Rio Grande, New Jersey has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 48.9 °F (low) to 63.3 °F (high). Annual precipitation averages 44.8 Inches. Rio Grande is located in USDA Plant Hardiness Zone 8a. 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 | 28.6 °F | 43.1 °F | 3.27 in. |
| February | 29.4 °F | 44.3 °F | 2.89 in. |
| March | 35.9 °F | 50.8 °F | 4.42 in. |
| April | 45.6 °F | 59.7 °F | 3.53 in. |
| May | 54.6 °F | 68.9 °F | 3.56 in. |
| June | 64.4 °F | 78.1 °F | 3.5 in. |
| July | 69.8 °F | 83.9 °F | 4.17 in. |
| August | 68.6 °F | 82.4 °F | 3.97 in. |
| September | 62.7 °F | 77.2 °F | 3.65 in. |
| October | 51.8 °F | 66.5 °F | 4.34 in. |
| November | 41.3 °F | 56.4 °F | 3.31 in. |
| December | 33.5 °F | 47.9 °F | 4.2 in. |
| Annual | 48.9 °F | 63.3 °F | 44.81 in. |
| Average First Frost Date | Nov. 1 - Nov. 10 |
| Average Last Frost Date | Apr. 1 - Apr. 10 |
| Average Days With Frost | 50-75 Days |
| Plant Hardiness Zone | Zone 8a : 10°F to 15°F |
| Plant Hardiness Zone - 2012 | Zone 7b : 5°F to 10°F |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |