New Berlin, Wisconsin has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 2.9 °C (low) to 13.4 °C (high). Annual precipitation averages 926.6 Millimeters. New Berlin 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. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -11.1 °C | -2.2 °C | 44.96 mm |
| February | -9.4 °C | -0.2 °C | 42.42 mm |
| March | -4.3 °C | 5.9 °C | 51.31 mm |
| April | 1.8 °C | 12.7 °C | 99.57 mm |
| May | 7.7 °C | 19.2 °C | 106.17 mm |
| June | 13.1 °C | 24.8 °C | 125.73 mm |
| July | 16 °C | 27.4 °C | 95.25 mm |
| August | 15.2 °C | 26.6 °C | 97.79 mm |
| September | 10.6 °C | 22.7 °C | 83.31 mm |
| October | 4.4 °C | 15.6 °C | 73.15 mm |
| November | -1.7 °C | 7.6 °C | 55.12 mm |
| December | -7.6 °C | 0.8 °C | 51.82 mm |
| Annual | 2.9 °C | 13.4 °C | 926.6 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 5b : -26.1°C to -23.3°C |
| Plant Hardiness Zone - 2012 | Zone 5b : -26.1°C to -23.3°C |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |