Mason City, IL Weather - Forecast & Monthly Averages

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TEMPERATURE
HUMIDITY
PRESSURE
WIND COND.

Weather Quick Facts

The highest monthly average temperature in Mason City for July is 75.7 degrees
The lowest monthly average temperature in Mason City for January is 27.8 degrees
The most monthly precipitation in Mason City occurs in September with 11.5 inches
The air quality index in Mason City is 5% better than the national average
The pollution index in Mason City is 53% better than the national average

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Mason City Average Temperature

In the event that the weather data was unavailable for this city, estimates based upon nearby cities were used.
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"

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Mason City air quality index & pollution index

In the event that the air quality/pollution data was unavailable for this city, estimates based upon nearby cities were used.
Index	Mason City	Illinois	National
Air quality index	40	41	42
Pollution index	1,277,890	3,148,694	2,726,193

Mason City air quality

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

Air quality details

Pollutant	Total
Arsenic	0.010%
Benzene	0.050%
Carbon Tetrachloride	0.000%
Lead	0.010%
Mercury	0.002%

Average monthly Mason City temperature with heat index

Mason City monthly precipitation with daily maximum

Mason City monthly snow depth with daily maximum

Mason City monthly wind speed information

Nearby cities with good air quality

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%

Cities with similar population

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%

Source: The Mason City, IL weather data displayed above is derived from the NOAA (National Oceanic and Atmospheric). Air quality and pollution data is derived from the EPA (United States Environmental Protection Agency). Air quality and pollution levels measured in a particular area may not be representative of the entire county.