Melissa, now a Category 5 storm, was expected to slam into the southern coast of Jamaica on Tuesday, Oct. 28, before approaching Cuba as a major hurricane and crossing the Bahamas, forecasters said. Melissa poses no threat to the United States.

Hurricane Melissa strengthened into a Category 5 storm Monday as it drew closer to Jamaica, where forecasters said it would unleash catastrophic flooding, landslides and widespread damage.

“Destructive winds, especially in the mountains, will begin by [Monday] evening, leading to extensive infrastructural damage, long-lasting power and communication outages and isolated communities,” N...