A tropical low pressure area over Cuba is becoming more organized on Saturday and is likely to bring heavy rain and coastal flooding to much of Florida’s Gulf Coast, weather experts said.

The storm weakened to a tropical depression late Friday and is forecast to strengthen into a tropical storm Saturday night when it reaches sustained winds of 39 mph or greater. If the depression reaches tropical storm status, it will be named Debby, the fourth named storm of the Atlantic hurricane season.

On Saturday morning, the circulation centered just south of Cienfuegos, Cuba, but associated winds and thunderstorms spread across a wide area, including southern Florida, the Florida Keys and the Bahamas. One location in the middle of the Florida Keys island chain reported sustained winds of 30 mph on Saturday morning.

The National Hurricane Center in Miami forecasts the low pressure area will strengthen as it curves north off the coast of southwest Florida, where the water is extremely warm and temperatures are approaching 90 degrees Fahrenheit (32 degrees Celsius) this week.

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Forecasts call for the system to make landfall as a strong tropical storm late Sunday or early Monday and cross northern Florida into the Atlantic Ocean. There, it is likely to remain a tropical storm threatening Georgia and the Carolinas early next week. Tropical storm warnings have been issued for much of Florida’s west coast and the Dry Tortugas. A hurricane warning has been issued for parts of the Big Bend, and Debby is considered likely to reach hurricane status before making landfall.

Flat Florida is prone to flooding even on sunny days when coastal areas are flooded by high tides called king tides. This storm is forecast to produce storm tides of 2 to 4 feet along much of Florida’s Gulf Coast, including Tampa Bay, with higher tides of 3 to 5 feet farther north in Florida’s sparsely populated Big Bend region, where the Florida peninsula curves westward toward the state’s Panhandle.

Tropical storms and hurricanes can also cause river flooding and overflow drainage systems and canals across the region. Forecasters are warning of 5 to 10 inches of rain, which could lead to “locally significant” flash and urban flooding. Forecasters are also warning of moderate flooding for some rivers along Florida’s West Coast.

The heaviest rainfall next week could be seen along an area of ​​the Atlantic coast from Jacksonville, Florida, north to Savannah, Georgia, and Charleston, South Carolina.

It was windy and stormy on Long Key Saturday morning, but Scott Battle, operator of Florida Boy Bar and Grill, said conditions were “good.”

“It sputters occasionally and blows a little bit, but it’s not too bad,” he said on the phone.

On Friday, people in some Florida cities filled sandbags to protect against possible flooding. Florida Gov. Ron DeSantis declared a state of emergency for most of Florida’s counties, from the Florida Keys to Central Florida and the Tampa Bay area and the western Panhandle.

Christina Lothrop is the general manager of the Blue Pelican Marina on Hernando Beach, a barrier island about 50 miles north of St. Petersburg. She said Saturday still looked like a normal summer day, with the public ramp across the street bustling with people launching boats and local bars and restaurants filling the water.

“Today it’s a little bit normal, and this is a little bit strange,” Lothrop told The Associated Press by phone.

Meanwhile, Lothrop said workers at his marina have been preparing for the storm since Tuesday, securing boats stored on shelves, putting away tackle boxes and tying down anything that could get blown around.

“What we’re doing now is mostly tying up boats,” he said, adding that boats would not be left in the water to prevent them from breaking loose and drifting away or causing damage.

Lothrop said he will be removing computers from the floor and sandbagging and taping the doors shut before the marina store closes Saturday. He said he mostly fears a storm surge. Last year’s Hurricane Idalia pushed about a foot of water into the store. Like many coastal communities in Florida, Hernando Beach is built around a series of man-made channels that provide easy access to the water but also act as a highway for storm surge.

For some Floridians, the name Debby brings back fond memories of the 2012 tropical storm of the same name, which caused $250 million in losses and eight deaths, seven of them in the Sunshine State. That storm dumped torrential rain from the Gulf Coast to northern Florida, including an astronomical 29 inches at one location south of Tallahassee.

Rick Falkenstein, owner of Hurricane Seafood Restaurant in St. Pete Beach, told WTSP-TV he remembers “high tides, flooding” from that storm.

Pinnellas County crews have halted a $5 million beach resurfacing project that was necessary due to erosion from past storms.