| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 20°F | 34°F | 26°F | 1.9" |
| February | 21°F | 36°F | 28°F | 1.6" |
| March | 33°F | 49°F | 40°F | 2.4" |
| April | 42°F | 62°F | 51°F | 3.6" |
| May | 52°F | 73°F | 61°F | 4.3" |
| June | 63°F | 82°F | 72°F | 4.6" |
| July | 68°F | 86°F | 76°F | 3.5" |
| August | 67°F | 83°F | 75°F | 5.1" |
| September | 60°F | 77°F | 68°F | 2.8" |
| October | 48°F | 65°F | 55°F | 3.9" |
| November | 36°F | 51°F | 43°F | 2.2" |
| December | 25°F | 37°F | 31°F | 2.2" |
| Index | La Grange | Illinois | National |
| Air quality index | 55 | 41 | 42 |
| Pollution index | 14,981,300 | 3,148,694 | 2,726,193 |
| Measurement | Total |
| Days measured | 365 |
| Days with good air quality | 121 |
| Days with moderate air quality | 227 |
| Days w/ poor A.Q. for sensitive groups | 16 |
| Days with unhealthy air quality | 1 |
| Pollutant | Total |
| Arsenic | 0.010% |
| Benzene | 0.140% |
| Carbon Tetrachloride | 0.030% |
| Lead | 0.020% |
| Mercury | 0.010% |
| City | Population | Air Quality Index | National Avg. |
| Hickory Hills, IL | 14,253 | 55 | 10.0% |
| Oak Forest, IL | 27,403 | 55 | 10.0% |
| Robbins, IL | 5,068 | 55 | 10.0% |
| Evergreen Park, IL | 19,290 | 55 | 10.0% |
| Harwood Heights, IL | 8,393 | 55 | 10.0% |
| La Grange, IL | 15,555 | 55 | 10.0% |
| City | Population | Air Quality Index | National Avg. |
| Hot Springs Village, AR | 15,562 | 38 | 24.0% |
| Mebane, NC | 15,564 | 31 | 38.0% |
| Dixon, IL | 15,544 | 42 | 16.0% |
| Frankfort, IN | 15,569 | 42 | 16.0% |
| Dentsville, SC | 15,537 | 43 | 14.0% |
| La Grange, IL | 15,555 | 55 | 10.0% |
Here are the best places to live in Illinois
See the best places to live in La Grange
Safest States In The US
Check out the 10 most dangerous cities in Illinois