| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 28°F | 47°F | 37°F | 2.7" |
| February | 29°F | 50°F | 38°F | 2.3" |
| March | 37°F | 60°F | 47°F | 3.2" |
| April | 47°F | 71°F | 58°F | 3.4" |
| May | 56°F | 78°F | 67°F | 4.6" |
| June | 67°F | 87°F | 77°F | 5.3" |
| July | 72°F | 91°F | 81°F | 4.2" |
| August | 70°F | 90°F | 79°F | 3.2" |
| September | 63°F | 83°F | 72°F | 3.5" |
| October | 52°F | 72°F | 61°F | 5.0" |
| November | 40°F | 61°F | 50°F | 2.5" |
| December | 33°F | 52°F | 42°F | 3.8" |
| Index | Forest Heights | Maryland | National |
| Air quality index | 47 | 43 | 42 |
| Pollution index | 2,776,590 | 5,342,367 | 2,726,193 |
| Measurement | Total |
| Days measured | 365 |
| Days with good air quality | 209 |
| Days with moderate air quality | 145 |
| Days w/ poor A.Q. for sensitive groups | 10 |
| Days with unhealthy air quality | 1 |
| Pollutant | Total |
| Arsenic | 0.070% |
| Benzene | 0.020% |
| Carbon Tetrachloride | 0.010% |
| Lead | 0.020% |
| Mercury | 0.030% |
| City | Population | Air Quality Index | National Avg. |
| Friendship Heights Village, MD | 4,577 | 47 | 6.0% |
| Somerset, MD | 952 | 47 | 6.0% |
| District Heights, MD | 5,996 | 47 | 6.0% |
| Washington, DC | 701,974 | 47 | 6.0% |
| Cottage City, MD | 1,150 | 47 | 6.0% |
| Forest Heights, MD | 2,739 | 47 | 6.0% |
| City | Population | Air Quality Index | National Avg. |
| Wolf Point, MT | 2,739 | 34 | 32.0% |
| South Congaree, SC | 2,739 | 43 | 14.0% |
| Arcadia, LA | 2,738 | 35 | 30.0% |
| Osseo, MN | 2,738 | 46 | 8.0% |
| Casselton, ND | 2,738 | 33 | 34.0% |
| Forest Heights, MD | 2,739 | 47 | 6.0% |
Here are the best places to live in Maryland
These are the largest cities in Maryland
Check out the 10 most dangerous cities in Maryland
Most Dangerous States In The US