The insurance industry faces significant challenges in covering catastrophic risks, especially as climate change drives more extreme weather events. With soaring premiums and increasing exclusions, the need for an accurate assessment of these risks is more important than ever. The Saffir-Simpson Hurricane Wind Scale has long been a staple for evaluating hurricanes, but in today’s world, its focus on wind alone is proving dangerously incomplete. The real killer, as we’ve seen time and again, is water—through both storm surge and flooding. It’s time to rethink the system, and that starts with refining the way we categorize hurricanes, not just by wind, but by the water-driven threats that cause the most destruction.

Why Wind Is Beatable

Wind-driven storm damage, while dangerous, is something we’ve learned to mitigate. We’ve seen advancements in building codes, structural designs, and roofing systems that can significantly reduce the impact of wind. A great example is FM Data Sheet 1-29 on roof deck securement, which provides detailed guidelines for above-deck roof components designed to withstand extreme wind forces. Building codes, such as those enforced in Miami-Dade, and the use of materials like Lexan windows, show that we’ve engineered many solutions for wind resistance.

Wind can only blow so fast and hard. Sure, it can tear through poorly constructed buildings, but modern engineering has leveled the playing field in many cases. The three little pigs had it right—build strong enough, and you can beat the wind. But no amount of brickwork can hold back the relentless force of water. Storm surge and flooding are the real threats in modern hurricanes, and they’re much harder to insure and predict. Noah and Gilgamesh, despite their best efforts, couldn’t stop a flood, underscoring the relentless, unstoppable nature of water.

The Misleading Nature of the Saffir-Simpson Scale

Here’s where the Saffir-Simpson scale falls short:

1. No Consideration for Storm Surge: The scale doesn’t factor in storm surge, which is responsible for nearly half of all hurricane-related fatalities. Hurricane Sandy (Category 1) and Katrina (Category 3) wreaked havoc not because of their wind speeds but because of the storm surge and flooding that followed.
2. Ignores Rainfall and Flooding Potential: Flooding from prolonged rainfall can be catastrophic, as demonstrated by storms like Hurricane Harvey in 2017. Harvey was only a Category 4 at landfall, but its slow-moving nature caused it to dump over 60 inches of rain in some areas, leading to unprecedented flooding.
3. Storm Duration and Speed: A fast-moving Category 5 hurricane might pass through quickly, limiting its overall damage. On the other hand, a slow-moving Category 1 storm that lingers over an area can drop enough rain to cause catastrophic flooding. The Saffir-Simpson scale does not factor in the duration of the storm, which can drastically alter its impact.
4. Underinsured Flood Risk (Personal and Commercial): Flood coverage is typically excluded from both standard homeowners’ insurance policies and many commercial property policies. When people focus only on wind, they often neglect to purchase the necessary flood insurance, which leaves them catastrophically underinsured. On the commercial side, businesses can be devastated by flooding, but many are not adequately covered due to exclusions or limitations in their policies. This oversight results in massive uninsured losses that can cripple entire communities and industries after a flood-heavy hurricane.

A Better System: Refining the Hurricane Rating System

We need a more comprehensive scale that accounts for not just wind speed, but also storm surge, rainfall potential, and the storm’s movement. Instead of creating a whole new system, I propose refining the current system to honor the victims of devastating storms and ensure their suffering contributes to future safety. Let’s call it the Helene-Flood-Linger Scale—an expanded framework that builds on the Saffir-Simpson scale by introducing additional metrics to reflect the full potential for damage.

The Helene-Flood-Linger Scale would measure:

1. Wind Category (W): Retains the Saffir-Simpson wind speed classification.
2. Flood Risk (F): Rates the storm’s potential for flooding based on projected rainfall and water volume accumulation over a given area.
3. Storm Surge Risk (S): Measures the expected height and extent of storm surge, particularly in coastal regions. This is critical for anticipating the most destructive aspect of a hurricane in terms of fatalities.
4. Duration Modifier (D): Acknowledges how long the storm will impact a region. Slower-moving storms would receive higher scores for this factor, as they allow more time for rainfall accumulation and sustained damage.

Scoring Hurricane Helene and Comparing with a Faster Category 5 Storm

To demonstrate how this refined system works, let’s apply it to Hurricane Helene, which made landfall in Florida on September 26, 2024, and compare it to Hurricane Wilma (2005), a faster-moving Category 5 storm that caused less deadly flooding:

• Hurricane Helene (2024):
  • Wind Category (W): W4 – Helene made landfall as a Category 4 hurricane.
  • Flood Risk (F): F5 – Helene caused catastrophic flooding throughout the Southeast due to prolonged heavy rainfall.
  • Storm Surge Risk (S): S4 – Helene produced severe storm surges in Florida’s Big Bend area, amplified by rising sea levels.
  • Duration Modifier (D): DSlow – The storm lingered, allowing massive rainfall accumulation, which exacerbated flooding far inland.
  • Helene’s score: W4/F5/S4/DSlow
• Hurricane Wilma (2005):
  • Wind Category (W): W5 – Wilma was a Category 5 hurricane at its peak.
  • Flood Risk (F): F2 – Although Wilma caused some flooding, it moved rapidly, reducing the amount of rainfall.
  • Storm Surge Risk (S): S3 – Wilma caused moderate storm surges, but nothing compared to the damage from storm surge in slower storms like Helene.
  • Duration Modifier (D): DFast – Wilma’s quick movement limited the damage caused by rainfall and storm surge.
  • Wilma’s score: W5/F2/S3/DFast

The comparison shows that even though Wilma was a Category 5 hurricane, its faster movement resulted in less severe flooding and storm surge, making it less deadly than Helene, which lingered and caused widespread flooding despite being a lower wind category storm.

Flood: The Uninsurable Elephant in the Room

Flood risk is notoriously underinsured, especially compared to wind damage. While windstorm coverage is a standard part of most homeowners’ and commercial insurance policies, flood insurance is typically excluded unless specifically added through programs like the National Flood Insurance Program (NFIP) or private commercial policies. This has left a vast unaddressed gap in coverage for both individuals and businesses. As the frequency of slow-moving, water-heavy storms increases, this gap will only become more dangerous.

Flooding is inherently more challenging to insure because it impacts larger areas and often leads to total losses for entire communities and businesses. Unlike wind, which affects only certain buildings or regions, floods can inundate entire cities. This widespread, correlated risk makes it difficult for private insurers to spread flood risk effectively, especially in high-risk areas where climate change is increasing the frequency of extreme rainfall events.

Why the Helene-Flood-Linger Scale Matters

The Saffir-Simpson scale’s overemphasis on wind has made it easier for the public—and even insurers—to underappreciate the real threats posed by hurricanes. By refining the current system and adopting the Helene-Flood-Linger approach, we can improve both public safety and insurance preparedness. Here’s why this matters:

• For Insurers: The refined scale would allow more accurate pricing of risks, helping insurers better understand not only wind exposure but also the much greater threat of flooding and storm surge. This could incentivize the adoption of more flood insurance policies, closing the dangerous coverage gap, especially in the commercial sector.
• For Policyholders: A broader understanding of hurricane risk could lead more individuals and businesses to purchase flood insurance, as they will better understand that even a low-category storm can be devastating if it brings heavy rain or storm surge.
• For Risk Management: From a risk management perspective, focusing on water risks over wind is crucial. Flooding is what will continue to gut the southern U.S., and we need better tools to engineer against that risk, as we’ve done with wind through measures like FM’s roof securement standards.

Conclusion: Refining the Approach to Stabilizing Risk

We must move beyond a wind-only assessment of hurricanes and recognize that the real dangers lie in water. The Helene-Flood-Linger Scale offers a more complete and accurate method for assessing hurricane risks. By acknowledging the importance of flood and storm surge, we can better protect both policyholders and insurers.

In conjunction with this, I’ve long advocated for a government-backed catastrophic perils program to help stabilize the insurance markets. This would allow us to spread risk across a broader portfolio of exposures—flood, wildfire, and pandemics included—ensuring that future generations are better protected from the mega risks of our time.

For contact:

Zach Finn, Director of Risk Management (765) 429-5001 | zfinn@henriott.com

For more information about Henriott Group, visit www.henriott.com.

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Grace Pritchett, Communications (765) 838-8610 | gpritchett@henriott.com