Hurricane Dorian is expected to spin into Atlantic Canada this weekend as either a Category 1 hurricane or a strong tropical storm, churning out sustained winds up to 130 km/h, according to the Canadian Hurricane Centre.

"It's probably going to be a big deal," said Environment Canada meteorologist Ian Hubbard.

"It's going to be a very significant wind event. We're a few days away from it, so we still have to work on the details."

Hubbard, who's based in Halifax, said the storm is forecast to track along the U.S. Eastern Seaboard to North Carolina's Cape Hatteras on Friday and move near Nova Scotia on Saturday, then on to Newfoundland and Labrador on Sunday.

What to expect

A Category 1 hurricane produces sustained wind speeds at 119 km/h or above, reaching Category 2 at 154 km/h.

According to the National Hurricane Center in Miami, Category 1 hurricanes can break large tree limbs, pull off shingles and vinyl siding and topple trees with shallow roots. That means widespread power outages are a key concern for emergency planners.

Heavy rainfall is expected, especially north and west of Dorian's track, which means the biggest downpours will likely be along the southern Maritimes on Saturday and parts of Newfoundland on Sunday.

"We want to make sure people are paying attention to our forecasts and basing their decisions on that," said Hubbard. "There is still a lot of uncertainty in [Dorian's] track. We can't pin down exactly where it's going to go at this point."

'There's going to be a lot of wind'

However, Hubbard said it would be a mistake for people in the region to focus on Dorian's precise track, given the fact the storm appears to be expanding.

"The impacts of this storm will reach well beyond the eye or the storm centre," he said. "There's going to be a lot of wind over a lot of areas, regardless of whether you are close to that centre or if you're a couple hundred kilometres away."

Environment Canada says most parts of Atlantic Canada will experience tropical storm force winds, which exceed 63 km/h.

However, Dorian's course and strength could change significantly in the days ahead, especially if it makes landfall in the United States.

The latest computer models indicate Dorian could head out to sea as it moves toward Nova Scotia, or it could shift northward into southern New Brunswick and the eastern edges of Quebec and southern Labrador.

As of Wednesday, the hurricane centre started issuing bulletins every six hours.

The damage so far

As Dorian left behind a trail of destruction in the Bahamas, rescue crews fanned out Wednesday to find survivors amid a landscape of splintered homes and submerged streets.

The official death toll on the islands of Abaco and Grand Bahama stood at seven but was certain to rise as emergency workers had yet to reach some areas.

Though Dorian remained off the Florida shoreline, largely sparing the state, its 165 km/h winds were expected to take a heavier toll on Georgia and the Carolinas on Thursday.

An estimated three million people in the four states were warned to clear out. Highways leading inland were turned into one-way evacuation routes.

As for tropical storm Gabrielle, which developed in the middle of the Atlantic late Tuesday, it poses no immediate threat to Canadian territory, Hubbard said.

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Keep up to date on Hurricane Dorian with the CBC Maritimes live weather blog, updated every day.

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