not possible. dade, broward and palm beach counties have about six million people (wiki). the other east coast counties have maybe another six mil. moving that many people before saturday is not going to be possible. counting four peeps to a car, that’s three million cars. more realistically it would be two peeps to the car and six mil cars.
if traffic moved briskly and orderly on all the roads out of the area, it is conceivable that the roads could move six thousand cars per hour. (a hundred a minute)
at that rate it would only take a thousand hours to move six million cars.
irma will be in the straits of florida, bearing down on miami in about sixty hours.
traffic won’t move briskly. it will congeal (is presently congealing) into bumper to bumper jams for the length of the highways.
it’s several hundred miles to safety. there isn’t enough gasoline in place to move that many cars that far. resupply? call houston. oops!
this is ominous! those who don’t make it out of there may (if noaa’s projection turns out to be accurate) have to deal with a category 5 hurricane. (it may downgrade to a 4 or even a three.) people caught in a traffic jam on a limited access highway will face life threatening conditions.
shelter in place? sustained wind speed as of the most recent noaa advisory – 185 mph with gusts over 200. it better be a really good shelter!