New Haven, Vermont has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 35.1 °F (low) to 55.4 °F (high). Annual precipitation averages 38.8 Inches. New Haven is located in USDA Plant Hardiness Zone 5a. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 9.8 °F | 28.2 °F | 2.58 in. |
| February | 10.8 °F | 31.0 °F | 1.86 in. |
| March | 20.3 °F | 39.8 °F | 2.27 in. |
| April | 32.4 °F | 54.0 °F | 3.08 in. |
| May | 44.3 °F | 67.2 °F | 3.57 in. |
| June | 53.6 °F | 75.7 °F | 3.9 in. |
| July | 58.8 °F | 80.7 °F | 4.67 in. |
| August | 57.0 °F | 78.9 °F | 4.03 in. |
| September | 49.2 °F | 71.5 °F | 3.22 in. |
| October | 38.2 °F | 58.0 °F | 3.77 in. |
| November | 28.8 °F | 45.7 °F | 2.96 in. |
| December | 17.8 °F | 34.1 °F | 2.85 in. |
| Annual | 35.1 °F | 55.4 °F | 38.76 in. |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 150-180 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 | Dfb - Humid Continental Mild Summer, Wet All Year |