Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
January | 20°F | 37°F | 28°F | 2.6" |
February | 21°F | 39°F | 29°F | 3.2" |
March | 34°F | 55°F | 43°F | 4.1" |
April | 44°F | 67°F | 55°F | 6.7" |
May | 54°F | 76°F | 65°F | 4.6" |
June | 63°F | 85°F | 74°F | 8.5" |
July | 66°F | 87°F | 76°F | 11.2" |
August | 64°F | 86°F | 74°F | 8.1" |
September | 56°F | 80°F | 67°F | 11.5" |
October | 46°F | 68°F | 56°F | 6.3" |
November | 34°F | 54°F | 43°F | 5.1" |
December | 25°F | 40°F | 32°F | 5.3" |
Index | Mason City | Illinois | National |
Air quality index | 40 | 41 | 42 |
Pollution index | 1,277,890 | 3,148,694 | 2,726,193 |
Measurement | Total |
Days measured | 360 |
Days with good air quality | 287 |
Days with moderate air quality | 73 |
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 | 0.000% |
Lead | 0.010% |
Mercury | 0.002% |
City | Population | Air Quality Index | National Avg. |
New Holland, IL | 257 | 40 | 20.0% |
Elkhart, IL | 459 | 40 | 20.0% |
Greenview, IL | 920 | 40 | 20.0% |
Oakford, IL | 193 | 40 | 20.0% |
Petersburg, IL | 2,564 | 40 | 20.0% |
Mason City, IL | 2,342 | 40 | 20.0% |
City | Population | Air Quality Index | National Avg. |
Bay, AR | 2,341 | 45 | 10.0% |
Franklinton, NC | 2,341 | 46 | 8.0% |
Fairfield Bay, AR | 2,343 | 45 | 10.0% |
Somers, CT | 2,343 | 40 | 20.0% |
Wrens, GA | 2,343 | 47 | 6.0% |
Mason City, IL | 2,342 | 40 | 20.0% |