Alaska's Mt. Redoubt Volcano Erupts Again

March 26, 2009 -- Alaska's Mount Redoubt erupted twice Thursday, spewing a more than 12-mile-high cloud that could drop ash on Anchorage for the first time since the volcano began erupting Sunday night.

The Alaska Volcano Observatory said the first eruption about 8:30 a.m. shot an ash cloud about 30,000 feet in the air, and the second eruption about an hour later sent ash 65,000 feet high -- the highest cloud since the eruptions began. The larger eruption caused a mud flow into the Drift River near the base of the volcano.

Before Thursday's eruptions the volcano had been relatively quiet for more than a day.

According to the National Weather Service, prevailing winds are expected to carry ash from the larger eruption east across Cook Inlet toward some of Alaska's larger communities. An ash fall advisory for the western Kenai Peninsula covers the towns of Kenai, Soldotna and Cooper Landing.

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Anchorage spokeswoman Jenny Evans said the state's largest city, roughly 100 miles northeast of the volcano, could see trace amounts of ash.

The smaller cloud was expected to drop minor amounts of ash on Homer, a tourist and fishing town at the southern tip of the Kenai Peninsula.

Ash poses a significant threat to aircraft engines, and a small carrier, Era Aviation, canceled four flights as of midday. Alaska Airlines, which unlike Era does not serve the Kenai Peninsula, canceled one flight; earlier in the week it had canceled 35.

The National Weather Service also issued a flash flood warning for the Drift River, near the volcano. Eruptions can cause snow and ice to melt on the mountain, resulting in flooding along the river that drains from the mountain.

Research geologists with the U.S. Geological Survey have said a lot of snow and ice remains on the mountain, increasing the danger from mud flows that already have downed hundreds of trees and carved a huge gouge out of a glacier.