Fairmount, Maryland has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 50.2 °F (low) to 67.3 °F (high). Annual precipitation averages 45.3 Inches. Fairmount 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 Nov. 1 - Nov. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 29.9 °F | 46.3 °F | 3.25 in. |
| February | 30.9 °F | 48.6 °F | 2.93 in. |
| March | 37.3 °F | 55.4 °F | 4.1 in. |
| April | 47.1 °F | 66.3 °F | 3.41 in. |
| May | 56.9 °F | 74.8 °F | 3.56 in. |
| June | 66.3 °F | 83.0 °F | 3.97 in. |
| July | 71.2 °F | 87.4 °F | 4.37 in. |
| August | 69.6 °F | 85.6 °F | 4.76 in. |
| September | 63.9 °F | 80.3 °F | 4.29 in. |
| October | 52.6 °F | 70.2 °F | 4.0 in. |
| November | 41.8 °F | 59.1 °F | 3.05 in. |
| December | 34.6 °F | 50.7 °F | 3.58 in. |
| Annual | 50.2 °F | 67.3 °F | 45.27 in. |
| Average First Frost Date | Nov. 1 - Nov. 10 |
| Average Last Frost Date | Apr. 1 - Apr. 10 |
| Average Days With Frost | 50-75 Days |
| Plant Hardiness Zone | Zone 8a : 10°F to 15°F |
| Plant Hardiness Zone - 2012 | Zone 7b : 5°F to 10°F |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |