Of course not. But they have a right to some input, seeing as its their dime.
The Feds do have input. NOAA is a Federal organization.
There is no evidence that Federal policy makers are any more competent than local policy makers when it comes to declaring evacuations.
Yes, the feds are not quite as attached to New Orleans as the mayor and local population is. Therefore, the feds have the clarity of judgment and objectivity to recognize however unfortunate that New Orleans is facing imminent destruction.
The locals are blinded by home-pride and denial to recognize that the land that their ancestors harvested is going to be wiped out. Who wants to acknowledge that their home will be destroyed and the above-ground tombs of their relatives will be swept around and littered throughout the land? The person that has no attachment to them.
...seeing as how it's OUR dime.