Rock Falls, IL Weather - Forecast & Monthly Averages

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TEMPERATURE
HUMIDITY
PRESSURE
WIND COND.

Weather Quick Facts

The highest monthly average temperature in Rock Falls for August is 73.3 degrees
The lowest monthly average temperature in Rock Falls for December is 23.1 degrees
The most monthly precipitation in Rock Falls occurs in August with 9.2 inches
The air quality index in Rock Falls is equal to the national average
The pollution index in Rock Falls is 23% better than the national average

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Rock Falls 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	18°F	33°F	25°F	2.9"
February	17°F	32°F	24°F	2.5"
March	31°F	52°F	39°F	4.5"
April	39°F	65°F	50°F	6.4"
May	50°F	76°F	62°F	3.5"
June	61°F	86°F	73°F	6.1"
July	61°F	86°F	73°F	7.8"
August	64°F	85°F	73°F	9.2"
September	55°F	82°F	67°F	3.9"
October	45°F	69°F	56°F	1.9"
November	30°F	52°F	40°F	4.2"
December	17°F	31°F	23°F	1.5"

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Rock Falls 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	Rock Falls	Illinois	National
Air quality index	42	41	42
Pollution index	2,097,740	3,148,694	2,726,193

Rock Falls air quality

Measurement	Total
Days measured	364
Days with good air quality	268
Days with moderate air quality	96
Days w/ poor A.Q. for sensitive groups	0
Days with unhealthy air quality	0

Air quality details

Pollutant	Total
Arsenic	0.001%
Benzene	0.060%
Carbon Tetrachloride	0.000%
Lead	0.001%
Mercury	0.300%

Average monthly Rock Falls temperature with heat index

Rock Falls monthly precipitation with daily maximum

Rock Falls monthly snow depth with daily maximum

Rock Falls monthly wind speed information

Nearby cities with good air quality

City	Population	Air Quality Index	National Avg.
Ohio, IL	509	0	100.0%
Dixon, IL	15,544	42	16.0%
Milledgeville, IL	987	42	16.0%
Prophetstown, IL	1,965	42	16.0%
Walnut, IL	1,340	42	16.0%
Rock Falls, IL	8,914	42	16.0%

Cities with similar population

City	Population	Air Quality Index	National Avg.
Mahopac, NY	8,914	36	28.0%
Berkeley, MO	8,912	54	8.0%
Monmouth Junction, NJ	8,911	41	18.0%
Terrace Heights, WA	8,917	38	24.0%
Alma, MI	8,918	26	48.0%
Rock Falls, IL	8,914	42	16.0%

Source: The Rock Falls, 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.