Powerful winds are slamming the Gulf Coast as Hurricane Sally takes aim, forecast to make landfall near Mobile Bay, Alabama, as a Category 1 hurricane Wednesday morning.
Up to 30 inches of rain is possible.
Wind gusts have already surpassed 60 mph off the Louisiana coast.
Hurricane warnings are in effect in Biloxi, Mississippi, Mobile, Alabama, and Pensacola, Florida.
Mobile to Pensacola will experience wind gusts up to 70 mph Tuesday night.
Because Sally is barely moving, the heavy rain is forecast to last for hours, causing dangerous flooding.
East of Biloxi will get the worst of the rain and flooding.
Storm surge may reach 4 to 7 feet in Mobile Bay, and 4 to 6 feet in eastern Louisiana. Pensacola and Biloxi could see 3 to 5 feet of storm surge.
The gusty winds and heavy rain will continue from Mobile to Pensacola and into Panama City before spreading north into Alabama through the day Wednesday.
South and central Alabama may get over 15 inches of rain.
As Sally moves across the Southeast states, the winds will be weaker but the heavy rain remains a concern. Six to 12 inches of rain is forecast for Montgomery, Alabama, and Atlanta through Friday morning. Even the Carolinas will see rainfall.
Florida police on Tuesday began closing the Pensacola Bay Bridge, which connects Pensacola with Pensacola Beach.
"We urge you to stay home and off the roadways if you can," Pensacola police said.
Alabama Gov. Kay Ivey ordered beaches closed Monday afternoon and said she was "recommending an evacuation, especially of non-residents, and those living in flood-prone areas south of I-10."
"Sally is shaping up to be a very dangerous and historic flooding event," Brian Hastings, director of the Alabama Emergency Management Agency, said Tuesday. "If you are in a low-lying area or a flood-prone area, get to a safer place."
In Hancock County, Mississippi, officials ordered a mandatory evacuation for low-lying areas.
In Biloxi, Mississippi, casino resorts were ordered to close.
"We have two concerns," Biloxi Mayor Andrew Gilich said Monday. "First, that our residents are taking this seriously and have made preparations, and second, that this is a slow-moving storm, which means we'll see heavy flooding along the front beach and in low-lying areas, especially along the rivers and Bay."
"Residents need to have a plan and follow that plan," he said.
Sally is the seventh hurricane so far this season; the average at this time is six.
Sally will be third hurricane making landfall along the Gulf Coast this season.
The storm will also be the fourth hurricane to make landfall in the U.S. this season. The last time the nation had more than four hurricanes to make landfall was in 2005 when there were five, including Hurricane Katrina.
This report was featured in the Tuesday, Sept. 15, 2020, episode of “Start Here,” ABC News’ daily news podcast.
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