The fact that they aren't a usual event is probably exactly the challenge here.
I’ve lived in a place where it flooded every year or two. It floods regularly where I live now too.
Locals know which roads to avoid and not to drive into a flood.
Floods aren’t a usual even.
Have you ever even been outside?
It may not be usual in Atlanta itself, but living on the Southeastern coast within a mile or two of the water, for 30+ years, it’s a surprisingly common occurrence. I’ve got old photos around of kayaking through downtown Charleston during college, for instance, where the street flooding is not only usual but a many times per season occurrence. Lots of seaside areas have the same issue.