KEVIN MAURER

The Associated Press

CAROLINA BEACH, N.C. (AP) - Tropical Storm Danny was losing steam early Saturday as it passed offshore of the Carolinas, but was still expected to produce a second straight weekend of dangerous surf along the East Coast.

Large waves and treacherous rip currents were forecast from the Carolinas to New England, though forecasters said the storm was not expected to come ashore and preliminary reports indicated it was being absorbed by a frontal low early Saturday.

The dangers of storm-agitated waters were demonstrated after a young boy disappeared Friday in rough surf off North Carolina. The boy's mother reported seeing him go underwater off the town of Corolla, not far from the Virginia line, and the board washing ashore without him.

The Coast Guard and local authorities spent hours searching for the 12-year-old boy, who had been body boarding, but called off the search around 9 p.m.

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.

Farther north, the Massachusetts Department of Conservation and Recreation was closing beaches in five communities until further notice. The agency also canceled all public ferry service in and around Boston on Saturday, citing potential high seas, strong currents and heavy rain. State authorities urged boaters to have their vessels securely moored by Friday night.

Early Saturday, the storm was centered about 190 miles (300 kilometers) south of Cape Hatteras and moving north near 17 mph (28 kph). Forecasters said preliminary reports from a reconnaissance plane indicated that Danny was being absorbed by a frontal low over North Carolina.

A tropical storm watch was in effect for the North Carolina coast as Danny maintained top winds near 40 mph, though forecasters said the watch would likely be discontinued by later Saturday morning. A watch means tropical storm conditions are possible within the watch area. 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.

Some coastal residents were looking forward to Danny's effects. In this community 40 miles north of the South Carolina line, surf instructor Dave Houck said the building waves promised to be a weekend treat. 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."

Associated Press writer Emery P. Dalesio in Raleigh contributed to this story.