A motorist with snow on their car drives in Richmond, B.C., on Wednesday, Dec. 21, 2022. Warmer weather is set to arrive in parts of British Columbia by Christmas Eve but forecasters warn it's going to get messy. THE CANADIAN PRESS/Darryl Dyck

VANCOUVER - Drivers across much of southern B.C. are being asked to avoid non-essential trips as snow and freezing rain threaten to close highways, knock out power and make travel dangerous.

Environment Canada predicted heavy snow, ice pellets and freezing rain in Metro Vancouver, Vancouver Island and the Fraser Valley starting Thursday night through Christmas Eve, followed by heavy rain as temperatures spike upwards.

The province said freezing rain in the Fraser Valley could last as long as 36 hours.

Transportation and Infrastructure Minister Rob Fleming said travel by road on Vancouver Island, the south coast, or to and from the Interior should be avoided "unless absolutely necessary."

He said the significance of the incoming weather front can't be overstated.

Up to 25 centimetres of snow is expected in parts of the Lower Mainland through Friday night and strong easterly winds could result in near-zero visibility in some parts.

The transition from snow to rain could have a significant impact on road and sidewalk conditions, while ice buildup could lead to tree branches breaking, Environment Canada predicted.

"Rarely do we see such heavy snowfall followed by freezing rain and heavy rainfall. We want everyone to remain safe," Fleming said at a news conference.

Contractors were preparing for heavy snow with more than 100 pieces of equipment, Fleming said, and they would have to manage the "tricky" timing of when to switch to laying down salt to combat the freezing rain.

The ministry may proactively close highways in the interest of safety, Fleming said.

"I know people have plans for the holidays. They want to spend family time with family, friends and loved ones. But this is a significant weather event."

Environment Canada meteorologist Trevor Smith described the upcoming weather as "a clash of the titans" between an arctic air mass that has been keeping things cold and Pacific air that is on its way.

"It's basically that transition from the arctic air to the Pacific air, this battle, that's going to kind of produce all this nasty weather," he said Thursday.

"And eventually the Pacific air will win out by later on Saturday for the most part, so we'll be all-in to rain. But it's that intervening period tonight and Friday where we're going to see all these different precipitation types."

Temperatures that dipped to -12 C in Vancouver on Wednesday are expected to hit 8 C by Saturday and 10 C by Monday, leading to the risk of localized flooding due to a combination of meltwater and snow-blocked drains.

Smith said the river forecast centre is not concerned about major floods from rivers because the snowpack is deep enough in the mountain that it can absorb the rain that's coming on Saturday.

Bowinn Ma, minister of emergency management and climate relations, said BC Hydro was advising that freezing rain was likely to cause power outages, particularly on Vancouver Island and in the Fraser Valley.

"Their crews are ready to respond to outages as quickly as possible. If you need to travel, get prepared by packing a winter survival kit including a windshield scraper, a snow brush, flashlights and extra batteries, first aid supplies, blankets, drinking water and non-perishable foods," she said.

"It is also a good idea to have a full tank of fuel before travelling."

Ma said her ministry would be monitoring the situation and had pre-positioned sandbags and other tools to help with any flooding.

The City of Vancouver is also advising drivers to stay off the roads if they can.

A statement from the city on Thursday said crews had been working 24 hours a day to apply salt and brine treatments while cleaning up significant snow accumulations.

BC Ferries said there was a strong possibility of sailing cancellations on a variety of routes.

“Poor road conditions leading to the terminals as well as high winds are expected to impact operations. BC Ferries will automatically refund customers with bookings if a sailing is cancelled,” a statement said.

This report by The Canadian Press was first published Dec. 22, 2022.

News from © The Canadian Press, 2022