(NEXSTAR) – A tsunami advisory has been issued for parts of Alaska, California, Hawaii, Oregon and Washington after an undersea volcano erupted in the Tonga Islands.

The National Tsunami Warning Center, a division of the National Oceanic and Atmospheric Administration (NOAA), added that “some impacts are expected” along the West Coast of the United States.

The Pacific Tsunami Warning Center, also operated by the NOAA, had issued its own advisory for the state of Hawaii, warning that waves may be a hazard to swimmers, boaters, or anyone near the shore.

Specifically, the National Tsunami Warning Center issued the advisory for the following areas:

  • The coast of the California/Mexico border to the Oregon/California border, including San Francisco Bay
  • The coast of Oregon, from the California/Oregon border to the Washington/Oregon border, including the Columbia River estuary coast
  • The outer coast of Washington from the Oregon/Washington border to Slip Point, Columbia River estuary coast, and the Juan de Fuca Strait coast
  • In British Columbia, from the north coast and Haida Gwaii, the central coast and northeast Vancouver Island, the outer west coast of Vancouver Island, the Juan de Fuca Strait coast
  • In Southeast Alaska, including the inner and outer coast from the British Columbia/Alaska border to Cape Fairweather
  • In South Alaska and the Alaska Peninsula, including the Pacific coasts from Cape Fairweather to Unimak Pass
  • The Aleutian Islands , Unimak Pass to Attu, including the Pribilof Islands

More detailed maps can be found at the NOAA’s Tsunami Warning System website.

Tsunami activity was expected to begin as early as 6 a.m. in parts of Alaska, 7:35 a.m. in parts of California, 7:55 a.m. in parts of Oregon, 8:30 a.m. in parts of British Columbia, and 8:35 a.m. in parts of Washington.

The tsunami, caused by an undersea volcano located about 40 miles from Tonga’s capital and visible from space, sent waves crashing across Tonga’s shorelines, the Associated Press reported on Saturday morning. There were no immediate reports of injuries.