(Bloomberg) -- Florida has declared a state of emergency for southern parts of the state as record downpours disrupted flights at major airports in Miami and Fort Lauderdale and prompted the partial closing of the I-95 freeway.

Governor Ron DeSantis declared the emergency in counties including Miami-Dade, Broward, Collier, Lee and Sarasota, citing forecasts of additional heavy rain and thunderstorms over the coming days that would exacerbate ongoing flood conditions. 

On Wednesday afternoon, more than 50% of the flights in and out of Fort-Lauderdale-Hollywood International Airport were either delayed or canceled, with similar figures for Miami International Airport, according to Flight Aware. The Florida Highway Patrol shut down a portion of Interstate 95 in Broward County due to flooding caused by the heavy rainfall, according to an agency post on the social-media platform X. 

Already, several daily rainfall records were set on Tuesday, including 6.47 inches (16 centimeters) in the Sarasota-Bradenton area and 3.3 inches in Fort Lauderdale, the National Weather Service said. Miami International Airport got 3.59 inches, just shy of the all-time high for that date. 

The deluge will continue through the weekend as the showers slowly shift southward, said Peter Mullinax, a forecaster with the US Weather Prediction Center. As much as 6 more inches may fall through late Thursday,. with some areas getting as much as 9 inches, the National Weather Service said. 

“It is quite active down there,” Mullinax said by phone. “As the day unfolds there will be another resurgence of storms.”

The rains are coming from an elongated low-pressure system pinned to the area by high-pressure systems in the central US and the Caribbean that have allowed moisture to flow inland from the Gulf of Mexico. There is a 20% chance the showers will strengthen into the Atlantic’s first tropical storm, which would be named Alberto, in the next seven days, the National Hurricane Center said.

Storms early in the Atlantic hurricane season, which began June 1, often form close to the US coast from systems that moved across North America. These storms aren’t usually as powerful as later hurricanes and don’t really give a clue as to what the rest of the season will bring.

However, forecasters are expecting an active year. Colorado State University is predicting 23 named storms across the Atlantic, with 11 becoming hurricanes and five growing into major systems with winds of 111 miles (179 kilometers) per hour or more. On average, about 14 named storms form in the Atlantic during the season.

(Updates with state of emergency declaration)

©2024 Bloomberg L.P.