Florida is bracing itself for tropical storm Isaac after it killed as many as six people in Haiti and caused destruction in Cuba.
No casualties were reported in Cuba after Isaac hit only the east side of the island instead of snaking up its entire length, reported Reuters.
Isaac is currently 257 miles south east of Key West and moving at around 20mph.
Warnings have been issued in Florida Keys and a state of emergency declared. The storm is likely to hit Florida later on Sunday.
Louisiana and New Orleans have also been given warnings as Isaac approaches.
According to the National Hurricane Centre in Miami, the storm gathering speed and is likely to be a Category Two hurricane when it reaches Florida. Hurricanes are rated from one to five based on their intensity, and Isaac's rating means the Keys are likely to experience a hurricane with winds 96-110 mph and a storm surge of water generally 6-8 feet above normal.
A satellite picture of Isaac taken on Friday
Republican officials delayed the start of their convention in Tampa by one day, reiterating their concern for the safety of convention delegates. The delegates would have been bussed into downtown Tampa on Monday for a procedural vote call, reported HuffPost Politics. A concert has also been cancelled over flooding fears.
Thousands of people in Haiti remain at risk from flooding and disease despite the earthquake-ravaged nation avoiding the worst of tropical storm Isaac, according to British aid agencies.
Oxfam said initial assessments of the aftermath of the storm, which cleared the country's landmass yesterday, suggest the damage was not as great as feared.
Children in Haiti shelter in the aftermath of tropical storm Isaac
Charity workers are now battling to get emergency supplies to the worst hit areas of the nation, which was rocked by a massive earthquake that claimed the lives of more than 220,000 people two years ago.
Nearly 8,000 people were evacuated from their homes as 24 hours of steady rain caused widespread flooding and left makeshift camps built after the 2010 earthquake submerged by water.
The storm also laid waste to crops, knocked down telephone lines and wiped out power supplies in the worst hit areas.
According to Oxfam, camps in the capital Port-au-Prince, such as Jean Marie Vincent, were flooded, as well as towns in the south, including Les Cayes, Jacmel and Nippes.
Heavy rainfall is forecast in the wake of the storm, with up to 20 inches of rain predicted in Hispaniola.
The charity said that nearly 400,000 Haitians still living in refugee camps after the earthquake remained "highly vulnerable" to the threat of flooding, landslides and water borne diseases, especially cholera.
It said emergency teams are heading to the affected areas of the island to carry out in-depth assessments and provide clean water, hygiene kits and information about sanitation to those in need.
Jane Cocking, Oxfam's humanitarian director, said: "The storm may have passed but living conditions in Haiti remain so challenging for so much of the population that it's far too early to say the threat is over.
"People in Haiti have so little that they are incredibly vulnerable to the risks posed by flooding and disease. They remain in desperate need of our help."
The aid agency is in the process of contacting its supporters to ask for donations to help support its emergency work in Haiti, which is often cited as the poorest country in the western hemisphere with four in five of the population living on less than two US dollars a day.
In the shanty town of Cite Soleil, just north of Port-au-Prince, around 300 homes had either their roofs blown off or were sitting in three feet of water, according to Rachel Brumbaugh, operation manager for the US non-profit group World Vision.