Glenmont, Maryland has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 46 °F (low) to 65.3 °F (high). Annual precipitation averages 45.5 Inches. Glenmont 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 | 25.5 °F | 42.3 °F | 3.12 in. |
| February | 26.9 °F | 45.4 °F | 2.76 in. |
| March | 33.8 °F | 53.9 °F | 4.0 in. |
| April | 44.0 °F | 66.2 °F | 3.47 in. |
| May | 54.0 °F | 74.3 °F | 4.44 in. |
| June | 62.6 °F | 82.6 °F | 4.56 in. |
| July | 67.3 °F | 86.8 °F | 4.37 in. |
| August | 65.7 °F | 84.8 °F | 3.7 in. |
| September | 59.0 °F | 78.1 °F | 4.41 in. |
| October | 47.0 °F | 66.7 °F | 3.84 in. |
| November | 36.7 °F | 56.1 °F | 3.16 in. |
| December | 29.9 °F | 46.3 °F | 3.71 in. |
| Annual | 46 °F | 65.3 °F | 45.54 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 |