The latest fall storm has cancelled some B.C. ferries sailings and knocked out power to thousands on Vancouver Island, while Washington state has declared a state of emergency.

Environment Canada issued a wind warning, forecasting winds up to 90 km/h could hit parts of the South Coast today before easing this afternoon and evening. By 8 a.m. gusts of 110 km/h had already been recorded on Trial Island near Victoria.

The high winds forced B.C. Ferries to cancel some morning sailings between Nanaimo and Horseshoe Bay in West Vancouver, between Comox and Powell River, and between Denman and Hornby islands.

The B.C. River Forecast Centre also has high streamflow advisories in place for the Cowichan River and Somass River on Southern Vancouver Island.

State of emergency in Washington state

South of the border Washington state declared a level 3 state of emergency on Wednesday after high winds and more than a week of heavy storms caused widespread power outages and flooding.

The latest storm has also triggered rock slides, washouts and numerous road closures, including sections of the I5 interstate route.

Washington transportation officials said interstate highway travel between Portland and Seattle would be closed until at least Thursday morning, as engineers needed to evaluate an unstable hillside after boulders fell onto the freeway north of Portland.

Outside Tacoma, Washington, emergency officials rescued several people who were swept into the swollen Puyallup River overnight on Wednesday from a bankside homeless encampment, police said.

The latest storm has also caused significant damage in Oregon state, where a woman was killed in her bed early on Wednesday after a tree crashed through the roof of her home.

Portland has endured more than 130 millimetres of rain in three days, nearly as much as falls in all of December in a typical year, and Seattle exceeded its normal December rainfall tally in just eight days, while some mountainous areas of both states have received more than 300 millimetres of rain.

With files from Reuters