Port Wing, Wisconsin has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 0.2 °C (low) to 10.2 °C (high). Annual precipitation averages 763.3 Millimeters. Port Wing 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 Sep. 21 - Sep. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -14.4 °C | -5.4 °C | 27.18 mm |
| February | -13.3 °C | -2.9 °C | 27.69 mm |
| March | -7.7 °C | 2.4 °C | 42.42 mm |
| April | -1.3 °C | 8.6 °C | 72.64 mm |
| May | 4 °C | 15.8 °C | 80.26 mm |
| June | 9.1 °C | 20.9 °C | 93.22 mm |
| July | 13.4 °C | 25.1 °C | 98.04 mm |
| August | 13.3 °C | 24.4 °C | 81.28 mm |
| September | 9.3 °C | 19.8 °C | 79.25 mm |
| October | 3.1 °C | 12.2 °C | 71.12 mm |
| November | -3.3 °C | 4.1 °C | 48.51 mm |
| December | -10.1 °C | -2.6 °C | 41.66 mm |
| Annual | 0.2 °C | 10.2 °C | 763.27 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 5a : -28.9°C to -26.1°C |
| Plant Hardiness Zone - 2012 | Zone 4b : -31.7°C to -28.9°C |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |