VANCOUVER -- Dozens of BC Ferries sailings have been cancelled ahead of a windstorm expected to slam the South Coast Tuesday afternoon.

BC Ferries issued a travel advisory Monday evening, calling the incoming storm an "extreme weather system."

While the 7 and 9 a.m. sailings between Tsawwassen and Swartz Bay are scheduled to go ahead Tuesday, the remainder of late morning and afternoon sailings have been cancelled.

BC Ferries is hoping to resume service on the route in both directions at 7 p.m.

There are also significant cancellations between Horseshoe Bay and Departure Bay, with the last morning sailings expected at 8:25 a.m. Sailings on that route aren’t expected to resume until 8:45 p.m. from Departure Bay and at 10:10 p.m. from Horseshoe Bay.

A full list of service notices can be found online.

Deborah Marshall with B.C. Ferries says the decision to pre-emptively cancel many of the sailings was made Monday night in hopes of giving passengers ample notice.

She says sailing in the high winds would be a safety issue.

“It is in the interest of safety," Marshall said. "We can have situations where we can do damage to the vessels while we are docking or undocking and the ride can be extremely uncomfortable for customers during the high wind situations."

Marshall says passenger traffic is still down significantly, with people being encouraged to travel for essential reasons only. She says there was a significant reduction in holiday travel with vehicle traffic down about 60 per cent on major routes, and passenger traffic down about 70 per cent.

The Tsawwassen terminal remained quiet Tuesday, with mostly commercial truck traffic left waiting for sailings to resume. 

Environment Canada has issued a wind warning for Metro Vancouver, including Surrey, Langley, Richmond and Delta.

Winds in some areas near the water could reach 70 km/hour according to Environment Canada.

The wind is expected to pick up around noon before tapering off through the evening.

A rainfall warning is also in effect for some areas of Metro Vancouver.

The North Shore, Coquitlam and Maple Ridge could see up to 60 millimetres of rain by Tuesday night.