COLUMBIA, S.C. — Tropical Depression Bonnie caused a holiday traffic nightmare on Interstate 95 Sunday after the storm system dumped heavy rain causing road closures and miles-long backups, officials said.

The South Carolina Department of Transportation said I-95 Southbound at the U.S. 17 exit, about 22 miles north of the Georgia border, was blocked because of water on the road. Traffic was also partially blocked in the northbound lanes.

The South Carolina Department of Public Safety set up a detour. Several other roads nearby also were closed.

Doppler radar estimates showed five to seven inches of rain had fallen in a narrow section of Jasper County near I-95. Cars stalled as water covered the busy north-south interstate.

Bonnie made landfall at the Isle of Palms near Charleston around 8:30 Sunday morning. The National Hurricane Center downgraded Bonnie and canceled the tropical storm warning for the South Carolina coast.

As of 5 p.m. ET, Bonnie was located 25 miles west-northwest of Charleston and 100 miles west-southwest of Myrtle Beach. Maximum sustained winds were 30 mph.

The system pumped its brakes, became stationary and the rain totals rose, WCNC-TV reported.

Storm surges and rip currents were forecast along portions of the Atlantic Coast. Later Sunday, the storm was forecast to move up along the Mid-Atlantic coast and into New England on Memorial Day. Rain began falling in the Washington, D.C., area late Sunday afternoon, after the annual "Rolling Thunder" motorcycle ride honoring fallen service members rumbled past the U.S. Capitol and national monuments.

Bonnie, the second tropical storm of the season and the first to threaten the U.S. coast, arrived just in time to disrupt Memorial Day weekend plans for beachgoers.

In Florida, Brevard County Ocean Rescue crews pulled 27 people out of the rough surf caused by Bonnie on Saturday.

“We’re actually doing a little better (Sunday) than what we saw yesterday,” said Eisen Witcher, chief of Brevard County Ocean Rescue. “We do expect the rip currents to linger a little bit into Memorial Day,” he said, adding that Brevard’s shoreline was packed with beachgoers.

The National Weather Service reported a moderate risk for strong rip currents Sunday. Some of the strongest rip currents — channels of fast moving waters that pull out from the beach back into the ocean — were reported along the south Brevard beaches.

Further north, near Jacksonville, St. Johns County Fire Rescue said it had rescued 13 swimmers in distress. It expected a rip current advisory to remain in effect through Sunday.

In Neptune Beach, a 13-year-old boy was bit on the leg by a shark estimated to be five to six feet long by lifeguards, according to the Neptune Beach Police Department.

Police said the teenager, who was not seriously hurt, was swimming in two-and-a-half feet of water when the shark bit him.

Lifeguards estimated size of the shark from the bite pattern on the boy's calf and shin.

It was the first shark bite at Neptune Beach this year, authorities said.

Contributing: J.D. Gallop, Florida Today, and WTLV- and WJXX-TV, Jacksonville