Seabrook Beach, New Hampshire has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 40.2 °F (low) to 58.1 °F (high). Annual precipitation averages 49.8 Inches. Seabrook Beach is located in USDA Plant Hardiness Zone 6b. 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 | 18.9 °F | 34.6 °F | 3.79 in. |
| February | 20.3 °F | 37.1 °F | 3.66 in. |
| March | 26.7 °F | 44.0 °F | 4.68 in. |
| April | 36.1 °F | 55.7 °F | 4.37 in. |
| May | 45.8 °F | 65.5 °F | 4.11 in. |
| June | 55.3 °F | 75.4 °F | 4.43 in. |
| July | 61.5 °F | 81.5 °F | 3.53 in. |
| August | 60.3 °F | 80.3 °F | 3.49 in. |
| September | 54.0 °F | 72.8 °F | 3.96 in. |
| October | 43.7 °F | 60.7 °F | 5.0 in. |
| November | 34.3 °F | 50.0 °F | 3.98 in. |
| December | 25.6 °F | 40.0 °F | 4.77 in. |
| Annual | 40.2 °F | 58.1 °F | 49.77 in. |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 6b : -5°F to 0°F |
| Plant Hardiness Zone - 2012 | Zone 6a : -10°F to -5°F |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |