Florida is on high alert as Hurricane Irene gains strength in the Caribbean.

Yesterday, the first Hurricane of the Atlantic season smashed the Dominican Republic, delivering heavy rain and high winds as well as dangerous sea surges to the holiday island.

However,  Category 2 Irene will become even more ferocious, possibly increasing to a Category 4 before belting Florida and North and South Carolina at the weekend.

Meteorologist Chris Landsea from the U.S. National Hurricane Center (NHC) in Miami said it wasn't anticipated Urene would be so strong so early. 

He said that the ocean's warm temperatures and the current atmosphere was 'very conducive' to energising storms.

The National Hurricane Center has warned of storm surges, which will

raise water levels between nine to 13 feet above normal tide levels in

the Turks and Caicos and up to four feet in the Dominican Republic,

also resulting in large and dangerous waves.

Irene is the first hurricane to threaten the U.S. mainland in almost

three years. If it becomes a Category 4 storm, winds could reach up to

155 miles per hour.

Craig Fugate, an administrator at  the Federal Emergency Management

Agency has warned that it is 'critical' that people in Florida 'take

this storm seriously'.

At least 12 cruise ships in the Caribbean have changed their routes to avoid the storms including vessels owned by Carnival and Royal Caribbean.

Puerto Rico lost power to half of the island and more than 100,000 don't have a water supply after the hurricane struck on Monday.

And US President Barack Obama has declared the island state a 'disaster area' giving it access to emergency funds to aid the recovery.