FLORIDA — Hurricane Irma was expected to restrengthen after weakening late Saturday morning into a Category 3 storm, its strong winds and rain bands already lashing the Florida Keys as dire warnings predicted devastating gales and potentially deadly storm surge.

Packing sustained winds of 125 mph as it continued to batter Cuba, the storm was due to bring hurricane conditions by Saturday night to southern and central Florida, the National Hurricane Center said.

Irma’s eye was due to strike part of the Florida Keys early Sunday morning before driving up the state’s southwestern coast toward Tampa Bay by Sunday afternoon, according to the hurricane center. As much as 20 inches of rain was predicted through Wednesday across the Florida peninsula and southeast Georgia.

“(The core) is forecast right now to still go through the lower keys, not quite to Key West, and then on up to Naples, on up to Cape Coral, with a Category 4 wind of 140 mph,” CNN meteorologist Chad Myers said earlier Saturday morning.

After Saturday at noon, it would be too late for residents to leave specified evacuation zones in southwestern Florida, Gov. Rick Scott said hours earlier.

“The storm is here,” he said. “This is a deadly storm, and our state has never seen anything like it.”

Even as Irma aimed for Florida’s western coast, Florida’s eastern coastline remained in severe danger from storm-surge flooding, forecasters warned.

Florida authorities have gone door to door to warn residents about the dangerous storm, sending throngs onto jammed highways as they fled north. More than 5.6 million people have been ordered to evacuate, Scott said, and many coastal residents already have moved inland.

“If you have been ordered to evacuate, leave now — not tonight, not in an hour, now,” Scott said Friday night.

“This is as real as it gets,” tweeted the National Weather Service.

Irma hit Cuba’s Ciego de Avila province on the Camaguey Archipelago late Friday as a Category 5 hurricane. The storm’s violent gusts destroyed the instrument used to measure wind strength, Cuba’s meteorological agency reported. Waves as high as 23 feet were recorded, and bigger ones remained a possibility as Irma plodded west, officials said.

Even before hitting Cuba, Irma had proven catastrophic, killing 24 people this week in the Caribbean and leaving entire islands in ruins.

Here are the latest developments:

— Irma’s center was 175 miles southeast of Key West at 11 a.m. ET Saturday.

— Hurricane warnings were extended north along Florida’s west coast as far as Perry, and along the eastern coast to include Fernandina Beach, north of Jacksonville. A storm surge warning wraps around the state, from Brevard County to Tampa Bay.

— About 50,000 people are in 260 shelters statewide, Scott said, and 70 more shelters will open Saturday.

— As Irma pushes toward Florida, as many as 26 million people in the Dominican Republic, Haiti and Cuba could be exposed to destructive winds and torrential rain, the Red Cross said, with 1.2 million people already battered by the storm. Hurricane warnings were still in effect Saturday for parts of central Cuba.

— In the Bahamas, hurricane warnings remained in place early Saturday. Storm surge as high as 20 feet — well above the islands’ elevation — were possible, Myers said. About 390,000 live in the nation of islands.

— Of the 24 deaths blamed on Irma, nine were in unspecified French territories, one on Barbuda, one in the British overseas territory of Anguilla, two in Dutch-administered St. Maarten, four in the British Virgin Islands, four on the US Virgin Islands, and three in Puerto Rico.

— Irma brought heavy rain and powerful winds to the low-lying Turks and Caicos Islands. The capital island of Grand Turk suffered “quite a bit of damage,” including to part of a hospital’s roof, Gov. John Freeman told CNN.

Nervous Florida waits

US and European forecast models predicted Irma’s eye could strike the Florida Keys, then the Everglades, west of Miami, early Sunday morning.

“It’s not a question of whether Florida is going to be impacted — it’s a question of how bad Florida is going to be impacted,” Federal Emergency Management Agency Administrator Brock Long said.

Irma shifted slightly west overnight into Saturday, putting cities including Naples and Tampa in the direct path of the storm’s eye.

And though the hurricane’s core has the most power, Irma is huge. Winds of at least tropical-storm force covered 70,000 square miles — just larger than Florida’s entire land area.

Miami began feeling some of Irma’s winds on Saturday, with high-rise construction cranes sent spinning in circles.

Officials in other states also were preparing Saturday for Irma. South Carolina Gov. Henry McMaster issued a mandatory evacuation for some barrier islands, while Georgia Gov. Nathan Deal expanded the state of emergency to include 94 counties. FEMA warned Alabama and North Carolina also to be on watch.

Hurricane Jose looms

As Caribbean islands pummeled by Irma assessed damage — including shredded buildings, battered cars and submerged streets — hard-hit Barbuda and St. Martin wearily prepared for Hurricane Jose, which could hit impact those places this weekend.

Barbuda, one of two major islands in the nation of Antigua and Barbuda, was barely habitable for its 1,800 residents after Irma, with about 95% of its buildings damaged, Prime Minister Gaston Browne said, noting that repairs will cost $100 million.

Anguilla, Barbuda, St. Martin and St. Barts were under a hurricane warning for Jose, which could pass close to those islands Saturday. Voluntary evacuations were in place in Barbuda, Browne said.