People in Jamaica were preparing as Hurricane Melissa strengthened on Sunday into a major Category 4 hurricane, threatening catastrophic flooding in the northern Caribbean.

The U.S. National Hurricane Center warns it could intensify to a Category 5 by Sunday night.

Melissa is expected to reach Jamaica's southern coast late Monday or Tuesday morning.

Authorities in Jamaica have activated shelters and closed Kingston's Norman Manley International Airport.

Melissa is the 13th named storm of the Atlantic hurricane season.

Melissa was centered about 110 miles (180 kilometers) south-southeast of Kingston, Jamaica, and about 280 miles (445 kilometers) south-southwest of Guantanamo, Cuba, on Sunday morning.

It had maximum sustained winds of 140 mph (220 kph) and was moving west at 3 mph (5 kph), the hurricane center said.

Melissa was expected to drop torrential rains of up to 30 inches (760 millimeters) in Jamaica and southern Hispaniola — Haiti and the Dominican Republic — according to the hurricane center.

Some areas may see as much as 40 inches (1,010 millimeters) of rain.

It also warned that extensive damage to infrastructure, power and communication outages, and the isolation of communities in Jamaica were to be expected.

Residents went out to buy groceries and supplies, and many found markets with few items.

“Trying to get last-minute things for the home, particularly I was looking to get some bread, but the shelves are empty," said Marc Edouard.

Melissa should be near or over Cuba by late Tuesday, where it could bring up to 12 inches (300 millimeters) of rain, before moving toward the Bahamas later Wednesday.

“There is nowhere that will escape the wrath of this hurricane,” Jamaican authorities said, adding that all members of the National Response Team are now on full alert.

AP video by Matias Delacroix and Kirk Wright