Florida authorities went door-to-door warning residents of the massive hurricane, sending crowds jamming highways as they fled north wards.
The Category 4 storm had maximum sustained winds of 155 mph Saturday morning. Before it was slightly downgraded, it made landfall on Cuba's Camaguey Archipelago as a Category 5 hurricane, the National Hurricane Center said Friday night.
As the weather forecasts and warnings from officials grew increasingly dire, hundreds of thousands of people across Florida fled their homes before the rapidly closing window to escape Irma's wrath slammed shut. Forecasters said Irma, a hurricane of remarkable size and power that already has battered islands across the Caribbean, would approach South Florida by Sunday morning is likely to slam into its southern tip before tracking north across a heavily populated area.
"It's not a question of if Florida's going to be impacted, it's a question of how bad Florida's going to be impacted," William "Brock" Long, administrator of the Federal Emergency Management Agency, said Friday at a news conference.