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 110 miles south of Mobile, Ala., which lies near the middle of its potential landfall zone, the NHC said in its 11 a.m. ET update.
Federal emergencies have been declared in Mississippi, Alabama and Louisiana, with President Trump approving disaster requests from those states' governors.
The center of the hurricane will get very close to 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.
A tropical storm warning for New Orleans was lifted Tuesday morning, providing relief in a city that is sheltering people who fled Hurricane Laura's disastrous arrival in the Lake Charles area weeks ago.
TROPICAL UPDATE: @NOAA's #GOES16🛰️ is closely tracking #HurricaneSally this morning. As of 8 am ET, its winds were 85 mph, making it a Cat-1 #hurricane. @NHC_Atlantic says that historic flooding & life-threatening flash flooding are likely from #Sally. https://t.co/VTAp4gGkHs. pic.twitter.com/rpb0YpBwDK— NOAA Satellites - Public Affairs (@NOAASatellitePA) September 15, 2020
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.
"Historic flooding is possible with extreme life-threatening flash flooding likely through Wednesday," the hurricane center said.
Sally's projected landfall has shifted consistently toward the east; the warning area now centers on the middle of Alabama's Gulf Coast, extending from Biloxi, Miss., eastward past Pensacola. A large part of the coast is under a storm surge warning, from the New Orleans area to the western Florida Panhandle.
The storm's rain, combined with a storm surge of up to 7 feet, are expected to produce dangerous floods. Forecasters reduced their storm surge predictions late Tuesday morning, after earlier projecting a surge of 9 feet.
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 is currently moving northwest, but its path is expected to curl northward today and then a bit to the east. The timing of those maneuvers is uncertain, leaving its projected path in doubt as people rush to prepare for strong winds and high water.
After Sally makes landfall, flooding risks will spread further inland, eventually reaching northern Georgia and the western sections of South Carolina and North Carolina later this week, forecasters say.
Sally rapidly strengthened on Monday, with sustained winds of 100 mph. That 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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