Summit, New Jersey has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 5.8 °C (low) to 17 °C (high). Annual precipitation averages 1251.2 Millimeters. Summit 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. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -5.9 °C | 3.6 °C | 92.46 mm |
| February | -5.2 °C | 5.1 °C | 72.64 mm |
| March | -1.3 °C | 9.7 °C | 107.95 mm |
| April | 4.6 °C | 16.4 °C | 102.36 mm |
| May | 9.8 °C | 21.9 °C | 104.14 mm |
| June | 15.1 °C | 26.9 °C | 118.62 mm |
| July | 17.9 °C | 29.7 °C | 116.84 mm |
| August | 17 °C | 28.7 °C | 115.06 mm |
| September | 13.1 °C | 24.9 °C | 111.25 mm |
| October | 6.4 °C | 18.2 °C | 112.52 mm |
| November | 1.2 °C | 12 °C | 89.41 mm |
| December | -2.8 °C | 6.4 °C | 107.95 mm |
| Annual | 5.8 °C | 17 °C | 1251.2 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 100-125 Days |
| Plant Hardiness Zone | Zone 7a : -17.8°C to -15°C |
| Plant Hardiness Zone - 2012 | Zone 6a : -23.3°C to -20.6°C |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |