Tropical storm warnings were issued early Friday for much of the Florida peninsula, Cuba and the Bahamas as a system that battered Mexico moves through the Gulf of Mexico, bringing threats of heavy rain and wind for the weekend.

The U.S. National Hurricane Center in Miami said the storm once known as Agatha in the Pacific Ocean will be known as Alex in the Atlantic Ocean basin.

An advisory posted early Friday noted that data from a hurricane hunter aircraft indicate the system's maximum sustained winds had increased overnight and it was expected to develop "a well-defined center and become a tropical storm" as it approaches Florida, the hurricane center said. A system becomes a tropical storm when winds reach 39 mph (62 kph).

At 11:00 a.m. local time, the system was located about 430 miles (675 kilometers) southwest of Fort Myers and was moving northeast at 5 mph (8 kph).

Some strengthening is possible as the system approaches Florida on Friday afternoon and evening, the advisory said.

The U.S. National Hurricane Center predicts that rainfall up to 10 inches (25 centimeters) is possible in South Florida, including the Florida Keys. The storm is not expected to produce huge winds or major storm surge. But local flooding is likely and winds could be somewhat strong.

"Heavy rains will begin to affect South Florida and the Keys Friday and continue through Saturday," the Hurricane Center said in an online post. Also predicted is storm surge and flooding, the severity of which depends on the timing of tides.

Florida Gov. Ron DeSantis said the forecast was somewhat unusual in that substantial rains were expected in southwestern Florida on Friday and windy but drier conditions on Saturday. "The rain is actually beating the wind" instead of the two coming together, he said.