Hurricane Irma pounded the Bahamas before making landfall Friday night in the northern part of Cuba as it cycled toward Florida. It is expected to hit there late Saturday with wind speeds powerful enough to snap trees and power poles and tear the roofs off buildings. And Gov. Rick Scott said the lower half of Florida could face life threatening storm surge as early as Saturday morning.

The storm’s outer bands were hitting the Florida Keys on Saturday morning. The National Hurricane Center warned of “life-threatening surge and wind.”

Irma, which made landfall on the Camagüey Archipelago of Cuba as a Category 5 hurricane with 160-mile-per-hour winds, had already caused flooding in Cuba’s northeast on Friday as it continued to move along the nation’s northern coastline, according to the National Hurricane Center.

In the Caribbean, where more than 20 people were killed, residents in Barbuda and St. Martin, islands that suffered excessive damage from Irma, wearily prepared for Hurricane Jose, the Category 4 storm that could hit those islands within the next two days.

In Florida, officials estimated that 5.6 million residents had been ordered to evacuate. They repeatedly urged Floridians not to underestimate the power of Irma. Governor Scott has said it would be “way bigger than Andrew,” referring to the 1992 storm that was the most destructive hurricane to hit the state.

“If you have been ordered to evacuate, you need to leave now,” he said at a news conference Friday evening. “Not tonight, not in an hour, now.”

Brock Long, the FEMA administrator, cautioned that people from Alabama to North Carolina should be monitoring the storm and making preparations.

On Friday, Gov. Kay Ivey of Alabama issued a full state of emergency in an effort to better prepare the state for Irma. Gov. Henry McMaster of South Carolina also announced that he would order the mandatory evacuation of several islands — including the popular resort island Hilton Head — beginning at 10 a.m. Saturday.

Here’s the latest:

• The National Hurricane Center said Irma remained “extremely dangerous,” and the Florida Keys were at risk of “life-threatening inundation.” Check out our maps tracking the storm.

• At least 20 people have died because of the storm in the Caribbean.

• In Florida, a 57-year old man died on Thursday after he fell off a ladder while trying to install storm shutters at a house in Broward County, the Davie Police Department said on Friday.

• Another storm, Hurricane Katia, was downgraded to a tropical storm from Category 1 after making landfall north of Tecolutla on Mexico’s eastern coast.

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