| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 15°F | 31°F | 23°F | 1.3" |
| February | 16°F | 32°F | 24°F | 1.2" |
| March | 28°F | 45°F | 36°F | 2.4" |
| April | 37°F | 58°F | 46°F | 3.9" |
| May | 47°F | 70°F | 58°F | 3.3" |
| June | 57°F | 79°F | 67°F | 3.7" |
| July | 61°F | 83°F | 72°F | 4.6" |
| August | 60°F | 81°F | 70°F | 4.0" |
| September | 53°F | 74°F | 63°F | 3.0" |
| October | 43°F | 62°F | 52°F | 3.1" |
| November | 32°F | 49°F | 40°F | 1.8" |
| December | 21°F | 36°F | 28°F | 1.8" |
| Index | Lake Catherine | Illinois | National |
| Air quality index | 39 | 41 | 42 |
| Pollution index | 4,811,660 | 3,148,694 | 2,726,193 |
| Measurement | Total |
| Days measured | 203 |
| Days with good air quality | 174 |
| Days with moderate air quality | 28 |
| Days w/ poor A.Q. for sensitive groups | 1 |
| Days with unhealthy air quality | 0 |
| Pollutant | Total |
| Arsenic | 0.004% |
| Benzene | 0.080% |
| Carbon Tetrachloride | 0.010% |
| Lead | 0.040% |
| Mercury | 0.010% |
| City | Population | Air Quality Index | National Avg. |
| Bloomfield, WI | 4,725 | 37 | 26.0% |
| Lake Ivanhoe, WI | 398 | 37 | 26.0% |
| Greenwood, IL | 352 | 37 | 26.0% |
| Springfield, WI | 131 | 37 | 26.0% |
| Gages Lake, IL | 9,939 | 39 | 22.0% |
| Lake Catherine, IL | 1,289 | 39 | 22.0% |
| City | Population | Air Quality Index | National Avg. |
| Russiaville, IN | 1,289 | 42 | 16.0% |
| Bowling Green, MD | 1,289 | 36 | 28.0% |
| Buckeystown, MD | 1,289 | 40 | 20.0% |
| Tyler, MN | 1,289 | 32 | 36.0% |
| Barker Heights, NC | 1,289 | 44 | 12.0% |
| Lake Catherine, IL | 1,289 | 39 | 22.0% |
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