VANCOUVER - A windstorm lashing B.C.'s south coast has knocked out power to roughly 90,000 people, forced the cancellation of several ferry sailings, and cancelled school for thousands of students.

Environment Canada has issued a wind warning for the region, with winds on Vancouver Island and in the Vancouver area expected to reach up to 100 kilometres an hour in some locations.

The storm has knocked down trees and power lines in many areas, with BC Hydro reporting power outages on Vancouver Island affecting about 70,000 customers.

Another 20,000 customers are without power in the Vancouver area and along the Sunshine Coast.

BC Ferries has been forced to cancel several sailings on major routes between the mainland and Vancouver Island because of the choppy seas caused by the wind.

The power outages and ferry cancellations in the Comox Valley area on Vancouver Island, where the local school district has closed all of its 23 schools, keeping nearly 10,000 students out of class.