New Haven, Indiana has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 4.7 °C (low) to 15.7 °C (high). Annual precipitation averages 971.8 Millimeters. New Haven is located in USDA Plant Hardiness Zone 6a. 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 | -8.1 °C | 0.2 °C | 62.99 mm |
| February | -7.1 °C | 2.2 °C | 52.07 mm |
| March | -2.3 °C | 8.3 °C | 64.01 mm |
| April | 3.4 °C | 15.8 °C | 95 mm |
| May | 9.8 °C | 22.1 °C | 113.79 mm |
| June | 15.4 °C | 27.1 °C | 104.39 mm |
| July | 17.1 °C | 29.2 °C | 99.31 mm |
| August | 15.9 °C | 28 °C | 98.55 mm |
| September | 11.7 °C | 24.8 °C | 76.2 mm |
| October | 5.7 °C | 17.8 °C | 72.14 mm |
| November | 0 °C | 9.7 °C | 74.42 mm |
| December | -4.9 °C | 3 °C | 58.93 mm |
| Annual | 4.7 °C | 15.7 °C | 971.8 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 100-125 Days |
| Plant Hardiness Zone | Zone 6a : -23.3°C to -20.6°C |
| Plant Hardiness Zone - 2012 | Zone 6a : -23.3°C to -20.6°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |