1 FEMA has already swung into action.
The Federal Emergency Management Agency, reshaped after criticism for its response to Hurricane Katrina on the Gulf Coast in 2005, was praised by local authorities for tornado response this year in Alabama and Joplin, Mo.
In preparation for Irene, FEMA administrator Craig Fugate has stressed local preparedness and evacuation orders by state and local officials. The agency already has sent to North Carolina such supplies as food, bottled water, medical equipment, tarps and generators, said Fugate, formerly Florida's director of emergency management. FEMA has dispatched teams "all the way up the East Coast, including Maine," and is coordinating with local officials, he said. The agency is stocking emergency supplies at Fort Bragg, N.C., Westover Air Reserve Base in Massachusetts and McGuire Air Force Base in New Jersey.
FEMA maintains commodities, including water, millions of meals and hundreds of thousands of blankets, at distribution centers. In Atlanta, the agency counts more than 520,000 gallons of water, more than 1.3 million meals and more than 16,000 cots and 56,000 blankets.
2Rain and flooding are the main danger. Forget the wind and fury. Hurricane Irene's most worrisome weapon is water.
There's just way too much of it: storm surge pushing seawater ashore and heavy rainfall causing flooding. That's not unusual with hurricanes, but with Irene there are a couple of added factors that are making meteorologist nervous.
This massive wet slow-moving hurricane is forecast to soak an already drenched Northeast and may come ashore at a time when tides are unusually high, making storm surge even worse — 4 to 11 feet with waves on top, forecasters say. MIT meteorology professor Kerry Emanuel said the flooding from Irene could be worse than the 1938 New England hurricane that killed 564 people.
"I think everybody is confident, unfortunately, that this is going to be a bad event from freshwater flooding," he said.
Forecasters predict Irene will dump 6 to 10 inches of rain in a swath from North Carolina to New England with some areas getting as much as 15 inches of rain. That's partly because the storm is unusually large and is moving fairly slowly — around 15 mph — allowing it to dump more rain over large areas.
"And all of this rain will come in a short period of time, and that could lead to life-threatening flash floods," National Hurricane Center meteorologist John Cangialosi said Friday.
3Experts are forecasting a multibillion-dollar disaster.
The economic impact of the hurricane largely will depend on factors that include the storm's size, where it makes landfall and the speed at which it's moving when it hits the coast. But experts already are forecasting billions of dollars in losses.
"It's probably going to be very damaging," said Roger Pielke, a University of Colorado professor and fellow of the Cooperative Institute for Research in Environmental Sciences.
A computer model of Irene's potential impact puts the estimated damage at $4.7 billion, according to research by Pielke and catastrophe-insurance provider ICAT. That figure, which came from analyzing 27 comparable storms dating back to 1913, includes destruction of homes, cars, public infrastructure and other property caused by high winds and flooding. The number doesn't factor in the added impact of lost sales from shuttered restaurants, quiet casinos, canceled flights and boarded-up stores —— all of which could add billions of dollars to the fallout.
The impact is expected to be significant for the nation as a whole because the major metro areas that will be affected, including New York City, Philadelphia, Boston, Baltimore and Washington, account for 16 percent of national economic output and 14 percent of total employment, according to Moody's economist Ryan Sweet.
Information from the Associated Press and Bloomberg News was used in this report.