Swedesboro, New Jersey has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 8.4 °C (low) to 17.8 °C (high). Annual precipitation averages 1184.7 Millimeters. Swedesboro 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 | -3.2 °C | 4.9 °C | 91.69 mm |
| February | -2.5 °C | 6.2 °C | 74.93 mm |
| March | 1.1 °C | 10.4 °C | 111 mm |
| April | 6.9 °C | 17.2 °C | 90.68 mm |
| May | 12.3 °C | 22.5 °C | 93.73 mm |
| June | 17.6 °C | 27.7 °C | 109.98 mm |
| July | 20.7 °C | 30 °C | 118.36 mm |
| August | 19.8 °C | 29.1 °C | 113.79 mm |
| September | 16 °C | 25.6 °C | 102.87 mm |
| October | 9.2 °C | 19.1 °C | 97.54 mm |
| November | 3.6 °C | 13.1 °C | 75.95 mm |
| December | -0.4 °C | 7.7 °C | 104.14 mm |
| Annual | 8.4 °C | 17.8 °C | 1184.66 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 |