MIAMI — Read the latest with Saturday’s live updates on Hurricane Irma.

After plowing a path of destruction through the Caribbean and forcing hundreds of thousands to flee in one of the largest evacuations in American history, Hurricane Irma began to maul southern Florida on Saturday and was poised to howl up its west coast Sunday with deadly force and fury.

The storm’s eye was on track to hit the Lower Keys early Sunday, the National Hurricane Center said in its 5 a.m. Eastern advisory.

The time to gather supplies was over, and in most of the region, it was getting too late to run. The Florida Keys faced a potentially catastrophic brew of winds reaching 130 miles an hour and a storm surge that threatened to drown whole islands. By Saturday evening, the ocean around Key West was spilling into hotel parking lots and onto roads, while tornadoes rumbled like freight trains through Palm Beach and Broward Counties.

On the Gulf Coast, a late westward turn in the forecast had put Naples, Fort Myers and the heavily populated peninsulas of Tampa Bay directly in Irma’s track. Officials who had earlier expected a lighter blow from the storm spent the day frantically turning schools and other fortified buildings into shelters as fast as evacuees could wedge into them. Shelters opened. They filled. More opened. More filled. Long lines outside were bulging with suitcases, light furniture, pet carriers and jitters.