Slow-moving Hurricane Sally was dumping heavy rainfall over parts of the Gulf Coast on Tuesday, hours before the storm was expected to bring an even greater deluge when it makes landfall as a Category 2 hurricane or strong tropical storm near Mobile, Alabama.
The National Hurricane Center warned of "extreme life-threatening" and "historic" flash flooding along the northern Gulf Coast. Sally was upgraded to a Category 2 hurricane at midnight, and the center said it had sustained winds of 100 mph.
The storm Tuesday night was 65 miles south of Mobile, whipping up maximum sustained winds of 85 mph. Landfall was expected between Mobile and Gulf Shores, Alabama, between 4 a.m. and 8 a.m. Wednesday, according to NBC News meteorologist Bill Karins.
The storm was only moving at 2 mph and wasn't expected to speed up much before making landfall with lingering rainfall that could last up to two days. In an update Tuesday night, the center described the hurricane's progress as "creeping."
Some areas from the western Florida Panhandle to far southeastern Mississippi could see up to 30 inches, according to the NHC. The center predicts water heights of 6 to 9 feet from Ocean Springs, Mississippi to Dauphin Island, Alabama, if peak surge coincides with high tide.
Rain fell sideways and rain began covering roads in Pensacola, Florida, and Mobile, Alabama. A curfew was ordered in the coastal Alabama city of Gulf Shores. President Donald Trump approved Florida's request for a federal disaster declaration, which will allow taxpayer assistance to go to victims in impacted counties.
Up to a foot of rain had fallen already on the coast by Tuesday night and Sally’s lumbering pace meant there would likely be extended deluges. More than 60,000 homes and businesses also lost power in coastal Alabama and western Florida Panhandle as conditions deteriorated.
“A hurricane moving at 2 mph is stalled for all intents and purposes,” said Brian McNoldy, a hurricane researcher at the University of Miami. “If they aren’t moving along and they just kind of sit there, you’re going to get a ridiculous amount of rain.”
“This is the real deal, and it deserves your attention,” Mississippi Gov. Tate Reeves wrote on Twitter. “Be smart. Prepare for worst. Pray for the best."
Louisiana Gov. John Bel Edwards on Tuesday said New Orleans was no longer a direct target of Sally.
"Good news to report today as it relates to hurricane Sally, and that is that the track has continued to shift eastward," he said. "That really has been the case, since Sunday morning when it looked like the Greater New Orleans metro area was in for a direct hit from Sally."
The city of New Orleans said in a statement, "Significant impacts from Hurricane Sally are no longer anticipated in the local area."
President Donald Trump tweeted late Monday that he was closely monitoring “extremely dangerous Hurricane Sally." Trump urged residents to “be ready and listen to State and Local Leaders!” Earlier Monday, the president issued an emergency declaration for parts of Louisiana, Mississippi and Alabama, an action that authorizes federal emergency officials to coordinate disaster relief efforts and provide emergency assistance to the affected areas.
Alabama Gov. Kay Ivey thanked the president "for approving our request so quickly."
"We will continue closely monitoring the developments today, and I urge everyone in the coastal areas south of I-10 and in low-lying areas to take all precautions and heed advice from weather experts and local officials. Please stay vigilant, Alabama," Ivey said.
"I urge you in the strongest way possible to evacuate and seek shelter as this storm makes landfall tonight," she urged residents Tuesday.
Mobile Mayor Sandy Stimpson pointed out that the grounds were already saturated from weeks of rain, which would increase flooding. He said damage from wind "is going to be unbelievable" since the languid storm would essentially be parked over areas.
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In Florida, Gov. Ron DeSantis declared a state of emergency in the Panhandle's westernmost counties, Escambia and Santa Rosa, as the hurricane's outer bands began to lash the area.
Eric Gilmore, head of Escambia County's Division of Emergency Management, said evacuations in Pensacola Beach and other low lying areas were voluntary for now.
"Do what you need to do now to get out of harm’s way," he said at news conference on Tuesday afternoon. "We’re expecting 3 to 5 feet of storm surge now."
Escambia was one of 13 counties newly covered by the governor's expanding emergency declaration.
The Florida Department of Transportation closed Pensacola Bay Bridge, which connects Gulf Breeze to Pensacola, after a barge struck the crossing, according to state and local officials. State inspectors were expected to assess the damage when it's safe to do so.
Sally has lots of company during what has become one of the busiest hurricane seasons in history — so busy that forecasters have almost run through the alphabet of names with 2 1/2 months still to go.
For only the second time on record, forecasters said, five tropical cyclones swirled simultaneously in the Atlantic basin at one point on Monday. The last time that happened was in 1971.