Scientists believe that a nearby volcano will erupt, and hundreds of thousands of Americans are preparing for the worst.

Although there are 169 volcanoes classified as “active” in the 50 states of the United States, Alaska’s 11,070-foot-tall Mount Spurr, which is located near Anchorage, the state’s largest city, appears to be poised to erupt.

On a clear day, Alaskans living 81 miles away in the coastal city may see the volcano, which is just under 2,000 feet taller than the Yellowstone supervolcano.

More than 100 earthquakes have occurred beneath Mount Spurr every week between February and March, according to a report by the Alaska Volcano Observatory (AVO), the regulatory agency that regularly monitors 90 of the 140 volcanoes thought to be located on the state.