| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 17°F | 34°F | 24°F | 3.4" |
| February | 18°F | 36°F | 26°F | 3.6" |
| March | 32°F | 52°F | 41°F | 3.5" |
| April | 41°F | 65°F | 52°F | 6.9" |
| May | 52°F | 74°F | 63°F | 7.1" |
| June | 62°F | 83°F | 72°F | 7.9" |
| July | 65°F | 86°F | 75°F | 8.4" |
| August | 63°F | 84°F | 73°F | 7.4" |
| September | 54°F | 78°F | 65°F | 8.9" |
| October | 44°F | 66°F | 54°F | 5.8" |
| November | 32°F | 52°F | 41°F | 4.0" |
| December | 22°F | 37°F | 29°F | 4.5" |
| Index | Seaton | Illinois | National |
| Air quality index | 32 | 41 | 42 |
| Pollution index | 640,499 | 3,148,694 | 2,726,193 |
| Measurement | Total |
| Days measured | 365 |
| Days with good air quality | 300 |
| Days with moderate air quality | 65 |
| Days w/ poor A.Q. for sensitive groups | 0 |
| Days with unhealthy air quality | 0 |
| Pollutant | Total |
| Arsenic | 0.001% |
| Benzene | 0.030% |
| Carbon Tetrachloride | 0.000% |
| Lead | 0.003% |
| Mercury | 0.000% |
| City | Population | Air Quality Index | National Avg. |
| Oquawka, IL | 1,352 | 29 | 42.0% |
| Oakville, IA | 209 | 32 | 36.0% |
| New Boston, IL | 515 | 32 | 36.0% |
| Monmouth, IL | 8,837 | 32 | 36.0% |
| Aledo, IL | 3,625 | 32 | 36.0% |
| Seaton, IL | 278 | 32 | 36.0% |
| City | Population | Air Quality Index | National Avg. |
| Meridian, CA | 278 | 44 | 12.0% |
| Rebecca, GA | 278 | 26 | 48.0% |
| Lester, IA | 278 | 36 | 28.0% |
| Lu Verne, IA | 278 | 15 | 70.0% |
| Star City, IN | 278 | 37 | 26.0% |
| Seaton, IL | 278 | 32 | 36.0% |
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