Mayor Ray Nagin closed City Hall and schools early, and residents were advised to remain inside until the flood danger abated. The Army Corp. of Engineers closed a gate in a suburban canal to stop floods from topping a wall.
In Jefferson Parish, one of the areas most damaged by Katrina, another flood gate was closed to avoid putting pressure on flood walls, and motorists across the city were asked to remain off the roads to avoid directing floodwaters into homes and offices.
Emergency preparedness officials said all the city's pumps were working properly, according to an Associated Press report.
By Monday afternoon, rains eased to scattered showers, but the storm system caused more damage to surrounding areas as it moved north east.
"Homes and buildings in rural western Alabama were damaged by possible tornadoes and other parts of the state had road flooding and wind damage, according to Alabama emergency management officials and the weather service," the AP reported.
Despite problems caused by flooding, the rain relieves some dry areas of Louisiana.
Until Monday's downpours, rainfall for New Orleans was about 11 inches below normal for the year, the AP said.