Déjà vu today and tomorrow. But not in comparison with previous years

Air quality degraded in western WA on Monday with the Puget Sound area experiencing Unhealthy air at times while the coast and southwest WA had Good to Moderate air. Tuesday and possibly Wednesday will be no different.

No Good air quality recorded anywhere in eastern WA yesterday, with most locations reading Unhealthy. And that will likely be the story for the next few days.

Déjà vu ends there. When compared to previous years, this wildfire season is unprecedented in the widespread nature of compromised air quality. Here's an animation of the worst days during the wildfires of 2012, 2015 and 2017, showing air quality conditions overlaid on a satellite map. Way more people were exposed to poor air this year than in the recent past.



However the percentage of time people breathed unhealthy air in 2017 is not as bad as past years, as shown by the barplot below. At least thus far. For instance, people in Spokane county were exposed to bad air about 5% of the time this year, while they had to deal with bad air for twice as long in 2015.

The # of acres burned, locations of fires and meteorological patterns all play roles in assessing public exposure to smoke. We will compile more data as it becomes available.

On an optimistic note, we're quite confident that the weekend will usher in a substantial shift in winds that will both cool the state and help dissipate smoke.