When Helene hit Florida, it was at its most powerful and by the time it arrived points north, it had been downgraded, but it was still damaging rain-wise. Still Florida managed to have few casualties, and I can only point out that the reason might be simply preparation based on past experiences. Florida has become quite enlightened about getting ready for hurricanes and assorted disasters and the system is checked and improved after every season.
And I am not going to badmouth or bash the other states for their casualty count. I believe they have not seen something like this before nor could they imagine the consequences. My hope is that rather than start demanding global warming/climate change solutions, they actually start working on how to mitigate the next big storm that may come their way.
It won’t be easy or cheap, but it will pay off in the future. You guys will need more Prepper Mindset and Less Greta Bullshit.
Some, undoubtedly, is familiarity with what to do in event of hurricane. But I have to wonder, looking at the map, whether some of it is normalization, in the math sense. For instance, you could divide the deaths by the land area affected (perhaps using a further normalization of volume of water dropped), or average population per square mile in the storm track.
We had several days of rain before Helene hit, so the ground in the mountains was already saturated. Then, many places in the mountains got 15" of rain dumped on them. These mountains haven't seen anything like this 1000 year storm in recorded history. The topography of the mountains has been changed. There are NO roads that survived running from my town on the Tennessee state line into Western North Carolina. We are doing well, because of our preparations, but I know people who live completely off grid, but either were away and trapped at the base of their mountain, or are trapped on the mountain because most of the roads are simply gone. There are many people who aren't waiting to be "rescued". They're cutting their own routes in and out.
There's no prior experience here with a storm like this. After the rain stopped, the water continued to rush downhill, and the high winds started. That took out trees in swathes, further loosening the ground and contributing to the landslides. Entire mountain towns were literally wiped off the map with nothing but a debris field to show that they were there.
But the people here are strong and determined. Rebuilding has already begun, and even though it's going to take years to recover, we will.
ScottTN