Sally is expected to make landfall between southeastern Louisiana and the Mississippi-Alabama border late Tuesday or early Wednesday
In its 10 a.m. CDT update, the NHC said Sally was 55 miles east-southeast of the mouth of the Mississippi River and 110 miles southeast of Biloxi, Miss. It had maximum sustained winds of 85 mph and was moving northwest at 2 mph.
The center said the Category 1 hurricane is “crawling” toward the U.S. Gulf Coast.
“On the forecast track, the center of Sally will pass near the coast of southeastern Louisiana today, and make landfall in the hurricane warning area late tonight or Wednesday,” the NHC said.
The advisory said Sally could bring “historic flooding” and “extreme life-threatening flash flooding” along portions of the northern Gulf Coast.
The NHC has issued a hurricane warning from east of Bay St. Louis, Miss., to Navarre, Fla.
“Although little change in strength is forecast until landfall occurs, Sally is still expected to be a dangerous hurricane when it moves onshore along the north-central Gulf coast,” the NHC added.
President Donald Trump said late Monday his administration is monitoring the storm.
“We are fully engaged with state and local leaders to assist the great people of Alabama, Louisiana and Mississippi,” he tweeted. “Be ready and listen to state and local leaders!”
The president has approved federal emergency declarations for Louisiana, Mississippi and Alabama.
New Orleans Mayor Latoya Cantrell issued a mandatory evacuation order for areas outside the city’s levee system.
Sally is the earliest named “S-Storm” to ever form in the Atlantic Ocean basin, beating out Hurricane Stan, which was named on Oct. 2, 2005.
Downpours were expected across Louisiana, Mississippi and Alabama into the storm’s arrival. Roads may become impassable due to flooding and some communities may become cut off from first responders and medical services for a time.
Between the potential threats closer to home and many others emerging from the depths of the basin, an unusual occurrence that hasn’t happened since September of 1971 may unfold in the coming weeks. As many five named tropical systems may spin across the ocean at the same time by the middle of September.
Tropical storms and hurricanes can form well beyond the statistical peak of hurricane season, which is Sept. 10-11.
Hurricane season does not officially end until the end of November, and named systems could emerge into December this year.
Once the list based on the English alphabet is exhausted, Greek letters will be assigned as names, and that has only happened one other time in history, in 2005.