Swansboro, North Carolina has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 12.6 °C (low) to 22 °C (high). Annual precipitation averages 1531.4 Millimeters. Swansboro is located in USDA Plant Hardiness Zone 8b. The growing season typically runs from the last frost around Mar. 11 - Mar. 20 through the first frost around Nov. 11 - Nov. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 2.2 °C | 12.7 °C | 106.68 mm |
| February | 2.9 °C | 13.8 °C | 103.38 mm |
| March | 6.1 °C | 17.3 °C | 97.54 mm |
| April | 11.2 °C | 21.3 °C | 92.46 mm |
| May | 16.3 °C | 25.3 °C | 109.98 mm |
| June | 20.7 °C | 28.7 °C | 137.67 mm |
| July | 23.1 °C | 30.3 °C | 188.98 mm |
| August | 22.2 °C | 29.8 °C | 189.74 mm |
| September | 19.5 °C | 27.8 °C | 176.78 mm |
| October | 13.9 °C | 23.7 °C | 123.95 mm |
| November | 8.2 °C | 18.6 °C | 102.62 mm |
| December | 4.5 °C | 14.6 °C | 101.6 mm |
| Annual | 12.6 °C | 22 °C | 1531.38 mm |
| Average First Frost Date | Nov. 11 - Nov. 20 |
| Average Last Frost Date | Mar. 11 - Mar. 20 |
| Average Days With Frost | 30-40 Days |
| Plant Hardiness Zone | Zone 8b : -9.4°C to -6.7°C |
| Plant Hardiness Zone - 2012 | Zone 8a : -12.2°C to -9.4°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |