Baltimore, Maryland has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 9 °C (low) to 18.9 °C (high). Annual precipitation averages 1209.3 Millimeters. Baltimore 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 | -2.5 °C | 6.2 °C | 86.11 mm |
| February | -1.7 °C | 7.6 °C | 73.91 mm |
| March | 2 °C | 12.1 °C | 109.73 mm |
| April | 7.8 °C | 18.6 °C | 95 mm |
| May | 13.1 °C | 23.6 °C | 105.16 mm |
| June | 18.3 °C | 28.8 °C | 113.54 mm |
| July | 21.1 °C | 31.2 °C | 108.71 mm |
| August | 20 °C | 30.1 °C | 102.62 mm |
| September | 16.3 °C | 26.4 °C | 118.36 mm |
| October | 9.7 °C | 20.1 °C | 109.73 mm |
| November | 4 °C | 13.9 °C | 84.84 mm |
| December | 0 °C | 8.6 °C | 101.6 mm |
| Annual | 9 °C | 18.9 °C | 1209.31 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 |