Big fluffy snowflakes began falling Tuesday afternoon, with more than 30 centimeters (12 inches) accumulated on the ground by the next morning and more on the way, according to weather forecasts.
A winter storm warning was in place for much of the region and travel was not advised.
Nearly 250 flights have been canceled in Montreal since Tuesday, while travelers described disruptions at the country's biggest airport in Toronto -- where flight cancelations topped 400 -- as a nightmare.
In Ottawa, residents sweated under knit hats and heavy parkas trying to dig out. The odd commuter on skis was spotted headed to work. Others wore snowshoes.
Public broadcaster CBC Radio started reporting the near-record dump in height of dog breeds -- from a Beagle to a Great Dane -- and invited kids to call in to share their "snow day" stories after scheduled guests canceled.
Ice sculptures for the city's annual Winterlude festival, meanwhile, were wrapped to protect them from snow, ice pellets, possible freezing rain and strong winds.
In Toronto, administrators took the rare step of closing all schools and authorities reported more than 60 road accidents and a few power outages, while in Montreal, kids turned icy stairs outside their homes into toboggan runs.
Environment Canada weatherman Simon Legault noted that Montreal was expected to get a whopping 40 centimeters (16 inches) of snow over two days, or one-fifth of the amount that would normally fall on the city all winter.
"It's been a sawtooth winter," he said, describing big and frequent swings in temperatures from -40 Celsius (-40 Fahrenheit) to above freezing, and the reverse, in a matter of hours.
"There's been a lot more snow than usual too," he added. For winter sports enthusiasts, it was a heyday.
The Rideau Canal skateway -- the longest in the world -- was also open but ice conditions were listed as only "fair due to light snow cover."
Officials warned skaters to watch for cracks and rough ice hidden beneath the snow.
And Quebec's Mont Tremblant ski resort said business was brisk, with many people taking advantage of school and office closures to hit the slopes.
(This story has not been edited by Business Standard staff and is auto-generated from a syndicated feed.)