May 18, 1980 Eruption of St. Helens
St. Helens in the United States erupted on May 18, 1980 with a Volcanic Explosivity Index of 5. The eruption killed 61 people, counting its secondary effects. It caused a tsunami.
Where it erupted
St. Helens, United States, with its other significant eruptions.
The eruption
- Date
- May 18, 1980
- Volcano
- St. Helens, stratovolcano
- Country
- United States
- Volcanic Explosivity Index
- 5, very large (eruption column over 25 km)
- Killed by
- Pyroclastic flows, surges and direct blasts; Mudflows and lahars; Tephra (ash, bombs, lapilli, steam blasts)
- Tsunami
- Yes: the tsunami it caused
- Earthquake
- Yes: the earthquake with it
- Location
- 46.200° N, 122.180° W
The toll
- Deaths
- 57; 61 with the tsunamis, mudflows and other effects it caused
- Damage
- $2 billion
Where the literature gives no number, NCEI records a description on a scale of 1 to 4, printed here in its words. Damage is in millions of US dollars of the year of the event, not adjusted for inflation.
What the record says
NCEI’s account, from the sources it cites.
All known direct deaths were attributable to the lateral blast, ashfall, and lahars of the May 18 eruption. Among the 25 victims who were autopsied, asphyxiation by airway constriction with ash was the cause of death in 17 and contributory in 2 others with thermal injuries. Thermal injuries alone accounted for 3 deaths; three victims died of trauma. A pilot of a crop duster was killed when his plane hit powerlines in central Washington State during tephra fall. In Yakima, a traffic accident, attributed to poor visibility, resulted in 1 death and 2 elderly people with heart conditions died while shovelling tephra from their property. Almost certainly, other indirect deaths also occurred. (reference #9675)
90 deaths, 2500 affected, $860 million damage. (reference #1250)
Other significant eruptions of St. Helens
More
Every eruption in 1980The 1900sSt. HelensEarthquakes near St. HelensThis day in weather history
Sources
Volcanoes and significant eruptions from NOAA’s National Centers for Environmental Information, Global Historical Hazard Database, cited as NCEI/WDS, doi:10.7289/V5PN93H7. Public domain. Read 2026-09-24. Volcano numbers are the Smithsonian Institution’s Global Volcanism Program’s. NCEI event 3314.