Add Yahoo as a preferred source to see more of our stories on Google. When Mount St. Helens erupted on May 18, 1980, it caused enormous devastation. The eruption triggered mudslides, an explosion, and ...

The 1980 blast remains the deadliest volcanic eruption in U.S. history. More than 300 miles from the volcano, cities like Pullman, Washington, and Moscow, Idaho, were covered in ash. A 23-year-old ...