( 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 . NASA scientist links climate change , extreme weather . Lightning strikes outside NASCAR race , kills 1 . Journalist Samantha Lugo and CNN 's Sarah Dillingham contributed to this report .
Tropical Storm Ernesto is expected to become a hurricane by Monday night . The storm will be the first Category 4 or higher on the Saffir-Simpson scale of hurricanes since Wilma in 2005. Nicaraguan officials say they are evacuating 1,500 people from coastal areas . Ernesto is expected to near the Honduran coast Monday night .