| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 18°F | 33°F | 25°F | 2.0" |
| February | 18°F | 34°F | 26°F | 1.2" |
| March | 27°F | 47°F | 37°F | 2.0" |
| April | 38°F | 61°F | 49°F | 3.1" |
| May | 49°F | 72°F | 60°F | 3.6" |
| June | 59°F | 81°F | 70°F | 3.9" |
| July | 62°F | 84°F | 73°F | 4.7" |
| August | 61°F | 82°F | 71°F | 3.4" |
| September | 54°F | 75°F | 64°F | 3.4" |
| October | 43°F | 63°F | 52°F | 3.9" |
| November | 32°F | 50°F | 41°F | 2.2" |
| December | 23°F | 37°F | 30°F | 1.6" |
| Index | Athens | Michigan | National |
| Air quality index | 38 | 69 | 42 |
| Pollution index | 1,872,410 | 4,161,606 | 2,726,193 |
| Measurement | Total |
| Days measured | 362 |
| Days with good air quality | 312 |
| Days with moderate air quality | 50 |
| Days w/ poor A.Q. for sensitive groups | 0 |
| Days with unhealthy air quality | 0 |
| Pollutant | Total |
| Arsenic | 0.002% |
| Benzene | 0.030% |
| Carbon Tetrachloride | 0.002% |
| Lead | 0.010% |
| Mercury | 0.000% |
| City | Population | Air Quality Index | National Avg. |
| Marshall, MI | 7,136 | 38 | 24.0% |
| Burlington, MI | 307 | 38 | 24.0% |
| Mendon, MI | 855 | 38 | 24.0% |
| Tekonsha, MI | 647 | 38 | 24.0% |
| Centreville, MI | 1,197 | 38 | 24.0% |
| Athens, MI | 1,080 | 38 | 24.0% |
| City | Population | Air Quality Index | National Avg. |
| Argenta, IL | 1,080 | 44 | 12.0% |
| Carson City, MI | 1,080 | 36 | 28.0% |
| Absarokee, MT | 1,080 | 21 | 58.0% |
| McAdenville, NC | 1,080 | 49 | 2.0% |
| Marathon, NY | 1,080 | 34 | 32.0% |
| Athens, MI | 1,080 | 38 | 24.0% |