New Berlin, Illinois has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 43.3 °F (low) to 63.2 °F (high). Annual precipitation averages 38.9 Inches. New Berlin is located in USDA Plant Hardiness Zone 6a. The growing season typically runs from the last frost around Apr. 11 - Apr. 20 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 19.0 °F | 35.1 °F | 2.07 in. |
| February | 22.5 °F | 40.3 °F | 1.88 in. |
| March | 31.6 °F | 51.7 °F | 2.75 in. |
| April | 42.2 °F | 64.5 °F | 4.11 in. |
| May | 53.8 °F | 74.3 °F | 4.67 in. |
| June | 62.9 °F | 82.8 °F | 4.63 in. |
| July | 66.1 °F | 85.6 °F | 3.82 in. |
| August | 63.9 °F | 84.7 °F | 3.36 in. |
| September | 55.5 °F | 79.6 °F | 3.33 in. |
| October | 44.0 °F | 67.0 °F | 3.12 in. |
| November | 33.3 °F | 52.2 °F | 3.0 in. |
| December | 24.4 °F | 40.3 °F | 2.16 in. |
| Annual | 43.3 °F | 63.2 °F | 38.9 in. |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 100-125 Days |
| Plant Hardiness Zone | Zone 6a : -10°F to -5°F |
| Plant Hardiness Zone - 2012 | Zone 6a : -10°F to -5°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |