Measuring the power of destruction with hurricane categories
Hurricanes of all strengths can be devastating.
All eyes are on Hurricane Melissa, the strongest storm to ever hit the Caribbean.
It made landfall on Tuesday in Jamaica as a powerful Category 5 storm, with sustained winds of 298 kilometres per hour.
That was strong enough to tear the roofs off buildings, bring down trees and powerlines, and cause violent storm surges.
How hurricanes are rated
The strength is measured by the Saffir-Simpson Hurricane Wind Scale, which rates hurricanes from Category 1 to 5 based on wind speed.
These ratings are used to forecast wind intensity, potential damage, and threats to human safety. While it does not take into account storm surge, floods, or tornadoes, the scale does account for a hurricane’s maximum sustained wind speed, which can strengthen or weaken throughout an event.
We’re already seeing this with Melissa, which hit Jamaica as a Category 5 storm on Tuesday. By Wednesday, it had weakened to a Category 3 storm as it made landfall in Cuba.
Here’s a look at the damage associated with different ratings.
CATEGORY 1
Category 1 storms are the most common types of hurricanes but, with sustained winds between 119 and 153 kilometres per hour, they can still be very dangerous.
Wind this strong can tear the siding off homes, down trees and cause widespread power outages. People or animals caught outside during a Category 1 storm could face severe injury or death.
Considered "very dangerous," Category 1 storms have sustained wind speeds of 74-95 mph (119-153 kph) and can deface home exteriors, snap tree branches, and cause days-long power outages. People, livestock, and pets face some risk of injury or death.
Example of Category 1 hurricane impacts: Hurricane Franklin | Sinaloa, Mexico | August 2017
CATEGORY 2
Classified as “extremely dangerous” Category 2 storms pack sustained winds between 154 and 177 kilometres per hour and are capable of causing major damage to homes and uprooting trees that can cause road blockages.
Example of Category 2 hurricane impacts: Hurricane Delta | South Central U.S. | October 2020
CATEGORY 3
Category 3 storms pose an extreme risk to safety, with sustained winds up to 208 kilometres per hour.
While evacuations can be ordered at any strength, Category 3 and up is where you’re most likely to see mandatory evacuation orders or state of emergency declarations.
A storm this strong can blow the roof of a building straight off and cause major infrastructure damage that could take years to repair.
Example of Category 3 storm impacts: Hurricane Erick | Southern Mexico | June 2025
CATEGORY 4
A Category 4 storm will almost certainly cause catastrophic damage to infrastructure and homes, lead to widespread power outages, water shortages, and road closures, and could render communities uninhabitable for weeks. With winds between 209 and 251 kilometres per hour, it’s hard to overstate the risk associated with the types of systems.
Example of Category 4 storm impacts: Hurricane Helene | Across Florida | September 2024
CATEGORY 5
At landfall, Hurricane Melissa was packing sustained winds of a mind-boggling 298 kilometres per hour. We’re seeing the aftermath of that catastrophic event now: Widespread devastation, transportation upheaval, isolated communities, and extensive power and communication outages.
As Jamaica cleans up from this unprecedented storm, it’s important to note that Jamaican authorities worked hard to mitigate damage ahead of the storm by closing airports, issuing evacuation alerts, setting up shelters, and providing constant updates to the public, thereby limiting loss of life.