Harrisonville, New Jersey has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 8 °C (low) to 17.9 °C (high). Annual precipitation averages 1192.5 Millimeters. Harrisonville 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 | -3.6 °C | 5.1 °C | 92.96 mm |
| February | -2.8 °C | 6.3 °C | 76.71 mm |
| March | 0.8 °C | 10.7 °C | 112.27 mm |
| April | 6.6 °C | 17.4 °C | 90.93 mm |
| May | 11.9 °C | 22.7 °C | 93.47 mm |
| June | 17.2 °C | 27.8 °C | 109.47 mm |
| July | 20.3 °C | 30.1 °C | 119.38 mm |
| August | 19.3 °C | 29.1 °C | 115.32 mm |
| September | 15.5 °C | 25.8 °C | 100.84 mm |
| October | 8.8 °C | 19.2 °C | 99.06 mm |
| November | 3.3 °C | 13.1 °C | 76.45 mm |
| December | -0.8 °C | 7.8 °C | 105.66 mm |
| Annual | 8 °C | 17.9 °C | 1192.52 mm |
| 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 : -15°C to -12.2°C |
| Plant Hardiness Zone - 2012 | Zone 7a : -17.8°C to -15°C |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |