I think there were two (maybe more) evacuation orders. The really urgent "mandatory" one was on Sunday. An earlier order was not mandatory, but urged preparation for an evacuation.
The plan calls for a three day evacuation.... he called one on Sunday after Bush called him...one day before the storm hitting.
Mayor Orders Evacuation Of New Orleans As Katrina Approaches
"Mayor Ray Nagin ordered an immediate evacuation Sunday for all of New Orleans, a city sitting below sea level with 485,000 inhabitants, as Hurricane Katrina bore down with wind revved up to nearly 175 mph and a threat of a massive storm surge.
Acknowledging that large numbers of people, many of them stranded tourists, would be unable to leave before the eye of the storm strikes land sometime Monday morning, the city set up 10 places of last resort including the Superdome arena.
President Bush urged people living in the path of Katrina to take the storm extremely seriously and follow orders to evacuate to higher ground.
A day after declaring an emergency for Louisiana, Bush declared an emergency for the state of Mississippi.
"We cannot stress enough the danger this hurricane poses to Gulf Coast communities," Bush told reporters on his ranch in Crawford, Texas."
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