Hurricane Katrina's front-right quadrant contained the storm's strongest winds. They pushed water from the Gulf of Mexico into a storm surge of more than 20 feet (6 meters) at the point where Katrina made landfall in Mississippi. Extensive damage has been reported in Biloxi and Gulfport.
The hurricane also bulldozed a storm surge of about 10 feet (3 meters) into Alabama's Mobile Bay.
Steve Huffman, a spokesman for the Mobile County Emergency Management Agency in Alabama, said at least eight feet (2 meters) of water surged through parts of downtown Mobile, where Huffman rode out the hurricane at the agency's headquarters.
"It was howling pretty good," he said. "I stepped outside a few times to see what was happening.
The wind was blowing pretty good, and the trees were trying to turn themselves into pretzels out there. In the distance you could hear transformers popping and hear tree limbs breaking."
Despite the strength of the storm, no deaths or serious injuries have been reported to Mobile authorities, Huffman said.
Randy McKee, the meteorologist in charge of the National Weather Service's Mobile office, said Katrina's winds didn't diminish to less than 30 miles an hour (48 kilometers an hour) until around midnight Monday.
"It was a long-duration event," McKee said. "It was so big and had such a large wind field, it took a long time even after the eye passed the northwest Alabama coast. It was with us all day and into the night."
McKee said many streets in Mobile are blocked today by downed trees and power lines.
Hurricane Katrina is the latest storm to strike the hurricane-prone Gulf Coast since Hurricane Ivan made landfall in September 2004. Hurricane Dennis made landfall on the western Florida Panhandle last month.
Willie Drye is the author of Storm of the Century: The Labor Day Hurricane of 1935, published by National Geographic.
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