Tropical Storm Rafael formed Monday afternoon in the Caribbean Sea, where it is expected to cross Jamaica, the Grand Cayman Islands, and Cuba, before entering the Gulf of Mexico this week. It is forecast to strengthen into a hurricane before weakening back down to a tropical storm in the Gulf.

Tropical Storm Rafael is passing south of western Jamaica and is forecast to strengthen into a hurricane possibly by Tuesday evening.Rafael, which formed Sunday and was previously known as Potential Tropical Cyclone 18,

Tropical Storm Rafael gaining strength Tuesday morning after forming in the Caribbean Sea, with forecasters saying it will strengthen into a hurricane with predictions the storm is headed for the U.S.