The average person should not even really pay attention to the category of the storm. That is mostly of scientific concern. It measures the maximum wind speed found at the relatively tiny center of circulation which may or may not have anything to do with how destructive the rest of the storm is hundreds of miles away from the center, as the article points out. That can also depend on things that have nothing to do with the storm itself, such as whether it’s impacting an area with lax building codes that is unprepared for storm surge. People should forget about that scale and focus on what local authorities are saying about the potential danger.
If you live on the coast, following the details of the forecasts and warnings is extremely important. But my experience living a little over 100 miles inland taught me that the hurricane category is a useful predictor to some extent: anything below category 3 would weaken enough on its way inland that it wasn't a higher risk than routine severe thunderstorms, and didn't require any special advance preparations. The winds would merely be coming from a different direction than usual for our area, and only the areas usually prone to flash flooding had to worry about the volume of rain. It's location-specific, but it is possible to usefully distill the local risk profile down to something where the hurricane category tells you whether it's time to start worrying about that storm.
A comparison can be drawn to the scales used for measuring earthquakes. Although the Richter scale is quite common in many parts of the world, in Japan the Shindo scale is primarily used. This measures the local ground shaking intensity, as opposed to the Richter scale which measures the amount of energy released in the quake.
I think you’re in total agreement with the authors of this new system. They’re simply making a new categorization system that is closer to a 1:1 mapping between the classification and what local authorities are saying about potential danger.
It's easier to make the classification a better representation of danger than it is to convince people to ignore the rating and only listen to local authorities.
This article is about replacing the current scale with one that does factor in more than just wind speed. You're right that it's still just a number though.
(a) The final category can never be lower than the
highest hazard-based category;
(b) The TCSS should adequately reflect the case of
high potential risk of two or more hazards. We
consider a hazard of high risk when its respect-
ive category is classified as 3 or higher (equal
to the definition for a Major Hurricane on the
SSHWS). Whenever (at least) two high risk haz-
ards have the same category value and the third
hazard has a lower category value, the final
category should increment the highest hazard-
based category. This implies that a TC scoring a
Category 3 on both wind and storm surge, and
a Category 1 on rainfall, will be classified as a
Category 4.
(c) To warn the general public for an event with
multiple extreme hazards, a high-risk TC can be
classified as a Category 6 when either 1. at least
two of the hazard-based categories are of Cat-
egory 5; or 2. two categories are of Category 4,
and one of Category 5.
Yep.It this did much damage because places so far North East never experienced storm and so they never built with that in mind.
In place that experience this kind of weather more often(some parts of the Caribbean), it would have been business as usual the next day and I speak from experience.
It sounds like under the new ratings, both would be much closer together. It sounds like the water damage caused by Sandy is not articulated in the current rating system. So Sandy might work out to be a 4 or a 5? Not 100% sure of course, but that is my interpretation of the article.
Feels like something similar to the NFPA 704 safety square [0] — maybe they could copy that to mimic a relatively accepted "danger measurement" format.
Also of interest: hypercanes [1], my hurricane-adjacent Interesting Wikipedia Deep Dive, which (according to Wikipedia):
- require ocean temperatures of 120 °F (50 °C)
- have sustained winds of 500 mph (800 km/h)
- have barometric pressures in their centers sufficiently low enough to cause altitude sickness
- may persist for several weeks due to above low pressure
- may be as large as North America or as small as 15 mi (25 km) — Wikipedia has an unhelpful caption about the size of the "average hypercane" (!)
- extend into the upper stratosphere, unlike today's hurricanes (lower stratosphere)
- due to above height, may sufficiently degrade the ozone layer with water vapor to the point of causing (an additional) hazard to planetary life
As a Florida resident and native, I've been telling people for years to brace for a "Goreicane", which is a cat 6 named after Al.
Irma reached +180mph before magically dwindling to a 3 (or weak 4?) just before landfall. By then, we were already without power, so stats were unknown. I made a safety box out of a toolbox into which I stuffed my cat and provisions, as I wore an old motorcycle helmet and combat boots clutching a bugout bag and bottle of courage.
I really didn't expect to do well and had it hit as a super 5, I'd probably not be leaving this silly post.
Your recollection of Irma's intensity is not particularly accurate. It was never anywhere near 180 mph "just before landfall" unless you were in the Leeward Islands on September 6. Irma crossed the Florida Keys on September 10 as a weak category 4, with 130 mph winds, but it didn't dwindle to that weak category 4 status, it intensified to it. When it left Cuba and turned toward Florida, on September 9, it was only a category 2 (and there was nothing magical about why it dwindled to a category 2 — it was because it ran into Cuban terrain). It did weaken a bit, down to a 115 mph Cat 3, between the Keys and it's second landfall in Collier County.
Hurricane Dorian, in 2019, was almost a "Cat 6" kind of experience for Florida. It made landfall in the Bahamas with 185 mph winds and then just parked itself there, barely moving, for 24+ hours, maintaining Cat 5 strength the whole time. If it had done that on Florida's east coast, as it was once forecast to, the economic destruction would have been unbelievable.
I keep meaning to reread Bruce Sterling's Heavy Weather, about a future where the climate is trashed & weather escalates. Amid this, a group of tornado chasers are trying to find the first "F6" class tornado. https://thierstein.net/index.php?view=article&id=355:bruce-s...
Readit News
https://en.wikipedia.org/wiki/Japan_Meteorological_Agency_se...
It's easier to make the classification a better representation of danger than it is to convince people to ignore the rating and only listen to local authorities.
Lax building codes in hurricane prone areas shouldn't exist after Hurricane Andrew in 1992 [0].
And then there was the Trump sharpie incident. [1]
Wind speed is the best metric (that's not corruptible by humans yet) that describes how dangerous a storm is.
[0]: https://www.npr.org/2024/10/15/nx-s1-5151844/tougher-buildin...
[1]: https://en.wikipedia.org/wiki/Hurricane_Dorian%E2%80%93Alaba...
This new rating system uses the old system and 2 new rating categories
(a) The final category can never be lower than the highest hazard-based category;
(b) The TCSS should adequately reflect the case of high potential risk of two or more hazards. We consider a hazard of high risk when its respect- ive category is classified as 3 or higher (equal to the definition for a Major Hurricane on the SSHWS). Whenever (at least) two high risk haz- ards have the same category value and the third hazard has a lower category value, the final category should increment the highest hazard- based category. This implies that a TC scoring a Category 3 on both wind and storm surge, and a Category 1 on rainfall, will be classified as a Category 4.
(c) To warn the general public for an event with multiple extreme hazards, a high-risk TC can be classified as a Category 6 when either 1. at least two of the hazard-based categories are of Cat- egory 5; or 2. two categories are of Category 4, and one of Category 5.
But about 30 years ago, Andrew swept across Florida like a giant roomba, and did a huge amount of damage. It was a cat 5. Wind did most of the damage.
Not sure how they would reconcile these two types of mega-storms.
In place that experience this kind of weather more often(some parts of the Caribbean), it would have been business as usual the next day and I speak from experience.
Maybe something like free energy in thermodynamics?
Dead Comment
Also of interest: hypercanes [1], my hurricane-adjacent Interesting Wikipedia Deep Dive, which (according to Wikipedia):
- require ocean temperatures of 120 °F (50 °C)
- have sustained winds of 500 mph (800 km/h)
- have barometric pressures in their centers sufficiently low enough to cause altitude sickness
- may persist for several weeks due to above low pressure
- may be as large as North America or as small as 15 mi (25 km) — Wikipedia has an unhelpful caption about the size of the "average hypercane" (!)
- extend into the upper stratosphere, unlike today's hurricanes (lower stratosphere)
- due to above height, may sufficiently degrade the ozone layer with water vapor to the point of causing (an additional) hazard to planetary life
[0] https://en.wikipedia.org/wiki/NFPA_704
[1] https://en.wikipedia.org/wiki/Hypercane
Irma reached +180mph before magically dwindling to a 3 (or weak 4?) just before landfall. By then, we were already without power, so stats were unknown. I made a safety box out of a toolbox into which I stuffed my cat and provisions, as I wore an old motorcycle helmet and combat boots clutching a bugout bag and bottle of courage.
I really didn't expect to do well and had it hit as a super 5, I'd probably not be leaving this silly post.
But cat 6 is real. We'll see it soon.
Hurricane Dorian, in 2019, was almost a "Cat 6" kind of experience for Florida. It made landfall in the Bahamas with 185 mph winds and then just parked itself there, barely moving, for 24+ hours, maintaining Cat 5 strength the whole time. If it had done that on Florida's east coast, as it was once forecast to, the economic destruction would have been unbelievable.
Dead Comment
Different extreme weather but fun book.