Hurricane Melissa, already a major category 4 storm, gathered steam Sunday as it took aim at Jamaica and other parts of the Caribbean, with forecasters predicting catastrophic flooding and urging residents to seek shelter immediately.

Jamaica faces damaging winds and heavy rainfall Sunday and Monday that could trigger catastrophic and life-threatening flash floods and landslides.

According to the hurricane center, Hurricane Melissa has a significant possibility of making landfall on Jamaica as a major hurricane and could maintain major hurricane strength when it reaches eastern Cuba. Forecasters say Melissa poses little to no risk for Florida and the U.S. at this time.

The National Hurricane Center's 11 p.m. Friday update reported that Tropical Storm Melissa is in the Caribbean Sea, 180 miles southeast of Kingston Jamaica and 245 miles southwest of Port Au Prince Haiti. Packing maximum sustained winds of 65 mph, it is tracking northwest at 3 mph.