Port Deposit, Maryland has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 7 °C (low) to 18.4 °C (high). Annual precipitation averages 1216.1 Millimeters. Port Deposit 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 Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -4.6 °C | 5.3 °C | 88.14 mm |
| February | -4.1 °C | 6.7 °C | 70.61 mm |
| March | -0.1 °C | 11.4 °C | 108.97 mm |
| April | 5.7 °C | 18.2 °C | 96.52 mm |
| May | 11.1 °C | 23.5 °C | 95.25 mm |
| June | 16.3 °C | 28.2 °C | 114.55 mm |
| July | 19.1 °C | 30.7 °C | 114.3 mm |
| August | 18.2 °C | 29.8 °C | 109.47 mm |
| September | 14.3 °C | 26.2 °C | 114.55 mm |
| October | 7.6 °C | 19.8 °C | 109.98 mm |
| November | 2.1 °C | 13.2 °C | 84.07 mm |
| December | -1.8 °C | 7.6 °C | 109.73 mm |
| Annual | 7 °C | 18.4 °C | 1216.14 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 7b : -15°C to -12.2°C |
| Plant Hardiness Zone - 2012 | Zone 7a : -17.8°C to -15°C |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |