"[10] Scientists said that the volcano "could be working toward a massive eruption that could affect air travel but was not expected to threaten any of the towns in the area.

[5] The volcano erupted again on May 13, 2013,[2] but activity had greatly diminished by July 3, 2013, and on August 8, 2013, the Current Volcano Alert Level was reduced to NORMAL and the Current Aviation Color Code reduced to GREEN.

On June 2 seismic activity intensified and officials raised the alert level from "Watch" to "Warning" and the aviation color code from "Orange" to "Red" after pilots in the area reported an ash plume that reached as high as 22,000 feet above sea level.

[11][12] A new eruption began on March 27, 2016, sending an ash cloud to 37,000 feet above sea level, extending 400 miles NE.

"[16] The straightforward nature of the climb suggests that an earlier unrecorded ascent may have occurred.