Police in eastern Newfoundland advised motorists Wednesday to stay off highways and smaller roads, as a winter storm moved quickly over the island.

RCMP said drivers should avoid the Trans-Canada Highway between St. John's and the Salmonier Line, and said visibility was poor on regional highways on the Avalon Peninsula.

Police also issued advisories to exercise caution elsewhere in the province, as the storm — which is including a variety of snow, high winds and freezing rain — eliminated visibility in some areas.

Cpl. Henry Poswiata, of the RCMP's traffic services division, said the highway between Port aux Basques and Stephenville was already snow covered by late morning.

"The storm has started and it's going to head across the province, so if you don't have to go on the highway, my suggestion is to stay put," Poswiata told CBC News.

In Labrador, the weather has ranged from extreme cold in some areas to blizzard forecasts in others.

Dozens of schools across the province closed for the day, as did some public services and events.

"It is greasy, it is slick, it is slow going," said CBC reporter Cecil Haire, describing conditions in and around St. John's.

The Eastern School District pre-emptively closed all schools in metro St. John's hours before the first snowflakes fell, anticipating how a storm might have posed safety risks.

At the time, conditions were crystal-clear in the St. John's area. Albert Trask, assistant director of education for the Eastern School District, said the board made the call early Wednesday morning after consulting with Amec, a private weather forecaster.

'No guarantee' buses safe on slick roads

Trask said safety was the board's primary concern, particularly for the early afternoon, when the storm is expected to hit full stride around the time classes would be dismissed.

"There's no guarantee that [there will] be safe conditions to put children on buses, to get them home from school," Trask told CBC News on Wednesday morning.

Environment Canada issued weather warnings for much of Newfoundland and Labrador for the day, ranging from wind and blowing snow warnings in eastern Newfoundland to wind chill and blizzard warnings in Labrador.

Marine Atlantic ferries are on hold in Port aux Basques and North Sydney. The ferry connecting Newfoundland with southern Labrador is also docked for the day.

At St. John's International Airport, several flights were delayed or cancelled Wednesday morning. Officials said more could follow as the system moved through.