| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 15°F | 36°F | 24°F | 1.5" |
| February | 15°F | 35°F | 24°F | 2.3" |
| March | 30°F | 51°F | 39°F | 3.5" |
| April | 41°F | 65°F | 52°F | 8.7" |
| May | 52°F | 74°F | 62°F | 7.1" |
| June | 62°F | 83°F | 72°F | 5.9" |
| July | 66°F | 87°F | 76°F | 7.3" |
| August | 63°F | 84°F | 72°F | 7.4" |
| September | 54°F | 77°F | 64°F | 10.8" |
| October | 43°F | 66°F | 53°F | 4.9" |
| November | 30°F | 50°F | 39°F | 4.4" |
| December | 22°F | 39°F | 30°F | 4.0" |
| Index | Chariton | Iowa | National |
| Air quality index | 39 | 39 | 42 |
| Pollution index | 376,148 | 1,154,535 | 2,726,193 |
| Measurement | Total |
| Days measured | 365 |
| Days with good air quality | 306 |
| Days with moderate air quality | 59 |
| 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 | 0.001% |
| Mercury | 0.000% |
| City | Population | Air Quality Index | National Avg. |
| Millerton, IA | 125 | 39 | 22.0% |
| Woodburn, IA | 119 | 39 | 22.0% |
| Williamson, IA | 184 | 39 | 22.0% |
| Derby, IA | 113 | 39 | 22.0% |
| Lacona, IA | 339 | 39 | 22.0% |
| Chariton, IA | 4,127 | 39 | 22.0% |
| City | Population | Air Quality Index | National Avg. |
| West Milwaukee, WI | 4,128 | 44 | 12.0% |
| Butler, MO | 4,125 | 47 | 6.0% |
| Sharpsville, PA | 4,125 | 42 | 16.0% |
| Justin, TX | 4,125 | 51 | 2.0% |
| Madawaska Valley, ON | 4,125 | n/a | |
| Chariton, IA | 4,127 | 39 | 22.0% |
Here are the best places to live in Iowa
10 Best cities in Iowa for employment
These are the 10 most affordable cities in Iowa
10 best cities to buy a new house in Iowa