Still shaken by Tuesday's earthquake, the East Coast braced Wednesday for Hurricane Irene, which threatened to wreck the plans of weekend beachgoers and disrupt the Martin Luther King Jr. Memorial dedication Sunday on the National Mall in Washington, D.C.

The powerful hurricane was expected to dump several inches of rain Saturday as it churns along the Atlantic Coast.

And although it was still hundreds of miles away, meteorologists said it could produce stormy and treacherous conditions along the beaches of North Carolina, Maryland, Delaware and New Jersey as it passes.

Forecasters said they expected the worst Saturday night, as the storm center passes off the Virginia capes. By noon Sunday, Irene is expected to be off Atlantic City, N.J., and accelerating north into cooler water.

But the storm could leave lingering rain bands and blustery wind in its wake, as tens of thousands of people, including President Obama, assemble for the 11 a.m. EDT memorial dedication on the Tidal Basin.

Organizers said the ceremony will be held rain or shine, but the project's executive architect, Ed Jackson, said it could be pushed back if necessary.

The hurricane, a Category 3 storm on the Saffir-Simpson scale, was in the Bahamas and heading northwest Wednesday, with sustained winds of well over 100 mph.

The National Hurricane Center expected the storm to intensify and reach Category 4 strength, with winds of more than 130 mph, by Thursday.

It was forecast to turn north, then northeast, brushing past North Carolina's Outer Banks and accelerating toward New Jersey and New England, then gradually weakening.

Evacuations were under way along the North Carolina coast Wednesday.

"They're going to be experiencing hurricane-force gusts to 80 mph in, like, Morehead City," said Paul Walker, a senior meteorologist with AccuWeather, a private weather-forecasting agency. "Hatteras could have a major hurricane if this thing stays on its current track, with wind gusts of 125 mph."

Andy Woodcock, a meteorologist with the National Weather Service in Sterling, Va., said, "This is a pretty big storm right now."

On Wednesday, Irene roared across the entire Bahamas archipelago, knocking down trees and tearing up roofs and posing the most severe threat to the smallest and least populated islands, officials said.

Bahamian Prime Minister Hubert Ingraham said there had been no deaths or major injuries according to preliminary reports he has been receiving from throughout the widely scattered islands. But he added that they would not know the full extent of damage from the Category 3 storm until it is clear of the country on Friday.

Irene barreled through the Turks and Caicos Islands late Tuesday as a Category 1 hurricane, blowing off some roofs and downing power lines, said Emily Malcolm, district commissioner for South Caicos Island.

No deaths or injuries have been reported, she said.

Puerto Rico, which also was hit by Irene, is still struggling with heavy flooding that has stranded motorists and affected several neighborhoods. Dozens of landslides have been reported and 765 people remain in shelters, Gov. Luis Fortuno told a news conference Wednesday, two days after he declared a state of emergency.

On Tuesday, a 62-year-old woman died at a hospital after trying to cross a swollen river in her car near the capital of San Juan, police said.

In the Dominican Republic, flooding has stranded at least 85 communities, and nearly 32,000 people have been evacuated.