Hurricane Sally weakened a bit over night, but the storm brings a perilous threat of floods to areas along the northern Gulf Coast, forecasters say. The hurricane is crawling along at just 2 mph, giving its heavy rains even more potential impact. A tornado watch has also been issued.
"Because of that slow movement, we're going to see torrential rainfall, a dangerous amount of rainfall," National Hurricane Center Director Ken Graham said in an online briefing Tuesday morning.
Many communities in Sally's path will be drenched by 10-20 inches of rain, with some areas possibly seeing up to 30 inches.
"That's just a history-making amount of rain," Graham said.
Hurricane Sally has maximum sustained winds of 85 mph and is about 105 miles south-southeast of Biloxi, Miss., which is in the western half of its potential landfall zone, the NHC said in its 8 a.m. ET update.
The center of the hurricane will pass near southeastern Louisiana's coast on Tuesday, but it's expected to make make a sharp turn toward the north before making landfall in Mississippi or western Alabama tonight or Wednesday morning, forecasters say.
Parts of the western Florida Panhandle and Alabama are now seeing tropical storm conditions, and the situation is expected to deteriorate. Those same areas are included in a tornado watch bulletin the National Weather Service issued Tuesday.
The storm's rain, combined with a large storm surge, are expected to produce dangerous floods.
"Historic flooding is possible with extreme life-threatening flash flooding likely through Wednesday," the hurricane center said.
A storm surge warning, meaning there is a danger of life-threatening inundation by waters along the coast, is in effect from the mouth of the Mississippi River to the Okaloosa/Walton County line in Florida. The advisory also includes Mobile Bay.
Sally's projected landfall has shifted consistently toward the east; the center of the warning area is now just east of the Mississippi/Alabama border. But a large part of the coast is under a storm surge warning, from New Orleans to east of Pensacola, Fla.
Sally is currently moving northwest, but its path is expected to curl northward today then a bit to the east – and the timing of those maneuvers is uncertain, leaving its projected path in doubt as people rush to prepare for strong winds and high water.
Sally rapidly strengthened on Monday, with sustained winds of 100 mph. Thast prompted forecasters to say it could have winds of up to 110 mph when it makes landfall. Those estimates have now been lowered, and the storm is expected to be a Category 1 storm when it finally arrives.
Sally is expected to remain at tropical storm strength or higher until the early hours of Thursday morning.
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