Animation of US PM2.5 Air Pollution in 2025

This video shows hourly PM2.5 air pollution across the United States for 2025:

I did the same thing for 2023 using the Purple Air sensor network. Unfortunately they are now charging for access to the data, however the official AirNow network has an API and so I used that instead. The lack of sensors at the local level is frustrating, but it works fine for this nationwide view.

The 4th of July is pretty incredible (see the photo at the top of the post).

In San Francisco this was a pretty mild year for wildfire smoke. We did see a few days in mid-July from the Butler and Green fires. Canada was a big factor again, look particularly around June 3-5 and late July. And of course the Palisades fire, starting on Jan 7.