Comment by unethical_ban | Hacker News Reader

Comment by unethical_ban | Hacker News Reader

It's nothing new to talk about, but rating a hurricane's destructive force on windspeed alone is sub-optimal.

On the other side, one-dimensional labels for a storm help convey the severity of it quickly and unambiguously.

Hurricanes have three components IIRC (as someone who lived on the coast a long time): Storm surge flooding, rain flooding, and wind.

Hurricane Ike was a cat2 in 2008, which did significant damage to the Houston coast because of its large storm surge.

Harvey in 2017 was damaging due to its consistent rain over the area as it stalled. Tropical storm Allison in 2001 was similar.

One may argue that wind causes the most acute damage as well as the fastest "change in status" of the three: High winds can topple a tree to block a road instantly, or rip the roof from a house in a flash, or knock down powerlines taking out a neighborhood.

While I'm not against a cat 6 or higher rating existing, for the sake of human communication "cat 5" means "get the hell out of there" already.

Any rating system is going to fail to be actionable until two things happen. 1, structures need to be rated by the level of wind they're able to withstand, and 2, geographic regions need to be categorized by their likelihood of flooding.

As it stands, as a person, you have no way of knowing if you have a cat X capable roof, nor do you know if you're in an area that is likely to flood, or how likely that area is to flood. Until you have a concrete rating system for those things, you'll have more people thinking that "We can just hunker down" when a cat X is barreling down on them than you want.

That sounds like a big bite to take, but, realistically, you can more or less tag existing houses based on when they were built (ie under which revision of the building code were they built) and then use USGS data to determine flood risk. Then, you categorize all of the above by storm, ie, live in a cat 3 area with a cat 4 house? Evacuate if you have a cat 3 storm because it's going to flood. That will also inform localities as to which areas are going to need to be evacuated first, along with which areas are going to need more emergency assistance post-storm so resources can be allocated more efficiently.

We're already kinda sorta accounting for this at the local level, but, codifying the practice allows it to scale and improve over time.

> Hurricane Ike was a cat2 in 2008, which did significant damage to the Houston coast because of its large storm surge.

> Harvey in 2017 was damaging due to its consistent rain over the area as it stalled.

The outsider impression that I took away was that a major reason why Houston got so rekt by a mere Cat 2 hurricane was in large part driven by property developers building communities in low lying areas that the Army Corp of Engineers had designated as "emergency spillways"[1][2]...the Army knew about the risk, the city turned a blind eye, and the devil in the details weren't disclosed to homebuyers.

Perhaps there's more to the story?

> While I'm not against a cat 6 or higher rating existing, for the sake of human communication "cat 5" means "get the hell out of there" already.

I agree, but skipping town isn't always an option even if you wanted to; experienced two such events[3][4] on Guam as a kid.

[1] https://www.nytimes.com/interactive/2018/03/22/us/houston-ha...

[2] https://www.houstonchronicle.com/projects/2021/how-houston-f...

[3] https://en.wikipedia.org/wiki/Typhoon_Omar

[4] https://en.wikipedia.org/wiki/Typhoon_Paka

On the first point, you're correct about Harvey. Several neighborhoods were built in the basin of a flood plain. And lesser examples of such poor planning and drainage are all over Houston. But sometimes it really is storms that stall over the city dropping rain for three days.

To the second point, yeah... My family tried to evac Rita (2005) and got 5 miles in three hours. Turned around, and the storm missed us.

Three years later, my parents stayed for "cat 2" Ike and were trapped in the attic for 12 hours because Galveston Bay had come five feet up our house.

> Storm surge flooding, rain flooding, and wind

I use wind and the speed of the storm directionally as my mental model when thinking about hurricanes. Rain/surge flooding are results of how long the system is over an area.

That said if a storm is a 3+ I’ll leave - driving 3-4 hours is way more enjoyable than trying to sleep with no AC

All models are wrong, but some are useful. Hurricane ratings have proven to be very useful.

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