(CNN) -- The Mexican and Belizean governments issued hurricane warnings Monday for the east coast of the Yucatan Peninsula as Tropical Storm Ernesto churned toward the area.
The storm is expected to become a hurricane by Monday night.
In Nicaragua, government officials said they were evacuating about 1,500 people in coastal areas and had banned boats from setting sail.
As of Monday afternoon, the storm was about 160 miles (260 kilometers) east of Cabo Gracias a Dios on the Nicaraguan-Honduran border, the National Hurricane Center reported. Ernesto was moving west-nothwest at 12 mph with maximum sustained winds of 65 mph.
The storm was expected to pass to the south of the Cayman Islands and near the northern coast of Honduras on Monday night.
Belize also issued a hurricane warning for its east coast. Areas of the Cayman Islands, Honduras and the Yucatan Peninsula are under tropical storm warnings.
Meanwhile, Florence weakened to a post-tropical system.
No coastal watches or warnings were in effect for that storm, which was about 1,515 miles (2,440 kilometers) east of the northern Leeward Islands late Monday morning, the hurricane center said. It was moving west at about 15 mph.
Maximum sustained winds dipped to 35 mph, and further weakening is forecast in the coming days.
Journalist Samantha Lugo and CNN's Sarah Dillingham contributed to this report.