CNN
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Florida is bracing for what could be the strongest hurricane of the season in the United States. A patch of thunderstorms is strengthening in the Caribbean, potentially causing life-threatening storm surges and hurricane-force winds in the Southeast later this week.

The system will strengthen and is expected to rapidly strengthen into Hurricane Helene as it approaches the coast. The hurricane will then continue to move southeast, producing wind, rain and storm surge before it is expected to make landfall in Florida, according to the National Hurricane Center, which has designated the hurricane Potential Tropical Cyclone Nine.

A hurricane warning is in effect for Florida’s Gulf Coast from Englewood to Indian Pass, including Tampa Bay and Charlotte Harbor, the hurricane center said in a 5 a.m. update. A tropical storm warning is in effect north and south of the hurricane warning area, from Indian Pass to the Walton-Bay County line and from north of Bonita Beach to Englewood.

A tropical storm warning was also issued for Dry Tortugas in Florida and part of the Keys on Monday afternoon, and for Bonita Beach to Flamingo on Monday evening.

Florida Governor Ron DeSantis has declared a state of emergency for 41 of the state’s 67 counties to accelerate preparations and coordination between state and local governments in anticipation of the storm.

With little time to prepare, Tampa General Hospital began erecting a 10-foot flood barrier around the hospital Monday due to the potential for storm surge and shifts in the storm’s path.

On Monday, the potential cyclone was a mass of showers and thunderstorms raging in the far western Caribbean. The hurricane center predicts the system will intensify rapidly, likely becoming a hurricane by Wednesday evening and eventually reaching Category 3 strength.

The last storm to make landfall in the US as a Category 3 hurricane – Idalia – also made landfall in Florida, packing 125 mph (200 km/h) winds and a record-breaking storm surge from Tampa to Big Bend last August.

Idalia experienced a period of rapid intensification over the warm waters of the Gulf of Mexico, with sustained winds increasing to 55 mph (88 km/h) over the course of 24 hours.

The National Hurricane Center predicts the hurricane will make landfall in Florida’s Big Bend region, but CNN meteorologist Mary Gilbert says everyone from Florida’s Gulf Coast to eastern Louisiana should be on alert this week.

Strong, potentially damaging winds and storm surges are likely near the system’s eventual landfall. The system will also stir up Gulf seas and could produce rough waves and dangerous rip currents across much of the basin, especially later this week.

“The hurricane is expected to strengthen over the next few days and the system is expected to become a hurricane on Wednesday and further strengthen on Thursday as it moves across the eastern Gulf of Mexico,” the hurricane center said in a warning at 11 p.m. Monday.

Confidence in the exact path of the system increases after it forms, as predictive models struggle to accurately determine where the system is going without a center to aim for.

This stormy weather will potentially bring flooding and rainfall to parts of Central America, Mexico, Cuba and Jamaica as it attempts to organize into a tropical system. Hurricane and tropical storm warnings are already in effect for parts of Mexico and Cuba.

“Potential Tropical Cyclone Nine will bring heavy rainfall to portions of the western Caribbean, causing significant flooding and mudslides in western Cuba,” the National Hurricane Center said.

In its forecast issued at 5 p.m. ET on Monday, the hurricane center warned that the system’s expansion over the record-warm Gulf of Mexico would have far-reaching implications for the U.S.

“Storm surge, wind, and rainfall impacts will extend well from the center, particularly to the east of the system. Additionally, the rapid forward speed as it approaches the coast will likely result in further inland penetration of gusty winds across portions of the southeastern United States following landfall,” the report said.

Heavy rain is possible for much of the Southeast beginning around midweek. A Level 2 of 4 risk of flooding rain is in effect for much of Florida, Georgia, Alabama and parts of the Carolinas Thursday, according to the Weather Prediction Center.

Helene could also bring strong winds and torrential rain to much of Georgia and the Carolinas by Friday, potentially causing dangerous flooding and significant power outages.

“Heavy rainfall will likely result in locally significant flash and urban flooding across portions of Florida, with isolated flash and urban flooding possible across the Southeast, southern Appalachians, and Tennessee Valley Wednesday through Friday. Minor to isolated moderate river flooding will be possible,” the National Hurricane Center said.

Helene would be the fourth hurricane to make landfall in the U.S. this year and the fifth hurricane to hit Florida since 2022.

The repeated setbacks have pushed Florida’s insurance market to the brink, with insurers pulling out of the state due to the increasing risk of extreme weather events caused by climate change.