| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 27°F | 42°F | 34°F | 3.7" |
| February | 22°F | 39°F | 30°F | 2.4" |
| March | 31°F | 51°F | 40°F | 6.5" |
| April | 41°F | 64°F | 52°F | 5.9" |
| May | 50°F | 74°F | 62°F | 3.6" |
| June | 62°F | 84°F | 73°F | 4.8" |
| July | 65°F | 87°F | 76°F | 6.4" |
| August | 66°F | 86°F | 75°F | 8.4" |
| September | 58°F | 81°F | 70°F | 3.6" |
| October | 50°F | 69°F | 59°F | 5.5" |
| November | 36°F | 55°F | 45°F | 4.8" |
| December | 26°F | 40°F | 33°F | 5.1" |
| Index | Chewsville | Maryland | National |
| Air quality index | 40 | 43 | 42 |
| Pollution index | 16,230,700 | 5,342,367 | 2,726,193 |
| Measurement | Total |
| Days measured | 362 |
| Days with good air quality | 306 |
| Days with moderate air quality | 54 |
| Days w/ poor A.Q. for sensitive groups | 2 |
| Days with unhealthy air quality | 0 |
| Pollutant | Total |
| Arsenic | 0.010% |
| Benzene | 0.130% |
| Carbon Tetrachloride | 0.090% |
| Lead | 0.080% |
| Mercury | 0.020% |
| City | Population | Air Quality Index | National Avg. |
| Mont Alto, PA | 1,756 | 36 | 28.0% |
| Marion, PA | 1,551 | 36 | 28.0% |
| Mercersburg, PA | 1,673 | 36 | 28.0% |
| Middletown, MD | 4,694 | 40 | 20.0% |
| Charlton, MD | 380 | 40 | 20.0% |
| Chewsville, MD | 301 | 40 | 20.0% |
| City | Population | Air Quality Index | National Avg. |
| Los Berros, CA | 301 | 46 | 8.0% |
| Munson, FL | 301 | 41 | 18.0% |
| Worthington Springs, FL | 301 | 35 | 30.0% |
| Pitts, GA | 301 | 39 | 22.0% |
| Blue Mound, KS | 301 | 22 | 56.0% |
| Chewsville, MD | 301 | 40 | 20.0% |
Here are the best places to live in Maryland
Most Dangerous States In The US
See the best places to live in Chewsville
These are the 10 cheapest cities in Maryland