Tropical Storm Erin is moving west at 17mph (28km/h) and could become a hurricane by Friday, the US National Hurricane Center (NHC) says.

At 11:00 AST on Wednesday, Erin’s centre was about 1,305 miles (2,100km) east of the northern Leeward Islands, with maximum sustained winds of 45mph (75km/h).

Climatologist Dale Destin says a tropical storm watch for Antigua and Barbuda could be issued by Thursday.

Forecasters expect the storm to shift west-northwest over the weekend, passing near or just north of the northern Leewards. Swells may affect the Leeward Islands, Virgin Islands and Puerto Rico, creating dangerous surf and rip currents.