We are finding out.

they are trying to get 650,000 people out of Miami. But that is not the whole population. Floridians are much better at this than most other people.

Yeah, except for that gas stations running out of fuel issue. That's what happens when everybody decides to fill their tanks at the same time. Good that they are giving fuel tanker trucks a police excort in.

As has been said so often on this site, evacuate early and be ahead of the crowd.

I believe that given enough money and effort, that most modern cities CAN be evacuated.
It would take some days and be hugely expensive, but in most cases I believe it can be done.
This of course presumes that some relatively slow moving disaster such as a hurricane is approaching.
In the case of a disaster that gives little warning, such as a tsunami, I doubt that evacuation could be completed in time.

In the case of a nuclear detonation without warning, it is more of a case of rescuing the survivors rather than evacuation.

Martial law might be needed to keep traffic moving, requisition vehicles and fuel supplies and so on.
And of course most of those evacuees will need shelter and supplies, a non trivial undertaking.
Shopping list for sheltering evacuees.
2 million folding or inflatable beds
6 million blankets.
10 million bottles of water.
10 million MREs.
250,000 tents each to sleep 10 persons
250,000 portable lighting units
25,000 generators each 20KVA.
250,000 chemical toilets.
2 million rolls toilet paper.
And many other supplies, fuel, medicines, showers, soap, towels, clothing, soaps and detergents, tableware, communications equipment, Heating equipment and fuel, and so on.

And enough secure storage space to keep it all, outside the disaster zone, but not too far away.
Enough vehicles to transport it all, a few thousand trucks should do.

Remember also that trying to move a few million people will lead to significant loss of life from auto accidents and other mishaps.

Planning to shelter in place might be more sensible.

Just trying to get out of Nebraska after the eclipse was an eye-opener for me. And I had enough gas to get all the way home without refueling....

Evacuation has the problem of being unable to spread out the movement over time. And people aren't real good at following orders - especially those who are told to go first. Just look at the airplane boarding process at the airport as a small scale example.

The aware prepper will get out WAY early. God bless the public safety folks who stay behind to shoo everyone else out.

Revised; I think some cities could, given good weather, open highways and 5 -6 days to move everyone

yes ... the interesting thing is actually the "psychology" of the people. I was looking at that - on the commentaries here after Irma. It appears that a lot of Florida locals really left the "evacuation decision" until the final 24-hours before the storm hit. It seems as though people have to feel that "disaster is absolutely bearing down on them" before they will make a big move. A lot of Floridians did top off their gas tanks and buy supplies from the supermarket ... but as far as "getting out early" ... not so many did this. There is something primeval in the human mindset that tells us to "hunker down".

In fairness to the residents of Miami - they did evacuate when they were told to leave. That was a LOT of people on the highways.

More than anything else - this _psychological reluctance_ to evacuate early ... this torpedoes any hope of evacuating large cities.

But on the positive side ... those few who do get out early have got more open space in front of them.

Not really primeval. Normalcy bias and a desire to protect their property. They have not been hit hard since Hurricane Andrew, and many of the residents in Florida did not live there then. They have seen hurricanes, and not suffered much damage or seen a real threat to life.

The reports of looters in Houston did not help motivate them to leave either.

Every storm is a new situation.

In the case of Irma, it's enormous expanse (hurricane-force winds wider that the Florida peninsula, tropical force to near 400 miles) and the fact it was going to run north up the peninsula both made people like my brother in Naples think: 1) may need to evacuate; 2) could get stuck on a highway - no gas -- and be forced to ride out the storm in the car.

Irma ended up impacting Alabama, Georgia (Atlanta's first-ever tropical storm warning) and South Carolina.

Evacuate several days before a weather forecast predicts landfall? Maybe, if you won't be fired for leaving work so long. Maybe, if you can afford it. That many days in a hotel is prohibitively expensive for many people.

Some folks couldn't even afford the gas.


Can any modern city be evacuated?

Sure, eventually. Quickly enough to do any good? Depends on the scenario.

Nearly 40% of the residents of my city -- Washington, D.C. -- don't own a car. The subway system will transport many to outside the Beltway but what then? Capital Bikeshare bicycles currently number 3,700 so those would quickly disappear.

We had a bit of a run-through here on September 11, 2001. Hundreds of thousands of workers evacuated to the suburbs that day by car, subway and walking. I thought about leaving but I live here and there is a strong tendency to hunker down at home.

I've posted many times in ETS on this subject. The prospect of having to quickly evacuate is grim. On a normal day, our roads are gridlocked for several hours. And that's just the commuters.

How far would we have to go?

I long ago came to the conclusion that if I had to evacuate "quickly" I'd have to do so by bicycle, or motorcycle if I had one.

It's a bleak scenario.


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When making an individual or family emergency plan, I don't think that it's reasonable to trust in the availability of shared transportation assets like public transit, rental cars and car sharing services, ride sharing services, taxis, public bicycles, and so on.

But I also agree that having a bicycle for every member of the family might be the quickest way to escape when traffic is bad. Keep in mind the distance that you need to traverse -- only the very hardiest residents of Miami could have gotten out of Irma's path on a bicycle.