Visibility of less than a quarter mile has made driving treacherous in some parts of Eastern Washington.
The Washington State Patrol reported several crashes in Adams County on Interstate 90 early Friday.
The National Weather Service said some roadways are slippery because temperatures are near freezing.
The fog is expected to lift by 10 a.m. After that, rain is expected with a high temperature in the mid-40s in Spokane.
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