Ellerslie, Maryland has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 6 °C (low) to 18.4 °C (high). Annual precipitation averages 1011.7 Millimeters. Ellerslie is located in USDA Plant Hardiness Zone 7a. 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 | -4.7 °C | 4.6 °C | 65.02 mm |
| February | -3.9 °C | 6.7 °C | 64.52 mm |
| March | -0.3 °C | 11.5 °C | 89.66 mm |
| April | 4.8 °C | 19.3 °C | 88.65 mm |
| May | 10 °C | 24.2 °C | 113.79 mm |
| June | 14.9 °C | 28.3 °C | 106.93 mm |
| July | 17.2 °C | 30.8 °C | 87.12 mm |
| August | 16.3 °C | 29.9 °C | 82.04 mm |
| September | 12.6 °C | 26.3 °C | 90.42 mm |
| October | 6.2 °C | 19.7 °C | 75.44 mm |
| November | 0.9 °C | 12.6 °C | 69.6 mm |
| December | -2.4 °C | 6.8 °C | 78.49 mm |
| Annual | 6 °C | 18.4 °C | 1011.68 mm |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 100-125 Days |
| Plant Hardiness Zone | Zone 7a : -17.8°C to -15°C |
| Plant Hardiness Zone - 2012 | Zone 7a : -17.8°C to -15°C |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |