South Bethany, Delaware has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 49.6 °F (low) to 63.8 °F (high). Annual precipitation averages 48.4 Inches. South Bethany is located in USDA Plant Hardiness Zone 8a. 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 | 29.6 °F | 44.0 °F | 3.69 in. |
| February | 30.5 °F | 45.4 °F | 3.11 in. |
| March | 36.9 °F | 50.7 °F | 4.4 in. |
| April | 46.0 °F | 61.0 °F | 3.57 in. |
| May | 55.2 °F | 69.2 °F | 3.75 in. |
| June | 64.7 °F | 78.5 °F | 3.8 in. |
| July | 70.3 °F | 83.7 °F | 4.49 in. |
| August | 69.5 °F | 82.3 °F | 4.86 in. |
| September | 64.2 °F | 77.1 °F | 4.24 in. |
| October | 52.6 °F | 67.9 °F | 4.64 in. |
| November | 41.7 °F | 57.2 °F | 3.55 in. |
| December | 34.2 °F | 49.0 °F | 4.3 in. |
| Annual | 49.6 °F | 63.8 °F | 48.4 in. |
| Average First Frost Date | Nov. 1 - Nov. 10 |
| Average Last Frost Date | Apr. 1 - Apr. 10 |
| Average Days With Frost | 50-75 Days |
| Plant Hardiness Zone | Zone 8a : 10°F to 15°F |
| Plant Hardiness Zone - 2012 | Zone 7b : 5°F to 10°F |
| Current Drought Conditions | Extreme Drought |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |