The current Saffir–Simpson scale rates hurricanes only by wind speed, which can underplay storm surge and inland flooding risks. In 2021, Jennifer Collins and colleagues proposed the Tropical Cyclone Severity Scale, which gives separate 1–5 ratings for wind, storm surge, and rainfall, then combines them into an overall 1–6 risk category. The new approach aims to make hazards clearer for both the public and emergency managers and could change how warnings and preparedness actions are prioritized.
Beyond Winds: New Tropical Cyclone Severity Scale Would Rank Wind, Surge and Rain
The current Saffir–Simpson scale rates hurricanes only by wind speed, which can underplay storm surge and inland flooding risks. In 2021, Jennifer Collins and colleagues proposed the Tropical Cyclone Severity Scale, which gives separate 1–5 ratings for wind, storm surge, and rainfall, then combines them into an overall 1–6 risk category. The new approach aims to make hazards clearer for both the public and emergency managers and could change how warnings and preparedness actions are prioritized.
10:10 AM, 11/19/2025Science
A University of South Florida researcher is part of an international team proposing a more comprehensive way to communicate tropical cyclone hazards. The current Saffir–Simpson scale, developed in the 1970s, rates storms from 1 to 5 solely by maximum sustained wind speed — a method that can obscure other life‑threatening dangers such as storm surge and inland flooding.
In 2021, Jennifer Collins, a USF hurricane researcher, joined colleagues in the Netherlands to design the Tropical Cyclone Severity Scale, which assigns separate 1–5 ratings for three key hazards: wind, storm surge, and rainfall. Those component scores are then combined to produce an overall risk category that ranges from 1 to 6.
How the new scale works
The system evaluates each hazard independently so that a storm with moderate winds but extreme rainfall or surge receives a high risk rating driven by the most dangerous component. By presenting component scores alongside a single aggregated category, the scale aims to make the full spectrum of a cyclone’s threat easier to understand for the public and emergency managers.
Why it matters
Relying only on wind speed can understate the risks of coastal inundation and catastrophic inland flooding. The proposed scale intends to improve preparedness and decision‑making by clarifying which hazards are most severe for a given storm, helping officials target evacuations, resource staging, and public messaging more effectively.
Collins explains that a multi‑metric severity rating could change how warnings are issued and how communities prepare, by making non‑wind hazards as prominent as wind in risk communications.
The Tropical Cyclone Severity Scale is a proposal aimed at improving communication; its adoption would require testing, stakeholder engagement, and possible integration into existing warning systems. Researchers say the next steps include more outreach to emergency managers and the public to refine the approach and ensure it is actionable.
Note: Jennifer Collins and the research team are the primary sources for this proposed scale.