WSU studies origin of dirty rain that hit Wash.

Residents of Eastern Washington reported rainfall that contained milky-­colored or light gray dirt on Friday, Feb. 6.

A Washington State University researcher thinks he knows the cause of a mysterious "milky rain" that hit parts of the Pacific Northwest last Friday.

Meteorologist Nic Loyd says the dirty rain was the result of a rare weather phenomenon that began near an ancient saline lake nearly 500 miles away.

Loyd believes a meshing of weather systems that started in southern Oregon ultimately caused dirty­ white­-colored raindrops to fall in eastern Washington and northeast Oregon.

The National Weather Service received reports Friday of ashy debris coating vehicles and windows in more than 15 cities, including Spokane, the Tri­Cities, and Hermiston, Oregon.

While the ash­like substance has not yet been scientifically confirmed, the Weather Service says it's believed to be from a dust storm that struck Oregon's Summer Lake on Thursday night.

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Copyright The Associated Press