Sewell, New Jersey has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 46.8 °F (low) to 64.6 °F (high). Annual precipitation averages 47.3 Inches. Sewell is located in USDA Plant Hardiness Zone 7b. The growing season typically runs from the last frost around Apr. 1 - Apr. 10 through the first frost around Nov. 1 - Nov. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 25.9 °F | 41.3 °F | 3.74 in. |
| February | 27.2 °F | 43.8 °F | 2.83 in. |
| March | 33.8 °F | 51.6 °F | 4.5 in. |
| April | 44.1 °F | 63.9 °F | 3.56 in. |
| May | 53.6 °F | 73.6 °F | 3.75 in. |
| June | 63.1 °F | 82.8 °F | 4.31 in. |
| July | 68.7 °F | 86.9 °F | 4.66 in. |
| August | 67.2 °F | 84.9 °F | 4.58 in. |
| September | 60.5 °F | 78.4 °F | 4.12 in. |
| October | 48.3 °F | 66.5 °F | 3.97 in. |
| November | 38.1 °F | 55.8 °F | 3.08 in. |
| December | 31.1 °F | 46.2 °F | 4.24 in. |
| Annual | 46.8 °F | 64.6 °F | 47.34 in. |
| Average First Frost Date | Nov. 1 - Nov. 10 |
| Average Last Frost Date | Apr. 1 - Apr. 10 |
| Average Days With Frost | 75-100 Days |
| Plant Hardiness Zone | Zone 7b : 5°F to 10°F |
| Plant Hardiness Zone - 2012 | Zone 7a : 0°F to 5°F |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |