Western Washington is a region of the United States defined as that part of Washington west

West

West is a noun, adjective, or adverb indicating direction or geography.West is one of the four cardinal directions or compass points. It is the opposite of east and is perpendicular to north and south.By convention, the left side of a map is west....

 of the Cascade Mountains

Cascade Range

The Cascade Range is a major mountain range of western North America, extending from southern British Columbia through Washington and Oregon to Northern California. It includes both non-volcanic mountains, such as the North Cascades, and the notable volcanoes known as the High Cascades...

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It is known as being far wetter in climate than the eastern portion of the state, which
is due in main to the effects of the Cascades rain shadow

Rain shadow

A rain shadow is a dry area on the lee side of a mountainous area. The mountains block the passage of rain-producing weather systems, casting a "shadow" of dryness behind them. As shown by the diagram to the right, the warm moist air is "pulled" by the prevailing winds over a mountain...

. The average place in Eastern Washington only receives an average of 46.87 centimeters (18.45 inches) of precipitation per year. However, the average place in Western Washington receives an average of 167.72 centimeters (66.03 inches) of precipitation per year. The average place in Western Washington gets 168 days of measurable precipitation per year. The place that receives the most recorded precipitation is Lake Quinault with an average of 332.92 centimeters (131.07 inches) per year. The place that gets the most days of measurable precipitation is the Long Beach Experimental Station with an average of 215 days of measurable precipitation per year. In the 2010 census, Western Washington had a population of 5,229,486 out of the 6,724,540 in the entire state of Washington. This makes the population comparable to that of Minnesota with a population of 5,303,925. It has a land area of 24742 square miles (64,081.5 km²), for a population density of 211.36 people per square mile (81.61 people per square kilometer).

Counties of Western Washington

Clallam,
Clark

Clark County, Washington

Clark County is a county located in the southwestern part of the U.S. state of Washington, across the Columbia River from Portland, Oregon.Clark County was the first county of Washington, named after William Clark of the Lewis and Clark Expedition...

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Cowlitz

Cowlitz County, Washington

Cowlitz County is a county located in the U.S. state of Washington. As of the 2010 census its population was 102,410. It forms the Longview, Washington, Metropolitan Statistical Area which encompasses all of Cowlitz County. The county seat is at Kelso, and its largest city is Longview...

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Grays Harbor

Grays Harbor County, Washington

Grays Harbor County is a county in the state of Washington, in the United States of America. As of 2010, the population was 72,797. The county seat is at Montesano, and its largest city is Aberdeen. The county is named after a large estuarine bay near its southwestern corner...

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Island

Island County, Washington

Island County is a county located in the U.S. state of Washington. In 2010 census, its population was 78,506. Its county seat is Coupeville, while its largest city is Oak Harbor....

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Jefferson

Jefferson County, Washington

Jefferson County is a county located in the U.S. state of Washington, named after Thomas Jefferson. As of 2010, the population was 29,872. The county seat is at Port Townsend, which is also the county's only incorporated city....

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King

King County, Washington

King County is a county located in the U.S. state of Washington. The population in the 2010 census was 1,931,249. King is the most populous county in Washington, and the 14th most populous in the United States....

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Kitsap

Kitsap County, Washington

Kitsap County is a county located in the U.S. state of Washington, named after Chief Kitsap of the Suquamish tribe. As of 2011 state estimate, its population was 253,900. Its county seat is at Port Orchard, and its largest city is Bremerton....

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Lewis

Lewis County, Washington

Lewis County is a county located in the U.S. state of Washington. As of 2010, the population was 75,455. The county seat is at Chehalis, and its largest city is Centralia....

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Mason,
Pacific,
Pierce

Pierce County, Washington

right|thumb|[[Tacoma, Washington|Tacoma]] - Seat of Pierce CountyPierce County is the second most populous county in the U.S. state of Washington. Formed out of Thurston County on December 22, 1852, by the legislature of Oregon Territory...

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San Juan,
Skagit

Skagit County, Washington

Skagit County is a county in the U.S. state of Washington. It is named after the Skagit Indian tribe. As of 2010, the population was 116,901. It is included in the Mount Vernon-Anacortes, Washington, Metropolitan Statistical Area...

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Skamania,
Snohomish

Snohomish County, Washington

Snohomish County is a county located in the U.S. state of Washington. It is named after the Snohomish tribe. Since 2000, the county's population has grown from 606,024 to 713,335 residents , making it one of the fastest-growing in the state, ranking third in overall population after King and...

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Thurston,
Wahkiakum, and Whatcom

Whatcom County, Washington

Whatcom County is a county located in the U.S. state of Washington. Its name ultimately derives from the Lummi word Xwotʼqom, meaning "noisy water." As of 2010, the population was 201,140. The county seat is at Bellingham, which is also the county's largest city...

 Counties are in Western Washington.

Cities of note

• Aberdeen
  Aberdeen, Washington
  Aberdeen is a city in Grays Harbor County, Washington, United States, founded by Samuel Benn in 1884. Aberdeen was incorporated on May 12, 1890. The city is the economic center of Grays Harbor County, bordering the cities of Hoquiam and Cosmopolis...
  
  
• Bellevue
  Bellevue, Washington
  Bellevue is a city in the Eastside region of King County, Washington, United States, across Lake Washington from Seattle. Long known as a suburb or satellite city of Seattle, it is now categorized as an edge city or a boomburb. The population was 122,363 at the 2010 census.Downtown Bellevue is...
  
  
• Bellingham
  Bellingham, Washington
  Bellingham is the largest city in, and the county seat of, Whatcom County in the U.S. state of Washington. It is the twelfth-largest city in the state. Situated on Bellingham Bay, Bellingham is protected by Lummi Island, Portage Island, and the Lummi Peninsula, and opens onto the Strait of Georgia...
  
  
• Bremerton
  Bremerton, Washington
  Bremerton is a city in Kitsap County, Washington, United States. The population was 38,790 at the 2011 State Estimate, making it the largest city on the Olympic Peninsula. Bremerton is home to Puget Sound Naval Shipyard and the Bremerton Annex of Naval Base Kitsap...
  
  
• Everett
  Everett, Washington
  Everett is the county seat of and the largest city in Snohomish County, Washington, United States. Named for Everett Colby, son of founder Charles L. Colby, it lies north of Seattle. The city had a total population of 103,019 at the 2010 census, making it the 6th largest in the state and...
  
  
• Federal Way
  Federal Way, Washington
  Federal Way is a city in King County, Washington, United States. Federal Way is located between Seattle and Tacoma. Its western boundary is Puget Sound. It is bordered by Des Moines on the north, Kent, unincorporated King County, and Milton on the east and Tacoma and Fife on the south...
  
  
• Kelso
  Kelso, Washington
  Kelso is a city in southwest Washington State, United States, and is the county seat of Cowlitz County. At the 2010 census, the population was 11,925. Kelso is part of the Longview, Washington Metropolitan Statistical Area, which has a population of 102,410. Kelso shares its long western border...
  
  
• Longview
  Longview, Washington
  Longview is a city in Cowlitz County, Washington, United States. It is the principal city of the "Longview, Washington Metropolitan Statistical Area", which encompasses all of Cowlitz County. Longview's population was 36,648 at the time of the 2010 census and is the largest city in Cowlitz County...
  
  
• Lynnwood
  Lynnwood, Washington
  Lynnwood is a city in Snohomish County, Washington, United States. The population was 35,836 at the 2010 census, making it the fourth largest in Snohomish County and twenty-ninth largest in Washington State. The city is a mix of urban, suburban, small city, crossroads and bedroom community to many...
  
  
• Mount Vernon
  Mount Vernon, Washington
  Mount Vernon is a city in Skagit County, Washington, United States. The population was 31,743 at the 2010 census. It is one of two principal cities of and included in the Mount Vernon-Anacortes, Washington Metropolitan Statistical Area. It is the county seat of Skagit County...
  
  
• Olympia
  Olympia, Washington
  Olympia is the capital city of the U.S. state of Washington and the county seat of Thurston County. It was incorporated on January 28, 1859. The population was 46,478 at the 2010 census...
  
  
• Port Angeles
  Port Angeles, Washington
  Port Angeles is a city in and the county seat of Clallam County, Washington, United States. The population was 19,038 at the 2010 census. The area's harbor was dubbed Puerto de Nuestra Señora de los Ángeles by Spanish explorer Francisco de Eliza in 1791, but by the mid-19th century the name had...
  
  
• Silverdale
  Silverdale, Washington
  Silverdale is a census-designated place in Kitsap County, Washington, in the United States. The population was 19,204 at the 2010 census.Despite many attempts at incorporation, Silverdale remains an unincorporated community....
  
  
• Port Townsend
  Port Townsend, Washington
  Port Townsend is a city in Jefferson County, Washington, United States, approximately north-northwest of Seattle . The population was 9,113 at the 2010 census an increase of 9.3% over the 2000 census. It is the county seat and only incorporated city of Jefferson County...
  
  
• Seattle
  Seattle, Washington
  Seattle is the county seat of King County, Washington. With 608,660 residents as of the 2010 Census, Seattle is the largest city in the Northwestern United States. The Seattle metropolitan area of about 3.4 million inhabitants is the 15th largest metropolitan area in the country...
  
  
• Tacoma
  Tacoma, Washington
  Tacoma is a mid-sized urban port city and the county seat of Pierce County, Washington, United States. The city is on Washington's Puget Sound, southwest of Seattle, northeast of the state capital, Olympia, and northwest of Mount Rainier National Park. The population was 198,397, according to...
  
  
• Vancouver
  Vancouver, Washington
  Vancouver is a city on the north bank of the Columbia River in the U.S. state of Washington. Incorporated in 1857, it is the fourth largest city in the state with a 2010 census population of 161,791 as of April 1, 2010...
  
  

US Census Bureau for Washington