12/29/2017 06:29 EST | Updated 12/29/2017 06:40 EST

Freezing rain, snow, cold grip much of B.C.; Boy missing after crash into lake

VANCOUVER — An underwater search is underway for 10-year-old British Columbia boy missing after the car he was in veered into Arrow Lake near Nakusp during snowy, icy weather.

RCMP say a 37-year-old man and an 11-year-old girl were able to get out of the Toyota Matrix before it sank, but an underwater recovery team is searching for the missing Slocan-area youngster.

The crash was one of many on southern B.C. highways since Wednesday when a series of storms brought snowfall, freezing rain and extreme cold to the southern Interior and some northern regions. 

Travel advisories are posted for the entire Coquihalla Highway and heavy snow is also forecast for Highway 97C between Merritt and Kelowna, with Environment Canada calling for as much as 25 centimetres in mountain passes before Saturday.

One of the hardest hit areas is the Fraser Valley where freezing rain and a buildup of ice brought down trees and power lines Thursday night, knocking out electricity to thousands.

An extreme cold alert also remains in effect for Yoho and Kootenay parks and northern B.C., including the Peace River region, North Coast and the South Klondike Highway where the weather office says temperatures feel as low as -45 C with the wind chill.