| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 12°F | 26°F | 18°F | 0.5" |
| February | 13°F | 29°F | 20°F | 0.6" |
| March | 29°F | 44°F | 35°F | 1.4" |
| April | 40°F | 60°F | 48°F | 3.0" |
| May | 50°F | 71°F | 60°F | 3.0" |
| June | 60°F | 80°F | 69°F | 6.0" |
| July | 63°F | 82°F | 72°F | 4.7" |
| August | 61°F | 80°F | 70°F | 4.2" |
| September | 53°F | 75°F | 63°F | 5.0" |
| October | 42°F | 61°F | 50°F | 2.3" |
| November | 30°F | 46°F | 37°F | 1.1" |
| December | 16°F | 30°F | 23°F | 1.4" |
| Index | Charles City | Iowa | National |
| Air quality index | 15 | 39 | 42 |
| Pollution index | 1,013,960 | 1,154,535 | 2,726,193 |
| Measurement | Total |
| Days measured | 118 |
| Days with good air quality | 118 |
| Days with moderate air quality | 0 |
| 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. |
| Marble Rock, IA | 322 | 15 | 70.0% |
| Alta Vista, IA | 223 | 15 | 70.0% |
| Bassett, IA | 42 | 15 | 70.0% |
| Orchard, IA | 63 | 15 | 70.0% |
| Rockford, IA | 827 | 15 | 70.0% |
| Charles City, IA | 7,351 | 15 | 70.0% |
| City | Population | Air Quality Index | National Avg. |
| Globe, AZ | 7,351 | 60 | 20.0% |
| Sandwich, IL | 7,351 | 0 | 100.0% |
| Iron Mountain, MI | 7,352 | 36 | 28.0% |
| Hudsonville, MI | 7,353 | 38 | 24.0% |
| Tuttle, OK | 7,348 | 48 | 4.0% |
| Charles City, IA | 7,351 | 15 | 70.0% |
Here are the best places to live in Iowa
Most Dangerous Cities In The US
See the best places to live in Charles City
Check out the 10 most dangerous cities in Iowa