Hawthorne, New Jersey has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 6.6 °C (low) to 17.1 °C (high). Annual precipitation averages 1249.2 Millimeters. Hawthorne is located in USDA Plant Hardiness Zone 7a. 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 | -5.4 °C | 3.7 °C | 90.68 mm |
| February | -4.5 °C | 5.2 °C | 69.85 mm |
| March | -0.5 °C | 9.7 °C | 108.46 mm |
| April | 5.3 °C | 16.6 °C | 102.62 mm |
| May | 10.7 °C | 22.2 °C | 101.6 mm |
| June | 16 °C | 27.2 °C | 123.7 mm |
| July | 18.9 °C | 29.9 °C | 111.51 mm |
| August | 17.9 °C | 28.8 °C | 116.33 mm |
| September | 13.7 °C | 25.1 °C | 110.49 mm |
| October | 7.1 °C | 18.5 °C | 111 mm |
| November | 1.9 °C | 12.2 °C | 94.23 mm |
| December | -2.1 °C | 6.5 °C | 108.71 mm |
| Annual | 6.6 °C | 17.1 °C | 1249.18 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 7a : -17.8°C to -15°C |
| Plant Hardiness Zone - 2012 | Zone 6b : -20.6°C to -17.8°C |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |