Parts of Florida are now under a hurricane watch as the chance Tropical Storm Debby could be a hurricane when it makes landfall in the state increases. The storm, which is now Tropical Depression Four, is also forecast to slow down significantly after making landfall and wring out multiple days of rain in the Southeast, increasing the chances for significant flooding there.
The hurricane watch was issued for parts of Florida’s Big Bend region, where the National Hurricane Center forecasts a landfall as a strong tropical storm by Monday morning. The area is still recovering from a devastating blow by Category 3 Hurricane Idalia last August. Other alerts warning of tropical storm conditions over the next 48 hours span the entire western Florida coast south of the Big Bend and include Tampa, Sarasota, Fort Myers and Naples. Tropical Depression Four currently has maximum sustained winds of 30 mph and is about 170 miles southeast of Key West, just off the coast of Cuba, according to the National Hurricane Center’s 8 a.m. ET update.
The storm is expected to enter the eastern Gulf of Mexico on Saturday and officially become Tropical Storm Debby, according to the hurricane center. Tropical storm conditions could begin Saturday night in parts of southwest Florida, and rain will start impacting parts of South Florida. “Very Intense” rainfall is expected in Southwest Florida Saturday and a widespread 3 to 5 inches of rain could fall, according to the Weather Prediction Center. The intense rain will be potent enough to cause flash flooding, even in marshy areas of the state more capable of handling excess water.
The storm is forecast to continue to strengthen through the weekend and up to landfall while tracking through the Gulf of Mexico parallel to the western coast of Florida. Shifts in the storm’s exact track and strength are still possible over the next 48 hours, but a key factor in the increasing chances for a hurricane is how much time the system spends over record-warm water in the eastern Gulf of Mexico. Warm water is fuel for storms to strengthen and potentially rapidly intensify, a phenomenon becoming more likely as global temperatures rise because of fossil fuel pollution. Forecasters shifted the storm’s track to the west and believe the storm will spend more time over water now. “The westward shift to the track forecast now also keeps the system over the warm waters of the Gulf of Mexico longer, giving the system additional time to potentially strengthen,” the hurricane center said. “It is important to note that because of the forecast track being parallel to the west coast of Florida, the location and timing of a potential landfall cannot be pinned down at this time.”
Where and when the storm comes ashore and how strong it is at that time will affect the risk of “life-threatening” storm surge. Up to 5 feet of storm surge is possible in parts of the Big Bend and up to 4 feet is possible from Bonita Beach north through Tampa Bay. No matter its strength, torrential, flooding rain will be the most significant impact from the storm – especially with the system forecast to slow down after landfall.
After landfall Monday, the storm is forecast to track to the northeast over portions of northern Florida and southern Georgia. But the atmospheric components that help steer and push storms along are forecast to breakdown and cause future-Debby to slow significantly while over the Southeast early next week. The flood threat increases dramatically with slower storms as they linger over the same areas and dump repeated bouts of heavy rain. Five to 10 inches of rain – potentially more – is forecast over coastal portions of Georgia, South Carolina and North Carolina.
As a result, the risk of flooding rainfall was increased to a level 3 out of 4 over the coasts of Georgia and South Carolina, including Savannah and Charleston, for Monday into Tuesday. It’s also possible that this risk level will increase to a level 4 of 4 depending on the future track of the storm, the Weather Prediction Center said. Freshwater flooding – flooding caused by rainfall – has become the deadliest aspect of tropical systems in the last decade, according to research conducted by the National Hurricane Center. A world warming due to fossil fuel pollution is making this potential threat more dangerous. Studies also have shown tropical systems are slowing down over time, which means they’re more likely produce greater rainfall totals over a given area. Oceans are also getting warmer and supercharging storms, pumping them full of moisture. A 2022 study published in the journal Nature Communications found climate change increased hourly rainfall rates in tropical storms by 5 to 10% and in hurricanes by 8 to 11%.
Florida Gov. Ron DeSantis has declared a state of emergency for 54 of the state’s 67 counties to mobilize resources as the storm churned toward the Sunshine State. “Floridians are encouraged to monitor weather conditions, listen to all orders from local officials, create disaster preparedness plans, and stock disaster supply kits with food, water, and other necessities for their households,” the governor’s office said Friday. Sandbag distribution began Friday for residents in several communities in the Orlando and Tampa metros. Multiple counties in the state’s panhandle – including Escambia, Okaloosa and Santa Rosa – started distributing sandbags Thursday. “You still have some time to put your disaster supply kit together,” Hurricane Center Director Michael Brennan said Friday. “Make sure you have multiple days of food, water, prescription medicines. Keep your gas tank full, cash on hand, and keep batteries. Make sure your phone’s charged and make sure you have a battery powered radio.”