- Tropical Storm Sally is expected to strengthen into a hurricane before striking the northern Gulf Coast.
- Sally’s slow movement will result in prolonged impacts on the Gulf Coast.
- Life-threatening storm surge is expected, particularly in parts of southeast Louisiana, Mississippi and Alabama.
- Flooding rain is a major threat from Sally on the Gulf Coast and farther inland across the Southeast this week.
- Damaging winds are expected near where Sally’s center crosses the coast.
Tropical Storm Sally is expected to intensify into a hurricane as it tracks into the northern Gulf Coast, where it will bring an extremely dangerous storm surge, flooding rainfall and damaging winds early this week. Sally will also pose a threat of flooding rainfall farther inland across parts of the Southeast.
Sally will produce a deadly duo of human-height storm surge and a foot or more of rainfall in parts of Louisiana, Mississippi and Alabama. Nearly 90% of deaths caused by hurricanes are the result of a combination of rainfall flooding, storm surge and rip currents.
Preparations for Sally’s impacts should be rushed to completion. Follow the advice of local officials if you are ordered to evacuate.
A hurricane warning has been issued for portions of southeastern Louisiana east of Morgan City, Louisiana eastward to the Mississippi/Alabama border, 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 and Tuesday.
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 Alabama and Florida, including Mobile Bay, 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 centered over 100 miles east-southeast of southeast Louisiana.
The storm is lopsided right now with much of its rain and thunderstorm activity off to the east of its center. Bands of rain and gusty winds will be on the increase in parts of the northern Gulf Coast through the day on Monday.
Timing, Intensity Forecast
Sally is expected to strengthen as it moves northwestward toward the northern Gulf Coast into Tuesday.
The system will arrive on the northern Gulf Coast beginning late Monday and Tuesday and could be a Category 1 hurricane as it nears landfall, according to the latest National Hurricane Center forecast. However, 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 will result in prolonged impacts from rainfall, storm surge and strong winds.
It’s important to note that impacts from Sally on the Gulf Coast will extend east of the forecast path depicted in the graphic below, including Alabama and the Florida Panhandle.
Here’s a look at what to expect.
Storm Surge, High Surf
A potentially life-threatening storm surge is expected along the northern Gulf Coast through midweek. This could be exacerbated by heavy rainfall occurring in areas experiencing storm surge.
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.
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, Mississippi and Alabama coasts is in the morning hours on Tuesday.
The peak storm surge will be near and to the right of where the center of Sally makes landfall, most likely Monday night through Tuesday. 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 there is a serious threat of life-threatening flooding rainfall.
Flash flooding and minor to locally major river flooding could occur from southeastern Louisiana into parts of Mississippi, Alabama and the Florida Panhandle this week.
Here is the latest rainfall forecast from the NHC.
-8 to 16 inches with locally up to 24 inches on the Gulf Coast from the western Florida Panhandle to southern Alabama, southern Mississippi and far southeast Louisiana into the middle of the week.
-6 to 12 inches is possible farther inland over portions of southeast Mississippi and Alabama.
Sally could eventually produce locally heavy rain as far north and east as north Georgia, east Tennessee and the Carolinas late this week. At least localized flash flooding is possible in these areas.
Flood watches have been issued by the National Weather Service in portions of the Florida Panhandle, southern Alabama, southern Mississippi and southeastern Louisiana.
Strong, damaging winds will impact the Gulf Coast near where Sally moves inland, particularly in southeast Louisiana, coastal Mississippi and coastal Alabama.
The winds could contribute to some 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.
There will be an increasing chance of isolated tornadoes from Sally later Monday, from southeast Louisiana to southern Mississippi, southern Alabama and the western Florida Panhandle.
The isolated tornado threat might continue on Tuesday and Wednesday in parts of these same general areas.
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