Dorian made landfall as a post-tropical cyclone at 7:15 p.m. ADT southwest of Halifax, according to Environment Canada.
The storm has brought sustained winds of 148 km/h, the agency said.
Nova Scotia saw hundreds of thousands of people left without power as wind and rain lashed the province.
WATCH: Hurricane Dorian: Video captures moment crane collapses in downtown Halifax during storm
“There have been countless reports of downed or uprooted trees, a large construction crane has collapsed in downtown Halifax, and storm surge flooding in several Atlantic coastal areas including Halifax Harbour, and along eastern coastlines in New Brunswick,” an update from the Canadian Hurricane Centre said.
As Dorian plowed into Prince Edward Island, about 50,000 homes and businesses were soon without power, as were another 74,000 in New Brunswick.
Nova Scotia Power CEO Karen Hutt said at a press conference on Sunday that it may be days before power is restored to all customers.
Nova Scotia officials said there have not been any fatalities in the province associated with the storm.
According to a 6 a.m. update from the Canadian Hurricane Centre, the centre of Dorian — now a post-tropical cyclone — is currently located over the Gulf of St. Lawrence, northeast of the Magdalen islands.
“Dorian will continue to track northeastward across the Gulf of St. Lawrence this morning with powerful winds and heavy rainfall,” the update reads. “
Early Sunday morning the west coast of Newfoundland and Labrador was bracing for heavy rain, strong winds, storm surges and large waves, however, Newfoundland Power said it was ready for the storm and would provide updates through an automated alert system.
However, according to Global News chief meteorologist Anthony Farnell, the storm is weakening.
“Dorian, finally after those five landfalls and all of the destruction, is finally weakening and moving out into the Atlantic,” he said.
In a tweet posted Saturday morning, Prime Minister Justin Trudeau urged residents on the east coast to listen to local officials and “stay safe.”
“To everyone in Atlantic Canada bracing for Hurricane Dorian: we’re thinking of you and monitoring the situation closely,” he wrote.
WATCH: Hurricane Dorian: Crane lies on building, street after collapsing during storm
Saturday afternoon, Public Safety Minister Ralph Goodale tweeted, saying Nova Scotia had requested the help of the Canadian government.
“The Government of Canada’s response is of course YES!” Goodale wrote. “The Canadian Armed Forces are mobilizing to deploy to assist with the recovery.”
Up to 700 Canadian Forces personnel will be fanning out across the Maritimes on Sunday to help restore electricity, clear roadways and evacuate residents in flooded areas following the wrath of Dorian.
WATCH: Clean-up crews restoring Halifax after Hurricane Dorian rips through
The monster hurricane first made landfall nearly a week ago in the Bahamas as a much stronger Category 5 storm.
A weakened version of the storm moved off the coast of the U.S. earlier this week, leaving Florida and Georgia relatively unscathed, but causing power outages and flooding in the Carolinas.
-With files from The Canadian Press
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