More to watch in the tropics while Laura’s flood threat continues

Hurricane Laura landfall site.
Hurricane Laura landfall site. (WPLG)

There are two tropical disturbances of note in the tropical Atlantic, and more in the pipeline. There have been so many named storms this year that it’s hard to remember that we are still two weeks away from the peak of hurricane season, which is the date when statistics say we are most likely to have an active storm in the Atlantic, the Caribbean or the Gulf of Mexico.

That date, September 10th, is about a week before the most likely date for a landfall in the U.S. So we continue to watch the eastern tropical ocean.

Tropical Disturbance #1 has a slight chance of organizing a bit before it reaches the southern Caribbean islands over the weekend. But it’s most likely to arrive as a moisture surge with gusty squalls.

Aug. 28 satellite image of the tropics. (CIRA/RAMMB)

After that, the computer forecast models move it west through the Caribbean where it will have to be watched next week.

Tropical Disturbance #2 is quite large. The southern part of the disturbance is forecast to move slowly west over the next several days. Nothing is expected to happen soon, but toward the middle or end of the next week, it might be in a position to develop as it approaches the Caribbean islands.

The scenario is complicated because another disturbance will move off Africa and may interact with Tropical Disturbance #2 to one degree or the other. In any case, nothing is going to happen quickly.

Laura is still officially a tropical depression, but it is losing its tropical characteristics. It’s evolving into a typical northern low-pressure system, but it will still spread tropical moisture across the South into the Midwest. Flash flooding and tornadoes continue to be a threat.

A close-up look at Hurricane Laura’s track as it made landfall in southwestern Louisiana very early yesterday morning shows how close it was to being so much worse. The center of Laura’s circulation made a random jog to the right, passing just east of Cameron, Louisiana at about 1:00 AM CT.  That wiggle made all the difference.

Immediately to the west of Cameron, you can see Calcasieu Lake, which is part of a lake and river system that extends north to the population center of the region, Lake Charles, and beyond. Because Laura’s center went just east of there, the storm’s giant storm surge happened east of Cameron, and importantly to the east of the Calcasieu Pass, the opening from the lake to the Gulf.

If the Category 4 hurricane had jogged left or even maintained its path, that huge surge from the Gulf would have put Lake Charles under water.

A wobble like that will never be able to be forecast. It is caused by random and chaotic factors in the atmosphere and within the hurricane’s circulation. So unfortunately, we will always have situations where we forecast something extreme because the odds of it happening are high enough that people have to take action.

Specialists will go to the southern Louisiana coast to measure how high the water reached in the storm surge zone to the east of Cameron, but we know it was significant. Video shows houses swept away as the Gulf water surged over the land.

Lake Charles and the surrounding area suffered badly from Laura’s winds, of course. Recovery there will take years.

Imagine all the people living in cramped temporary quarters in the middle of a pandemic. A difficult scenario, to say the least.

We’ll keep an eye on the eastern Atlantic, but no significant threats are likely into early next week.


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