A tropical disturbance building in the Caribbean Sea has been designated as Potential Tropical Cyclone 19 by the National Hurricane Center, and is forecast to strengthen into a tropical storm – known as Tropical Storm Sara – over the next few days.

"Not only does this have a significant chance of becoming a hurricane, but it may become a major hurricane very quickly," hurricane expert Alex DaSilva said

A tropical wave producing a cluster of showers and thunderstorms across the Caribbean has a 90% chance of becoming a tropical depression by the weekend.