Mardela Springs, Maryland has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 8.4 °C (low) to 19.9 °C (high). Annual precipitation averages 1151.6 Millimeters. Mardela Springs is located in USDA Plant Hardiness Zone 7b. The growing season typically runs from the last frost around Apr. 11 - Apr. 20 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -2.5 °C | 7.7 °C | 83.82 mm |
| February | -2.1 °C | 9.1 °C | 73.91 mm |
| March | 1.5 °C | 13.2 °C | 102.11 mm |
| April | 7.1 °C | 19.6 °C | 89.15 mm |
| May | 12.3 °C | 24.3 °C | 94.74 mm |
| June | 17.4 °C | 29 °C | 110.74 mm |
| July | 20.2 °C | 31.4 °C | 105.66 mm |
| August | 18.9 °C | 30.2 °C | 118.87 mm |
| September | 15.6 °C | 27.2 °C | 103.63 mm |
| October | 9.2 °C | 21.3 °C | 93.98 mm |
| November | 3.3 °C | 15.1 °C | 79.76 mm |
| December | -0.3 °C | 10.1 °C | 95.25 mm |
| Annual | 8.4 °C | 19.9 °C | 1151.62 mm |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 75-100 Days |
| Plant Hardiness Zone | Zone 7b : -15°C to -12.2°C |
| Plant Hardiness Zone - 2012 | Zone 7b : -15°C to -12.2°C |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |