Bloomington, Wisconsin has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 37.5 °F (low) to 56.4 °F (high). Annual precipitation averages 38 Inches. Bloomington 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 | 9.9 °F | 26.3 °F | 1.24 in. |
| February | 13.4 °F | 30.9 °F | 1.25 in. |
| March | 25.1 °F | 43.5 °F | 1.99 in. |
| April | 36.5 °F | 57.2 °F | 3.86 in. |
| May | 48.2 °F | 68.9 °F | 4.52 in. |
| June | 58.4 °F | 78.2 °F | 5.83 in. |
| July | 62.3 °F | 81.7 °F | 4.75 in. |
| August | 60.2 °F | 79.9 °F | 3.99 in. |
| September | 51.8 °F | 73.1 °F | 3.92 in. |
| October | 39.8 °F | 60.0 °F | 2.87 in. |
| November | 27.9 °F | 44.7 °F | 2.18 in. |
| December | 17.0 °F | 32.0 °F | 1.61 in. |
| Annual | 37.5 °F | 56.4 °F | 38.01 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 |