At last the eye of Hurricane Irma has hit Florida’s southern islands as a category four storm, forecasters say.
The storm is expected to pummel the low-lying Keys with winds reaching 130mph (209km/h), before travelling north-west up Florida’s Gulf Coast.
More than 6.3 million people were told to evacuate Florida, with warnings of a huge storm surge that would be “life-threatening” to anyone in its path.
Irma has already devastated parts of the Caribbean with at least 25 deaths.
Extreme winds, around the eye of the hurricane, are expected to last for the next two hours in the Lower Florida Keys area, which includes Key West.
All residents had been ordered to leave amid fears that a storm surge reaching 15ft (4.6m) could hit the coral cay islands, most of which are only a few feet above sea level.
One official had warned staying on the islands would be “almost like suicide”.
As the eye of the storm is expected to move north to mainland Florida, more than 430,000 homes in the state are reported to be without power and some 50,000 people have taken refuge in shelters.
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.
Florida’s Governor Rick Scott told NBC’s Today Show that though authorities had prepared all week for the arrival of Irma, the prospect of such a large storm surge was “really scary”.