←back to thread

156 points Brajeshwar | 1 comments | | HN request time: 0s | source
Show context
aqme28 ◴[] No.41830080[source]
While useful, it's my impression that the storm surge is the most dangerous part of a hurricane, and oysters unfortunately don't do much about that.
replies(3): >>41830536 #>>41830538 #>>41831185 #
patmorgan23 ◴[] No.41831185[source]
Hurricanes present a triple threat. In no particular order they are 1) Storm surge, 2) insanely high winds, 3) torrential down pour and the resulting flash flooding.

Immediately along the coast the storm surge is probably the most destructive as it's a wall of water that hits and then pulls everything out to sea, but once you get a few hundred feet inland, or some elevation, it's not really a problem.

Hurricane wind speeds are comparable to tornado wind speeds, except the storms are so much bigger. They will throw projectile debris at windows, and then they break the resulting change in pressure will blow out and rip the roof of a home clean off.

Then the incredible amount of rain they generate can create devastating flooding, and this can happen hundreds of miles from the coast(this is what happens in Asheville, North Carolina, and the specific geography made the flooding worse and harder to recover from since Asheville is a mountain valley river town)

replies(1): >>41831493 #
1. WarOnPrivacy ◴[] No.41831493[source]
> but once you get a few hundred feet inland, or some elevation, [surge is] not really a problem.

[more clarification than correction] Along the US gulf coast, surge will travel miles inland thru waterways and drainage basins. When it's over, many places drain right away while some can take weeks.

Depending on the storm, an area can get multiple surges.

> Hurricane wind speeds are comparable to tornado wind speeds, except the storms are so much bigger.

[same] Inland wind risk is closely tied to wind field size and relative position to the eye's direction of travel. We're 30 min inland from the gulf. Every factor about Milton (@36h out) was a factor in our risk calc. With Helene, we didn't have to calc anything. But that weekend, we drove the 30 min to help clean/gut houses on the coast.

And to support your synopsis, I describe cat 4/5 landfalls as x hour tornadoes.

> Then the incredible amount of rain they generate can create devastating flooding, and this can happen hundreds of miles from the coast

In the mid 90s we did relief in Athens Ga (from Alberto I think). Storm remnants parked on the GA/AL border for 2 weeks. Six hundred dams broke and the river thru town became over a mile wide. We were mucking out a church on the top of a hill. A road ran from the church, down the long hill to the river. The road was lined with homes that had been fully submerged for 2 weeks.