Environmental Hazards, Nature, Science

Unexplained “White Rain” Hits Pacific Northwest

Shiveluch volcano
The “white rain” that fell on the Pacific Northwest last weekend may have been caused by the eruption of the Shiveluch volcano in Russia.
Image: Shutterstock

Residents of Washington, Oregon, and northern California experienced a strange sort of rain last Saturday: milky white ash. Samples were collected and sent for analysis, but no certain identification has been made.

Officials from the Walla Walla County Emergency in Washington said that people started calling in and reporting “white stuff” falling and covering their vehicles last Saturday. There has also been extensive rain in the area.

Some scientists suggest the ash might have originated in the eruption of the Russian volcano Shiveluch, which released a 20,000-foot plume of ash in January. In addition, there was another eruption last Thursday. The ash could have drifted on a jet stream to the Pacific Northwest of the United States.

There was also a volcanic eruption in Southwest Colima, Mexico on February 4, making it a potential culprit as well. This volcano is located 2,000 miles from Washington, Oregon, and northern California, but a jet stream could have carried the ash in from this location as well.

The idea of volcanic activity affecting far away areas is nothing new. Researchers from Rice University state that in 1980 there were traces of ash from the Mount St. Helens eruption that traveled as far as Oklahoma and Colorado. And scientists at the University of Oregon pointed to the aftermath of the Krakatau volcanic eruption in 1883, when ashes reached as far as Singapore, 840 kilometers north of the volcano.

Another possible cause, according to CNN meteorologist Derek Van Dam, could be the wildfires in Idaho and Oregon, or potentially the intense dust storm that hit northwest Nevada recently, with winds up to 60 MPH.

The US National Weather Service will be conducting an investigation into the atmospheric issues that could have caused the white, ashy rain. They will focus on tests that look at the dispersion and reaction of pollutants in the atmosphere.