Mercer Island, WA Weather - Forecast & Monthly Averages

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TEMPERATURE	54
HUMIDITY	77
PRESSURE	101320.75
WIND COND.	200 20.4

Weather Quick Facts

The highest monthly average temperature in Mercer Island for August is 67.5 degrees
The lowest monthly average temperature in Mercer Island for December is 41.4 degrees
The most monthly precipitation in Mercer Island occurs in November with 6.6 inches
The air quality index in Mercer Island is 7% worse than the national average
The pollution index in Mercer Island is 60% better than the national average

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Mercer Island 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	36°F	49°F	42°F	5.1"
February	37°F	52°F	44°F	3.8"
March	40°F	55°F	47°F	4.9"
April	43°F	61°F	51°F	3.1"
May	49°F	68°F	57°F	2.2"
June	54°F	72°F	62°F	1.5"
July	58°F	79°F	67°F	0.4"
August	58°F	79°F	68°F	0.6"
September	54°F	73°F	62°F	1.6"
October	47°F	62°F	54°F	3.9"
November	40°F	53°F	47°F	6.6"
December	36°F	48°F	41°F	6.1"

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Mercer Island 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	Mercer Island	Washington	National
Air quality index	45	36	42
Pollution index	1,081,430	4,541,850	2,726,193

Mercer Island air quality

Measurement	Total
Days measured	365
Days with good air quality	236
Days with moderate air quality	127
Days w/ poor A.Q. for sensitive groups	2
Days with unhealthy air quality	0

Air quality details

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

Average monthly Mercer Island temperature with heat index

Mercer Island monthly precipitation with daily maximum

Mercer Island monthly snow depth with daily maximum

Mercer Island monthly wind speed information

Nearby cities with good air quality

City	Population	Air Quality Index	National Avg.
Manchester, WA	6,050	18	64.0%
Southworth, WA	2,300	18	64.0%
Beaux Arts Village, WA	396	45	10.0%
Kent, WA	130,038	45	10.0%
Duvall, WA	7,979	45	10.0%
Mercer Island, WA	25,820	45	10.0%

Cities with similar population

City	Population	Air Quality Index	National Avg.
Kankakee, IL	25,818	55	10.0%
Mauldin, SC	25,829	46	8.0%
Holbrook, NY	25,794	43	14.0%
Socastee, SC	25,846	14	72.0%
Lebanon, PA	25,779	42	16.0%
Mercer Island, WA	25,820	45	10.0%

Source: The Mercer Island, WA 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.