| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 18°F | 34°F | 25°F | 3.2" |
| February | 19°F | 36°F | 27°F | 3.2" |
| March | 32°F | 51°F | 41°F | 5.1" |
| April | 42°F | 64°F | 52°F | 6.5" |
| May | 53°F | 74°F | 63°F | 7.0" |
| June | 62°F | 82°F | 72°F | 7.0" |
| July | 65°F | 85°F | 74°F | 7.2" |
| August | 64°F | 84°F | 73°F | 8.3" |
| September | 57°F | 78°F | 66°F | 7.1" |
| October | 45°F | 65°F | 54°F | 6.0" |
| November | 34°F | 52°F | 42°F | 4.6" |
| December | 23°F | 38°F | 30°F | 3.8" |
| Index | Hopewell | Illinois | National |
| Air quality index | 48 | 41 | 50 |
| Pollution index | 339,156 | 3,347,295 | 5,066,862 |
| Measurement | Total |
| Days measured | 365 |
| Days with good air quality | 207 |
| Days with moderate air quality | 132 |
| Days w/ poor A.Q. for sensitive groups | 21 |
| Days with unhealthy air quality | 5 |
| Pollutant | Total |
| Arsenic | 0.000% |
| Benzene | 0.020% |
| Carbon Tetrachloride | 0.000% |
| Lead | 0.000% |
| Mercury | 0.000% |
| City, State | Population | Air Quality Index | National Avg. |
| Magnolia, IL | 320 | 1 | 98% |
| McNabb, IL | 305 | 1 | 98% |
| Bradford, IL | 657 | 48 | 4% |
| Henry, IL | 2,348 | 48 | 4% |
| Sparland, IL | 420 | 48 | 4% |
| Hopewell, IL | 415 | 48 | 4% |
| City, State | Population | Air Quality Index | National Avg. |
| Seligman, AZ | 415 | 41 | 18% |
| Hayti, SD | 415 | 36 | 28% |
| Edgar, NE | 415 | 265 | 430% |
| McNeil, AR | 415 | 4 | 92% |
| Cumming, IA | 415 | 41 | 18% |
| Hopewell, IL | 415 | 48 | 4% |