A warning was issued to airplanes flying over Alaska on Saturday, 15th Nov because Pavlof Volcano in Alaska started spewing ash 30,000 feet above sea level.
The eruption started on Wednesday, when lava was coming out from a vent near the summit of Volcano Pavlof. The ash clouds were about 16,000 feet on Friday and the eruption intensified early Saturday morning, sending the ash cloud higher according to Dave Schneider, a geophysicist at Alaska Volcano Observatory.
So far it is not clear for how long America’s most active Volcano would keep on erupting but usually its eruptions continue for a week or up-to a month depending upon the intensity of eruption.
Sources : Travel Industry Today