Storm Team 15’s Adam Olivier Talks Tropical Depression 8

Tracking Tropical Depression Eight

Tropical Depression Eight is poised to bring heavy rain to Acadiana through the weekend.

Posted by Meteorologist Adam Olivier on Thursday, July 23, 2020


Tropics Update: This will be a long, in-depth post about Tropical Depression 8/Future Hanna, why rain chances could hang around next week, and Tropical Storm Gonzalo, so bear with me.

First, Tropical Depression 8 formed last night and continues to try to organize this morning. With warm Gulf waters, no dry air, and light wind shear, this is extremely likely to become Tropical Storm Hanna before landfall sometime around lunchtime Saturday.
There will be two main impacts to Acadiana: heavy rain and higher-than-normal tides. Overall, tides may rise to around a foot or two above normal, but significant flooding is not expected. The bigger concern will be the heavy rain threat, not only through the weekend, but also into early next week. We won’t see an all day, consistently heavy rain, and there will be plenty of breaks for the water to soak into the soil. The problems will come if we get multiple, heavy storms rolling over the same areas, or training. Models are indicating multiple rounds of heavy rain, but leave large breaks in between to allow some drying. This is a good sign, but things could still change, so pay close attention to the weather this weekend and remember: TURN AROUND, DON’T DROWN! Rain totals will *generally* range between two to four inches of rain around Acadiana, with the heaviest rains along the coast. This will change, though, based on the eventual path of the system and where the heaviest bands set up.

Looking ahead, an interesting pattern looks to set up early next week. Models are now thinking a piece of energy will be left over in the northern Gulf Sunday. At the same time, a dip in the jetstream will cause a break in high pressure in the upper levels of the atmosphere. This is shown in the pictures GFS/EURO Upper-Level Pattern. What this does is create a weakness that piece of energy to slowly move northward. As it does so, models are *hinting* at a weak area of low pressure forming close to the Louisiana coastline. This would serve as a focal point for more heavy rains to fall early next week. Depending on where high pressure breaks, this little feature could work its way inland closer to Acadiana. These differences are shown in the pictures labeled GFS/EURO models.
Of course, things will change in the coming days as models latch on to little features in the atmosphere, but just prepare for rounds of heavy rain to last through early next. The main thing to know is that we will be pretty wet this weekend, but it won’t be raining all the time. With many dry breaks expected, the flood threat exists but isn’t extremely high. Just take it easy this weekend and keep checking in on the weather.
Finally, Tropical Storm Gonzalo is going through some structural changes this morning. It is battling some dry air to its north and will continue to do so for the time being. However, it is expected to begin a strengthening phase later today and reach hurricane intensity. This would make it the first hurricane of the 2020 Atlantic Hurricane Season. As it moves westward, it is expected to maintain hurricane status as it moves through the Lesser Antilles and beyond. Past that, it is way too early to know anything about strength or path, so stay tuned for more updates in the future!

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