Washington, Sep 10 (IANS): Violent winds and outer rain bands of Irma, which was now a Category 3 hurricane, lashed the Florida Keys on Saturday and could make a landfall as a Category 4 storm.

According to CNN, with sustained winds at 120 mph, Irma slowly began turning from Cuba's northern coast up into the Florida Strait on Saturday, the National Hurricane Center said.

The storm is expected to strengthen once it moves away from Cuba, turning north while remaining a powerful hurricane when it reaches Florida.

Irma's eye was due to strike the Florida Keys on Sunday morning before driving up the state's southwestern coast Sunday afternoon, according to the hurricane center.

Officials warned the 6.5 million residents under mandatory evacuation orders that time was running out.

"If you have been ordered to evacuate, you need to leave now. This is your last chance to make a good decision," Florida Governor Rick Scott was quoted as saying.

"You can't survive these storm surges. You've got to get out. You've got to evacuate. This storm is coming. Once the storm's here, we can't evacuate anybody," Scott said.

Federal Emergency Management Agency Administrator Brock Long said if people did not evacuate the Keys, they were on their own.

"The message has been clear: The Keys are going to be impacted. There is no safe area within the Keys. And you put your life in your own hands by not evacuating," he said.

The officials warned that the storm surge could reach as high as 15 feet in some areas.

A storm surge warning is in place for the Florida Keys, Tampa Bay and an extensive stretch of coastline wrapping most of the way around the state, the report said.