Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
January | 24°F | 38°F | 31°F | 6.8" |
February | 23°F | 37°F | 29°F | 3.4" |
March | 35°F | 56°F | 45°F | 3.0" |
April | 43°F | 65°F | 54°F | 4.2" |
May | 54°F | 78°F | 66°F | 3.1" |
June | 64°F | 86°F | 75°F | 8.1" |
July | 65°F | 86°F | 76°F | 4.0" |
August | 68°F | 89°F | 78°F | 3.9" |
September | 59°F | 85°F | 72°F | 7.7" |
October | 49°F | 71°F | 60°F | 7.1" |
November | 37°F | 56°F | 45°F | 6.1" |
December | 24°F | 37°F | 30°F | 2.5" |
Index | Decatur | Illinois | National |
Air quality index | 44 | 41 | 42 |
Pollution index | 703,218 | 3,148,694 | 2,726,193 |
Measurement | Total |
Days measured | 365 |
Days with good air quality | 255 |
Days with moderate air quality | 110 |
Days w/ poor A.Q. for sensitive groups | 0 |
Days with unhealthy air quality | 0 |
Pollutant | Total |
Arsenic | 0.001% |
Benzene | 0.020% |
Carbon Tetrachloride | 0.000% |
Lead | 0.000% |
Mercury | 0.000% |
City | Population | Air Quality Index | National Avg. |
Dalton City, IL | 717 | 44 | 12.0% |
LaPlace, IL | 128 | 44 | 12.0% |
Niantic, IL | 657 | 44 | 12.0% |
Forsyth, IL | 3,474 | 44 | 12.0% |
Maroa, IL | 1,982 | 44 | 12.0% |
Decatur, IL | 71,857 | 44 | 12.0% |
City | Population | Air Quality Index | National Avg. |
Frederick, MD | 71,843 | 40 | 20.0% |
Lauderhill, FL | 71,827 | 41 | 18.0% |
Pawtucket, RI | 71,821 | 44 | 12.0% |
Pittsburg, CA | 71,723 | 40 | 20.0% |
Redlands, CA | 71,680 | 89 | 78.0% |
Decatur, IL | 71,857 | 44 | 12.0% |