A disturbance in the Caribbean strengthened into Tropical Storm Rafael on Monday afternoon. The storm is forecast to become a hurricane on Tuesday.
Rafael, previously known as Potential Tropical Cyclone 18, formed on Sunday. As of Monday at 4 p.m. ET, it was located about 175 miles south of Kingston, Jamaica, with maximum sustained winds of 45 mph, and moving north at around 9 mph, according to the National Hurricane Center.
Rafael is the 17th named storm of the Atlantic hurricane season, and will be the 11th hurricane if it strengthens further as expected. The season lasts until November 30, though peak activity is usually around September 10.
The storm system is expected to approach the United States later in the week, the NHC said, and a tropical storm watch was issued Monday afternoon for the Lower and Middle Florida Keys and for the Dry Tortugas. Parts of Florida and nearby areas of the Southeast could see heavy rainfall by mid to late week, though NHC forecasters said it is still too early to make predictions about impacts for the Gulf Coast.
A hurricane warning has been issued for the Cayman Islands, and a tropical storm warning is in effect for Jamaica.
The government of Cuba issued a hurricane watch for a handful of provinces, and a tropical storm watch for other areas.
Forecasters expect the weather system to move near Jamaica late on Monday, then to be near or over the Cayman Islands by late Tuesday, at which point it may be near or at hurricane intensity. It is then forecast to approach Cuba on Wednesday.
As early as Monday morning, NHC forecasters said the chance that the storm would become a hurricane was "near 100%" over the next 48 hours.
Rafael is forecast to dump 3 to 6 inches of rain across much the western Caribbean, and up to 9 inches in some areas. The heaviest precipitation is expected in Jamaica.
Minor coastal flooding is possible in Jamaica Monday evening, and storm surge up to 3 feet is expected in the Cayman Islands on Tuesday, the NHC said. Flooding and mudslides could also occur in parts of Jamaica and Cuba.