Washington and Oregon officials have reported the occurrence of somewhat milky ash substance that covered vehicles and homes. Speculations suggested that the substance came from the Russian volcano Shiveluch, which is about 4,000 miles in distance, while another official speculated that the ashy substance came from a 2,000-mile Mexican volcano.
Despite speculations, other officials believe that the substance could have come from atmospheric remnants due to a recent wildfire nearby, or from dust brought about by nearby storm. The United States National Weather Service has been investigating the reports, including the recreation of atmospheric flows from the previous days. The agency also noted in its Facebook post the so-called HYSPLIT or Hybrid Single Particle Lagrangian Integrated Trajectory program so as to stimulate how pollutants within the ambient atmosphere dissolve and react within the atmosphere.