Transcript for Florida prepares for Irma after Turks and Caicos devastated by storm

Irma as we all know continues to move towards south Florida. Expecting to see dangerous winds by tomorrow there. And the storm expected to make landfall on Sunday. "World news tonight" anchor David Muir is leading our coverage on the ground all weekend and he's here with us this morning. Good morning, David. Reporter: Robin, good morning to you. As you heard ginger point out, south Florida and all of Miami now bracing for a category 4 hurricane. A direct hit, winds up to 150 miles per hour or more and as ginger pointed out the real concern here the storage surge. Several feet up to ten feet high perhaps and one of the most troubling things about this hurricane is that right now some of the most populated areas of south Florida and here in Miami, it's expected it'll be on the wrong side, the most damaging side of this hurricane, so we are watching it very closely obviously and overnight:00 A.M. Our phones went off with official hurricane warnings now in place for Miami and south Florida. Overnight we're getting word of catastrophic damage in the Turks and caicos being on the wrong side of the hurricane churning as we wait for more images there. New images from the U.S. Military now involved in the caribbean. U.S. Navy sailors helping the critically injured bringing them to St. Croix and the U.S. Virgin Islands for treatment. Pictures from St. Martin. That could be hit again unfortunately by hurricane Jose which is next in the pipeline. Hotels destroyed. An estimated 6,000 Americans actually still stuck there. I talked to the prime minister of barbuda who said more than 90% of that island simply destroyed. Hotel, buildings gone and told me the effort there today is to simply get everyone on that island off. To evacuate the entire island before Jose hits again. For late details on Turks and caicos and reports of calls from Americans who were there back home to their family, let's turn to ABC's James Longman live from Nassau. James, good morning. Reporter: Good morning, David. These tiny islands are dealing with one of the biggest hurricanes they've ever seen and no matter what the preparations this monster storm is causing huge damage. The latest to be swallowed by Irma. Turks and caicos devastated overnight. A small island to nearly 35,000 people battered are rolling blackouts. Shredded rooftops and flooded streets. We have seen nothing but the Khat in the last hour and a half. Reporter: Is 65-mile-per-hour winds ravaging this hotel. The thought of needing a life jacket is not the most comforting thing. Reporter: Tourists barricading door, even hunkering down in bathrooms. Made two bunkers. One in here and one in here. It's only getting worse. Reporter: Using anything to keep out of danger. Colorado native Kelsey priest broke down in tears after speaking to her family back home as Irma loomed over the island. All of a sudden you're calling to say good-bye because Y you might not have a chance to. Reporter: Islands across the caribbean dealing with the aftermath of the 600-mile-wide storm. Look at the level of devastation in St. Martin. Homes leveled. These shipping containers tossed. Boats slamming together like toys. In barbuda, which has been completely decimated by Irma, volunteers evacuating stranded islanders by private yacht. We're here in the Bahamas where landfall is expected sometime tonight. The wind is picking up here and the thing is, these islands sit very, very close to the water so the worry is that storm surge coming in, David. All right, you and the crew stay safe. We appreciate it. Back here in Florida this morning, we should point out all public schools in Miami have been closed trait through Monday at least. That's the word this morning and I got to tell you coming out to this live report for "Gma" this morning, before the sun even came up, we passed several line, all you could see were the taillights of cars lining the roads here, people lined up already this morning throughout south Florida trying to get gasoline and as you know we've been reporting for a couple of days about the shortage of gas, some gas stations already running empty. We'll talk about that with the governor in a little bit, David. Thank you.

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