Harrison, Wisconsin has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 36.7 °F (low) to 54.6 °F (high). Annual precipitation averages 33 Inches. Harrison is located in USDA Plant Hardiness Zone 5b. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 10.4 °F | 25.3 °F | 1.37 in. |
| February | 12.5 °F | 28.8 °F | 1.13 in. |
| March | 22.8 °F | 40.3 °F | 1.86 in. |
| April | 34.6 °F | 53.8 °F | 3.21 in. |
| May | 46.5 °F | 66.7 °F | 3.67 in. |
| June | 56.8 °F | 76.4 °F | 4.61 in. |
| July | 61.1 °F | 80.9 °F | 3.78 in. |
| August | 59.3 °F | 78.9 °F | 3.6 in. |
| September | 51.4 °F | 71.8 °F | 3.23 in. |
| October | 39.5 °F | 58.0 °F | 2.84 in. |
| November | 28.3 °F | 43.7 °F | 1.98 in. |
| December | 17.2 °F | 31.0 °F | 1.71 in. |
| Annual | 36.7 °F | 54.6 °F | 32.99 in. |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 5b : -15°F to -10°F |
| Plant Hardiness Zone - 2012 | Zone 5a : -20°F to -15°F |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |