Hurricanes Are Growing Larger More Often

Seven hurricanes rapidly intensified in the 2024 Atlantic hurricane season. That's a more common occurrence than it may seem.

What is rapid intensification: Meteorologists define this as an increase in a tropical storm or hurricane's maximum sustained winds of at least 35 mph in 24 hours or less.

Rafael's flex: Rafael, the last storm to explode in 2024, intensified from a tropical storm to Category 3 hurricane as it moved from near Little Cayman Island to western Cuba. That's a change in intensity of 55 mph in just 24 hours.

Weather in your inbox

Forecast Location

Sign Up

By signing up you agree to the Terms & Privacy Policy. Unsubscribe at any time.

(Further beef up your forecast with our detailed, hour-by-hour breakdown for the next 8 days – only available on our Premium Pro experience.)

2024's other rapid intensifiers: Rafael became the seventh hurricane of the 2024 Atlantic hurricane season to rapidly intensify, following Beryl, Helene, Isaac, Kirk, Milton and Oscar.

Beryl went from a tropical depression to the first June Cat. 4 Atlantic Basin hurricane of record in just 48 hours. Milton underwent two separate rapid intensifications: first from a minimal tropical storm to Cat. 1 hurricane, then an incredible 90 mph turbo boost from Cat. 1 to Cat. 5 intensity.

Most major hurricanes rapidly intensify: All five "major" - Category 3 or stronger - hurricanes this season rapidly intensified.

According to a 2016 study, 79% of major hurricanes experience rapid intensification.

In the frenetic 2020 season, 10 of the 13 hurricanes rapidly intensified, particularly Hurricanes Delta, Eta and Iota.

The study also found only 6% of storms that don't rapidly intensify become major hurricanes. None of the four hurricanes of 2024 that did not rapidly intensify - Debby, Ernesto, Francine and Leslie - reached major hurricane status.

Why they explode: Low wind shear but winds that spread apart aloft, plenty of moist air and deep, warm ocean water are favorable for a tropical cyclone to intensify. Also, smaller storms that can concentrate the heating from thunderstorms in a tight core have a better chance of rapid intensification than larger circulations. Such was the case with smaller hurricanes in 2024 such as Oscar and Rafael.

A 2018 NOAA study found various other factors explaining why some hurricanes rapidly intensify while others don't.

(For even more granular weather data tracking in your area, view your 15-minute forecast in our Premium Pro experience.)

Is this a trend?: The answer appears to be "probably yes."

One recent study of 35 years of tropical cyclones around the world found an increased chance of rapid intensification from 1982 through 2017. One of the authors of the study, James Kossin, said in an American Meteorological Society talk the chance of rapid intensification increased by a factor of 5 in that period.

A separate 2023 study found Atlantic Basin hurricanes are twice as likely to rapidly intensify as they were 30 years ago.

And increasing ocean heat may be raising the chance of this happening, according to a 2021 study.

Ocean warmth was either at record or near-record levels in the Atlantic Basin's main development region for hurricanes, as well as the Gulf of Mexico in 2024.

Why it's important: If the chances of rapid intensification are increasing, that also increases the chance of stronger hurricanes, some of which could landfall at those higher intensities.

Furthermore, rapid intensification is a difficult challenge for forecasters, especially when it happens near land.

October 2023's Hurricane Otis was the poster child of this. Instead of its forecast Category 1 landfall, it unexpectedly mushroomed into a Category 5 hurricane before devastating Acapulco, Mexico, the country's costliest tropical cyclone on record.

MORE ON WEATHER.COM

- What November In Hurricane Season Usually Looks Like

- How Often Have Five US Landfalling Hurricanes Happened In One Season?

- 2024's Cat. 5 Hurricanes

Jonathan Erdman is a senior meteorologist at weather.com and has been covering national and international weather since 1996. Extreme and bizarre weather are his favorite topics. Reach out to him on X (formerly Twitter), Threads, Facebook and Bluesky.