The National Hurricane Center said Hurricane Rafael grew into a major Category 3 storm Wednesday ahead of landfall in Cuba as it headed toward the Gulf of Mexico, while the Florida Keys remained under a tropical storm warning.

Rafael will make a landfall in Cuba as a major Category 3 hurricane, but it will weaken considerably as it moves into the Gulf of Mexico.

About 17% of crude oil production and 7% of natural gas output in the U.S. Gulf of Mexico was shut in response to Hurricane Rafael, the U.S. Bureau of Safety and Environmental Enforcement said on Wednesday.