Accident, Maryland has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 3.7 °C (low) to 14.4 °C (high). Annual precipitation averages 1329.2 Millimeters. Accident is located in USDA Plant Hardiness Zone 6a. The growing season typically runs from the last frost around May 11 - May 20 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -7.6 °C | 1.3 °C | 112.27 mm |
| February | -6.6 °C | 3.3 °C | 103.89 mm |
| March | -3 °C | 7.9 °C | 118.62 mm |
| April | 2.6 °C | 15.1 °C | 113.54 mm |
| May | 8.2 °C | 20 °C | 128.52 mm |
| June | 12.8 °C | 23.9 °C | 132.59 mm |
| July | 14.9 °C | 25.9 °C | 124.46 mm |
| August | 14.2 °C | 25.3 °C | 107.7 mm |
| September | 10.4 °C | 22.1 °C | 99.82 mm |
| October | 4.5 °C | 15.7 °C | 88.14 mm |
| November | -0.8 °C | 9.1 °C | 88.65 mm |
| December | -4.9 °C | 3.7 °C | 111 mm |
| Annual | 3.7 °C | 14.4 °C | 1329.2 mm |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 11 - May 20 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 6a : -23.3°C to -20.6°C |
| Plant Hardiness Zone - 2012 | Zone 6a : -23.3°C to -20.6°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |