Hurricane Irene to Cause One of Largest Power Outages?

As U.S. East Coast residents snap up generators, batteries, and flashlights, experts are saying that Hurricane Irene could plunge much of the coast into one of the largest power outages ever caused by a storm, experts say.

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Electric power could go out from North Carolina's Outer Banks barrier islands—where Hurricane Irene will likely make its first U.S. landfall Saturday—to Maine, where Irene is forecast to hit by early Monday morning, according to meteorologist Jeff Masters.

"A foot of rain from eastern North Carolina to New York City will cause major problems," said Masters, director of the Weather Underground website.

Overall, Hurricane Irene is expected to drop 6 to 10 inches (15 to 25 centimeters) of rain along the East Coast, and could dump as much as 15 inches (38 centimeters) in some places.

The deluge could be especially troublesome in the mid-Atlantic states from Maryland northward, which have already seen heavy summer precipitation. The already saturated ground in the region, combined with Irene's high winds, could cause huge numbers of trees to fall on power lines, he said.

Irene's sheer size could also contribute to widespread power outages.

Hurricane specialist Eric Blake at the National Hurricane Center in Miami said Irene's circulation area is now about 600 miles (970 kilometers) across. This means that high winds from the storm will be spread over a very large area, increasing the likelihood of toppled trees.

Up and down the eastern seaboard, local officials are taking the blackout threat seriously.

On Friday morning Ken Creque, town manager of coastal Plymouth, North Carolina, said the western edge of Irene's eye is expected to pass about 50 miles (80 kilometers) east of his town Saturday night.

"Blowing debris and falling trees are my biggest concerns," Creque said. "If we have power when we wake up Sunday morning, we'll be extremely happy."

(Also see "Hurricane Irene 'Looking Bad' for U.S.—Moon May Make It Worse.")

Tropical Storm Irene Expected to Remain a Hurricane

As of Friday morning Hurricane Irene's center was north of the Bahamas and moving northward at 13 miles (21 kilometers) an hour.

The storm had weakened slightly, with peak winds of 110 miles (177 kilometers) an hour, making Irene a Category 2 hurricane—down from Category 3, the lowest category of major hurricane, on Thursday.

But the storm is expected to regain some intensity as it moves northward. Irene could again become a major hurricane—a storm with winds of 111 miles (179 kilometers) an hour or more—by the time it hits near Cape Lookout on North Carolina's southeastern coast in the wee hours of Saturday, as expected.

As Hurricane Irene moves north of North Carolina, the storm is expected to weaken.

Crossing the Chesapeake Bay early Sunday morning, though, Irene should still be a hurricane—though at Category 2 status, with winds below 110 miles (177 kilometers) an hour.

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"Substantial" Threat for Long Island

Later Sunday Irene is expected to make landfall on New York State's Long Island as a Category 1 hurricane, meaning it should have winds no faster than 95 miles (153 kilometers) an hour.

Meteorologist Keith Blackwell at the University of South Alabama's Coastal Weather Research Center said Long Island, unaccustomed to hurricanes, could be especially hard hit by storm surge—seawater pushed ashore by strong, swirling winds.

"Long Island is probably looking at a 5- or 6-foot [152- or 183-centimeter] storm surge," Blackwell said. "For up there, that's pretty substantial."

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