Hundreds of thousands of Americans are bracing as scientists warn that Alaska’s Mount Spurr could erupt soon. The 11,070-foot volcano is visible from Anchorage, just 81 miles away, and is taller than the Yellowstone supervolcano. Though 169 volcanoes in the U.S. are labeled “active,” Mount Spurr is drawing special attention now.

The Alaska Volcano Observatory (AVO) monitors 90 of Alaska’s 140 volcanoes and has reported alarming signs. “More than 100 earthquakes had taken place beneath Mount Spurr each week” in February and March. Since April 2022, over 3,400 quakes have been recorded around the volcano.

AVO scientist Matt Haney told Alaska Public Media that an eruption might not be heard in Anchorage, but “those who were near the volcano would be able to hear it. But being that close would not be wise.”

If Mount Spurr erupts, it may produce ash clouds capable of volcanic lightning. “Because volcanic ash particles rub against one another, ash-producing eruptions can create volcanic lightning,” scientists explained.

Given its history of eruptions in 1953 and 1992, and the current seismic activity, experts continue to monitor Mount Spurr closely while warning residents to stay alert.