An Alaska volcano which has been slowly erupting for the past several weeks found new vigor on Tuesday, throwing ash and glowing cinders 5 miles into the sky.

Pavlof Volcano–located almost 600 miles southwest of Anchorage–erupted with such force yesterday that planes had to change their flight paths to avoid the ash cloud, and some flights were canceled altogether. Volcano ash has been found as far as 30 miles away, authorities said. Pavlof has been one of the most active volcanoes in the U.S. since the early ’80s, though it laid dormant from 1996 to 2007.

Interestingly, another volcano located on an Alaskan peninsula–Veniaminof–is also erupting, although scientists say the threat is contained to the areas at the base of the mountain, and a third volcano in the area is also active, though no eruptions have been reported.

It’s been a busy year for active volcanoes; just last week, Popocatepetl erupted in Mexico, spewing ash as far as 40 miles away. Residents weren’t evacuated but had been on standby since mid-May, when a large eruption caused two earthquakes.

Also in May, Mt. Mayon in the Philippines erupted violently, killing five climbers and injuring at least eight after chunks of rock the “size of a living room” were rained down from the summit.