North Haven, Connecticut has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 42.2 °F (low) to 61 °F (high). Annual precipitation averages 51.3 Inches. North Haven is located in USDA Plant Hardiness Zone 6b. The growing season typically runs from the last frost around Apr. 1 - Apr. 10 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 20.5 °F | 37.1 °F | 3.82 in. |
| February | 21.8 °F | 39.3 °F | 3.34 in. |
| March | 29.3 °F | 46.9 °F | 4.44 in. |
| April | 39.3 °F | 59.1 °F | 4.41 in. |
| May | 49.2 °F | 69.7 °F | 4.06 in. |
| June | 58.7 °F | 78.4 °F | 4.6 in. |
| July | 64.5 °F | 84.2 °F | 4.03 in. |
| August | 63.0 °F | 82.4 °F | 4.15 in. |
| September | 55.7 °F | 76.1 °F | 4.54 in. |
| October | 43.9 °F | 64.2 °F | 5.27 in. |
| November | 34.1 °F | 52.4 °F | 3.95 in. |
| December | 26.2 °F | 42.4 °F | 4.67 in. |
| Annual | 42.2 °F | 61 °F | 51.28 in. |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 1 - Apr. 10 |
| Average Days With Frost | 75-100 Days |
| Plant Hardiness Zone | Zone 6b : -5°F to 0°F |
| Plant Hardiness Zone - 2012 | Zone 6b : -5°F to 0°F |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |