I don't know what happened during/after Katrina, but I was told by several people that in (I think) 1964, a massive snowstorm hit the Eugene/Springfield, OR area (probably a much wider area, but this was my info source). This is a mild-winter area, and if they have snowplows, I've never seen them.
I was told that when the snow finally settled at an average depth of four feet (not counting drifts), the whole area was paralyzed. Many women who were anywhere near to giving birth must have worried themselves in to going into labor.
The whole area became dependent on those people who had 4WD vehicles and, to a lesser extend, CBs. I don't know if there was some central info receiving/disseminating or not, but I heard that when a woman went into labor and needed to get to the hospital, they sent out the nearest person (we'll say 'guy') with a 4WD who had volunteered his services, he would pick her up and transport her to the hosptial.
I am assuming that this same system was used for injuries, etc.
Ah, Mother Nature's idea of a big joke!
Sue