Irene weakened slightly Friday, dropping down to a Category 2 storm with maximum sustained winds near 105 mph. But some re-strengthening was possible and the storm was expected to be near the threshold between a Category 2 and 3 storm as it reached North Carolina's coast, the National Hurricane Center said.
New Jersey and Delaware are under states of emergency as Irene moves closer.
"One of my greatest nightmares was having a major hurricane go up the whole Northeast coast," Max Mayfield, the National Hurricane Center's retired director, told The Associated Press on Thursday as the storm lurched toward the U.S. "This is going to be a real challenge ... There's going to be millions of people affected."
The hurricane would be the strongest to strike the East Coast in seven years, and people were already getting out of the way. After dousing the Bahamas, it was again moving over warm Atlantic waters that will energize it.
Hurricane warnings have been posted for Philadelphia and Delaware Counties, all of Delaware and South Jersey. This means hurricane conditions are expected to develop within 36 hours. Mercer, Montgomery, Chester and Bucks Counties are under tropical storm warnings.
Action News meteorologist Karen Rogers says Irene is a very large storm and the impact will likely be felt far inland, not just along the coast.
The latest track takes it near Morehead City, North Carolina near Cape Hatteras on Saturday, then up over Sussex County, Delaware as a CAT 2 hurricane and over Cape May County, NJ on Sunday. As it moves inland, it will likely weaken to a CAT 1 hurricane as it moves up toward the Hudson Bay. This would bring flooding rains, 7-10" or more and damaging winds into our region.
No matter the track, dangerous rip currents will be present in the ocean waters along Delaware and New Jersey beginning Friday and probably not subsiding until Sunday night.
Tens of thousands of visitors to the New Jersey shore and many residents began a mostly orderly exodus Thursday after a series of requests to evacuate - including mandatory orders to exit Atlantic City and all of Cape May County which were expected to make the flight from Hurricane Irene the biggest evacuation in state history.
Atlantic City's 11 casinos were bracing for a likely shutdown that would be only their third since opening in 1978.
All told, Irene could cause billions of dollars in damages or more along the Eastern Seaboard in a worst case scenario, said Kathleen Tierney, director of the Natural Hazards Center at the University of Colorado.
The first U.S. injuries from Irene appeared to be in South Florida near West Palm Beach where eight people were washed off a jetty Thursday by a large wave churned up by the storm.
The beach community of Ocean City, Md., was taking no chances, ordering thousands of people to leave.
"This is not a time to get out the camera and sit on the beach and take pictures of the waves," said Maryland Gov. Martin O'Malley.
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