Girdletree, Maryland has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 9.2 °C (low) to 19.8 °C (high). Annual precipitation averages 1188 Millimeters. Girdletree 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 | -1.8 °C | 8.3 °C | 89.41 mm |
| February | -1.2 °C | 9.5 °C | 77.72 mm |
| March | 2.3 °C | 13.3 °C | 105.66 mm |
| April | 7.3 °C | 19.2 °C | 85.09 mm |
| May | 12.5 °C | 23.8 °C | 91.95 mm |
| June | 17.7 °C | 28.4 °C | 96.27 mm |
| July | 20.6 °C | 30.9 °C | 111 mm |
| August | 19.7 °C | 29.8 °C | 118.87 mm |
| September | 16.8 °C | 26.9 °C | 122.17 mm |
| October | 10.6 °C | 21.4 °C | 107.95 mm |
| November | 4.8 °C | 15.4 °C | 80.77 mm |
| December | 0.7 °C | 10.7 °C | 101.09 mm |
| Annual | 9.2 °C | 19.8 °C | 1187.95 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 7b : -15°C to -12.2°C |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |