Ellicott City, Maryland has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 46.1 °F (low) to 66.3 °F (high). Annual precipitation averages 48.1 Inches. Ellicott City is located in USDA Plant Hardiness Zone 7b. The growing season typically runs from the last frost around Apr. 11 - Apr. 20 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 25.8 °F | 43.2 °F | 3.37 in. |
| February | 27.2 °F | 46.0 °F | 3.0 in. |
| March | 34.0 °F | 54.3 °F | 4.3 in. |
| April | 43.9 °F | 66.4 °F | 3.72 in. |
| May | 53.6 °F | 75.4 °F | 4.5 in. |
| June | 62.7 °F | 83.8 °F | 4.48 in. |
| July | 67.5 °F | 88.1 °F | 4.55 in. |
| August | 65.7 °F | 86.2 °F | 3.94 in. |
| September | 58.9 °F | 79.6 °F | 4.76 in. |
| October | 47.0 °F | 68.1 °F | 4.16 in. |
| November | 37.2 °F | 56.9 °F | 3.36 in. |
| December | 30.1 °F | 47.2 °F | 3.96 in. |
| Annual | 46.1 °F | 66.3 °F | 48.1 in. |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 75-100 Days |
| Plant Hardiness Zone | Zone 7b : 5°F to 10°F |
| Plant Hardiness Zone - 2012 | Zone 7a : 0°F to 5°F |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |