Ash Cloud Over Mount St. Helens Conjures Memories of 1980 Disaster

U.S.|Ash Cloud Over Mount St. Helens Conjures Memories of 1980 Disaster

On the morning of May 18, 1980, the most destructive volcanic eruption in United States history killed 57 people in Washington State. The enormous column of ash that was unleashed by Mount St. Helens has been emblazoned for decades in the minds of locals who survived the catastrophe.

This week, history seemed to be repeating itself.

On Tuesday, gray clouds shrouded the jagged peak of Mount St. Helens, which remains an active volcano between Portland, Ore., and Seattle, and the clouds were opaque enough that commercial pilots reported difficulty navigating through them. Photographs showed the mountain’s crater disappearing behind the haze.

But, luckily, it wasn’t another volcanic eruption.

Strong winds whipped the Cascade Range on Tuesday and kicked up loose volcanic ash from the multiple eruptions in 1980 and lofted it into the air, according to the U.S. Geological Survey. The whirling cloud of dust was lofted thousands of feet into the air.

Snow typically blankets much of Mount St. Helens, but once that snow melts away by late summer, the 1980 ash that lingers on the surface of the mountain becomes exposed, said Noah Alviz, a meteorologist at the National Weather Service office in Portland. When high winds kick up, the ash can become suspended in the air, he said.

Easterly winds are common at this time of year, but Mr. Alviz said the winds on Tuesday, with gusts of over 50 miles per hour, may have been stronger than usual. Winds are caused by differences in atmospheric pressure, and the winds on Tuesday were traveling from an area of high pressure over Eastern Oregon to low pressure over Western Oregon.

Employees at several local businesses said on Wednesday that they were not concerned by the ash cloud, which seemed to be mostly observed by those traveling in the air. But the phenomenon had enough potential for alarm that the U.S. Geological Survey explained it on Tuesday as the loose volcanic ash from 1980.

Adam Batz, a meteorologist with the National Weather Service in Portland, estimated that these localized dust storms form over Mount St. Helens every few years. A plume of ash towered above the mountain in 2020 during an outbreak of wind-driven wildfires that also sent smoke into the air.

The Weather Service Unit in Seattle, which provides forecasting for air traffic controllers, issued an advisory on Tuesday warning of ash up to 10,000 feet in the atmosphere.

While Tuesday’s cloud was striking, it was nothing like the massive 80,000-foot-tall ash column in 1980. That explosion of volcanic material was enough to block the sun, damage sewers and clog waterways.