Transcript for Hurricane Irma prompts mass evacuations in Florida
Irma. A modest name for this monster of a storm. She has killed already. And there is little doubt she will kill again. Her record-high winds have ravaged and punished the caribbean for days. She is now taking dead aim at Florida. Where over 5 million people are under mandatory evacuation orders. Anywhere in the state if you're told to evacuate leave. Get out quickly. Do not put yourself or your family at risk. Reporter: The city of Miami now eerily quiet. A ghost town as they brace for the storm. The path of destruction left behind in the caribbean, a forewarning of hurricane Irma's strength. At least 22 people have died. This tropical paradise now a ghoulish reminder. Whenever man and mother nature meet, it's a mismatch. The island of barbuda, practically uninhabitable. This has been one of the worst days of my life. The entire country has been decimated. I have never seen anything like this before. Reporter: The high winds reduced buildings to piles of rubble in St. Martin and gutted them in the British virgin Islands. Last night hurricane Irma hit the island of Turks and caicos. Survivors witnessing rolling blackouts, shredded rooftops and flooded streets. We have seen nothing but the worst in the last hour and a half. Reporter: Tourists barricading doors, even hunkering down in bathrooms. Then all of a sudden you're calling to say good-bye in case you don't have a chance to. Reporter: By daylight an agonizingly familiar scene left in the wake of Irma. The Bahamas is next in the path. We started to feel the first gusts move in as those outer bounds cover the Bahamas. Families are now hunkering down in hotels. People going out to buy provisions. Because there are no flights in or out of the Bahamas now. Reporter: Stateside on the only road out of the keys traffic has been bumper to bumper from the bottom of the state all the way up through Orlando. Our Matt Gutman was there. Where are you coming from? Miami. How long has it taken you? We left at 1:00 in the morning. Did you expect it to be this bad? No. Reporter: A drive that would normally take a little three hours now spanning eight to nine hours. It's got zone bad people are abandoning their cars because they've run out of gas. Now, what you can see is a traffic jam that stretches all the way to the horizon. What you can't see is that it's tens of miles long. In miami-dade county, where nearly 40% of gas stations in the area have run out of fuel, the largest evacuation in that county's history is under way. Matt caught a ride with one of the fuel truck drivers. How are you? We've been working around the clock since Monday. Wow. When you finally deliver the gas, are people very happy? Yeah. They give me presents. They give you presents. They give me lunch, dinner. Reporter: A hero's welcome for the drivers providing much-needed fuel. But even they are stopping soon. This is the last tanker to lead fort everglades. Heading up to fort pierce. After this there are no more tankers filled with gas filling up these stations. Folks are going to have to get out of the state without any help. Reporter: Others flooding airports, taking to the air to escape the coming storm. This map showing hundreds of flights leaving Florida this morning. But by this afternoon over 4,600 flights had been canceled. Tonight the terminal nearly empty. A few lucky ones making it out on the remaining flights. Did you plan ahead in did you get a last-minute ticket? I got a last-minute ticket late this afternoon. Reporter: But so many here with no flight home. Karen morevo tells my colleague Amy robach that she's stranded in Miami after a layover. You don't have your bags. No. You just have this. And now you're being bused to a shelter. Yes. That has to be incredibly overwhelming. Yes. Reporter: For the locals who didn't leave a run on supplies to keep the power on. And the storm out. I think it's going to be worse than Andrew. Reporter: Arnoldo richuli is staying to protect his home, but his family told our Tom llamas they want to evacuate. What's making you want to leave, possibly leave your dad behind? Well, because of the storm surge. I'm trying to actually not leave him, trying to bring him with me. Let's go up to Gainesville away from all these storm surges. But he doesn't want to go? No. Reporter: A major concern for Miami's infrastructure, its glass towers and the cranes that built them. Those are big targets out there. Again, we're going to lose buildings that are going to have to be repaired. But I don't think buildings are going to completely collapse. Reporter: 25 cranes have been secured. Those that live near them told to evacuate. Developers and builders maintain that the buildings in downtown Miami are safe from Irma's punishing winds. But they caution that high-rises could sway up to 12 inches. Being in a high-rise you're less likely to get hit by debris on the ground. But high up, 50 floors up like we are right now, there's another danger. The wind up here is much more powerful. Reporter: Hurricane researchers say the higher up you go the faster the wind. A category 4 hurricane with winds at 140 miles per hour could be up to 220 miles per hour on the 50th floor. But the greatest damage could well be down on the first floor, where Irma's expected to cause a massive storm surge. Storm surge here could easily be up and over my head. This is one of many marineas that line the city of Miami, a massive city that is pinned up against the water. And extremely susceptible to hurricane storm surge. Reporter: The areas in yellow would be underwater with only a three-foot storm surge. The latest forecast now predicting a storm surge of up to ten feet in Miami. That would mean all the areas in red would be underwater. With hurricane-force winds extending up to 70 miles outward from the center, Irma already dwarfs the size of hurricane Andrew, which devastated the region in 1992. I've lost everything I own. Reporter: Andrew made landfall as a category 5 storm, leaving hundreds of thousands homeless. It took 25 years to build. It took an hour or two hours and a half to destroy. Reporter: But Irma's magnitude might surpass that historic storm. It's forecast to make 4r57landfall early Sunday morning losing strrnt up the coast and lingering in Atlanta and Jacksonville on Tuesday. And Irma is not alone. There are two other hurricanes in the atlantic basin. Katya currently a category 1 storm has just made landfall in Mexico's southern gulf coast. And category 4 Jose, seen in this international space station image earlier today, is forecast to come close to barbuda and the other caribbean islands that Irma battered days ago. Meanwhile, former presidents Carter, Clinton, Obama, and presidents bush 43 and 41 teaming up to start a fund for Harvey victims. As former presidents we wanted to help our fellow Americans begin to recover. Thank you. Reporter: And today our current president offering support for those in Irma's path. We're very prepared. We're prepared at the highest level. Reporter: In the sunshine state the hurricane flags are up and sand from the beaches no longer part of the scenery. It's being bagged and put into use as residents hunker down in their homes. And lines to get inside Miami shelters swell. Up Florida's northern coast and up to South Carolina the warning to evacuate echoes. And we understand it's not convenient. But this is not -- evacuations are not about convenience. They're about making sure that you're safe. Reporter: For those still in the storm's path time to evacuate is almost over. Fearless, foolish or simply without options, they will soon face Irma. Thus far she is undefeated. And for breaking news alerts on hurricane Irma you can download the ABC news app.
This transcript has been automatically generated and may not be 100% accurate.