Rocky Hill, New Jersey has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 43.4 °F (low) to 63.8 °F (high). Annual precipitation averages 49.4 Inches. Rocky Hill is located in USDA Plant Hardiness Zone 7a. The growing season typically runs from the last frost around Apr. 11 - Apr. 20 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 22.6 °F | 39.9 °F | 3.6 in. |
| February | 23.9 °F | 42.5 °F | 2.81 in. |
| March | 31.0 °F | 50.6 °F | 4.4 in. |
| April | 40.9 °F | 62.9 °F | 3.94 in. |
| May | 50.5 °F | 72.6 °F | 4.08 in. |
| June | 59.6 °F | 81.6 °F | 4.59 in. |
| July | 65.4 °F | 86.5 °F | 5.07 in. |
| August | 63.6 °F | 84.5 °F | 4.55 in. |
| September | 56.3 °F | 78.0 °F | 4.23 in. |
| October | 44.8 °F | 66.0 °F | 4.16 in. |
| November | 34.4 °F | 55.1 °F | 3.48 in. |
| December | 27.6 °F | 44.9 °F | 4.52 in. |
| Annual | 43.4 °F | 63.8 °F | 49.43 in. |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 100-125 Days |
| Plant Hardiness Zone | Zone 7a : 0°F to 5°F |
| Plant Hardiness Zone - 2012 | Zone 6b : -5°F to 0°F |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |