US east coast braces for Florence

Tropical storm Florence could cause dangerous surf and rip currents along parts of the US east coast this weekend as it swirls across the Atlantic, according to forecasters at the National Hurricane Center.

Though weakened to a tropical storm, Florence is expected to regain hurricane strength as it nears Bermuda. Large swells are likely to start hitting the British island territory in the north Atlantic Ocean on Friday.

Forecasters say it is too soon to tell where the storm would go. Some forecast models show Florence slamming into land by late next week, while others indicate the storm would curve away from shore.

South Carolina's Emergency Management Division said although it was too early to tell if the storm would have any impact on the state, it was advising coastal residents to start making contingency plans.

"The risk of other direct impacts associated with Florence along the US East Coast next week has increased. However, there is still very large uncertainty in model forecasts of Florence's track beyond day (five), making it too soon to determine the exact location, magnitude, and timing of these impacts," hurricane specialist Robbie Berg wrote in a forecast advisory.

Improving atmospheric conditions were expected to allow Florence to regain its former strength. The storm reached major hurricane status Wednesday, peaking with maximum sustained winds of 210km/h.

Meanwhile, two low-pressure systems off the coast of Africa behind Florence also had high chances of developing into tropical storms, forecasters said.

"Since we are near the peak of hurricane season, this is a good time for everyone who lives in a hurricane-prone area to ensure they have their hurricane plan in place," hurricane specialist David Zelinsky wrote in a forecast advisory.

The National Hurricane Center said Florence's maximum sustained winds Friday evening were estimated to be 105 km/h. The storm was centred about 1457km east-southeast of Bermuda and moving west at 13km/h.