Is the 5th category unnecessary?

[AlphaToOmega]

Is the 5th category unnecessary? By this, I mean whether the label "Category V" for hurricanes is unnecessary. To me, it seems like there is little difference between a Category IV and a Category V storm. The impacts of both Category IV and Category V storms are very similar.

On the official website of the NHC, the impacts of Category IV and Category V storms are both described as catastrophic. This is supported by the fact that Category IV and Category V storms are capable of doing immense damage. Looking at the most damaging Atlantic hurricanes, we find:

1. Hurricane Katrina (C5)
2. Hurricane Harvey (C4)
3. Hurricane Maria (C5)
4. Hurricane Irma (C5)
5. Hurricane Sandy (C3)
6. Hurricane Ike (C4)
7. Hurricane Wilma (C5)
8. Hurricane Andrew (C5)
9. Hurricane Ivan (C5)
10. Hurricane Michael (C5)
11. Hurricane Florence (C4)
12. Hurricane Laura (C4)

While the list contains mostly Category V hurricanes, there are many Category IV hurricanes on that list. What is also not mentioned is that Hurricanes Katrina and Harvey caused exactly the same amount of damage; but one is a Category IV, and one is a Category V. This is further supported after looking at the deadliest Atlantic hurricanes:

1. Hurricane "San Marcos" (C3)
2. Hurricane "Sea Islands" (C3)
3. Hurricane "Chenier Caminada" (C4)
4. Hurricane "San Ciriaco" (C4)
5. Hurricane "Galveston" (C4)
6. Hurricane "Monterrey" (C3)
7. Hurricane "Okeechobee" (C5)
8. Hurricane "San Zenon" (C4)
9. Hurricane "Belize" (C4)
10. Hurricane "Cuba" (C4)
11. Hurricane "Central America" (C2)
12. Hurricane "Jérémie" (C1)

Unlike the previous list, the list of the deadliest Atlantic hurricanes contains a mixture of Category V, Category IV, Category III, Category II, and Category I hurricanes. This further supports the notion that Category IV and Category V hurricanes have basically the same impacts.

The fact that there is little difference between a Category IV and a Category V hurricane raises one question: is the 5th category unnecessary? I have made my case that the "Category V" label is unnecessary. I want to see what other people think.

[toad strangler]

"Is the 5th category unnecessary?"

No

[TallyTracker]

One problem with analyzing the category structure this way is that you’re looking purely at peak intensity and destruction. A category 1 hurricane hitting Miami is going to be far more destructive than a Category 4 hitting South Padre Island Texas (like 1999 Hurricane Bret). Most of those storms never made landfall at peak intensity. Harvey was a cat 4 hurricane but did most of it’s destruction as a tropical storm spinning for days over the Houston metro area causing epic flooding. Michael was a Cat 5 but hit a less populated region of the country resulting in a quarter of the damage value.

Having a 5th category is less about the destruction and more for monitoring the climatological patterns. It’s simply a label we have placed on the storm.

[CFLHurricane]

It’s best to think of Cat 5’s as the “other” bin for exceptionally catastrophic tropical cyclones.

[toad strangler]

Cat 5's in my mind are absolutely necessary. The true Cat 5 is significantly different than a Cat 4 in terms of WIND damage potential to infrastructure and history shows this glaringly. We all know a depression can cause similar flooding issues as with any category. So, Cat 5's are for WIND.

[AlphaToOmega]

Cat 5's in my mind are absolutely necessary. The true Cat 5 is significantly different than a Cat 4 in terms of WIND damage potential to infrastructure and history shows this glaringly. We all know a depression can cause similar flooding issues as with any category. So, Cat 5's are for WIND.

Very few buildings can even survive Category IV winds.

[toad strangler]

Cat 5's in my mind are absolutely necessary. The true Cat 5 is significantly different than a Cat 4 in terms of WIND damage potential to infrastructure and history shows this glaringly. We all know a depression can cause similar flooding issues as with any category. So, Cat 5's are for WIND.

Very few buildings can even survive Category IV winds.

Not true. Especially in FL where the modern BASE building code demands construction not only withstand the design pressures brought on by these winds (Cat 4) but also be HABITABLE afterwards. This is what I do every day for the last 32 years Many people are going to be surprised the next time a major comes through the FL peninsula. Evidence of this was seen in Mexico Beach with new construction in the path of Cat 5 powerhouse Michael.

[HurricaneEnzo]

I'm good with there being a category 5. The way the scale is designed there is going to be some 'overlap' in categories. Is a 110mph Cat 2 any less damaging than a 115mph Cat 3? We know that there are a lot of factors other than windspeed that come into play but everything else being equal no you wouldn't be able to tell any difference at all. The scale in general is kind of dated. Honestly I'm curious to see how much longer this scale remains the 'go to'. While nothing will ever be perfect I'm sure that all the awesome people in the meteorology field could come up with something that is more representative of storm potential.

[Shell Mound]

Cat 5's in my mind are absolutely necessary. The true Cat 5 is significantly different than a Cat 4 in terms of WIND damage potential to infrastructure and history shows this glaringly. We all know a depression can cause similar flooding issues as with any category. So, Cat 5's are for WIND.

Very few buildings can even survive Category IV winds.

Not true. Especially in FL where the modern BASE building code demands construction not only withstand the design pressures brought on by these winds (Cat 4) but also be HABITABLE afterwards. This is what I do every day for the last 32 years Many people are going to be surprised the next time a major comes through the FL peninsula. Evidence of this was seen in Mexico Beach with new construction in the path of Cat 5 powerhouse Michael.

In South Florida many older structures that encountered the northern eyewall of Andrew, even on the immediate shoreline, survived with only cosmetic damage. A good example is the Deering Estate at Cutler. The estate experienced borderline Category-4/-5 maximum sustained winds during Andrew’s passage, but most of the damage was from the large storm tide of up to 16.9 ft ASL that crested at the nearby Burger King headquarters. During the 1926 Miami hurricane most high-rise construction survived Cat-5 gusts, but large structures did collapse due to erosion and waves, principally on the Atlantic shoreline. As has been mentioned previously, structures built prior to 1965 and after 1992 in South Florida should withstand major-hurricane winds quite well, but storm tides and especially waves could present major issues, especially to structures built between 1965 and 1992 (see the recent Surfside incident).

[DestinHurricane]

No. When you look at the recent hurricane landfalls on the CONUS, you have storms like Charley, Laura, and Harvey which are very damaging. Then you have Andrew and Michael which are on another level. Once you get to around 160mph it starts to leave only the concrete, most well built buildings. Additionally, assessing tree damage from cat 4 to cat 5 can be different. Cat 5 is really when you start to see debarking hardwood trees.

[AlphaToOmega]

While there might be SOME difference between a Category VI and V, those differences are quite minor in the grand scheme of things. The fact that it is common for Category IV storms to cause as much damage and as many deaths as Category V storms should say something. What matters is the large-scale impacts, and there is not much difference in terms of large-scale impacts.

[Stormybajan]

While there might be SOME difference between a Category VI and V, those differences are quite minor in the grand scheme of things. The fact that it is common for Category IV storms to cause as much damage and as many deaths as Category V storms should say something. What matters is the large-scale impacts, and there is not much difference in terms of large-scale impacts.

I am 100% sure if we compared the damage from a 130 mph Category 4 Hurricane and a 160 mph Category 5 Hurricane there would be a difference. A category 4 as you said is still extremely powerful and would be a widespread disaster but category 5 winds are just complete devastation and destruction

[tolakram]

While there might be SOME difference between a Category VI and V, those differences are quite minor in the grand scheme of things. The fact that it is common for Category IV storms to cause as much damage and as many deaths as Category V storms should say something. What matters is the large-scale impacts, and there is not much difference in terms of large-scale impacts.

Where are you getting this information? Research has shown the varying levels of damage, that's how the Saffir Simpson was created.

[AlphaToOmega]

While there might be SOME difference between a Category VI and V, those differences are quite minor in the grand scheme of things. The fact that it is common for Category IV storms to cause as much damage and as many deaths as Category V storms should say something. What matters is the large-scale impacts, and there is not much difference in terms of large-scale impacts.

Where are you getting this information? Research has shown the varying levels of damage, that's how the Saffir Simpson was created.

Here:

Looking at the most damaging Atlantic hurricanes, we find:

Hurricane Katrina (C5)
Hurricane Harvey (C4)
Hurricane Maria (C5)
Hurricane Irma (C5)
Hurricane Sandy (C3)
Hurricane Ike (C4)
Hurricane Wilma (C5)
Hurricane Andrew (C5)
Hurricane Ivan (C5)
Hurricane Michael (C5)
Hurricane Florence (C4)
Hurricane Laura (C4)

The list is shared between Category IV and Category V storms (with one Category III storm in there: Hurricane Sandy). When I talk about impacts, I mean deaths and damages. Maybe my data is a bit skewed because most of the Category IVs were high-end Category IV storms.

[HurricaneEnzo]

Will you be able to tell the difference between a 155mph Cat 4 and a 160mph Cat 5? Probably not.

Will you be able to tell a difference between a 155mph Cat 4 and a Maria, Irma, Dorian? I would think absolutely. As I said there is going to be some overlap there when you are talking a couple of mph but these high level Cat 5s are definitely different monsters even when compared to a Max Cat 4.

[tolakram]

Here:
Looking at the most damaging Atlantic hurricanes, we find:


The list is shared between Category IV and Category V storms (with one Category III storm in there: Hurricane Sandy). When I talk about impacts, I mean deaths and damages. Maybe my data is a bit skewed because most of the Category IVs were high-end Category IV storms.

I'm asking where are you getting the information about damage vs wind speed? There's no information there. You want to know if cat 5 is unneeded, I want to know based on what? Research has shown clearly that cat 5 winds are much more damaging than cat 4, but of course a high end cat 4 vs a low end cat 5 is going to be nearly identical. You have to set the scale somewhere.

[AtlanticWind]

On your list comparing Katrina and Harvey , Katrina was not a cat 5 on landfall

[AtlanticWind]

Wilma also didnt landfall as a cat 5

[Category5Kaiju]

If the Saffir Simpson scale were to max out at Category 4 and eliminate a Category 5 bar, then it would be inherently confusing as we would basically have a 130 mph Harvey and a 185 mph Dorian, for example, put into the same group. Sure, the lines may blur between a 155 mph and a 160 mph storm, but there is no denial that a 155 mph and a 185 mph storm do vastly different damage. In this sense, I do think a Category 5 storm is necessary just to emphasize how powerful the storm's winds are, but the Saffir Simpson scale should only be used as a measure of windspeed rather than a surefire indicator of other elements such as flooding or surge potential. I think people get caught up with windspeed a little too much as we have seen in the past how storms like TS Harvey or Cat 1 Florence proved to be a massive flooding disaster while Cat 2 Ike produced one of the highest storm surges on record in the US.

[St0rmTh0r]

The categories 1-5 should be used for the amount of destruction a storm causes after the storm has passed. For example Katrina category 5 damage. So it should be labeled as a cat 5. Would you classify Allison as a category 5 tropical storm? I would, so this is how they should go about it.