- Tropical Storm Sally is expected to strengthen in the Gulf of Mexico.
- Sally is forecast to become a hurricane before landfall.
- Life-threatening storm surge is also expected, particularly in parts of Louisiana and Mississippi.
- Flooding rain is a major threat from Sally on the Gulf Coast.
- Damaging winds are expected near where Sally’s center crosses the coast.
Tropical Storm Sally is expected to strengthen into a hurricane and bring an extremely dangerous storm surge, flooding rainfall and damaging winds to the Gulf Coast beginning on Monday.
Sally could produce the deadly duo of human-height storm surge and a foot or more of rainfall in parts of Louisiana and Mississippi. Nearly 90% of deaths caused by hurricanes are the result of a combination of rainfall flooding, storm surge and rip currents.
Now is the time to prepare for Sally’s impacts. Follow the advice of local officials if you are ordered to evacuate.
A hurricane warning has been issued from Morgan City, Louisiana, to Ocean Springs, Mississippi, including Lake Pontchartrain, Lake Maurepas and metropolitan New Orleans. Hurricane conditions (winds 74 mph or greater) are expected in some parts of this area by late Monday.
Hurricane watches and tropical storm warnings and watches are in effect to west and east of this hurricane warning, including parts of Louisiana, Mississippi, Alabama and the Florida Panhandle.
A storm surge warning is also in effect from Port Fourchon, Louisiana, to the border between Mississippi and Alabama, including Lake Pontchartrain, Lake Maurepas and Lake Borgne. This means there will be a danger of life-threatening inundation from storm surge within the warning area in the next 36 hours.
Sally is producing rain and thunderstorms over western Florida at this time.
The storm brought flooding rainfall to parts of the Florida Keys on Saturday. Some areas in the Keys picked up nearly a foot of rainfall.
Timing, Intensity Forecast
Sally is expected to strengthen as it moves northwestward toward the northern Gulf Coast early this week.
The system will arrive on the northern Gulf Coast beginning late Monday and Tuesday and could be a Category 1 or 2 hurricane as it nears landfall, according to the latest National Hurricane Center forecast. There is uncertainty in this intensity forecast, so stay alert for possible changes.
Sally will likely slow down near the coast of Louisiana and Mississippi on Monday night into Tuesday. That slow forward speed could result in prolonged impacts from rainfall, storm surge and strong winds.
Here’s a look at what to expect.
Storm Surge, Damaging Surf
A potentially life-threatening storm surge is expected along the northern Gulf Coast from Monday through at least Tuesday.
The highest storm surge of 7 to 11 feet is expected from the mouth of the Mississippi River to Ocean Springs, Mississippi, including Lake Borgne. Storm surge could be 4 to 6 feet in southeast Louisiana’s Lake Pontchartrain and Lake Maurepas.
Below is a look at the storm surge forecast for the Gulf Coast if peak surge occurs at the time of high tide. High tide along the Louisiana and Mississippi coasts is in the morning hours on both Monday and Tuesday.
The worst storm surge will be near and to the right of where the center of Sally makes landfall. Large waves could worsen the storm surge impacts in some areas and cause significant beach erosion on much of the northern Gulf Coast.
Sally is expected to slow down on approach to the Gulf Coast, which means flooding rainfall is likely.
Here is the latest rainfall forecast from the NHC.
-1 to 3 inches with locally up to 6 inches in southwestern Florida through Monday.
-6 to 12 inches with locally up to 20 inches on the Gulf Coast from the western Florida Panhandle to far southeast Louisiana from Monday into the middle of the week.
-4 to 8 inches is possible farther inland over portions of Mississippi and Alabama.
Sally could eventually produce locally heavy rain as far north and east as north Georgia, Tennessee and western North Carolina later this week, however, details are uncertain.
This rainfall could trigger serious flash flooding and river flooding in some of these areas.
Flood watches have been issued by the National Weather Service in portions of Florida, southern Alabama, southern Mississippi and southeastern Louisiana.
Strong winds will impact the Gulf Coast near where Sally crosses the coast later Monday into Tuesday.
The winds could contribute to structural damage, downed trees and power outages.
Here is the latest wind gust forecast. Changes to this forecast are likely depending on the exact future track and intensity of Sally.
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