A truck drives through a flooded street near the beach Hurricane Isaac approaches… (Dan Anderson / EPA )
WASHINGTON -- Federal officials warned Tuesday that slow-moving Hurricane Isaac could pummel southern Louisiana and neighboring states for more than two days, causing significant storm surge along parts of the Gulf Coast, dumping enough rain to cause widespread flooding, and spawning destructive tornadoes.
"As the center of the storm comes ashore tonight, that will not be the end of the event, it will be just the beginning," Rick Knabb, director of the National Hurricane Center, told reporters on a conference call.
Hurricane Isaac presents a "significant heavy rainfall hazard" because it is moving at only 10 mph, meaning it will linger longer than most hurricanes, Knabb said. Up to 20 inches could douse some areas, and heavy rain will likely fall hundreds of miles inland, he said.
PHOTOS: Bracing for Isaac
The hurricane could send Gulf of Mexico waters surging as high as 6 to 12 feet above normal along the coasts of Louisiana, Mississippi and Alabama, officials said. They have issued tornado warnings to communities east of the expected landfall.
For many, the time to get out of the storm's path has "come and gone," Knabb said. He urged residents to listen carefully to evacuation and other emergency orders.
President Obama has approved disaster assistance and has met with federal emergency management officials for regular updates on their preparations for Isaac. The storm is expected to roar ashore on the seventh anniversary of the day Hurricane Katrina devastated the region.
Louisiana Gov. Bobby Jindal, a Republican, expressed frustration that the White House has not agreed in advance to refund states for the costs of preparing for the storm.
But Craig Fugate, who heads the Federal Emergency Management Agency, told reporters Tuesday that the reimbursement request will be handled after Isaac passes. Such requests are "usually" considered once the emergency has ended, he said.
Isaac, which had been a tropical storm, was upgraded to hurricane status Tuesday morning when its winds picked up speed and were measured in excess of 70 mph.
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