By Daniel Trotta and Chris Prentice

NEW YORK (Reuters) – Atlantic storm Hermine, which has killed two people, lurked off the middle of the U.S. East Coast late on Sunday while threatening to regain hurricane strength, after having spared the region the brunt of its wind, rain and tidal surge.

Forecasters warned swimmers and boaters to avoid the risk of deadly surf churned up by the storm and stay out of treacherous waters during the Labor Day holiday weekend, when many Americans celebrate the end of summer.

Hermine was still packing maximum sustained surface winds of nearly 70 mph (113 kph) late on Sunday, and forecasters said it  could intensify slightly to reach hurricane strength again, before it starts to dwindle later on Monday.

But for now, its strongest winds were extending outward by about 230 miles (370 km), failing to reach U.S. shores.

Hermine was forecast to bring up to 2 inches (5 cm) of rain to southern New England on Monday, after having hit land in Florida on Friday, and churning up the southeastern seaboard.

Then it merged with a conventional weather front, to be reclassified on Saturday as a post-tropical cyclone.

But Hermine was not expected to make landfall again, said Robbie Berg, an official of the National Hurricane Center.

A tropical storm warning remained in effect Sunday night from the Delaware and New Jersey shores north to New York’s Long Island and beyond to Martha’s Vineyard and Nantucket Island off Massachusetts, but was canceled for New York City, which Berg said appeared largely out of harm’s way.

Potential storm-surge inundation levels of no more than 1 to 3 feet (30 cm to 1 m) were expected in coastal areas.

As the threat to New Jersey waned, Governor Chris Christie ordered Island Beach State Park reopened for Monday, while warning that lingering rip currents and rough surf might still make the ocean unsafe for swimmers.

At 11 p.m. EDT on Sunday, Hermine’s center was about 325 miles (523 km) southeast of Long Island, the eastern tip of New York, the hurricane center said.

It was expected to “meander slowly” off the mid-Atlantic region, moving north-northeast at only 3 mph (5 kph) and stay at least 300 miles (480 km) from shore before beginning to weaken by Monday night, the agency said.

WANING STORM THREAT BEYOND COAST

The storm claimed at least two lives, in Florida and North Carolina, but the widespread power outages and flooding that battered Florida, Georgia and the Carolinas had yet to materialize farther north, where alarming news reports scared many tourists away from the beach on Sunday.

Those who stayed awoke to sunshine, but stronger-than-usual winds and choppy seas.

“It was a little overhyped by the media,” said Andrew Thulin, assistant general manager of Daddy O Hotel Restaurant in the New Jersey township of Long Beach.

“It killed the weekend for everybody down here.”

Officials mindful of the 2012 devastation of Superstorm Sandy took every precaution. Elsewhere in the state coastal roads were reported flooded, and beaches engulfed by the sea.

Hermine became the first hurricane to make landfall in Florida in 11 years, packing winds of 80 mph (129 kph), and knocking out power to 300,000 homes and businesses. Downgraded to a tropical storm within hours, it still packed a wallop.

(Additional reporting by Steve Gorman from Los Angeles and Chris Michaud from New York)