Waters off MS Coast feel like a bathtub. What does that mean for future Hurricane Helene?

The heat has forecasters in awe.

The Gulf of Mexico bakes each summer, and the sun always beats down on the shallow shores of the Mississippi Sound.

But this year, scientists say the water is sweltering.

That’s bad news, they warned as a storm churned toward the Gulf of Mexico this week, where forecasters say it will draw strength from an ocean that is red as a flame on most maps of its temperature.

“It’s very concerning,” Diana Bernstein, an assistant professor at the University of South Mississippi’s School of Ocean Science and Engineering, said this summer. The heat, she said, is “like bringing more fuel to a fire.”

Warm water is worrying forecasters across the Gulf of Mexico and Caribbean Sea, where a path of warmth earlier this summer fueled Hurricane Beryl’s rise to becoming the earliest Atlantic Category 5 storm ever.

This week, forecasters say the heat could lead to similar danger: A storm forming in the Caribbean Sea is expected to strengthen rapidly over a hot ocean and make landfall in Florida as Hurricane Helene.

South Mississippi was outside the storm’s predicted track on Monday. But the Mississippi Sound’s temperatures mirror the Gulf: A National Oceanic and Atmospheric Administration temperature gauge at the Bay Waveland Yacht Club measured 88-degree water on Monday afternoon. In Pascagoula, at the NOAA Lab, the water was 85 degrees.

The numbers are higher than usual.

This week, ocean heat is “extremely” high, especially inside the Gulf of Mexico’s Loop Current, where forecasters predict future Hurricane Helene will soon pass, Brian McNoldy, a researcher at the University of Miami, wrote on social media.

He said water temperatures have reached record highs in both the Gulf of Mexico and Caribbean Sea, where the system was forming on Monday.

How hot oceans fuel hurricanes

McNoldy tracks the heat in a series of graphs, and the lines are all moving up.

Ocean warming is caused by climate change: scientists say seas absorb the world’s heat like a sponge. The temperatures have mostly shocked scientists in an area of the Caribbean and Atlantic where hurricanes often develop, but temperatures have also been above normal since early May in the Gulf.

Forecasters credited Beryl’s development this summer to record-hot ocean heat. The warmth helped Beryl become a Category 5 storm more than two weeks earlier than any other Atlantic storm of that category on record, according to Philip Klotzbach, a meteorologist who studies hurricane forecasts at Colorado State University.

Future hurricane Helene could strengthen the same way. Forecasters said Monday the storm would likely strike as a Category 2 or 3. It had not yet entered the Gulf of Mexico on Monday afternoon, and to reach hurricane status it will strengthen rapidly before its predicted landfall on Thursday, forecasters said.

Warm water adds moisture and energy to hurricanes, Megan Williams, a forecaster at the National Weather Service New Orleans, said this summer. The heat from the ocean gets transferred into the storm, she said, helping it grow stronger and faster.

That creates a dangerous event called rapid intensification, when hurricanes approaching the shallow, often warmer waters near land, grow stronger as they barrel rapidly toward a coast.

And as Beryl churned over a stretch of the Caribbean Sea where temperatures are far hotter than they were 24 years ago, it jumped quickly from a tropical storm to a Category 1 hurricane. The next day it was a Category 4.

And just two days after it became a tropical storm, Beryl pounded the Caribbean island of Carriacou and moved west as a Category 5.

Forecasters say any hurricane approaching a warm coastline could gain a last-minute surge in power.

The concern is not new — the ocean was the warmest it has ever been last year — but the hot Gulf and Caribbean has gained new focus this hurricane season, in part because of Beryl’s fast, early and dangerous force.

This week, the trend continued. On Sunday, McNoldy wrote, the Loop Current temperatures were “obliterating previous values for the date.”

This story was originally published July 3, 2024 at 5:00 AM.