Crownsville, Maryland has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 46.5 °F (low) to 66 °F (high). Annual precipitation averages 46.6 Inches. Crownsville 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 | 25.8 °F | 43.3 °F | 3.16 in. |
| February | 27.2 °F | 46.1 °F | 2.79 in. |
| March | 34.1 °F | 54.1 °F | 4.18 in. |
| April | 44.3 °F | 65.9 °F | 3.48 in. |
| May | 54.0 °F | 74.5 °F | 4.27 in. |
| June | 63.3 °F | 83.1 °F | 4.49 in. |
| July | 68.1 °F | 87.5 °F | 4.6 in. |
| August | 66.5 °F | 85.8 °F | 3.97 in. |
| September | 59.8 °F | 79.3 °F | 4.68 in. |
| October | 47.7 °F | 67.9 °F | 3.97 in. |
| November | 37.3 °F | 56.9 °F | 3.16 in. |
| December | 30.2 °F | 47.4 °F | 3.81 in. |
| Annual | 46.5 °F | 66 °F | 46.56 in. |
| 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 : 5°F to 10°F |
| Plant Hardiness Zone - 2012 | Zone 7b : 5°F to 10°F |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |