Hurricane Irene 2011: More Than 2 Million People Told To Move To Safer Places

As the storm's outermost bands of wind and rain began to lash the Outer Banks of North Carolina, authorities in points farther north begged people to get out of harm's way. The hurricane was still packing 100 mph winds late Friday, and officials in the Northeast, not used to tropical weather, feared it could wreak devastation.

"Don't wait. Don't delay," said President Barack Obama, who decided to cut short his summer vacation by a day and return to Washington. "I cannot stress this highly enough: If you are in the projected path of this hurricane, you have to take precautions now."

Senior hurricane specialist Richard Pasch of the National Hurricane Center said there were signs that the hurricane may have weakened slightly, but strong winds continued to extend 90 miles from its center.

The moment Saturday when the eye of the hurricane crosses land "is not as important as just being in that big swath," Pasch said. "And unfortunately, it's a big target."

Hurricane warnings were issued from North Carolina to New York, and watches were posted farther north, on the islands of Nantucket and Martha's Vineyard off Massachusetts. Evacuation orders covered at least 2.3 million people, including 1 million in New Jersey, 315,000 in Maryland, 300,000 in North Carolina, 200,000 in Virginia and 100,000 in Delaware.

"This is probably the largest number of people that have been threatened by a single hurricane in the United States," said Jay Baker, a geography professor at Florida State University.