Grass Valley, CA Weather - Forecast & Monthly Averages

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TEMPERATURE	63
HUMIDITY	55
PRESSURE	101860
WIND COND.

Weather Quick Facts

The highest monthly average temperature in Grass Valley for July is 70.9 degrees
The lowest monthly average temperature in Grass Valley for December is 39.2 degrees
The most monthly precipitation in Grass Valley occurs in December with 11.7 inches
The air quality index in Grass Valley is 5% worse than the national average
The pollution index in Grass Valley is 57% worse than the national average

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Grass Valley 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	35°F	49°F	41°F	7.8"
February	35°F	47°F	40°F	8.4"
March	36°F	49°F	41°F	10.1"
April	38°F	54°F	45°F	5.7"
May	46°F	62°F	53°F	3.7"
June	55°F	71°F	62°F	1.4"
July	64°F	79°F	71°F	0.1"
August	63°F	79°F	70°F	0.1"
September	58°F	74°F	65°F	1.4"
October	48°F	63°F	54°F	4.8"
November	40°F	53°F	46°F	7.3"
December	34°F	46°F	39°F	11.7"

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Grass Valley 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	Grass Valley	California	National
Air quality index	44	55	42
Pollution index	4,289,310	10,473,190	2,726,193

Grass Valley air quality

Measurement	Total
Days measured	365
Days with good air quality	239
Days with moderate air quality	124
Days w/ poor A.Q. for sensitive groups	2
Days with unhealthy air quality	0

Air quality details

Pollutant	Total
Arsenic	0.050%
Benzene	0.070%
Carbon Tetrachloride	0.001%
Lead	0.060%
Mercury	0.010%

Average monthly Grass Valley temperature with heat index

Grass Valley monthly precipitation with daily maximum

Grass Valley monthly snow depth with daily maximum

Grass Valley monthly wind speed information

Nearby cities with good air quality

City	Population	Air Quality Index	National Avg.
Nevada City, CA	3,145	44	12.0%
North San Juan, CA	151	44	12.0%
Colfax, CA	2,258	44	12.0%
Alta, CA	703	44	12.0%
Penn Valley, CA	1,073	44	12.0%
Grass Valley, CA	12,817	44	12.0%

Cities with similar population

City	Population	Air Quality Index	National Avg.
Brighton, ON	12,811	n/a
Herrin, IL	12,806	43	14.0%
Cedar Lake, IN	12,830	55	10.0%
Joppatowne, MD	12,833	46	8.0%
Jacksonville, AL	12,796	43	14.0%
Grass Valley, CA	12,817	44	12.0%

Source: The Grass Valley, CA 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.