Grenloch, New Jersey has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 46.2 °F (low) to 64.8 °F (high). Annual precipitation averages 47.3 Inches. Grenloch 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 | 25.4 °F | 41.6 °F | 3.71 in. |
| February | 26.8 °F | 44.2 °F | 2.82 in. |
| March | 33.4 °F | 51.9 °F | 4.53 in. |
| April | 43.6 °F | 64.1 °F | 3.53 in. |
| May | 52.9 °F | 73.7 °F | 3.78 in. |
| June | 62.5 °F | 82.9 °F | 4.27 in. |
| July | 68.0 °F | 87.2 °F | 4.65 in. |
| August | 66.2 °F | 85.2 °F | 4.64 in. |
| September | 59.7 °F | 78.5 °F | 4.1 in. |
| October | 47.5 °F | 66.5 °F | 3.92 in. |
| November | 37.4 °F | 55.9 °F | 3.1 in. |
| December | 30.5 °F | 46.3 °F | 4.22 in. |
| Annual | 46.2 °F | 64.8 °F | 47.27 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 6b : -5°F to 0°F |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |