MIAMI (AP) - Newly named Tropical Storm Michael could strengthen to a hurricane as it heads to the Florida Panhandle, the U.S. National Hurricane Center said Sunday.
The hurricane center upgraded the tropical depression in the Caribbean to a named tropical storm, saying it had winds of up to 40 mph (65 kph).
The storm could strengthen into a hurricane by Tuesday night or Wednesday, the hurricane center said.
The hurricane center advised residents along the northeastern and central U.S. Gulf Coast to monitor the storm's progress.
Florida Gov. Rick Scott on Sunday said he planned to declare a state of emergency for counties in the Florida Panhandle and the Big Bend area of the state. The declaration would free up resources for storm preparation.
"As we continue to monitor this storm's northward path toward Florida, it is critically important that our communities have every available resource to keep everyone safe and prepared," Scott said in a statement.
The north Florida city of Tallahassee on Sunday opened two locations where residents could get sandbags in case of flooding.
"While the impacts are still uncertain, our area could experience increased wind activity and heavy rainfall, which could cause localized flooding and downed trees," Tallahassee officials said in a statement.
The city of Pensacola tweeted to residents, "be sure you have your emergency plan in place."
The storm was located by midday Sunday about 90 miles (145 kilometers) south of Cozumel, Mexico.
A tropical storm warning was in effect for the Cuban provinces of Pinar del Rio and the Isle of Youth as well as the coast of Mexico from Tulum to Cabo Catoche. A warning indicates tropical storm conditions are expected, in this case, within 24 hours.
An Air Force hurricane hunter airplane was being sent into the storm to investigate, the hurricane center said.
Michael is the 13th named storm of the 2018 hurricane season, according to hurricane center spokesman Dennis Feltgen.