Grinnell, IA Weather - Forecast & Monthly Averages

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TEMPERATURE	38
HUMIDITY	66
PRESSURE	102570
WIND COND.

Weather Quick Facts

The highest monthly average temperature in Grinnell for July is 74.3 degrees
The lowest monthly average temperature in Grinnell for January is 21.3 degrees
The most monthly precipitation in Grinnell occurs in June with 7.8 inches
The air quality index in Grinnell is 7% better than the national average
The pollution index in Grinnell is 75% better than the national average

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Grinnell 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	14°F	30°F	21°F	1.4"
February	17°F	33°F	24°F	2.7"
March	31°F	50°F	39°F	3.7"
April	40°F	63°F	50°F	7.2"
May	52°F	74°F	62°F	7.7"
June	62°F	82°F	72°F	7.8"
July	65°F	85°F	74°F	7.6"
August	63°F	82°F	72°F	7.4"
September	54°F	77°F	64°F	7.1"
October	43°F	64°F	53°F	6.9"
November	32°F	50°F	40°F	3.7"
December	20°F	35°F	27°F	5.3"

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Grinnell 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	Grinnell	Iowa	National
Air quality index	39	39	42
Pollution index	684,464	1,154,535	2,726,193

Grinnell air quality

Measurement	Total
Days measured	365
Days with good air quality	306
Days with moderate air quality	59
Days w/ poor A.Q. for sensitive groups	0
Days with unhealthy air quality	0

Air quality details

Pollutant	Total
Arsenic	0.000%
Benzene	0.010%
Carbon Tetrachloride	0.001%
Lead	0.001%
Mercury	0.000%

Average monthly Grinnell temperature with heat index

Grinnell monthly precipitation with daily maximum

Grinnell monthly snow depth with daily maximum

Grinnell monthly wind speed information

Nearby cities with good air quality

City	Population	Air Quality Index	National Avg.
Haverhill, IA	170	37	26.0%
Ferguson, IA	125	37	26.0%
Laurel, IA	194	37	26.0%
Gilman, IA	543	37	26.0%
Holiday Lake, IA	330	39	22.0%
Grinnell, IA	9,069	39	22.0%

Cities with similar population

City	Population	Air Quality Index	National Avg.
Charlotte, MI	9,069	36	28.0%
Heath, TX	9,069	51	2.0%
Lake Elmo, MN	9,071	46	8.0%
Ogden, NC	9,071	34	32.0%
Hillview, KY	9,066	49	2.0%
Grinnell, IA	9,069	39	22.0%

Source: The Grinnell, IA 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.