Planes Warned to Avoid Airspace Around Erupting Alaska Volcano

(TheBlaze/AP) — The National Weather Service on Saturday warned planes to avoid airspace near an erupting Alaska volcano as it spewed ash 30,000 feet above sea level.

Pavlof Volcano began erupting, pushing lava out from a vent near its summit, on Wednesday. By Friday the ash cloud reached 16,000 feet. The eruption intensified at 6 a.m. Saturday, sending the ash cloud higher, said Dave Schneider, a geophysicist at Alaska Volcano Observatory.

Pavlof Volcano in 'new phase of eruptive activity' on #Alaska Peninsula https://t.co/4NXFCIBpIF (photo/@alaska_avo) pic.twitter.com/V36Gp1PU4O

— KUCB (@KUCBNews) November 13, 2014

It's not clear how long this eruption will last, Schneider said. Pavlof's eruptions may last for weeks or months with varying levels of intensity, he said.

Pavlof — Alaska's most active volcano — is located about 625 miles southwest of Anchorage. It's had more than 40 recorded eruptions, including earlier this year and last year. It also lies along popular international air routes connecting Europe, North America and Asia.

The eruption has had little effect on people on the ground. The closest community, Cold Bay, is 40 miles away. Observers there reported seeing dark snow on the surface of the volcano Wednesday, indicating an eruption had started.

There have been some small avalanches of hot rock down the north flank of the volcano. These may produce local mud flows to the north, but scientists say they would likely be minor.