Transcript for Families in Upper Midwest bracing for 2nd night of severe storms
But we do begin tonight with the horror that played out as three ef-2 tornadoes ripped through the center of the country. They were all part of at least 11 reported tornadoes in just the past 24 hours. The massive twister in Wyoming. Sioux Falls, South Dakota, hit especially hard. Those three ef-2s confirmed inside the city. Winds of at least 125 miles an slamming into a hospital. Doctors and nurses had just minutes to wake up patients, to get them to safety. And tonight, major questions about why some of the city's sirens did not go off. Officials now say it was human and all of this, as we now watch yet another tropical disturbance that could cause trouble for the U.S. ABC's Alex Perez leading us off tonight from Sioux Falls. Reporter: Tonight, families across the upper midwest bracing for a second night of severe storms. Oh, god, it hit something! Reporter: Nearly a dozen twisters reported in the last 24 hours. The dangerous weather striking South Dakota's largest city in the middle of the night. Tornado sirens sounding the alarm in Sioux Falls. There are 77 of them across the city, but officials say not all of them were activated, blaming human error. At least three twisters touching down in the city, all ef-2s. The one striking this hospital campus had winds up to 130 miles an hour. Our staff was courageous. They had ten minutes to wake up 102 residents, get them to the center of the building and all are safe and sound. Reporter: Another ef-2 twister quickly tearing through this shopping complex. Total devastation in just 60 seconds. This woman's business destroyed. We can start over. Nobody was hurt. And that's really all that counts. Reporter: Powerful winds sending a tree crashing onto Charles' home. I mean, this is multiple 100-pound tree and I'm surprised the house didn't go down. Reporter: Residents here worried, watching the skies for more possible tomorrows tonight. And Alex joins us now from Sioux Falls. He's live tonight. And Alex, after all they have already been through, we know more storms are possible there tonight? Reporter: Yeah, David, we've already had some rain push through here. I want you to look behind me here. You have the see how powerful the winds were, completely destroying this auto parts store. Basically a shell of a building here. And with more storms on the way, officials here say they are taking steps to make sure those problems with the sirens don't happen again. David? Alex Perez leading us off tonight. Alex, thank you. Let's get right to meteorologist rob Marciano, tracking it all, watching the severe weather into the night and, of course, that new tropical threat. Rob? Reporter: Good evening, David. The atmosphere primed again in the midwest and Sioux Falls is right there, along the stationary boundary. Storms expected to fire there and across Madison, Detroit, Michigan. Minneapolis, you'll see storms in the morning. We have three disturbances in the atlantic. One is close and forecast to get into the gulf of Mexico. At the very least, we'll see heavy rain for Florida and much of the gulf coast states. More details to come on this tomorrow. David? Rob Marciano, thank you. And we're going to turn
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