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Bonnie shuts down I-95 as it soaks Carolinas

CHARLESTON, S.C. - Tropical Storm Bonnie was downgraded to a tropical depression Sunday morning as its heavy rains soaked the coasts of South Carolina, southeastern North Carolina and eastern Georgia, ruining the start of Memorial Day weekend even as it weakened while moving northward.

The South Carolina Highway Patrol closed the southbound lanes on Interstate 95 in Jasper County about 20 miles north of the Georgia state line Sunday morning. I-95 is one of America's busiest highways, connecting Miami to the border of Canada in Maine.

Troopers say water is covering the road and they don't know when the highway will reopen.

The National Weather Service says up to 8 inches of rain fell in the area overnight.

CBS affiliate WCSC reports that at 8 a.m. Sunday, 15 hours after the second tropical depression of the season was upgraded to Tropical Storm Bonnie, maximum sustained winds had dropped to 35 mph, four miles per hour below the 39 mph threshold that defines a tropical storm.

The season's second-named tropical storm formed four days before the official start of hurricane season in the Atlantic Ocean, according to the National Hurricane Center.

The storm made landfall as a tropical depression along the Isle of Palms at around 8:30 a.m. Bonnie was moving north at 8 mph and tropical storm warnings remained in effect for the entire South Carolina coast.

Heavy rain and dangerous surf kept people off the Georgia, South Carolina and southern North Carolina beaches on Saturday. No evacuations have been ordered, with forecasters saying the biggest danger will likely be from locally heavy rain.

Officials in Charleston were monitoring the winds. The area has 15 bridges over water than are at least 65-feet tall that are closed when winds get 40 mph or above.

A Tropical Storm Warning is in effect for the South Carolina coast and forecasters said an isolated tornado or two will be possible early Sunday over the immediate coastal region from central South Carolina through southern North Carolina. The storm is expected to bring 2 to 4 inches of rain across much of the area this weekend, with 6 inches possible in some spots.

Near Myrtle Beach, authorities said they were worried mostly about heavy rain causing dangerous driving conditions as thousands of bikers and their motorcycles make their annual trip to the area.

The first Atlantic storm of 2016 was Hurricane Alex, which made an unseasonable debut in January over the far eastern Atlantic. The storm was the first hurricane to form in the Atlantic in January since 1938 and made landfall in the Azores on Jan. 15.

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