Tens of thousands remain without power and large swaths of highway in northern Ontario are closed after blasts of heavy snow, freezing rain and strong winds hit a swath of the province.
The Hydro One outage map shows roughly 20,000 customers were in the dark as of late Monday, down from about 61,000 earlier in the day.
The province's largest electric utility says the outages were due to the storm that had knocked down lines from ice accumulation on tree branches.
The wintry conditions are causing major travel disruptions in the north, with Ontario 511, the province's road information service, reporting closures for hundreds of kilometres along Highway 11 between North Bay and Hearst.
Environment Canada says most of Ontario could expect a mixed bag of precipitation Monday, ranging from freezing rain in Ottawa to heavy snow along Lake Superior and up to 60 centimetres in Timmins.
The weather agency says strong wind gusts of up to 90 kilometres per hour were expected in the Greater Toronto Area and southwestern Ontario.
Hydro One says since the storm began Sunday, crews have restored power to tens of thousands of customers, but challenging road conditions continue to delay crew access.
Multiple stretches of highways in the Timmins area and other parts of northern Ontario were closed Monday morning as the winter storm battered the region.