Many Maritimers can expect power outages or flooding as the Atlantic season's first named storm approaches Atlantic Canada, bringing heavy rain and high winds.

Arthur was downgraded to a Category 1 hurricane Friday morning. The hurricane swiped the U.S. coast early Friday with winds of up to 136 km/h.

Storm Centre: Cancellations in the Maritimes

The storm was about 530 kilometres southwest of Massachusetts by midday. It sped up and was travelling northeast at 40 km/h, the Canadian Hurricane Centre announced at a briefing at 1 p.m. AT.

The storm will certainly be felt in Atlantic Canada. Warnings are in effect for all of Nova Scotia and P.E.I., as well as most of New Brunswick and the Port aux Basques region of Newfoundland.

Fishermen in Nova Scotia secure their boats in anticipation of the storm. (CBC_Craig/Twitter)

The eye of the storm is expected to reach southwestern Nova Scotia at about 9 a.m. Saturday. This means New Brunswick could see the heaviest rains, while Nova Scotia could see the highest winds.

New Brunswick

Chris Fogarty, with the Canadian Hurricane Centre, said much of New Brunswick could get 50 to 100 mm of rain, with some areas getting close to 150 mm in a matter of hours.

"There will inevitably be some flooding," he said.

The situation is reminiscent of 2008, when a storm called Hanna swept into the Maritimes and up the Bay of Fundy, dumping nearly 150 mm of rain on Saint John, N.B. Parts of the city experienced severe flooding.

Nova Scotia

In Nova Scotia, the strongest winds are expected in southwestern sections of the province. Gusts of 90 km/h are expected, while some exposed coastal areas could see gusts as high as 120 km/h, Environment Canada said.

Forecasters say it won't be anything like Hurricane Juan, the Category 1 storm that wreaked havoc in 2003.

"But hurricane-force gusts will make a mess," said Fogarty.

With high winds, there is a risk that objects can be blown around, causing damage or injury.

"Damage to buildings, such as to roof shingles and windows, may occur. Gusty winds can damage soft shelters, tents and awnings at outdoor events. High winds may toss loose objects or cause tree branches to break," said Environment Canada in a weather statement.

People in Halifax can expect the worst midday Saturday.

P.E.I.

P.E.I. is also under a high wind warning. Forecasters say they've been in contact with organizers of a big event in Cavendish to keep them up-to-date on the situation.

"We'll see if the organizers take that information," Fogarty said, adding, "It's going to be a pretty nasty day over there."

Environment Canada is considering adding rainfall warnings for western P.E.I.

"The rainfall rates are of particular concern since they could exceed 15 millimetres per hour during a period of several hours. These conditions could lead to local flooding of small rivers and creeks and possible road washouts," Environment Canada said in a statement.

Fishermen at the government wharf in Sambro, N.S., have doubled up lines to try to secure their boats. (Craig Paisley/CBC)

Newfoundland

Meteorologist Bob Robichaud said the impact on Newfoundland won't be as extensive as in Nova Scotia.

"We do expect some gusty winds up the west coast, but that shouldn't extend too far eastwards," Robichaud said, adding that fishing operations could be affected.

Fishermen and boat owners across the Maritimes are preparing for the storm, battening down the hatches and tying extra lines to wharves to keep their vessels from coming loose in the storm.

Canadian Coast Guard Cmdr. Greg Peters says with waves expected to reach heights of about eight metres, people should stay a safe distance from the shore.

“We are, sometimes, a little bit concerned about people on the shoreline with the storm surge coming and that’s always a danger in certain areas like Lawrencetown Beach and Peggys Cove. But, for the most part, we’re hoping that people have taken heed to the warnings and it’ll be a non-event," he said.

Cancellations roll in

Hurricane Arthur has the potential to disrupt travel for thousands this weekend.

Air Canada has waived the fees associated with changing reservations for anyone whose destination is affected by the storm.

WestJet 's policy is to waive the fees as well, if a tropical storm or hurricane advisory is issued for the destination.

Marine Atlantic hasn't altered its schedule yet. But if customers wish to make adjustments to their travel plans, change fees will be waived, the company said in an email to CBC News.

Several weekend events in Nova Scotia have already been cancelled or postponed in anticipation of Arthur's landfall.

All provincial parks are closed until Sunday, including beaches and campsites.

Mud Hero, an obstacle racing event at Ski Martock approximately 60 kilometres northwest of Halifax, has cancelled its Saturday event and is requesting all its competitors to arrive on Sunday.

"In addition to always providing you with the best and muddiest day ever, your safety is of utmost importance to us," organizers wrote on its website.

Earlier this week, the Stan Rogers Folk Festival in Canso, N.S., cancelled its annual event because of Arthur's approach. Organizers said it was "impossible" to guarantee public safety in those circumstances and apologized for the "horrible decision" they had to make.

Some of the international musicians set to perform at Stanfest will instead perform at two impromptu concerts in P.E.I., with all the proceeds going toward the artists' expenses. Islanders have offered up their homes to use as accommodation.

Early start

This is an unusually early start to hurricane season in Atlantic Canada. Usually, powerful storms hit in the late summer and fall.

Chris Fogarty said he can't be certain what this storm means for the rest of the season.

"This could be the only storm we get this season," he said.