waters are rising and the map says it all. Now mar than half the country under threat of froods, including flash floods. And abc's meteorologist ginger zee shows us how fast they happen. Reporter:... See More
waters are rising and the map says it all. Now mar than half the country under threat of froods, including flash floods. And abc's meteorologist ginger zee shows us how fast they happen. Reporter: Underwater. Again. The latest flash flooding, fatal in oklahoma. Too much rain too fast, swamping this walmart in cortland, new york. Look at the store before. And the image tweeted by the weather service after. More than 5 inches of rain falling in just hours. Emergency crews had to use boats to rescue about 50 people from inside the store. Reporter: The rushing waters swamping farms in kansas, invading linda's home in tennessee. You try to do everything you can and keep getting hit like this. Reporter: And here. This crane stuck on a shrinking island in missouri. And -- there it goes. There it goes. Oh, no, no, no, no. Here they come. Oh, my god, here they come. I'm excited. Reporter: While the rescues have been heroic. In the last week, at least four lives have been lost to flash floods. The "flash" in flash flooding, the perfect description. It is in and out in a flash. It all depens on where you are. In the city, the kcement means water has nowhere to go. As quickly as it comes, it goes. Leaving an even nastier mess behind. The aftermath seems to be worse than the actual occurrence. Reporter: And it's not over. Let me show you the next 4 hours. The areas near jonesboro going to pick up 2 inches. Nashville, atlanta, birmingham all on alert this weekend. 48 hours. A wet two days coming up. Before we move on, we want
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