Wilmington, Delaware has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 7.9 °C (low) to 17.5 °C (high). Annual precipitation averages 1214.6 Millimeters. Wilmington 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 | -3.8 °C | 4.6 °C | 89.66 mm |
| February | -3.2 °C | 5.9 °C | 73.91 mm |
| March | 0.7 °C | 10.3 °C | 111.25 mm |
| April | 6.6 °C | 17 °C | 97.54 mm |
| May | 11.9 °C | 22.2 °C | 96.77 mm |
| June | 17.1 °C | 27.3 °C | 117.6 mm |
| July | 20.2 °C | 29.8 °C | 122.43 mm |
| August | 19.2 °C | 28.8 °C | 110.24 mm |
| September | 15.3 °C | 25.3 °C | 111 mm |
| October | 8.6 °C | 18.8 °C | 97.54 mm |
| November | 2.9 °C | 12.7 °C | 78.49 mm |
| December | -1 °C | 7.3 °C | 108.2 mm |
| Annual | 7.9 °C | 17.5 °C | 1214.63 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 | Moderate Drought |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |