Washington and Oregon residents have reported a mysterious ash covering parts of the region, describing it as "white stuff" and "milky rain," CNN reports. A statement from Walla Walla County Emergency Management yesterday said the ash is "more than likely from the Volcano Shiveluch," which is in Russia and spewed a 22,000-foot ash plume late last month, depositing ash "in a widespread area, including Washington and Oregon." But, the statement noted, there "are a number of volcanoes that are currently active. The source of the material has not been scientifically confirmed."
A CNN meteorologist as well as a meteorologist contacted by the Spokesman Review theorize the ash could be coming from an active volcano in Mexico that erupted Wednesday—it's more than 2,000 miles away, and the aforementioned Russian volcano is 4,000 miles away. The National Weather Service in Spokane has posted pictures of cloudy rainwater, and noted yesterday, "We have heard a few theories thus far including; volcanic ash from Mexico or Russia, dust picked up from last night's strong winds, or perhaps ash from last year's wildfires over SE Oregon/SW Idaho. We still don't have a definitive answer."