| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 22°F | 34°F | 27°F | 2.4" |
| February | 24°F | 39°F | 31°F | 2.3" |
| March | 32°F | 50°F | 40°F | 3.7" |
| April | 37°F | 58°F | 46°F | 3.8" |
| May | 47°F | 71°F | 58°F | 4.6" |
| June | 55°F | 79°F | 67°F | 8.5" |
| July | 60°F | 84°F | 72°F | 5.6" |
| August | 58°F | 81°F | 69°F | 7.7" |
| September | 51°F | 76°F | 63°F | 3.9" |
| October | 42°F | 62°F | 51°F | 3.6" |
| November | 31°F | 52°F | 41°F | 2.7" |
| December | 26°F | 39°F | 32°F | 1.8" |
| Index | Fostoria | Michigan | National |
| Air quality index | 38 | 69 | 42 |
| Pollution index | 449,908 | 4,161,606 | 2,726,193 |
| Measurement | Total |
| Days measured | 340 |
| Days with good air quality | 282 |
| Days with moderate air quality | 58 |
| Days w/ poor A.Q. for sensitive groups | 0 |
| Days with unhealthy air quality | 0 |
| Pollutant | Total |
| Arsenic | 0.000% |
| Benzene | 0.010% |
| Carbon Tetrachloride | 0.001% |
| Lead | 0.010% |
| Mercury | 0.000% |
| City | Population | Air Quality Index | National Avg. |
| Vassar, MI | 2,650 | 26 | 48.0% |
| Columbiaville, MI | 790 | 38 | 24.0% |
| Marlette, MI | 2,049 | 38 | 24.0% |
| Otter Lake, MI | 368 | 38 | 24.0% |
| Otisville, MI | 971 | 38 | 24.0% |
| Fostoria, MI | 780 | 38 | 24.0% |
| City | Population | Air Quality Index | National Avg. |
| Independence, CA | 780 | 47 | 6.0% |
| Duck Key, FL | 780 | 41 | 18.0% |
| Chevy Chase Section Five, MD | 780 | 47 | 6.0% |
| Dover, MN | 780 | 36 | 28.0% |
| Roper, NC | 780 | 0 | 100.0% |
| Fostoria, MI | 780 | 38 | 24.0% |