The system is threatening the densely populated Tampa metro area — which has a population of more than 3.3 million people — with a potential direct hit and menacing the same stretch of coastline that was battered by Helene.
Traffic was thick on Interstate 75 heading north Monday as evacuees fled in advance of Hurricane Milton. Crews are also hurrying to clear debris left by Helene.
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According to the National Hurricane Center's Live Hurricane Tracker, Milton will make landfall on the west coast of Florida late Wednesday. It's expected to be a Category 3 storm, which have winds of 111-129 mph (180-210 kph), when it hits the shore in the Tampa Bay region, which has not endured a head-on hit by a major hurricane in more than a century.
It could retain hurricane strength as it churns across central Florida toward the Atlantic Ocean. That track would largely spare other states ravaged by Helene, which killed at least 230 people on its path from Florida to the Carolinas.
Milton intensified quickly over the eastern Gulf of Mexico. Florida Gov. Ron DeSantis told reporters Monday afternoon the hurricane was far stronger than what was predicted two days ago.
Milton was a Category 5 hurricane with maximum sustained winds of 180 mph (285 kph) and was centered about 675 miles (1,085 kilometers) southwest of Tampa at late Monday afternoon.
Those winds eased to 155 mph (250 kph) by early Tuesday and the hurricane was downgraded to Category 4 status. It was centered about 560 miles (900 kilometers) southwest of Tampa. The hurricane center said Milton still posed "an extremely serious threat to Florida."
The entire Gulf Coast of Florida is especially vulnerable to storm surge.
Hurricane Helene came ashore some 150 miles (240 kilometers) away from Tampa in the Florida Panhandle and still managed to cause drowning deaths in the Tampa area due to surges of around 5 to 8 feet (1.5 to 2.5 meters) above normal tide levels.
Forecasters warned of a possible 8- to 12-foot storm surge (2.4 to 3.6 meters) in Tampa Bay. That's the highest ever predicted for the location and nearly double the levels reached two weeks ago during Helene, said hurricane center spokeswoman Maria Torres.
The storm could also bring widespread flooding. Five to 10 inches (13 to 25 centimeters) of rain was forecast for mainland Florida and the Keys, with as much as 15 inches (38 centimeters) expected in some places.
Tampa International Airport said it planned to stop flights at 9 a.m. Tuesday. The airport posted on X that it is not a shelter for people or their cars.
St. Pete-Clearwater International Airport said it is in a mandatory evacuation zone and will close after the last flight leaves Tuesday.
Mexican officials were organizing buses to evacuate people from the low-lying coastal city of Progreso on the Yucatan Peninsula after Mexico's National Meteorological Service said Hurricane Milton "may hit between Celestun and Progreso."
Celestun, on the western corner of the peninsula, is a low-lying nature reserve home to tens of thousands of flamingos. Progreso, to the east, is a shipping and cruise ship port with a population of about 40,000.