but also possible problem spots - bridges and roads that may be flooded out, areas that are prone to avalance, high traffic flow locations that may expeience gridlock, etc
Knowing where all the churches, schools and other "emergency Shelter" areas is also very helpful. After the hurricane Rita evacuation of Houston I made maps showing where every local emergency shelter was. The next time something like that happens I'll be passing these maps out to stranded people. That way they won't end up camped out on the streets of my neighborhood.
-Blast