To quote Hank's saying. "What Clark said".

I can't think of the NHC Director calling me and telling me to evacuate my City. Steve, that call kind of filters down to you. Please get out. And that goes for anyone in the Warning area. Do what you have to tonight. So you can leave at first light.

I-10, I-59 and I-55 will be crowded to say the least. I think this was expected, as I saw Barricades in place along the Interstate on my way to work tonight. I'm 90 miles North of Gulfport and 150 North of New Orleans.
Do the math with 250,000 vehicles and see how far they stretch. At 25 ft per vehicle. That's 1184 miles of road. I'll let you finish the rest.

Like I said earlier, and a few times last year. If you are near an area under a HURRICANE WARNING. Do not wait for the order to become mandatory!