People along the Carolina coast braced for approaching Tropical Storm Danny, which reinforced the dangers of even a weakening storm after a young boy went missing Friday in rough surf.

Coast Guard and local authorities spent hours searching for the 12-year-old boy who disappeared while body-boarding off the Outer Banks town of Corolla. The boy's mother reported seeing him go underwater and the board washing ashore without him.

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Coast Guard spokesman Lt. j.g. Scott Hembrook said the waves in the area weren't that high, only about 4 to 6 feet tall.

"What the storm is doing is creating a particularly strong undertow" that can pull swimmers to the bottom, he said. Undertow is created as water that's crashed onshore rushes back out to sea.

But for surf instructor Dave Houck, the building waves promised to be a weekend treat as Danny roiled well out to sea and was expected to churn north without hitting the mainland. He said he usually cancels classes when a tropical storm approaches, but he was on the strand Friday to coach some longtime students.

"This is what surfers love as far as the East Coast is concerned," said Houck, 33, of nearby Wilmington. "We don't want the mess. We just want the swells when the storm stays off shore."

On Friday afternoon, the storm was centered about 330 miles (535 kilometers) south of Cape Hatteras and moving north near 6 mph (9 kph). An increase in speed was expected, with a turn toward the north-northeast.

A tropical storm watch for the North Carolina coast was in effect Friday morning as Danny's maximum sustained winds of near 40 mph threatened to generate dangerous surf and rip currents along the East Coast. Small craft advisories were posted along the South Carolina coast.

On the Outer Banks island of Ocracoke, Anchorage Marina dock master Robert Raborn said the warnings of rough seas prompted the usual stream of weekend boaters crossing the Pamlico Sound to cancel reservations for overnight docking space.

"Pretty much everybody's canceled," said Raborn, 40.

The National Weather Service warned there could be swells as high as 7 feet offshore as the storm passed the area.

As he wheeled out bikes and surfboards at Pleasure Island Rentals on Carolina Beach, Craig McGinnity said if anything the offshore storm could boost weekend traffic from people who enjoy the rough surf. Most North Carolina schools opened for the academic year on Tuesday, so fewer families were planning beach vacations.

"We should see an uptick in business as the storm goes by," McGinnity said. "If they close the beaches, I won't rent out surfboards because I don't want to put people in danger."

Sylvia Jones said her 30-mile drive to work in Wilmington on Friday morning was clear, followed by passing rain and the sun warming through scattering clouds.

"I feel a little bit of the wind rustling, but the sun is coming out," she said. "It's just a typical weekend."

Meanwhile, officials on eastern Long Island were making emergency preparations for Tropical Storm Danny — even though it's expected to weakened considerably before reaching the waters off the New England coast this weekend.

Suffolk County spokesman Mark Smith says although Danny is barely a tropical storm, the area remains vulnerable to wave and wind erosion and coastal flooding.

New York City says it might restrict swimmers to shallow waters this weekend, and could even close beaches.

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