Isaias strengthens into a dangerous Category 3 hurricane on track toward the US Gulf Coast

BAYOU LA BATRE, Ala. (AP) — Isaias strengthened Friday into a major hurricane as it headed toward the U.S. Gulf Coast, where final preparations were being made for potentially life-threatening storm surges and high winds.

The hurricane is forecast to make landfall late Friday somewhere along the Alabama-Florida line and create dangerous conditions in the Florida Panhandle, southern Alabama and southern Mississippi, the National Hurricane Center said.

The Category 3 storm was packing 120 mph (193 kph) winds, and was expected to continue strengthening. Category 3 storms, considered major hurricanes, are capable of causing devastating damage, the center said.

Rain began falling along the coast Friday morning, and tropical storm conditions were expected to begin early in the afternoon.

Isaias was expected to weaken quickly as it hits shore and be downgraded to a tropical storm by Saturday afternoon as it moves north and inland along the Alabama-Mississippi line, the center said.

“Preparations should be rushed to completion as the weather will go downhill quickly today,” the hurricane center said in an early morning forecast. “While the storm is not expected to make landfall at peak intensity, it is likely that Isaias will still be a significant hurricane when it reaches the coast.”

Isaias, the first hurricane of the Atlantic season, was centered about 200 miles (322 kilometers) south-southeast of the mouth of the Mississippi River and moving to the north at about 15 mph (24 kph), the center said.

It was expected to make landfall between Mobile Bay on the Alabama coast and Choctawhatchee Bay in the Florida Panhandle in the evening.

Besides wind and storm surges, the hurricane will likely bring flash flooding and spawn tornadoes, the hurricane center said.

A hurricane warning was in place from Ocean Springs, Mississippi, to the western Florida Panhandle. Tropical storm warnings were issued from southeastern Louisiana to Aucilla River along Florida's Big Bend.

Preparations have been going on for days. On Thursday, residents boarded up windows and stacked sandbags while thousands of National Guard soldiers were deployed.

Isaias is expected to bring a storm surge as high as 5 to 7 feet (1.5 to 2 meters), with the deepest water hitting immediate coastal areas, along with large and dangerous waves, the hurricane center said.

Coastal communities moved quickly to prepare Thursday, as Alabama Gov. Kay Ivey ordered non-residents to immediately evacuate Gulf Shores, Orange Beach and Dauphin Island. Videos on social media showed traffic at a standstill on a highway leading out of Gulf Shores, where double-red beach flags signaled water access was closed.

Several counties announced mandatory evacuations for some coastal areas. The governors of Florida and Alabama declared states of emergency for dozens of counties, with Florida’s Ron DeSantis saying about 5,000 National Guard troops were expected to mobilize by Friday.

On Dauphin Island, a 15-mile (24-kilometer) barrier island off the Alabama coast, officials encouraged voluntary evacuations, particularly on its popular western section, which is vulnerable to storm surge.

Mayor Jeff Collier said he did not anticipate substantial damage, “but at the same time, these things are very fickle and a little jog here or there, or some last-minute increase in strength — we just have to be prepared for the worst.”

Meanwhile in the Pacific Ocean, Hurricane Simon, which formed as a tropical storm on Wednesday off of Mexico and became a hurricane late Thursday, was forecast to strengthen into a Category 4 hurricane.

Rico reported from Atlanta and Collins reported from Hartford, Connecticut. Also contributing were Associated Press reporters Kim Chandler in Montgomery, Alabama; Hallie Golden in Seattle; Kathy McCormack in Concord, New Hampshire; John Raby in Charleston, West Virginia; Laura Turbay in Little Rock, Arkansas; and Julie Walker in New York.

Mike Howard, foreground, and Joshua Brown board up Perdido Key Sports Bar as Hurricane Isaias approaches Perdido Key, Fla., Thursday, Oct. 8, 2026. (AP Photo/Gerald Herbert)

People walk on the beach at sunset as Hurricane Isaias approaches Pensacola Beach, Fla., Thursday, Oct. 8, 2026. (AP Photo/Gerald Herbert)

Daniel and Brand Harp, of Lebanon Tenn., here on vacation, pack their belongings to evacuate in the morning as Hurricane Isaias approaches Pensacola Beach, Fla., Thursday, Oct. 8, 2026. (AP Photo/Gerald Herbert)

This satellite image from the National Oceanic and Atmospheric Administration shows Hurricane Isaias in the Gulf of Mexico, Friday, Oct. 9, 2026. (National Oceanic and Atmospheric Administration via AP)

Larry Smith boards up his home with plywood ahead of Hurricane Isaias' expected landfall along the Gulf Coast in Dauphin Island, Alabama, Thursday, Oct. 8, 2026. (AP Photo/Octavio Jones)

A supersized El Niño’s decapitating winds and the Gulf of Mexico’s toasty, storm-fueling waters are battling over the future strength of Hurricane Isaias. And the storm’s tilt and eye show who’s winning.

For now, it's the waters charged by climate change.

All Atlantic hurricane season there has been “this battle between shear and just the overall conducive conditions,” said Colorado State University hurricane researcher Phil Klotzbach.

El Niño — the natural temporary warming of parts of the Pacific that warps weather worldwide — dominated. Its wind patterns smothered almost any wisp of a storm from strengthening in the Atlantic, while boosting what will soon be record high levels in the Pacific, Klotzbach said.

It's called wind shear and it pushes the tops and middle of storms around, making them lopsided and keeping them from making a complete circular eyewall, which is when storms can really power up, Klotzbach and University at Albany's Kristen Corbosiero said.

The other ingredients for a storm to turbocharge a storm are pushing back. There is plenty of fuel in warm water and moisture. The Gulf of Mexico is about 2.7 degrees Fahrenheit (1.5 degrees Celsius) warmer than normal. The 86 degree waters (30 degrees Celsius) are 100 to 500 times more likely to be that extra hot because of climate change from the burning of coal, oil and gas, said climate scientist Kristina Dahl, vice president of the nonprofit Climate Central, which calculates the boost global warming causes to extreme weather.

“But there’s a certain point where it’s like, I don’t care how hot the waters are and how much moisture you have, if shear gets to a certain point, the shear is gonna win,” Klotzbach said.

The thunderstorm seeds of something bigger earlier in the week grew from circular winds over Central America but often were lopsided and couldn’t quite form a crucial eyewall, all because of El Niño’s high-level strong winds that pushed a would-be storm's top sideways, experts said.

Then a window of moderation opened for just a couple of days, but it was enough, Corbosiero said. It makes sense it was in the Gulf of Mexico and in October, because El Niño has less of an effect in the Gulf than it does in the main Atlantic, she said. And storms often pop up in that region in October because of more northerly storm systems that help foster the right conditions.

Wind shear wasn’t exactly low, but it was a moderate level, when other factors like unusually warm waters and heavy moisture can kick in. Isaias rapidly intensified from 40 mph to 80 mph (64 kph to 129 kph) in a day and by late Wednesday, Isaias became the latest-in-the-season first Atlantic hurricane to form since 1914, Klotzbach said.

“The warm waters and high moisture won,” Klotzbach said. Isaias Friday was not tilting and had a strong eye, the hurricane center said.

By Friday morning, Isaias blew past the threshold for becoming a major hurricane with winds of 111 mph (178 kph), strengthening to 120 mph winds (195 kph). The National Hurricane Center forecasts it to weaken to a strong Category 2 storm before landfall.

Before Isaias comes ashore — forecast for probably somewhere from the Mississippi and Alabama coast to the Florida Panhandle late Friday night or early Saturday — the wind shear will strengthen from moderate levels of around 20 mph (32 kph) to 52 mph (84 kph) and then Isaias will start to struggle, which is good news for coastal residents, Klotzbach said.

But as of Friday morning, hurricane center forecasters said the coast is in “a tenuous spot” because it would only take a six-hour delay in the onset of that more intense wind shear for Isaias to bring a stronger-than-expected landfall. Regardless of what will happen with wind shear, it will still be a dangerous hurricane when it hits land, forecasters said.

“Once it gets to the coast, we know that the storm surge is going to be deeper and farther reaching because of sea level rise caused by climate change,” Dahl said. “So in this part of the world, there’s been about six and a half inches of sea level rise over the past 100 years or so that’s attributable directly to climate change.”

The National Hurricane Center is calling the surge “life-threatening.”

A warmer atmosphere means storms hold and then dump more rain, worsening flooding, Dahl said. The hurricane center is warning about urban, river and flash flooding in the Southeast this weekend.

“There’s a little bit of a battle here going on, but I think the really important thing to remember is that climate change is like this long-term big kahuna warming everywhere, and El Niño’s like a little icing on the cake,” Dahl said.

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Residents fill up their gas tanks and generators at the Costco Wholesale Gas Station ahead of Hurricane Isaias' expected landfall along the Gulf Coast, Thursday, Oct. 8, 2026, in Mobile, Ala. (AP Photo/Octavio Jones)

Residents pick up sandbags for storm preparation at the James Seals Jr. Parks & Recreation Center ahead of Hurricane Isaias' expected landfall along the Gulf Coast, Thursday, Oct. 8, 2026, in Mobile, Ala. (AP Photo/Octavio Jones)

Boat owner Tony Rice, right, and his friend Lance Connor haul doors onto his boat to secure it as Hurricane Isaias approaches Bayou La Batre, Ala., Thursday, Oct. 8, 2026. (AP Photo/Gerald Herbert)

This satellite image from the National Oceanic and Atmospheric Administration shows Hurricane Isaias surging toward the U.S. Gulf Coast on Thursday, Oct. 8, 2026. (National Oceanic and Atmospheric Administration via AP)