Transcript for Louisiana braces for impact as Tropical Storm Barry draws near
And we begin tonight with that major system bearing down on the U.S., the gulf bracing. Barry could become a hurricane, but that is just part of the concern tonight. Authorities say the Mississippi river has never been this high, with a storm this size coming. 20 inches of rain on the way. This is the satellite at this hour. Barry churning in the gulf. Mandatory evacuations have been ordered for part office the coast. Meteorologist rob Marciano leads us off from New Orleans. Reporter: Along the Louisiana coast tonight, thousands sandbagging and scrambling to evacuate ahead of tropical storm Barry. We're just hoping everything will be okay and life and property will stay safe. Reporter: In New Orleans, is hundreds of flood fleets are closed in and around the city. The mayor telling residents there to have a plan and be ready to shelter in place. You need to have at least 72 hours of food, water and medication for the whole family, including your pets. Reporter: Just a day after storms tore across New Orleans and flash flooding swamped this city in just a few hours, Louisiana is facing a new threat for the first time. A potential hurricane roaring ashore while the Mississippi river is still at flood stage. Swollen by months of flooding upstream. This is going to be a major weather event for a huge portion of the state of Louisiana. And everyone needs to pay attention to the track. Reporter: New Orleans sitting below sea level is the most vulnerable. Miles of these levees protect this city, but look how close the water already is to the top, and this wind is only going to get worse. Hurricane storm surge pushed upriver, essentially stopping the flow, lifting the levels and potentially sending water right into downtown. The army corps of engineers says though the roughly 20 foot high levees may be overtopped, they will not fail, nor should the flood walls, improved after Katrina. We're confident that we are not going to have a duplicate of Katrina. However, if you have a storm that has elevations much higher than those floodwalls, you're going to get water in the city. Reporter: David, officials obviously preparing for the worst. Those Katrina upgrades are going to be tested with this storm. And there's still a fair amount of uncertainty when it comes to the intensity of this storm. That said, hurricane warnings have been posted as we come on the air across the Louisiana coastline. Tropical storm warnings up for New Orleans. The center is just less than 100 miles offshore a little bit bottom heavy. Dry air to deal with. But water temperatures are in the upper 80s. We expect to see intensification. 60 miles an hour tomorrow afternoon. Making landfall Saturday morning. Three to six feet of storm surge. So, this river level is going to come up, but the rainfall will be in excess of two feet. So, we will see flood issues here and in towns well inland. David? Rob Marciano leading us off tonight. Rob, thank you.
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