Tropical Depression Nineteen has formed in the Caribbean Sea and is forecast to continue strengthening, according to the National Hurricane Center.

Tropical Storm Sara formed in the Caribbean on Thursday ... during the middle portion of next week," the hurricane center said Thursday. "Residents in these areas should regularly monitor updates to the forecast."

A somewhat rare November storm system is gathering steam in the Caribbean Sea. Tropical Storm Sara will eventually make a turn to the east and Florida. Lots of factors in play but Tropical Storm Sara is expected to form this week and could become a major hurricane threatening the US next week.