A tropical storm swirling in the eastern Caribbean has raised the possibility that this year's Republican National Convention could be more dramatic than usual.
Tropical Storm Isaac was east of Guadeloupe, and some forecasters said it could become a hurricane on track to hit Florida next week, when Republicans gather in Tampa.
The US National Hurricane Centre's five-day forecast shows the storm blowing over the Dominican Republic, Haiti and Cuba but does not extend to Monday, when the four-day convention kicks off.
"It is too early to determine what, if any, impacts might be experienced in the Tampa area next week," said Dennis Feltgen of the US National Weather Service. "The US is not yet in the forecast track cone, and there is a great deal of uncertainty beyond that five-day time frame."
Thousands of party luminaries, officials and supporters will convene in Tampa to formally nominate Mitt Romney to challenge President Barack Obama in the November 6 election.