Parts of the East Coast are in for a soggy weekend as a developing tropical storm swirls over the Atlantic, prompting tropical storm warnings from South Carolina to Maryland as the system makes its way toward land.

The area of low pressure -- called Potential Tropical Cyclone 16 -- is expected to strengthen into a tropical storm by the time it reaches North Carolina's coast Friday and begins a three-day push up the coast, the National Hurricane Center said.

TRACK THE STORM

Rain will stretch hundreds of miles from the storm's center, often joined by gusty winds. Impacted areas could also see hazardous storm surge and coastal flooding, strong rip currents and rough surf.

A few tornadoes are also possible in parts of the coastal mid-Atlantic.

The storm system was about 330 miles east-southeast of Charleston, South Carolina, at 5 a.m., with maximum sustained winds near 50 mph, the hurricane center said.

It will likely be named Ophelia but could also be dubbed Philippe, depending on when it's named.

A tropical storm warning stretches from Cape Fear, North Carolina, to around the Maryland-Delaware state line. Parts of that coastline are also under storm surge warnings and watches, with 1 to 5 feet of surge possible in coastal areas from around Pamlico South to Delaware Bay.

Coastal areas also will bear the brunt of the heaviest rains, though inland residents will get storms, too.

The Carolinas and Virginia are expected to begin seeing the downpours Friday, with the greatest risk of heavy rain and flooding expected in eastern North Carolina and southeast Virginia, where 3 to 5 inches are forecast. Some places could see as much as 7 inches of rain.

A broad stretch of the Mid-Atlantic into southern New England could see 2 to 4 inches of rainfall from late Friday through the weekend.