Tropical Storm Isaac heads to Florida
Strong winds and heavy rain have arrived in southern Florida ahead of the expected arrival of Tropical Storm Isaac on Tuesday or Wednesday.
Authorities in Louisiana, Mississippi and Alabama have followed Florida in declaring states of emergency, and hundreds of flights have been cancelled and oil and gas production have been affected.
The storm has already claimed the lives of six people in Haiti, and in the US the Republican Party has delayed the start of its convention by a day.
Steve Kingstone reports from Tampa.