Authorities on the east coast of the United States are bracing for the impact of Hurricane Irene.

Expected to make landfall over the weekend, the first hurricane of the Atlantic season is considered a class 3 storm – bringing winds of up to 115 miles per hour – and is expected to gather strength in the coming hours.

Officials from North Carolina to New York City are on high alert.

The US Navy has ordered its Second Fleet to leave Norfolk Naval Station in Virginia in order to protect vessels from the approaching storm.

Irene, currently over the Bahamas, has already caused havoc in the Caribbean.

In New York City, mayor Michael Bloomberg earlier warned residents of the low-lying and beach-front districts to find a place to stay on higher ground for the weekend.

Further south in the state of North Carolina, where Irene is expected by Saturday, people have begun evacuating the exposed strips of island on the coast.

Caribbean Travel

Irene has already caused havoc among holidaymakers in the Caribbean.

In Puerto Rico, Serenade of the Seas, operated by Royal Caribbean, was due to leave port at 20:30 on Sunday, but was instructed to depart at 17:30.

The line said that 145 people were unable to board the vessel – with many forced to make their own arrangements to rejoin the vessel in Aruba.

At the same time, about 300 vacationers missed the departure of the 2,758-passenger Carnival Victory, which was supposed to leave San Juan at 22:00 but was instructed to depart at 18:00.

Resorts in Turks & Caicos have also been forced to close following the impact of the storm.

In an illustration of the power of the storm, some 90 per cent of the homes on one remote Bahaman island - Acklins Island – were destroyed during a single night.