Residents in the Leeward Islands, the United States (US) and British Virgin Islands were warned today to monitor the progress of a weather system that could develop into a fifth tropical storm in the Caribbean "any time over the next couple days", according to a report on www.cananews.net.

The Miami-based National Hurricane Centre (NHC) said that the system, located about 275 miles east of the Leeward Islands, continues to produce showers and thunderstorms and winds to gale force.

NHC said that the system could become a tropical depression or tropical storm "at any time over the next couple of days as it moves west-northwestward at about 10 miles per hour (mph)"

"There is a high chance greater than 50 per cent of tropical cyclone formation in this area during the next 48 hours. Interests in the Leeward Islands, the US and British Virgin Islands and Puerto Rico should monitor the progress of this system."

So far, there have been four named storms this hurricane season that began on June 1. However, only one of them, Bill, became a hurricane.

While it did not make direct landfall in the Caribbean, Hurricane Bill kicked up high surf and caused power outages in Bermuda.

The next system to reach tropical storm intensity with winds of at least 39 miles per hour will be called Erika.

Meanwhile, a tropical wave over the far eastern Atlantic Ocean between the Cape Verde Islands and Africa is showing some signs of organisation, but NHC said that there is a low chance of it becoming a tropical cyclone during the next 48 hours.