Hurricane Irma now category 4 with winds up to 130mph (209km/h) moved away from the Florida Keys and should make landfall on the west coast within hours.
High winds and storm surges are affecting the Miami area. More than 1 million homes are without power.All residents had been ordered to leave. Some surges could reach 15ft (4.6m).
Cities such as Tampa and St Petersburg lie in the path of the storm. The Tampa Bay area, with a population of about three million, has not been hit by a major hurricane since 1921.