The 4PM advisory shifts Tropical Storm Sally’s latest track has shifted a tad east. Prepare for a significant weather event to unfold across southeast Louisiana and south Mississippi and south Alabama over the next 72 hours.
Max winds remain at 60 miles per hour. The system is still battling some northwest wind shear, which is keeping intensification steady rather than rapid. This is great news. Don’t turn your back on the system though, lets watch this trend closely. Forecast models showcase shear becoming less impactful later today and tonight, but this has yet to occur. The longer this shear impacts the system, the smaller the window will be for any stunt of more rapid intensification.
Landfall expected Monday night to early Tuesday morning as a strong Category 1 with max winds of 90 miles per hour. Do not use the phrase “only a category 1” with this storm. The system will be moving SLOW, which will exacerbate the storm surge, heavy rainfall, and wind impacts. Low-lying residents outside of levee protection, evacuate and leave. Do not stay.
7-11 feet of storm surge is projected from the mouth of the Mississippi to Ocean Springs, Mississippi. If you’re in Metro New Orleans, prepare for a potential hurricane strike. On it’s current track, this system will pose a significant rainfall threat with power outages likely. Flash flooding will be the bigger concern. Wind gusts of 65-85 possible on system’s current trek, along with 5-10+ inches of rainfall.
Localized 15-20″ amounts possible, especially just east of the New Orleans Metro from Slidell to the Mississippi Coast. Preparations need to be rushed to completion, as impacts will begin early Monday. Landfall will be very slow to occur Monday night through early Tuesday morning, which will exacerbate the flash flooding, wind, and storm surge impacts Monday until Wednesday.
Keep in mind, with this forecast path, 50 miles will make the difference in impacts. 50 miles further east would mean impacts in Louisiana will be FAR lower. 50 miles west, however, would mean much more significant impacts. It’s simply too early to call.
Below you will see the GFS brings most significant rain impacts into south Mississippi sparing NOLA Metro, while the Euro has the bullseye in southeast Louisiana and south Mississippi.