Dorot,

One of the first things I noticed when I was in Fla. was that doors
opened outward so they can not be blown in by high winds. I was told this
was a code requirement. You could certainly bar a door with a 2X4 as you
propose. I don't understand why you want a hinge for this. Double doors
often come with bolt type latches where the bolt slides into the floor.
These would look nicer than your bar. one on each door should hold them
closed

Dave M.