Birchwood, Wisconsin has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 31.1 °F (low) to 52.5 °F (high). Annual precipitation averages 34.7 Inches. Birchwood is located in USDA Plant Hardiness Zone 4a. The growing season typically runs from the last frost around May 21 - May 31 through the first frost around Sep.1 - Sep. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 2.1 °F | 21.5 °F | 1.05 in. |
| February | 4.6 °F | 26.8 °F | 1.09 in. |
| March | 17.0 °F | 39.0 °F | 1.72 in. |
| April | 30.1 °F | 53.0 °F | 3.07 in. |
| May | 42.1 °F | 66.4 °F | 4.06 in. |
| June | 52.2 °F | 75.4 °F | 4.62 in. |
| July | 56.5 °F | 79.4 °F | 4.35 in. |
| August | 54.1 °F | 77.3 °F | 4.11 in. |
| September | 46.5 °F | 69.4 °F | 3.85 in. |
| October | 34.8 °F | 55.4 °F | 3.39 in. |
| November | 22.9 °F | 39.7 °F | 1.93 in. |
| December | 10.3 °F | 26.8 °F | 1.43 in. |
| Annual | 31.1 °F | 52.5 °F | 34.67 in. |
| Average First Frost Date | Sep.1 - Sep. 10 |
| Average Last Frost Date | May 21 - May 31 |
| Average Days With Frost | Over 180 Days |
| Plant Hardiness Zone | Zone 4a : -30°F to -25°F |
| Plant Hardiness Zone - 2012 | Zone 3b : -35°F to -30°F |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |