White Marsh, Maryland has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 9 °C (low) to 18.6 °C (high). Annual precipitation averages 1243.8 Millimeters. White Marsh 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 Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -2.6 °C | 5.8 °C | 87.12 mm |
| February | -1.9 °C | 7.1 °C | 72.14 mm |
| March | 1.9 °C | 11.6 °C | 111.25 mm |
| April | 7.8 °C | 18.3 °C | 94.23 mm |
| May | 13.1 °C | 23.4 °C | 108.71 mm |
| June | 18.3 °C | 28.3 °C | 116.59 mm |
| July | 21.2 °C | 30.8 °C | 115.06 mm |
| August | 20.2 °C | 29.9 °C | 107.95 mm |
| September | 16.4 °C | 26.3 °C | 123.7 mm |
| October | 9.8 °C | 19.8 °C | 115.57 mm |
| November | 3.9 °C | 13.6 °C | 85.85 mm |
| December | -0.1 °C | 8.2 °C | 105.66 mm |
| Annual | 9 °C | 18.6 °C | 1243.83 mm |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 1 - Apr. 10 |
| Average Days With Frost | 75-100 Days |
| Plant Hardiness Zone | Zone 8a : -12.2°C to -9.4°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 |