Hurricane Bill was downgraded to a mere storm on Monday as it swept over Canada's easternmost province of Newfoundland, but it was still packing a mighty punch, the US National Hurricane Center said.

"Bill loses tropical characteristics," declared the Miami-based center just hours after the first hurricane of the Atlantic season made landfall on the southeastern edge of Newfoundland island.

As of 0900 GMT, it said, Bill was packing maximum sustained winds of 70 miles (110 kilometers) an hour as it swirled 190 miles (305 kilometers) northeast of Cape Race, Newfoundland -- below hurricane status requirements of at least 74 miles (119 kilometers) an hour.

The NHC said it was now charging north-northeast at 43 miles (69 kilometers) an hour. Further gradual weakening of Bill was forecast for the next couple of days.

But the center warned that "even though Bill is no longer a tropical cyclone, it is expected to produce a large area of storm and gale-force winds over the North Atlantic during the next day or two."

The NHC said that since Bill did not qualify as a tropical storm any longer, it will discontinue its public advisories about the event.

For meteorologists, a hurricane is said to lose its tropical characteristics when it moves over land or cooler water -- unable to draw on warm water to feed its awesome energy.

Earlier in the morning, Bill passed over the southeastern part of Newfoundland, but there were no immediate reports of any casualties or damage there.

But it left behind damage in the Canadian province of Nova Scotia where strong winds and rain knocked out power to 32,000 customers.

Some roads in Nova Scotia were closed and more than a dozen flights from Halifax airport were cancelled Sunday as the storm passed through. Ferry services between Nova Scotia and Newfoundland were suspended as well.

In the United States, a seven-year-old girl was killed Sunday when a rogue wave swept a group of sightseers into the ocean from a cliff-top overlook in the northeastern state of Maine, a US Coast Guard spokesman said.

The girl, who was not identified, was with about 20 other tourists on a scenic overlook in Acadia National Park known as Thunder Hole when the huge wave struck, the spokesman said.

"She was recovered, but the hospital reported to us that she was deceased upon arriving to the hospital," Petty Officer James Rhodes told AFP. The precise cause of death was not immediately known.

Earlier, as Bill moved along the US east coast, tropical storm warnings were put in place, including on the island of Martha's Vineyard, where President Barack Obama and his family arrived for a vacation once Bill churned by.

The storm had raised concerns and the Obamas decided to slightly delay their planned Sunday morning departure to Martha's Vineyard.

By Sunday afternoon, the storm warnings were lifted and the Obamas touched down safely at their holiday destination.

The Atlantic hurricane season began on June 1 and ends on November 30.

Bill's progress follows one of the calmest starts to the hurricane season in a decade, which researchers for the state of Colorado attributed to the development of an El Nino effect in the Pacific.