Mount St. Helens erupted 40 years ago, killing 57

RAW: Scenes from Mount St. Helens eruption

Monday marks 40 years since the disastrous eruption of Mount St. Helens. It remains the deadliest volcanic eruption in U.S. history.

At 8:32 a.m. on May 18, 1980, an earthquake triggered the largest landslide in recorded history, setting off massive explosions blasting rocks, ash, volcanic gas and steam upward and outward.

>>PHOTOS: Mount St. Helens over the years

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The earthquake and lateral blast that took out the north side of the mountain also took off the top 1,300 feet of the volcano.

An 80,000-foot plume of ash darkened skies even hundreds of miles from the volcano.

The eruption destroyed hundreds of homes and leveled 185 miles of highway.

Fifty-seven people were killed, including Steve Dill's father and stepmother, Robert and Ellen Dill.

“It's difficult when you lose someone to a natural disaster like that. People are absolutely stunned when they hear your parents were killed in a volcano,” said Steve Dill.

Winds blew 520 million tons of ash across the country.

Francisco Valensuela was just west of Mount St. Helens when the mountain blew. He said he ran to his car for safety.

“I thought in fact that we were going to suffocate for a while. It was an unimaginable kind of thing to witness. You could not understand it. You could not comprehend it,” Valensuela said.

Mudflow rushed down the Toutle River Valley, carrying trees and debris.

KIRO 7 employees described where they were when the eruption happened.

Anchor Steve Raible: “I was still playing for the Seahawks at that time, so I was on vacation my wife in Hawaii with friends. In fact, we were getting ready to go out and Jack Sikma and Wally Walker, who were Sonics at the time, happened to be over there vacationing as well – they stopped by. It was amazing. We saw some of the coverage on television in Hawaii, but we really didn’t get a sense for it until we got back to Seattle and then watched the coverage here on KIRO 7 and some of the other stations, and we even got some of the stations in Portland as well on satellite.”

Consumer reporter Jesse Jones: “I was mowing the lawn at my dad’s house in Lakewood, Washington. We go take a break. Walk in the house, turn on the TV. ‘Oh my gosh. It’s the volcano. It’s gone crazy.’ People – you know, death destruction, the whole nine (yards). I’m like, ‘Wow, this is bad dad, this is really horrible.’ And dad looked at me and said, ‘I think it’s time we get back to that lawn.”

Reporter Amy Clancy: “I was riding my bike in my neighborhood in Lakewood with a buddy of mine. All of a sudden we heard this huge rumbling and we looked southeast and we saw this big huge mushroom cloud.”

Anchor Michelle Millman: “This was a Sunday so obviously, you know, we weren’t in school it was a Sunday morning. My dad was out of town on business in Oregon and he couldn’t get home because I-5 was shut down.”

The disaster gave scientists a way to develop monitoring tools, improving their ability to predict eruptions and save lives.

Scientists expect Mount St. Helens to probably erupt again this century.

In the last few decades, satellite technology has improved dramatically, helping scientists detect movements in the earth.

A team of researchers started an imaging experiment last year to determine how magma gets to the surface.

A United States Geological Survey study shows Washington has four high threat volcanoes.

The only state with more is Alaska, which has five.

Mount St. Helens has the second highest overall threat level of any volcano studied.

Mount Rainier comes right behind it, then Glacier Peak and Mount Baker.

The study scored a volcano's threat factor based on factors such as the size of the volcano and population density around it.

Mount St. Helens 40th anniversary events Monday

Washington State Parks and the Mount St. Helens Institute are holding events online, which people can visit virtually.

10 a.m. - STEM in 30: Mission Debrief about volcanoes. Join the conversation with the Smithsonian’s National Museum of Natural History’s Global Volcanism program. Watch on Facebook Live on the National Air and Space Museum, Smithsonian Institution and STEM in 30 Facebook pages.

11:30 a.m. to 12:30 p.m. – Washington Emergency Management: Brian Terbush, volcano program preparedness coordinator, answers your questions about Mt. St. Helens and our state’s five active volcanoes using Facebook Live.

2 p.m. – A ranger will give a short talk about May 18th on and its legacy followed by a Q&A session on Facebook.

6-8:30 p.m. – Mount St. Helens virtual story hour. Washington State Parks hosts a live event with a special 40th Eruption Anniversary program.

6:30 p.m. – Northwest scientists present a review of Cascadia tectonics, volcanoes, hazards, and a summary of how the science and monitoring has evolved. The event will be live on YouTube and Facebook.

Take a look at KIRO 7′s past coverage below.

VIDEO: Volcano! Mt. St. Helens (1980 KIRO 7 special)
VIDEO: A look back at Mt. St. Helens eruption (1995)
VIDEO: Essex Porter on Mt. St. Helens
WATCH IT: Survivors, Victims' Families Visit Mt. St. Helens On 30th Eruption Anniversary
UNCUT: 911 Call From Mount St. Helens