Gilman, Wisconsin has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from -0.2 °C (low) to 11.6 °C (high). Annual precipitation averages 829.6 Millimeters. Gilman is located in USDA Plant Hardiness Zone 4a. 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 | -16.3 °C | -5.6 °C | 26.92 mm |
| February | -15 °C | -2.8 °C | 24.89 mm |
| March | -8.1 °C | 4.1 °C | 40.39 mm |
| April | -0.6 °C | 12 °C | 73.66 mm |
| May | 6.2 °C | 19.2 °C | 96.01 mm |
| June | 11.7 °C | 24.2 °C | 118.87 mm |
| July | 13.9 °C | 26.5 °C | 95.5 mm |
| August | 12.5 °C | 25.3 °C | 104.65 mm |
| September | 8.1 °C | 21 °C | 92.2 mm |
| October | 1.7 °C | 13.4 °C | 75.69 mm |
| November | -4.7 °C | 4.6 °C | 46.74 mm |
| December | -11.7 °C | -2.6 °C | 34.04 mm |
| Annual | -0.2 °C | 11.6 °C | 829.56 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 4a : -34.4°C to -31.7°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 |