| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 27°F | 41°F | 35°F | 2.2" |
| February | 28°F | 45°F | 37°F | 1.4" |
| March | 36°F | 54°F | 45°F | 4.8" |
| April | 46°F | 65°F | 56°F | 1.6" |
| May | 55°F | 73°F | 65°F | 8.1" |
| June | 64°F | 82°F | 75°F | 3.0" |
| July | 70°F | 87°F | 80°F | 0.5" |
| August | 67°F | 84°F | 76°F | 1.1" |
| September | 61°F | 78°F | 70°F | 1.7" |
| October | 50°F | 68°F | 59°F | 7.1" |
| November | 39°F | 57°F | 48°F | 2.9" |
| December | 33°F | 47°F | 40°F | 4.4" |
| Index | Butlertown | Maryland | National |
| Air quality index | 46 | 43 | 42 |
| Pollution index | 9,823,920 | 5,342,367 | 2,726,193 |
| Measurement | Total |
| Days measured | 365 |
| Days with good air quality | 223 |
| Days with moderate air quality | 129 |
| Days w/ poor A.Q. for sensitive groups | 13 |
| Days with unhealthy air quality | 0 |
| Pollutant | Total |
| Arsenic | 0.010% |
| Benzene | 0.070% |
| Carbon Tetrachloride | 0.050% |
| Lead | 0.030% |
| Mercury | 0.140% |
| City | Population | Air Quality Index | National Avg. |
| Millington, MD | 634 | 42 | 16.0% |
| Barclay, MD | 247 | 42 | 16.0% |
| Cecilton, MD | 925 | 42 | 16.0% |
| Church Hill, MD | 891 | 42 | 16.0% |
| Kennedyville, MD | 439 | 42 | 16.0% |
| Butlertown, MD | 335 | 46 | 8.0% |
| City | Population | Air Quality Index | National Avg. |
| Anchor Bay, CA | 335 | 33 | 34.0% |
| Las Flores CDP (Tehama County), CA | 335 | 89 | 78.0% |
| Lake Angelus, MI | 335 | 56 | 12.0% |
| Coleman, OK | 335 | 325 | 550.0% |
| Eau Claire, PA | 335 | 31 | 38.0% |
| Butlertown, MD | 335 | 46 | 8.0% |