Transcript for Tropical Storm Sally takes aim at the Gulf Coast
We begin with the tropical threat taking shape, and taking aim at the gulf coast. Tropical storm Sally, already lashing south Florida with heavy rains and flash flooding. By tomorrow the system is expected to intensify to hurricane strength. Preparations are under way across Louisiana in low-lying grand isle. Residents ordered to get out. With concerns of a possible life-threatening storm surge, emergencies declared in Louisiana and Mississippi. We will time out the storm in a moment. But we begin with rob Marciano in biloxi. The power is going out right now. Reporter: Tonight, tropical storm Sally gaining strength, taking aim at the northern gulf coast. The storm hammering south Florida today with high winds and more than nine inches of rain, sparking flash flooding in the keys. Louisiana again on high alert. You got about 36 hours or so to really get yourself and your family ready for this storm. Reporter: Residents stocking up on supplies today, bracing for impact. Mandatory evacuations ordered for grand isle. Residents need to take this storm very, very, very seriously. You should be gathering your emergency supplies. Reporter: The entire gulf coast, including biloxi, will never forget what happened here 15 years ago with hurricane local leaders not taking any chances. The mayor of New Orleans issuing a state of emergency, and with 20 inches of rain and a life-threatening 11-foot storm surge, the city's levees will be tested. I recently got a firsthand look. And then there is this wall. New since Katrina, just east of New Orleans. Designed to keep any gulf surge out of the city. It is huge. 26 feet high and nearly two miles across. Rob, we saw what happened there 15 years ago with Katrina. This storm, not the same category. But it could still be a significant and dangerous weather event. Reporter: It does, Tom. A different storm, but a similar track to Katrina. But not nearly as strong. About 230 miles from where I am now. Hurricane warnings up from Mississippi through Louisiana. Forecasting for a cat 1 hurricane, from Mississippi, then weakening, slowing down, leading to a significant storm surge. 7 to 11 feet, and likely great in the way of rainfall. 15 to 20 inches, leading to flash flooding. All the while, hurricane Paulette will hit bermuda as a category 2.
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