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Last I heard from weather people, cat 6 is not really needed, wonder if that changed recently.

With NOAA's cuts, the only way I think cat 6 will be add is Trump wants to be the one to create that level and scientists state it is not really needed :)

They're just trying to compete with Ethernet.
It’s my understanding that “category 5” means “total destruction”, which is why this hasn’t been done in the past. However if it helps to get the point across about climate change, it would be helpful for marketing purposes.
Power creep. They should just buff cat 1 and 2.
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.
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.

But cat 6 is real. We'll see it soon.

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

[0] https://en.wikipedia.org/wiki/NFPA_704

[1] https://en.wikipedia.org/wiki/Hypercane

Up here, Sandy was a cat 2 or 3, but caused 70 billion dollars’ worth of damage, and killed a couple hundred people. Water did most of that damage.

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.

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I believe this is the real paper for those curious: https://pure.lib.usf.edu/ws/portalfiles/portal/40758246/Adeq...

This new rating system uses the old system and 2 new rating categories

   Wind (from old system, 1min sustained speeds)
   Cat 1: 33–42 m/s (~74–95 mph)
   Cat 2: 43–49 m/s (~96–110 mph)
   Cat 3: 50–58 m/s (~111–129 mph)
   Cat 4: 59–69 m/s (~130–156 mph)
   Cat 5: >70 m/s   (>157 mph)
   
   Storm surge (peak surge height above tide)
   Cat 1: 0.75–1.54 m
   Cat 2: 1.55–2.34 m
   Cat 3: 2.35–3.14 m
   Cat 4: 3.15–3.99 m
   Cat 5: >4.00 m
   
   Accumulated rainfall (event total)
   Cat 1: 100–262 mm
   Cat 2: 263–425 mm
   Cat 3: 426–588 mm
   Cat 4: 589–749 mm
   Cat 5: >750 mm
And the following criteria:

(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.

The National Hurricane Center has figured out pretty well how to depict hurricane danger to the public, but a lot of people don't bother to pay attention to it and go for noisy sources instead. I think it's a good example for how to prioritize important information in general. Every few hours, they put out a selection of graphics:

- A "Key messages" graphic with 2-4 bullet points about what is going on, what is predicted to happen, and specific dangers to look out for. The tone of the text is carefully adjusted for how life-threatening the situation is. This graphic also includes a copy of the two most important visualizations on the right. (Example: https://www.nhc.noaa.gov/archive/2024/HELENE_graphics.php?pr...)

- A peak storm surge graphic showing predicted coastal inundation and destructive wave action (Example: https://www.nhc.noaa.gov/archive/2024/HELENE_graphics.php?pr...)

- A cone to depict the range of predictions for where the hurricane could go, ideally without a confusing line drawn in the center prediction (Example: https://www.nhc.noaa.gov/archive/2024/HELENE_graphics.php?pr...) Arguably this could be replaced with a spaghetti model map, but these can be just as confusing for those unaware of how predictions are depicted.

- A map of the most likely arrival time for hurricane force winds (Example: https://www.nhc.noaa.gov/archive/2024/HELENE_graphics.php?pr...)

- After the main risks are over, a map of continued flash flood and river flooding risk (Example: https://www.usatoday.com/gcdn/authoring/authoring-images/202...)

- A no-frills ad-free weather report livestreamed to social media, so you can gauge how much the pros at the very top level of hurricane meteorology are freaking out about it (Example: https://www.youtube.com/watch?v=GFL-nbFs2Xs)

- A few other graphics and data dumps primarily intended for meteorologists, local officials, and nerds