mark pointing,Climate reporter
![NOAA/Getty Images Satellite image of Hurricane Lee over the Atlantic Ocean](https://ichef.bbci.co.uk/news/480/cpsprodpb/a9e4/live/885c5cb0-1841-11ef-b29c-db4f2723162a.jpg.webp)
NOAA, the National Weather Service, warned that as many as seven Category 3 hurricanes could occur in the North Atlantic this year, more than double the usual number.
Typically, we expect to see three major hurricanes per season.
As many as 13 Category 1 or higher Atlantic hurricanes are expected to occur between June and November.
Record-high sea surface temperatures are partly to blame, as are changes in regional weather patterns.
There is no evidence that climate change is causing more hurricanes, but the most powerful hurricanes are becoming more likely to occur and producing more rainfall.
“this [hurricane] NOAA Administrator Rick Spinrad said at a news conference that he expects this season to be special.
that much Recent weakening of El Niño weather pattern – and a likely transition to La Niña conditions later this year – creating more favorable atmospheric conditions for storms in the Atlantic.
Unlike the Atlantic, NOAA has already “Below Normal” Hurricane Season In the Central Pacific region, La Niña has the opposite effect.
On average, the Atlantic Basin, which includes the Atlantic Ocean, the Caribbean Sea, and the Gulf of Mexico, experiences 14 tropical storms a year, of which seven are hurricanes and three are major hurricanes.
A tropical storm becomes a hurricane when it reaches maximum sustained winds of 74 mph (119 km/h). A 'major' hurricane (Category 3 or higher) is one that reaches speeds of at least 111 miles per hour (178 km/h).
NOAA expects a total of 17 to 25 tropical storms to form, of which 8 to 13 could become hurricanes and 4 to 7 could become major storms.
The highest number of major hurricanes in a single Atlantic season was seven in both 2005 and 2020. NOAA's projections suggest 2024 could be close to that.
![Graphic showing the increasing number of Category 3, 4, and 5 hurricanes in the North Atlantic.](https://ichef.bbci.co.uk/news/480/cpsprodpb/9ab0/live/9e475d80-1842-11ef-b5cc-cb8b8c4cef5a.png.webp)
The exact causes of individual storms are complex, but there are two main factors that play into the forecast.
First, there is a potential transition from El Niño to La Niña in the coming months, which could make it easier for these storms to grow.
Second, sea surface temperatures in major hurricane producing areas in the tropical Atlantic are much warmer than usual.
This often means stronger hurricanes. That's because warm water provides more energy for the storm to grow as it moves west.
Ken Graham, director of the National Weather Service, said “everything is in place” for an intense hurricane season.
![This is a map of April sea surface temperatures compared to the long-term average. The tropical Atlantic Ocean is much warmer than usual.](https://ichef.bbci.co.uk/news/480/cpsprodpb/a82d/live/66e7a520-1842-11ef-80aa-699d54c46324.png.webp)
To call attention to how global warming is increasing the likelihood of the most powerful storms occurring; Recent research The possibility of creating a new category 6 level was explored.
It said: “The most powerful tropical cyclone we are currently experiencing is unprecedented and should serve as a warning to the public as to why.” [is] “Warming of the surface ocean due to climate change,” explains study lead author Michael Wehner, senior scientist at Berkeley Earth.
The hurricane category only considers wind speeds. But these storms typically bring other major hazards, such as rainfall and coastal flooding, which are worsened by climate change, NOAA warned.
Warmer air can hold more moisture, increasing the intensity of rainfall.
meantime, storm surge – Short-term sea level rise due to hurricanes is now occurring on a higher base. This is mainly due to higher sea levels as glaciers melt and oceans warm.
“Rising sea levels are increasing the overall depth of flooding, making today’s hurricanes more damaging than storms in previous years,” said Andrew Dessler, a professor of atmospheric sciences at Texas A&M University.
Considering the active forecast, the researchers emphasize the need for the public to be aware of the risks these storms can pose, particularly “rapid intensification events” where hurricane wind speeds can increase very quickly, making them particularly dangerous.
“We are already seeing an overall increase in the fastest rate at which Atlantic hurricanes are strengthening, meaning the hazard risk to coastal communities is already increasing,” explains Andra Garner, assistant professor at Rowan University in the US. .
“It may still be difficult to predict the rapid intensification of the storm, which magnifies the challenges it poses when trying to protect coastal communities.”
Graphics: Erwan Rivault and Muskeen Liddar