| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 19°F | 38°F | 27°F | 1.2" |
| February | 22°F | 41°F | 30°F | 1.2" |
| March | 34°F | 55°F | 43°F | 1.6" |
| April | 44°F | 67°F | 55°F | 3.9" |
| May | 54°F | 76°F | 64°F | 4.5" |
| June | 64°F | 85°F | 74°F | 5.6" |
| July | 67°F | 88°F | 77°F | 3.9" |
| August | 65°F | 86°F | 75°F | 3.8" |
| September | 57°F | 80°F | 68°F | 3.0" |
| October | 46°F | 69°F | 57°F | 2.8" |
| November | 34°F | 54°F | 44°F | 2.1" |
| December | 25°F | 41°F | 32°F | 1.9" |
| Index | Augusta | Illinois | National |
| Air quality index | 41 | 41 | 42 |
| Pollution index | 3,988,710 | 3,148,694 | 2,726,193 |
| Measurement | Total |
| Days measured | 241 |
| Days with good air quality | 208 |
| Days with moderate air quality | 33 |
| Days w/ poor A.Q. for sensitive groups | 0 |
| Days with unhealthy air quality | 0 |
| Pollutant | Total |
| Arsenic | 0.010% |
| Benzene | 0.050% |
| Carbon Tetrachloride | 0.010% |
| Lead | 0.030% |
| Mercury | 0.010% |
| City | Population | Air Quality Index | National Avg. |
| Basco, IL | 85 | 29 | 42.0% |
| Plymouth, IL | 441 | 29 | 42.0% |
| Carthage, IL | 2,474 | 29 | 42.0% |
| Colchester, IL | 1,347 | 29 | 42.0% |
| Tennessee, IL | 88 | 29 | 42.0% |
| Augusta, IL | 605 | 41 | 18.0% |
| City | Population | Air Quality Index | National Avg. |
| Collins, GA | 605 | 39 | 22.0% |
| Portal, GA | 605 | 47 | 6.0% |
| Keystone, IA | 605 | 39 | 22.0% |
| Maple Hill, KS | 605 | 41 | 18.0% |
| Boothville, LA | 605 | 45 | 10.0% |
| Augusta, IL | 605 | 41 | 18.0% |
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