As we await the rain likely to end this weekend, this may be our last post for Summer 2021. So we’re focusing on the two areas most affected by smoke in summer 2021: parts of Yakima and Okanogan Prefectures.
Fires in the Metho Valley caused poorer air quality in Okanogan County earlier in the season than in previous years. The Schneider Springs fire in western Yakima County has been causing problems since August 4. Here is a chart of all screens in each region that are averaged together on a daily basis. We’ve included the low-cost PurpleAir sensor data by tweaking it with the same correction factor as in the map above.

To visualize the average summer PM2.5 In each community, we built an interactive map by integrating satellite data, air quality model data, and all available monitoring data. We used the same screens as above, but only included PurpleAir sensors that reported at least one month of data. More geeky details are available upon request.
Click on the image below to view the interactive version.

Disclaimer: This map is for informational purposes only. It does not establish legal liability and should not be used to distinguish differences in air quality between a front yard and a backyard.
You can see the places that are most affected: near the fires and all the high terrain where they hit the columns, followed by the nearby valleys where the smoke pours into them. Since these are about 3 month averages, they cannot be directly compared to the daily and annual Federal Prime Minister’s2.5 35 and 12 μg/m³, respectively.
Not to underestimate the smoke that has plagued other parts of the state, but the sad reality people in those two areas have faced is even worse.