| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 11°F | 30°F | 21°F | 2.0" |
| February | 11°F | 31°F | 21°F | 1.4" |
| March | 18°F | 41°F | 29°F | 1.8" |
| April | 30°F | 55°F | 42°F | 3.5" |
| May | 40°F | 69°F | 54°F | 2.8" |
| June | 50°F | 78°F | 64°F | 3.7" |
| July | 55°F | 83°F | 69°F | 3.3" |
| August | 54°F | 81°F | 67°F | 3.5" |
| September | 47°F | 74°F | 60°F | 3.2" |
| October | 38°F | 60°F | 48°F | 3.4" |
| November | 28°F | 47°F | 37°F | 2.0" |
| December | 18°F | 34°F | 26°F | 2.1" |
| Index | Hillman | Michigan | National |
| Air quality index | 36 | 69 | 42 |
| Pollution index | 1,346,710 | 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 | 0.001% |
| Lead | 0.001% |
| Mercury | 0.001% |
| City | Population | Air Quality Index | National Avg. |
| Posen, MI | 212 | 32 | 36.0% |
| Atlanta, MI | 647 | 36 | 28.0% |
| Hillman, MI | 610 | 36 | 28.0% |
| City | Population | Air Quality Index | National Avg. |
| Grand Tower, IL | 610 | 43 | 14.0% |
| Beechmont, KY | 610 | 43 | 14.0% |
| Hampton, MN | 610 | 37 | 26.0% |
| Chippewa Park, OH | 610 | 39 | 22.0% |
| Jeromesville, OH | 610 | 41 | 18.0% |
| Hillman, MI | 610 | 36 | 28.0% |