Winds gusting strong enough to roil whitecaps are expected along the South Carolina coast by Sunday as a storm now off Florida passes a little closer to shore than previously thought.

The National Hurricane Center on Friday drew the area where the storm could become at least a tropical depression — a weak tropical storm, to include the coast from Charleston north into North Carolina.

Forecasters raised the chance of it becoming tropical to 50 percent.

The storm still is expected to remain offshore while passing South Carolina. But the actual track remains uncertain and the forecast has become complicated, meteorologists with the National Weather Service in Charleston said.

"This system is expected to cause increasing northeast winds and rough surf along the coast of Georgia and the Carolinas through early next week," said hurricane center specialist Dan Brown.

"At this point it's not looking like a huge threat to any land area," said meteorologist Carl Barnes of the National Weather Service in Charleston.

Gusts could push to 30 mph, near gale force. The strengthening winds will heighten the risk of rip currents. Stronger surf could cause some beach erosion, Barnes said.

Offshore, wave heights approaching 6 feet by Sunday, combined with the winds, are going to create hazards for small craft, said Weather Service meteorologist Neil Dixon.

Showers and thunderstorms could haunt the coast. But forecasters don't expect widespread rain or flooding, Barnes said.

If the storm passes close or along the shore, it could bring stronger winds and rain and push them farther inland.

Brown continued to call for heavy rain and flooding across southern and central Florida over the weekend as the storm crosses the state before turning up the Southeast coast.

On the bright side, the action should bring drier air from the north and more pleasant temperatures to the Lowcountry, Barnes said.

Sunday's high will be in the mid-80s; Monday's in the low 80s.

Reach Bo Petersen Reporter at Facebook, @bopete on Twitter or 1-843-937-5744.

Science and environment reporter. Author of Washing Our Hands in the Clouds.