Rahway, New Jersey has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 7.7 °C (low) to 17.9 °C (high). Annual precipitation averages 1227.1 Millimeters. Rahway 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 Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -4.1 °C | 4.7 °C | 88.9 mm |
| February | -3.3 °C | 6.2 °C | 72.14 mm |
| March | 0.4 °C | 10.7 °C | 105.41 mm |
| April | 6.1 °C | 17.4 °C | 98.3 mm |
| May | 11.4 °C | 22.8 °C | 100.58 mm |
| June | 16.7 °C | 27.8 °C | 115.82 mm |
| July | 19.8 °C | 30.6 °C | 126.49 mm |
| August | 18.9 °C | 29.5 °C | 114.3 mm |
| September | 15.1 °C | 25.8 °C | 106.93 mm |
| October | 8.6 °C | 19.2 °C | 109.47 mm |
| November | 3.2 °C | 13.1 °C | 85.09 mm |
| December | -0.9 °C | 7.4 °C | 103.63 mm |
| Annual | 7.7 °C | 17.9 °C | 1227.06 mm |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| 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 6b : -20.6°C to -17.8°C |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |