Anchorage Daily News

Volcanic ash stranded several thousand travelers Sunday when a shift in the wind moved a giant ash plume into flight routes, causing Alaska Airlines to cancel 41 flights into and out of Alaska.

"The entire state is unflyable," Alaska Airlines staff told passengers at Seattle's airport, according to Chelsea Harms, an Anchorage woman who was booked on flight 111 to Anchorage.

Whether everyone had stopped flying in and out of the state was unclear Sunday night.

An online list of arrivals and departures scheduled at the Anchorage airport showed that only Alaska Airlines had cancelled flights - 28 on Sunday and 13 more this morning.

Flights involving other airlines weren't listed as cancelled, but Alaska Airlines spokeswoman Caroline Boren said she heard Delta and United had cancelled flights too.

Alaska Airlines made the decision to halt flights after the National Weather Service issued a SIGMET (Significant Meteorological Information) warning Sunday afternoon for an area in Southeast Alaska near the Panhandle, Boren said.

"If there's an ash plume in the way, we won't fly," she said.

All those stranded passengers can blame the inconvenience on a shift in the wind.

Kristi Wallace, a research geologist for the Alaska Volcano Observatory, said the wind sheared off part of a 40,000-foot ash plume and carried it northeast from the North Pacific to the middle of the Panhandle. The plume came from Kasatochi, a volcano island in the central Aleutians that erupted Thursday.

Kasatochi is one of three volcanoes currently simmering in the Aleutians, along with Mount Cleveland and Okmok.

Seismic activity at Okmok picked up notably on Sunday, the observatory said, but it was the days-old ash plume created by Kasatochi's initial eruption that created headaches for travelers.

"The flight levels are going right through that SIGMET area, and that area is full of ash," Wallace said. Depending on what happens to the ash cloud overnight, more flights could be cancelled today. Boren said people can check the status of flights today at alaskaair.com, or they can call 1-800-AlaskaAir.