Perry Hall, Maryland has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 46.9 °F (low) to 65.8 °F (high). Annual precipitation averages 49.3 Inches. Perry Hall 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 | 26.0 °F | 42.6 °F | 3.45 in. |
| February | 27.3 °F | 45.4 °F | 2.89 in. |
| March | 34.1 °F | 53.6 °F | 4.38 in. |
| April | 44.7 °F | 65.6 °F | 3.73 in. |
| May | 54.3 °F | 74.7 °F | 4.3 in. |
| June | 63.7 °F | 83.4 °F | 4.57 in. |
| July | 68.8 °F | 87.8 °F | 4.54 in. |
| August | 66.9 °F | 85.9 °F | 4.29 in. |
| September | 60.3 °F | 79.5 °F | 4.88 in. |
| October | 48.5 °F | 68.0 °F | 4.61 in. |
| November | 37.8 °F | 56.6 °F | 3.42 in. |
| December | 30.5 °F | 46.8 °F | 4.19 in. |
| Annual | 46.9 °F | 65.8 °F | 49.25 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 7a : 0°F to 5°F |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |