The Alaska Volcano Observatory has downgraded the commercial airliner alert level for a volcano in the Aleutian Islands, a day after a small explosion sent ash 15,000 feet into the air.
Satellite images showed the ash cloud after remote Cleveland Mountain erupted early Thursday.
The observatory said Friday that no new explosive activity has been observed. The threat has been downgraded from orange, representing a minor eruption, to yellow, meaning elevated unrest.
Cleveland Mountain is a 5,675-foot peak on an uninhabited island 940 miles southwest of Anchorage. Scientists have been monitoring volcano activity since July when they detected lava accumulating in a crater at the summit.
Ash clouds exceeding 20,000 feet from Alaska volcanoes are a threat to trans-Pacific air carriers.