07/02/2014 07:38 EDT | Updated 09/01/2014 05:59 EDT

Tropical storm Arthur could become hurricane, impact Atlantic Canada

HALIFAX - Environment Canada is warning that tropical storm Arthur could bring some rough weather to Atlantic Canada this weekend.

The Canadian Hurricane Centre in Halifax says the storm is expected to intensify to hurricane strength and accelerate as it moves northeastward along the East Coast of the United States on a track that could take it across Nova Scotia.

However, the storm's course and strength remain difficult to predict, meteorologist Bob Robichaud said Wednesday.

"This far out, there's still about a 300-kilometre margin of error in the forecast track," he said in an interview. "It could be anywhere from southern, central New Brunswick all the way to offshore Nova Scotia at this point. ... (But) it looks like someone will get something from this storm on the weekend."

Robichaud said a trough of low pressure moving eastward from the Great Lakes is expected to have an impact on the advancing storm, which was churning out winds in excess of 100 kilometres per hour as it moved parallel to Florida's coast Wednesday.

"If we get the storm coming up right as the trough is going through, that could accentuate some of the rainfall amounts in the Maritimes," he said. "That's two weather features that we're monitoring closely."

He said the Maritime provinces can expect the storm to be at its worst on Saturday before moving into Newfoundland Sunday.

Despite the uncertainty about Arthur's path, organizers of the annual Stan Rogers Folk Festival in Canso, N.S., have cancelled the music event, which was to start Friday and continue through the weekend.

"It is impossible in these circumstances for us to guarantee public safety," Troy Greencorn, the festival's artistic director, said in a statement. "It’s a horrible decision to have to make after so much work by so many people, but we just aren't prepared to take the risks. ... Hosting an outdoor, camping festival in a hurricane would be foolhardy.”

There was no word on when or if the event will be rescheduled.

Meanwhile, hurricane watches have been issued for parts of North Carolina's coast, while tropical storm watches are in effect for parts of Florida and South Carolina.

American forecasters say the first named storm of the hurricane season was expected to skim North Carolina's Outer Banks on Friday — the July Fourth holiday. The 320-kilometre string of narrow barrier islands are prone to flooding but popular for beachgoers.

Lee Nettles, executive director the Outer Banks Visitors Bureau, emphasized reports that show the storm should move fast, and he said the area sees frequent storms.

"We want everybody to be safe and prepared, but we are not overly concerned at this point," he said.

Tony Saavedra of the U.S. National Weather Service said the storm was expected to lash Cape Hatteras, N.C., with winds in excess of 136 km/h, well above the minimum for a Category 1 hurricane, which is 119 km/h.

On Hilton Head Island, on South Carolina's southern tip, there was little concern about Arthur. The storm was forecast to pass the island on Thursday well out at sea.

"It will be a sold-out weekend," said Charlie Clark, spokeswoman for the Hilton Head Island Chamber of Commerce. "We're not getting calls from visitors asking what's up with this storm."

— With files from The Associated Press