2024 wildfire season: air quality in review

Although a few fires continue to burn in the state, smoke levels remain low, and the forecasted weather is not conducive to wildfire growth. Let's take a look at how this wildfire season's air quality compares to previous years.

In terms of the number of smoke-impacted days, this summer looked more like the relatively smoke-free summers of 2016 and 2019 rather than more recent years. The summer wasn't smoke-free, but we avoided significant, widespread, and prolonged smoke impacts. One way to put this year in perspective is to review the total number of smoky days at air quality monitoring sites in Washington since 2012, broken up into region and only including days when the air quality reached Unhealthy for Sensitive Groups or worse:

For all regions, the number of smoky days this summer was much less than previous years. There were only 7 days of Unhealthy air quality in the state this summer--that's from 115 air quality monitors and sensors that continuously measure PM2.5. To put that number into context, the 2020-2023 seasons averaged 206 days of Unhealthy or worse air quality. Looking a little further, there were only 413 hours (about 12% of the total monitoring hours) of Unhealthy or worse air quality this summer. That's an order of magnitude less than the number of Unhealthy or worse hours in 2023 (3,129 hours). About 20% of those 413 hours were associated with 4th of July fireworks.

We can also put this season into context by estimating approximately how many Washingtonians were exposed to extended periods of poor air quality in comparison with recent smoke events. While communities near wildfires experienced smoke this summer, far fewer Washingtonians were exposed to unhealthy air compared to the past few years.

This wildfire season Washington largely escaped significant smoke impacts from neighboring states and Canada. While there were a few large wildfires in Central and Eastern WA (i.e., the Pioneer, Williams Mine, Swawilla, Retreat, Cougar Creek Fires), nearby communities were the most impacted. Favorable meteorological conditions were also on our side, including early season precipitation and a lack of significant easterly wind events. Quick actions by firefighters also helped to minimize smoke production from active fires. Thanks to everyone that recreated safely during critical fire weather conditions.