Weather reports predict the hurricane will have downgraded to post-tropical storm status by the time it hits land.
In Montreal, the post-tropical storm should bring about 20 to 40 millimetres of rain between Monday afternoon and Tuesday night.
André Cantin, a meteorologist for Environment Canada, says the biggest problem will be strong winds.
"In some places, we might get gusts close to 90 km/h, especially along the Saint-Lawrence River between Quebec City and Montreal," he said.
Hydro-Québec says it plans to send 25 teams of workers to Vermont to help with the storm aftermath. The hydro company said the teams would be close enough to Quebec, in case their work is needed once Sandy pushes through.
Environment Canada recommends that people secure any piece of outdoor furniture that could easily get blown away by the wind.
The Canadian Red Cross has issued a warning for Ontario, telling people to stock up on at least three days' worth of supplies in case the storm's impact affects the province.
Blackouts and flooding could affect many parts of Ontario, according to Environment Canada.
Evacuations are also possible due to the system, which has earned the moniker "Frankenstorm" — a reference to the collision between Sandy and the ongoing severe weather above central Canada.