Hurricane warnings have now been issued from Morgan City, Louisiana, east to Ocean Springs, Mississippi, including New Orleans, Lake Pontchartrain and Lake Maurepas. Sally continues to strengthen across the Gulf of Mexico with sustained winds of 60 mph.
Storm surges of up to 7 to 11 feet are possible near the center of the storm and just east of where landfall is expected. Along with storm surge, extreme rainfall amounts of over a foot are expected in some locations between southeast Louisiana and the western Florida panhandle.
Louisiana Gov. John Bel Edwards declared a state of emergency Saturday evening ahead of Sally’s arrival.
“While we ultimately don’t know where Sally will make landfall, much of Southeast Louisiana is in the storm’s cone and the risk of tropical storm force or hurricane strength winds continues to increase. This storm has the potential to be very serious,” Edwards said in a news release.
In New Orleans, Mayor LaToya Cantrell issued a mandatory evacuation order for residents outside of the city’s levee protection system. The evacuation will begin Sunday at 6 p.m. for the areas of Venetian Isles, Irish Bayou and Lake Catherine.
In coastal Louisiana, Grand Isle is under a mandatory evacuation, and a recommended evacuation notice went out to the community of Port Fourchon.
Gulf Coast expecting 6 to 12 inches of rain
Flash flood watches are in effect along the Gulf Coast across much of southern Louisiana, east to the Florida Panhandle, and along the western Florida peninsula. These watches include the city of New Orleans, Biloxi, Mississippi, Mobile, Alabama, and Panama City and Tampa, Florida.
Sally is expected to slow in speed as it approaches the Gulf Coast which will result in significant flash flooding across the region. Widespread rainfall totals of 6 to 12 inches is expected along the Gulf Coast through Wednesday, but isolated rainfall of up to 20 inches is not out of the question.
The combination of extreme rainfall and the high storm surge will bring widespread flooding to much of the Gulf Coast beginning on Monday and lasting at least through Wednesday.
Most forecast models have Sally moving toward the northern Gulf Coast and likely making landfall somewhere between New Orleans and Panama City by late Monday or Tuesday. However, if the track shifts farther west or slows down, landfall may hold off until Wednesday.
Once it reaches that area of the Gulf Coast the steering patterns break down and the system meanders near the coast.
Whether the meandering is offshore prior to a landfall or onshore will not make much of a difference in terms of rainfall. In either case, because of the slow forward movement along the Gulf Coast significant flooding is possible.
Active hurricane season stays busy
Another system, Tropical Depression Twenty, formed in the central tropical Atlantic on Saturday, according to the NHC. Twenty has sustained winds of 35 mph.
Twenty is expected to strengthen to a tropical storm by Sunday evening and a hurricane by Tuesday, and if so, will be named Teddy. The previous record for the earliest 19th named storm is October 4, 2005.
Many storms broke records for being the earliest named to date. All but three named storms (Arthur, Bertha and Dolly) set records for being the earliest named storm for their respective letter. After Sally, there are only three names left on this year’s official list: Teddy, Vicky, and Wilfred. After that, the NHC will move on to using the Greek alphabet.
Sally is just one of several systems in the Atlantic. The NHC is currently watching seven areas: one hurricane, one tropical storm, two tropical depressions and three tropical disturbances. Thursday marked the peak of the Atlantic hurricane season.
Hurricane Paulette is forecast to track toward Bermuda and potentially make landfall early Monday morning as a category 2 storm. A hurricane warning is in effect for Bermuda and hurricane conditions are expected tonight.