Hazel Green, Wisconsin has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 37.4 °F (low) to 56.7 °F (high). Annual precipitation averages 38.5 Inches. Hazel Green is located in USDA Plant Hardiness Zone 5a. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 10.4 °F | 26.7 °F | 1.29 in. |
| February | 13.9 °F | 31.1 °F | 1.54 in. |
| March | 25.1 °F | 43.8 °F | 2.06 in. |
| April | 36.1 °F | 57.4 °F | 3.85 in. |
| May | 47.8 °F | 69.2 °F | 4.45 in. |
| June | 58.2 °F | 78.7 °F | 5.78 in. |
| July | 61.8 °F | 81.7 °F | 4.78 in. |
| August | 59.7 °F | 80.1 °F | 3.97 in. |
| September | 51.4 °F | 73.4 °F | 3.82 in. |
| October | 39.6 °F | 60.5 °F | 2.97 in. |
| November | 28.1 °F | 45.2 °F | 2.2 in. |
| December | 17.1 °F | 32.4 °F | 1.75 in. |
| Annual | 37.4 °F | 56.7 °F | 38.46 in. |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 5a : -20°F to -15°F |
| Plant Hardiness Zone - 2012 | Zone 5a : -20°F to -15°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |