The NRL/Monterey Aerosol image above shows that there is a high concentration of dust in upper China. The deep red shows that the concentration of dust in certain areas can lead from 5120-10240 ug/m**3.
The NASA Worldview Image above supports the idea of a high dust concentration of upper China and Mongolia. This dust may be in concurrence with the trend of Asian Dust in which during the Spring months, the wind picks up dust in from northern China and Mongolia and carries it across East Asia.
The picture above is an image from the GOES 16 satellite. It shows that there were multiple fires found that started on March 5th. The AirNow Map below shows that these fires could have released smoke leading to a Moderate PM 2.5 level (51-100 ppb, in yellow) in the Midwest.
The NRL/Monterey Aerosol above supports this claim as there is a high concentration of surface smoke in the midwest with concentrations in the Midwest region reaching from 64-128 ug/m**3.