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 is still some smoke lingering in central California due to the fires there during the past few weeks. In the Mississippi Valley, there are many fires with light plumes. Most of this smoke has been moving northward. The second image below, courtesy of GASP EAST, shows the retrieved AOD 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. Specifically, the large concentration of smoke from the Mississippi Valley fires are increasing the AOD. There does appear to be an increase in AOD across the eastern portion of the country that does not coincide with smoke plumes. This may be due to increased sulfate extinction with the humid sulfate particles. The Relative Humidity values between 80-95% along the eastern coast and temperatures around 90 degrees F.
The first image, courtesy EPA AIRNOW, shows the Mid Atlantic and Great Lakes regions for the day. Many of these code oranges and yellows were due to ozone. With the warm air rushing in there is an increase in ozone production. The next image, courtesy GEOS-5, shows the modeled sulfate only AOD [550 nm] for the eastern half of the country today. These model results show that there has been an increase in sulfate concentrations in the Mid Atlantic region, which may be causing additional code oranges/yellows.