Heavy snowfall has created treacherous driving conditions on the Sea to Sky Highway this weekend.

Squamish RCMP said at least 25 vehicles have gone off the road or into the ditch between Squamish and Whistler.

Variable speed signs have been set to 70 km/h but drivers were warned to stay off the highway altogether if possible.

Drive BC advises motorists to slow down and drive for the conditions, and to ensure winter tires have been installed.

Environment Canada had issued a snowfall warning with 15 centimetres expected on Saturday.

The weather agency forecasts periods of rain on Sunday, which would turn the snow into slush.