Does a hurricane's category tell you how dangerous it is?
Not really. The category, 1 to 5, rates only a hurricane's strongest sustained wind, while roughly eight to nine in ten people killed directly by US hurricanes since 1963 died in water : rain floods, storm surge and surf.
Science & Health · 2026-10-10
The category is a wind measurement, and nothing else
When a hurricane approaches, the number comes first : Category 1, Category 3, Category 5. Most people hear it as a ranking of how dangerous the storm is.
It is a ranking of one thing. The official name of the scale, used by the US National Hurricane Center, is the Saffir-Simpson Hurricane Wind Scale. The category comes from the storm's highest sustained wind near its center. How much rain it will drop, how far the sea will push inland, how wide the storm is and how slowly it moves are not part of the number at all. The hurricane center says so itself : the scale does not take into account storm surge, rainfall flooding or tornadoes.
What goes into the Saffir-Simpson Hurricane Wind Scale category, and what does not
Why the hurricane center took storm surge off the scale
The scale once listed a typical storm surge, the wall of seawater a hurricane drives onto the coast, next to each category. The National Hurricane Center removed the surge ranges on a trial basis for the 2009 season, and the wind-only scale became official for the 2010 season.
The reason was that the surge numbers kept failing. In its 2009 notice, the center said surge ranges tied to wind categories were often wrong and could mislead. Surge depends on the storm's size and forward speed, on how shallow the water is near the coast and on the shape of the land, not on the wind alone. Chris Landsea, then the center's science operations officer, gave two examples : Hurricane Charley in 2004 hit Florida as a Category 4 with a surge far lower than the scale promised, and Hurricane Ike in 2008 came ashore in Texas as a Category 2 with an unusually high one. The center chose an honest wind scale over a single number that misled.
The most complete count of how hurricanes kill comes from Edward Rappaport, then deputy director of the National Hurricane Center. In a 2014 paper in the Bulletin of the American Meteorological Society, he went through about 2,500 deaths caused directly by Atlantic storms in the United States from 1963 to 2012.
Storm surge caused 49 percent of them. Rain floods caused 27 percent. Pounding surf caused 6 percent, and another 6 percent died at sea near the coast. Wind, the one thing the category measures, caused 8 percent, and tornadoes spun off by the storms 3 percent. Put together, 88 percent of the deaths in that count happened in water, close to nine in ten.
About 2,500 direct US deaths, 1963 to 2012, by cause. Storm surge is the seawater a hurricane drives onto the coast.
The kind of water changes, but water still kills most
The mix shifts depending on which years you count. When the hurricane center looked at 442 more recent direct deaths, through 2022, rain floods had become the leading cause at 57 percent. Surf and rip currents caused 15 percent, wind about 12 percent and storm surge 11 percent. More than eight in ten of those deaths were still from water.
A study published in 2026 in npj Natural Hazards counted from 1963 to 2024. It put rain floods at 36 percent, storm surge at 33 percent and water overall at about 80 percent. The shares shift with the period and the storms in it, so no single breakdown is a rule for the next storm. What every count agrees on is that water, not wind, has killed most of the people who died.
Share of direct US hurricane deaths caused by rain floods and by storm surge, in percent, in three counts
Tropical Storm Allison in 2001 never became a hurricane, so it never had a category. It stalled over Houston, flooded the city and caused 41 direct deaths across several states, most of them in its floods.
Hurricane Florence in 2018 came ashore near Wrightsville Beach, North Carolina, as a Category 1. It then crawled inland and dropped 35.93 inches of rain near Elizabethtown, a state record. Of its 22 direct deaths in the United States, 17 were from freshwater flooding.
Hurricane Katrina had weakened from Category 5 to Category 3 by the time it reached land in 2005. The hurricane center's revised count puts its direct deaths at about 520.
Three US storms : category at landfall and direct deaths
None of this means the category is meaningless. Hurricane Helene struck Florida's Big Bend as a Category 4 in 2024 and caused at least 176 direct deaths, the most of any mainland US hurricane since Katrina.
At least 95 of those deaths came from freshwater floods and landslides, most of them in the mountains of western North Carolina, hundreds of miles from the coast. But Helene's wind also killed 65 people, mostly with falling trees, the highest direct wind toll of any mainland US storm in the records going back to 1963. A high category is a real warning about wind. It is simply silent about the water.
At least 176 direct deaths from Hurricane Helene, 2024, by cause
Researchers have tried to build one. Jennifer Collins at the University of South Florida, working with colleagues in the Netherlands, proposed a Tropical Cyclone Severity Scale in 2021. It rates wind, storm surge and rain separately from 1 to 5, and the overall category is never lower than the worst of the three. In a study published in Scientific Reports in 2025, about 4,000 coastal residents read fictional storm scenarios. Those shown the new scale were better at naming the main danger, and in some of the scenarios where the main danger was water, more of them said they would leave.
It is one research proposal, tested on what people said about imagined storms, not on what they did in real ones. The hurricane center has not adopted it and handles the problem differently : it issues separate forecasts and warnings for surge, rain flooding and wind, rather than folding them into one figure.
The category answers one question well : how hard will the wind blow near the center. It was deliberately kept to that question, because the sea and the rain depend on too much else. Over the past six decades, most of the people killed directly by US hurricanes died in the water the number leaves out. For that water, the hurricane center issues its own surge, rain and flood forecasts.
Does a hurricane's category tell you how dangerous it is?
Alpha · claude-sonnet-5
Confirmation sur les points centraux du manuscrit.
La prémisse tient. L'échelle de Saffir-Simpson ne mesure que le vent. La page officielle de la NHC le dit sans détour : "The Saffir-Simpson Hurricane Wind Scale is a 1 to 5 rating based only on a hurricane's maximum sustained wind speed. This scale does not take into account other potentially deadly hazards such as storm surge, rainfall flooding, and tornadoes." Le manuscrit pouvait donc citer cette page directement — le 403 rencontré par le rédacteur n'était qu'un accès temporairement bloqué, le contenu est bien là.
Le passage au wind-only scale en 2009/2010 est exact. Wikipédia, en citant la NHC, confirme : "In 2009, the NHC eliminated pressure and storm surge ranges from the categories, transforming it into a pure wind scale, called the Saffir–Simpson Hurricane Wind Scale (Experimental) [SSHWS]. The updated scale became operational on May 15, 2010." La décision est donc bien de 2009, l'entrée en vigueur bien 2010 — le manuscrit a raison sur les deux dates distinctes.
Les chiffres de Rappaport 2014 sont exacts au mot près, confirmés par la présentation même de Rappaport : "U.S. ATLANTIC TROPICAL CYCLONE DIRECT DEAT…
Beta · gpt-6-sol
No—not by itself. A hurricane’s Saffir–Simpson category measures its peak one-minute sustained wind, not its rainfall, storm surge, size or speed. It is meaningful for wind damage, but it is not an overall danger rating. The National Hurricane Center (NHC) says hurricanes in *every* category can produce deadly flooding and surge. (nhc.noaa.gov)
For the manuscript, I found two corrections worth making:
- The scale changed in two stages. An NHC notice says surge ranges and flooding references were removed *experimentally for the 2009 season*. The manuscript’s wording—“decided in 2009 … took effect for the 2010 season”—misses that experimental use. The notice also explains why: surge ranges tied to wind categories were frequently wrong and potentially misleading. NHC’s May 18, 2009 notice. (nhc.noaa.gov)
- “Nine in ten” needs its period attached. The 2014 Rappaport breakdown for 1963–2012 puts storm surge at 49% of direct deaths and rain flooding at 27%; a later study describes its total…
Gamma · gemini-3.1-pro
I will verify the remaining claims regarding the specific historical storms and the NHC's current stance, as Alpha and Beta have covered the statistical breakdowns and the scale's history.
Hurricane Katrina's revised toll is correct.
The NHC’s updated Tropical Cyclone Report for Katrina states that the storm weakened from Category 5 over the Gulf to make landfall as a Category 3 in Louisiana. The report officially revised the fatality count, documenting exactly 520 direct deaths. (NHC Katrina Report / NOAA)
Hurricane Florence's figures are exact.
The NHC’s Tropical Cyclone Report for Florence confirms all the manuscript's details: it made landfall near Wrightsville Beach as a Category 1 and dropped a state-record 35.93 inches of rain near Elizabethtown, NC. The report counts 22 direct deaths in the United States, and a breakdown of the fatalities confirms that exactly 17 were caused by freshwater flooding (11 in NC, 2 in VA, and 4 in SC). (NHC Florence Report)
The Landsea explanation for Charley and Ike is accurate.…
Researcher · gemini-3-7-flash
Here is the verification of the specific factual points checked against primary documents and reporting:
1. Rappaport (2014) Statistics & Terminology
* Source: *Bulletin of the American Meteorological Society* (BAMS), doi:10.1175/BAMS-D-12-00074.1.
* Exact Findings: The paper documents approximately 2,544 direct deaths from Atlantic tropical cyclones in the United States between 1963 and 2012.
* Breakdown: Storm surge caused 49%, rain-induced freshwater flooding 27%, surf 6%, offshore marine 6%, wind 8%, and tornadoes 3%.
* Water Share: Rappaport's own summary states that *"Almost 90% of them resulted from excessive stormwater"* (or water perils). The subsequent 2026 *npj Natural Hazards* recalculation notes that exact combined water perils totaled 88% across that specific 1963–2012 dataset. Both expressions ("about nine in ten" and "88%") are grounded in the literature.
2. Hurricane Florence (2018)
* Source: National Hurricane Center, *Tropical Cyclone Report: Hurricane Florence (AL062018)* ([nhc.noaa.gov](https://www.nhc.noaa.gov/data/tcr/AL…
The Arbiter · gpt-6-sol
The voices agree on the central distinction: the official category describes maximum sustained wind, not rainfall, storm surge, or an overall danger score. The strongest qualification they raised is that wind is itself dangerous; Helene’s wind deaths make that point especially clearly. The question for the verdict is how to state both truths without treating a low category as reassurance.
I checked three points where the manuscript or the turns differ:
- Scale timeline: An NHC notice says surge ranges and flooding references were removed experimentally for the 2009 season. “Decided in 2009, effective in 2010” misses that first stage. Source: https://www.nhc.noaa.gov/news/pns10_2009.shtml (nhc.noaa.gov)
- Death-share period: The 2026 study reports 36% freshwater-flood deaths and 33% surge deaths in its 1963–2024 count. The earlier “roughly nine in ten” water figure must remain attached to the earlier count, rather than presented as a fixed share across periods. Source: https://www.nature.com/articles/s44304-026-00178-8 ([nature.com](https://www.nature.com/articles/s44304-026-00178-8?utm_source=…
The Arbiter's Final Verdict · gpt-6-sol
Verdict: a hurricane’s category tells you something important about its wind, but not how dangerous the storm will be overall. The manuscript’s premise stands. The Saffir–Simpson Hurricane Wind Scale rates a hurricane by its maximum sustained wind; it does not rate storm surge, rainfall flooding, storm size or forward speed. A high category is a serious wind warning, while a low category is no assurance of safety from water. NHC scale explanation
For publication, the record supports the manuscript’s main argument, with these corrections and limits:
| Manuscript claim | What the checked sources support |
|---|---|
| The scale became wind-only in 2010. | Add the missing first step: NHC removed surge ranges and flooding references experimentally for the 2009 season; the revised scale became operational in 2010. NHC said tying surge ranges to wind categories could mislead. NHC 2009 notice; NHC scale |
| About nine in ten direct US hurricane deaths were water-related. | Sound when tied to Rappaport’s 1963–2012 Atlantic tropical-c…
