The first image below, courtesy NOAA HMS, shows the fire locations across the United States. The red dots correspond to active fires, and the grey areas are plumes. There are very light plumes in the Pacific Northwest region. These fires have been burning steadily for the past few days. There are also some small patches of fires in the Mississippi Valley. The image below, courtesy GASP MODIS (Terra satellite), shows the AOD image for the country today. You can see that most of these raised values correspond to more optically thick areas, which correspond to the fires and smoke debris throughout the nation. The raised values in the Pacific Southwest, specifically in southern Nevada, may be due to dust.
The first image below shows the image for EPA AIRNOW AQI values for the Pacific Northwest region. Most of these raised values are due to the continuing fires as mentioned above. Below, in the NOAA dust national forecast, there is large amounts of dust forecasted to be in the Southwest.