Rafael is forecast to strengthen Tuesday and will likely become a hurricane over the next 24 hours as it batters the western Caribbean on the first leg of an uncertain journey toward the US Gulf Coast.

Rafael is the 17th named storm of the Atlantic hurricane season, and it could become the 11th hurricane. The season lasts until Nov. 30.

The National Hurricane Center forecast Tropical Storm Rafael to grow into the season’s 11th hurricane on Tuesday as it moved toward Cuba with winds and