| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 10°F | 28°F | 20°F | 1.3" |
| February | 8°F | 29°F | 19°F | 0.7" |
| March | 16°F | 40°F | 28°F | 1.5" |
| April | 29°F | 54°F | 41°F | 2.5" |
| May | 39°F | 68°F | 54°F | 2.8" |
| June | 49°F | 77°F | 63°F | 3.4" |
| July | 53°F | 81°F | 68°F | 2.6" |
| August | 53°F | 79°F | 66°F | 3.3" |
| September | 46°F | 72°F | 59°F | 3.5" |
| October | 37°F | 58°F | 48°F | 4.7" |
| November | 28°F | 46°F | 37°F | 2.7" |
| December | 18°F | 32°F | 26°F | 1.9" |
| Index | Ironton | Michigan | National |
| Air quality index | 36 | 69 | 42 |
| Pollution index | 1,397,210 | 4,161,606 | 2,726,193 |
| Measurement | Total |
| Days measured | 247 |
| Days with good air quality | 232 |
| Days with moderate air quality | 15 |
| Days w/ poor A.Q. for sensitive groups | 0 |
| Days with unhealthy air quality | 0 |
| Pollutant | Total |
| Arsenic | 0.001% |
| Benzene | 0.010% |
| Carbon Tetrachloride | 0.003% |
| Lead | 0.000% |
| Mercury | 0.000% |
| City | Population | Air Quality Index | National Avg. |
| Boyne Falls, MI | 350 | 36 | 28.0% |
| Ellsworth, MI | 347 | 36 | 28.0% |
| Charlevoix, MI | 2,544 | 36 | 28.0% |
| Walloon Lake, MI | 318 | 36 | 28.0% |
| Central Lake, MI | 1,020 | 36 | 28.0% |
| Ironton, MI | 116 | 36 | 28.0% |
| City | Population | Air Quality Index | National Avg. |
| Guinda, CA | 116 | 31 | 38.0% |
| Mulat, FL | 116 | 41 | 18.0% |
| Goodell, IA | 116 | 15 | 70.0% |
| Truesdale, IA | 116 | 35 | 30.0% |
| Jordan Hill, LA | 116 | 30 | 40.0% |
| Ironton, MI | 116 | 36 | 28.0% |