| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 18°F | 32°F | 25°F | 4.1" |
| February | 16°F | 31°F | 23°F | 3.2" |
| March | 29°F | 48°F | 38°F | 3.7" |
| April | 38°F | 62°F | 49°F | 5.9" |
| May | 49°F | 74°F | 61°F | 4.0" |
| June | 60°F | 84°F | 72°F | 4.6" |
| July | 60°F | 85°F | 73°F | 9.3" |
| August | 62°F | 83°F | 72°F | 8.2" |
| September | 54°F | 81°F | 67°F | 2.4" |
| October | 45°F | 68°F | 55°F | 5.0" |
| November | 30°F | 49°F | 39°F | 3.4" |
| December | 16°F | 31°F | 23°F | 2.7" |
| Index | Aurora | Illinois | National |
| Air quality index | 55 | 41 | 42 |
| Pollution index | 1,874,490 | 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 | 0.002% |
| Benzene | 0.030% |
| Carbon Tetrachloride | 0.010% |
| Lead | 0.010% |
| Mercury | 0.010% |
| City | Population | Air Quality Index | National Avg. |
| Kaneville, IL | 518 | 0 | 100.0% |
| Oswego, IL | 35,470 | 0 | 100.0% |
| Sugar Grove, IL | 9,756 | 0 | 100.0% |
| Plano, IL | 11,058 | 0 | 100.0% |
| Millbrook, IL | 357 | 0 | 100.0% |
| Aurora, IL | 199,326 | 55 | 10.0% |
| City | Population | Air Quality Index | National Avg. |
| Glendale, CA | 199,357 | 72 | 44.0% |
| Grand Rapids, MI | 199,417 | 38 | 24.0% |
| Amarillo, TX | 199,225 | 44 | 12.0% |
| Montgomery, AL | 199,054 | 52 | 4.0% |
| Huntington Beach, CA | 199,778 | 72 | 44.0% |
| Aurora, IL | 199,326 | 55 | 10.0% |
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