SmogRank / World / United States / Washington / January 2025
Most polluted cities in Washington, United States, January 2025
40 cities in Washington, United States ranked by their average PM2.5 over the 31 days. Worst: Parkland at 15.4 µg/m³, #465 of 2,426 cities in the world. Cleanest: Mount Vernon at 3.0. A city needs measurements on 70% of the days to be ranked.
Ranked by unhealthy days: the share of each city's measured days with a daily mean over 35.4 µg/m³ (US AQI 101+), Unhealthy for Sensitive Groups or worse on the US EPA's scale. Ties go to the higher average.
- 1Parkland 0%
- 2Renton 0%
- 3Yakima 0%
- 4Tacoma 0%
- 5Toppenish 0%
- 6Auburn 0%
- 7Spokane 0%
- 7Spokane Valley 0%
- 9Lacey 0%
- 9White Center 0%
- 11Port Angeles 0%
- 12Sunnyside 0%
- 13Longview 0%
- 13Vancouver 0%
- 15Chehalis 0%
- 15Seattle 0%
- 17Shoreline 0%
- 18Ellensburg 0%
- 18Shelton 0%
- 20Walla Walla 0%
- 21Wenatchee 0%
- 22Mead 0%
- 23Lynden 0%
- 24Bellingham 0%
- 25Port Townsend 0%
- 25Picnic Point-North Lynnwood 0%
- 27Prosser 0%
- 28Moses Lake 0%
- 29Anacortes 0%
- 29Bremerton 0%
- 31Ephrata 0%
- 31Ridgefield 0%
- 33Airway Heights 0%
- 34Aberdeen 0%
- 35North Bend 0%
- 36Bellevue 0%
- 37Quincy 0%
- 38Pullman 0%
- 38Tri-Cities 0%
- 40Mount Vernon 0%
The US EPA's Air Quality Index for PM2.5 (2024 breakpoints). Show values as: µg/m³ · US AQI · India AQI · China AQI · European AQI · UK DAQI · Canada AQHI+. About the scales
All cities in the world, January 2025 · All cities in United States, January 2025 · Washington now
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SmogRank, most polluted cities in Washington, United States, PM2.5, January 2025, smogrank.com/us/region/washington/history/2025-01 (accessed 6 Oct 2026).
You're welcome to reuse a single chart, image or figure with this citation and a link. Terms. Raw monitor readings in bulk are published by OpenAQ, under each provider's licence.