yep, fires are an increasing fact of life and not just in these cities.
anywhere is susceptible, in 2020 the smoke in Spokane hit 450 ppm due to wildfires in Canada and lingered for weeks
In August 2023, smoke from multiple fires caused air quality in Bellingham and eastern Washington to be among the worst in the country, with an Air Quality Index (AQI) in the 400–500 range.
and not just here in the PNW:
"In the past decade, smoke from wildland fires has become a major contributor to poor air quality in the U.S. We identify surface smoke influenced days using a combination of the NOAA Hazard Mapping System (HMS) Fire and Smoke Product and surface PM2.5 data. In total we use data for 2019-2023 from more than 800 PM2.5 monitors, in more than 350 different core based statistical areas (CBSA), covering approximately 90% of the US population.
Averaged over this 5 year period, the highest PM2.5 exposure due to smoke is found in CBSAs located in Oregon, Nevada, California, Washington, North Dakota and Minnesota. Amongst the most populous regions in the country, some also experience high PM2.5 exposure in selected years. The New York, Dallas, Chicago, Atlanta and Washington D.C. CBSAs had high PM2.5 smoke exposure in 2023, whereas the Los Angeles, Phoenix and Riverside CBSAs had their highest exposures in 2020"