (low) to 55 °F (high). Annual precipitation averages 36.5 Inches. Tunnel City 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 Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 7.4 °F | 24.7 °F | 1.19 in. |
| February | 10.3 °F | 29.6 °F | 1.12 in. |
| March | 21.7 °F | 41.6 °F | 1.87 in. |
| April | 34.0 °F | 55.8 °F | 3.7 in. |
| May | 45.9 °F | 68.0 °F | 4.55 in. |
| June | 55.8 °F | 77.1 °F | 5.37 in. |
| July | 59.6 °F | 81.2 °F | 4.28 in. |
| August | 57.3 °F | 79.0 °F | 4.43 in. |
| September | 49.2 °F | 71.6 °F | 3.78 in. |
| October | 37.5 °F | 58.3 °F | 2.8 in. |
| November | 25.9 °F | 42.8 °F | 1.87 in. |
| December | 14.6 °F | 30.0 °F | 1.51 in. |
| Annual | 34.9 °F | 55 °F | 36.47 in. |
| 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 4b : -25°F to -20°F |
| Plant Hardiness Zone - 2012 | Zone 4b : -25°F to -20°F |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |