What makes Hurricane Melissa such a dangerous storm

A very powerful hurricane has reached Jamaica and is expected to be the strongest storm to hit the Caribbean island in modern history.

Hurricane Melissa, now a Category 5 storm, hit the island’s south coast with maximum sustained winds of 295km/h (185mph); The strongest wind seen on Earth so far this year.

These speeds are above those of Hurricane Katrina in 2005, one of the worst storms in U.S. history.

For a nation living on the front lines of a changing climate, the threat is grave.

So why is this particular hurricane so dangerous?

Tropical Storm Melissa formed last Tuesday before rapidly strengthening as it moved westward across the Caribbean.

A hurricane forms when warm, moist air rises from the ocean surface and forms a rotating system of clouds and storms. At the center, the air sinks to form the eye, a calm, cloudless region surrounded by a wall of high winds and rain, known as the eye wall.

Melissa’s origins can be traced back to mid-October storms off the coast of West Africa. It had reached tropical storm strength on October 21 and became a Category 4 monster, churning in the Caribbean Sea on October 26.

Ocean temperatures in the Caribbean are unusually high this year, and hurricanes are fueled by this layer of warm water. These conditions allowed Melissa to rapidly escalate.

“The ocean is warmer and the atmosphere is warmer and more humid because [climate change],” says Brian McNoldy, a senior research associate at the University of Miami.

“So this tips the scale in favor of things like rapid densification [where wind speeds increase very quickly]higher peak intensity and increased precipitation.”

Melissa is considered one of the strongest storms in the Atlantic this century.

For Jamaicans, comparisons to past storms are chilling. If it hits Jamaica at close to full strength, it could dwarf any storm the island has experienced before. Gilbert’s last direct hit in 1988 was a Category 3. It destroyed thousands of homes and killed 49 people. Dean in 2007 and Beryl in 2024 approached each other, but neither could match Melissa’s power.

The storm’s central air pressure dropped to 892 millibars, below Hurricane Katrina’s 902 mb, as of the National Hurricane Center’s advisory Tuesday morning local time. The lower the pressure, the stronger the winds; making this one of the most powerful systems ever formed in the Atlantic.

Hurricane Katrina, which hit New Orleans in 2005, killed 1,392 people and caused damage estimated at $125 billion (£94 billion).

“This will be the strongest hurricane ever hit [Jamaica]Dr. D., a research software engineer at the Environmental Change Institute at the University of Oxford. “At least in the records we have,” Fred Thomas told the BBC.

The storm was blamed for four deaths in Haiti and the Dominican Republic. Jamaica’s health minister said Monday that three people have died on the island as it prepares for an approaching storm.

Melissa strengthened particularly quickly, driven by very warm waters in the Caribbean, about one to two degrees above average.

Dr. Dr., research fellow in extreme climate conditions at the University of Bristol. “There was a perfect storm of conditions that led to the tremendous strength of Hurricane Melissa,” Leanne Archer said.

Although the wind speed is surprisingly high, the movement of the storm is quite slow. Melissa was crawling westward at about 3 mph on Tuesday; this was slower than a human’s walking speed.

Meteorologists warn that this lethargy could be disastrous; because this means a hurricane can dump rain on a single location for days, aggravating flooding.

When hurricanes stall, they linger in an area much longer than normal, causing repeated waves of rain, flooding and wind damage.

One of the most famous examples of this is Hurricane Harvey, which hit Houston in the USA in 2017. Harvey dropped 100 cm of rain in just three days, causing catastrophic flooding.

The US National Hurricane Center warned that 38 to 76 cm of precipitation could occur in Jamaica, and up to one meter of precipitation could occur in some mountainous areas.

Storm waves of up to four meters are possible, especially on the south and east coasts of the island. Low-lying parishes such as Clarendon and St Catherine are at risk of flash flooding not only from rainfall but also from flooding flowing down from the Blue Mountains.

“Imagine one meter of rainfall landing on an entire catchment and then being channeled into a river network. By the time it reaches the lower parts of the drainage network, that will be meters of flooding. So I would imagine the flooding would probably lead to a huge loss of life,” said Dr Thomas, who visited Jamaica earlier this year.

Some research suggests that hurricanes are generally moving slower than before. This means more storms like Melissa could stall rather than sweep across the land they hit.

Some scientists believe this may be related to how climate change affects circulation patterns in our atmosphere, but this is far from certain and natural variability may also play a role.

Jamaican Prime Minister Andrew Holness has already warned that “no infrastructure can withstand Category 5”.

Dr Thomas largely agreed, but explained that most new buildings in Jamaica are made of reinforced concrete, as required by national building codes.

“Anything built to this rule has to be pretty wind-strong, but wind only has one effect,” he said.

“The scary thing about Melissa is not just the wind, but also the rain and storm. You could completely flood your entire ground floor and then part of the first floor.”

He said construction is more robust in major cities such as Kingston and Montego Bay, but in rural and hillside areas “there is more local architecture.” [some things built from wood] not larger, concrete-type buildings.” These will be much worse off.

“This hurricane will hit Jamaica hard,” says Kerry Emanuel, professor emeritus of atmospheric science at the Massachusetts Institute of Technology.

Kingston-based architect and conservationist Dr. Patricia Green told the BBC that Jamaica was “not prepared to deal effectively” with major storms. He recalled how “a few hours of rain” in September caused “massive flooding” in the capital and exposed deep weaknesses in urban planning.

He criticized the increase in high-rise construction in “areas of the city that should have flowing water” and said that these were dragging into flood areas “which have never experienced floods before”.

As a low-lying island country, it is particularly exposed to storms. According to Jamaican government data, approximately 70% of the population lives in coastal areas.

As with extreme weather, poor communities are expected to be hit the worst.

“This is one of the worst-case scenarios that you prepare for but hope never happens,” says Hannah Cloke, professor of hydrology at the University of Reading.

“The entire country will be deeply and lastingly scarred by this storm monster. For those affected, it will be a long and grueling recovery.”

Tourism is another concern. Jamaica’s major resorts are largely made of concrete, but their durability has never been tested by winds of this magnitude.

Other parts of the country’s infrastructure are more at risk and power outages are expected. Dr Thomas said: “The grid is likely to knock out areas before the worst storm. But then you have poles and lines knocked down by debris and trees. The problem is often not the wind itself, but what the wind picks up.”

Beyond buildings, the storm threatens Jamaica’s electricity, water and transportation networks. Fallen trees and flying debris are expected to knock down power lines. Flooding can overwhelm sewer systems and contaminate water supplies. Landslides are likely to cut off mountain roads, isolating rural communities.

Dr Green said modern architectural trends were worsening durability and the switch from traditional slatted jalousie windows to fixed glazing could leave buildings more exposed. Sealed panels prevent air from passing through, increasing pressure inside and making walls and roofs more likely to collapse when storms hit.

He added that the most vulnerable are poorer communities, especially those living along river banks and valleys. Dr. Green says it’s a “historical, colonial issue” that dates back to emancipation, when formerly enslaved people were given marginal land. Many of these families have lived there for generations without affordable alternatives or secure land titles, he said.

Dr Thomas drew particular attention to Port Royal, a small fishing village in Kingston, which is considered one of the most vulnerable communities to the hurricane and is on the mandatory evacuation list.

He visited in February and explained: “It’s a long stretch of land, and it’s extremely exposed, a seven or eight-mile journey to the mainland, so it can be cut easily.”

The ripple effect of any failure can be huge: “Power goes out, then telecommunications goes out. Hospitals have support for a while, but often it’s not enough. Plus the airport is closed, meaning help can’t arrive quickly.”

With airports closed, supply chains disrupted and aid flights grounded, recovery could take months even after the storm has passed.