The NOAA Hazard Mapping System and Fire and Smoke Product image above shows two sources of heavy concentration of smoke originating from Oregon and British Columbia.
The NOAA Aerosol Watch image above supports this claim as there is a similar cloud of dense AODs that follows the same path as shown by the image above.
The Copernicus Global Forecast Plot image above shows that the majority of the aerosols from the two images above are most likely from biomass burning.
The Canadian Fire Danger Map shows an increased concentration of Fire Hotspots in British Columbia. CNN reports that many of these fires could have been supported by a heatwave that struck the area. With temperatures reaching 121 degrees Fahrenheit in some areas, the fires were able to spread quickly.
The AirNow Map image above shows that these fires also released smoke that increased P.M levels across America and Canada with some regions reaching Unhealthy P.M. levels (Red,151-200). INCIWEB reports that in Oregon there is the Bootleg Fire that has burned over 364 thousand acres and is only 30 percent contained.