Air Quality Index in Seattle, WA

Traffic emissions are a primary source of pollution in Seattle, especially during peak commuting hours. Weather patterns, including rain and wind, usually help clear the air, but on dry, calm days, pollutants can linger, leading to poorer air quality. Wildfire season, which often occurs in late summer and early fall, can bring smoke from nearby regions, significantly lowering air quality. Additionally, industrial activities and port operations contribute pollutants that can impact the air, particularly in areas near the waterfront and industrial zones.

AQI in Seattle is usually worst in late summer and early fall, especially during wildfire season when smoke from nearby fires can drift into the city, lowering air quality. Dry weather and occasional temperature inversions, which trap pollutants close to the ground, also contribute to higher pollution levels during this period. Additionally, winter months can sometimes see poorer air quality due to wood-burning activities and stagnant weather that limits airflow and prevents pollutants from dispersing.

Certain areas in Seattle tend to have better air quality, usually due to less traffic and more natural green spaces. Neighborhoods farther from highways and industrial zones, such as Magnolia, Green Lake, and parts of West Seattle, often experience cleaner air. Areas near the coast, like Alki Beach, also benefit from ocean breezes that help disperse pollutants. Additionally, neighborhoods near parks and forests, such as those by Discovery Park and Seward Park, can have better air quality due to the natural air filtration provided by trees and open spaces.