| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 24°F | 42°F | 32°F | 3.4" |
| February | 25°F | 44°F | 33°F | 2.6" |
| March | 34°F | 56°F | 44°F | 3.9" |
| April | 43°F | 69°F | 56°F | 4.2" |
| May | 52°F | 76°F | 63°F | 4.1" |
| June | 60°F | 83°F | 71°F | 4.9" |
| July | 64°F | 85°F | 74°F | 4.8" |
| August | 63°F | 86°F | 73°F | 3.6" |
| September | 56°F | 80°F | 67°F | 3.2" |
| October | 45°F | 68°F | 55°F | 3.7" |
| November | 35°F | 57°F | 45°F | 2.9" |
| December | 29°F | 46°F | 37°F | 4.2" |
| Index | Middlebourne | West Virginia | National |
| Air quality index | 31 | 126 | 42 |
| Pollution index | 505,265 | 1,996,538 | 2,726,193 |
| Measurement | Total |
| Days measured | 111 |
| Days with good air quality | 101 |
| Days with moderate air quality | 10 |
| Days w/ poor A.Q. for sensitive groups | 0 |
| Days with unhealthy air quality | 0 |
| Pollutant | Total |
| Arsenic | 0.003% |
| Benzene | 0.010% |
| Carbon Tetrachloride | 0.001% |
| Lead | 0.002% |
| Mercury | 0.010% |
| City | Population | Air Quality Index | National Avg. |
| Pine Grove, WV | 379 | 31 | 38.0% |
| Reader, WV | 298 | 31 | 38.0% |
| West Union, WV | 1,058 | 31 | 38.0% |
| Jacksonburg, WV | 82 | 31 | 38.0% |
| Pennsboro, WV | 1,511 | 35 | 30.0% |
| Middlebourne, WV | 743 | 31 | 38.0% |
| City | Population | Air Quality Index | National Avg. |
| Butler, KY | 743 | 54 | 8.0% |
| Fox Chase, KY | 743 | 49 | 2.0% |
| Loretto, KY | 743 | 39 | 22.0% |
| Potomac Park, MD | 743 | 36 | 28.0% |
| Lake View, SC | 743 | 30 | 40.0% |
| Middlebourne, WV | 743 | 31 | 38.0% |