Caribbean tropical storm upgraded to hurricane" alt="" width="299" height="199" align="right" class="newsArticleImage">

Image via Shutterstock

Tropical storm Gonzalo was upgraded to hurricane force overnight with warnings of high winds, heavy rain and flash floods across much of the Caribbean.

Puerto Rico and the US Virgin Islands and were among the areas expected to be affected yesterday.

The Foreign and Commonwealth Office issued upgraded travel advisories to cover many islands, including Antigua and Barbuda, Barbados, Jamaica, Grenada, St Lucia, St Vincent and the Grenadines, Dominican Republic and St Kitts and Nevis.

Gonzalo is forecast to continue gaining strength and become a major hurricane on Wednesday with sustained winds of 115 mph.

Most forecasts showed Gonzalo posing no threat of landfall in the mainland US and spinning away in a northerly direction over the Atlantic after passing Puerto Rico and the Virgin Islands.

People in Puerto Rico stocked up on water, batteries and other emergency supplies as government officials urged residents to take precautions against a possible strike by Gonzalo, which was forecast to pass to the northeast of the island.

Emergency services were placed on alert and storm shelters were being set up at schools and other facilities.

Royal Caribbean International’s Explorer of the Seas changed schedule to arrive early and spend the night in port.

Gonzalo is the sixth hurricane of the 2014 Atlantic hurricane season. In August, forecasters downgraded their outlook for the season, predicting below-normal activity with seven to 12 named storms and no more than two reaching major hurricane status, Reuters reported.

The FCO called on travellers in the Caribbean to monitor local radio and TV stations for updated weather reports and follow the advice of loca