MIAMI?US authorities ordered the evacuation Wednesday of thousands of tourists and residents in North Carolina as Hurricane Earl, the strongest Atlantic storm of 2010, wreaked havoc on Labor Day holiday plans.

Briefed by top disaster response aides, US President Barack Obama said officials were preparing for the "worst case" scenario and would do all they could to protect vulnerable east coast communities.

On the final weekend of the US summer holiday, thousands who had planned end-of-season trips were forced to abandon the North Carolina beaches as the coastal region braced for the arrival of the category three storm.

Experts said Earl -- once a potentially "catastrophic" category four storm -- would spin northeast of the Bahamas on Wednesday, taking aim at coastal North Carolina, with landfall possible early Friday.

At 11:00 am (1500 GMT) the storm was centered about 725 miles (1,170 kilometers) south-southeast of the beach retreat of Cape Hatteras, North Carolina, and packed winds of 125 miles (205 kilometers) per hour.

Projections from the Miami-based National Hurricane Center showed there was a chance Earl could make landfall as far north as New England before it peters out.

News reports said authorities as far north as Long Island, just outside New York City, were also weighing an evacuation order.

Craig Fugate, head of the Federal Emergency Management Agency (FEMA), told ABC television that numerous towns and cities in the storm's path would face similar tough evacuation decisions in the coming days.

"It's really based upon each community," Fugate said, adding that the key was to issue the orders early enough so residents actually had time to flee before the violent weather arrived.

"Unfortunately, it sometimes means the evacuation may start with blue skies and clear weather, and people don't get that sense of urgency."

Earl, which brushed past Puerto Rico on Tuesday, has already pummeled the Bahamas and eastern Caribbean with rain and heavy winds that downed trees, damaged homes, blocked roads and snapped power lines.

Throughout the day on Wednesday, the Bahamas were due for large swells that "could cause dangerous surf conditions and rip currents," the NHC warned.

About 174,000 people lost power in Puerto Rico and 33,000 were left without water, while thousands more lost power on the French islands of Saint Martin and Saint Barthelemy.

Earl comes on the heels of Hurricane Danielle, blamed for rough surf and riptides in New York and New Jersey last weekend.

Meanwhile, tracking closely behind Earl is Tropical Storm Fiona, which was expected to pass over or close to the northern Leeward Islands later Wednesday, packing top winds of 45 miles (75 km) per hour.