Louisiana governor Kathleen Blanco this morning urged people who evacuated to remain outside the region until officials have determined it is safe to return.
While reports are sketchy at best at this time, parts of New Orleans have been confirmed to be underwater, the Superdome has developed a hole in its roof and is leaking water inside, and power and telephone service have been lost in much of the city.
To the east, downtown Mobile, Ala., is completely underwater.
Officials have evacuated 911 call centers across the region and most areas are without 911 emergency service, even if telephones are working.
Reports are widespread across the region of people who did not evacuate being forced to their attic or even to their roof as a result of floodwaters. There are unconfirmed reports of historic buildings collapsing. Officials have not yet been able to go outside to survey the damage.
Even so, damage in New Orleans is likely to be less than the worst case scenarios previously predicted, as the eye of Hurricane Katrina passed to the east of the city and the hurricane gained northward speed.
Reporters from the New Orleans Times-Picayune are posting updates and damage reports throughout the day for the city and the entire area on their Web site.