Alaska’s Redoubt Volcano is erupting explosively for a fifth time since 10:38 p.m. local time Sunday evening (2:38 a.m. Eastern time).
The U.S. Geological Survey’s Alaska Volcano Observatory estimates the initial explosion sent ash up to 50,000 feet in the air. The ash appears to be heading north away from Anchorage.
Alaska Airlines has canceled flights, according to the Associated Press.
Redoubt Volcano last erupted over a four-month period from 1989-1990. It began showing signs of unrest earlier this year, and the USGS first warned of a potential eruption in January. The alert level has wavered between yellow and orange since then.
The level of seismicity increased dramatically on March 20, a sign of a potential impending eruption. The seiemicity increased further two hours before the first eruption Sunday evening.
USGS geophysicist John Power said the current eruption could last for weeks or months.