US Gulf Coast put on alert for potential tropical threat
AccuWeather meteorologists have given the disturbance in the Gulf a high risk of development. The next name on the list of tropical storms for the 2021 Atlantic hurricane season is Claudette.
AccuWeather Global Weather Center – June 15, 2021 – Monday marked the two-week point in the Atlantic hurricane season, and the basin was brimming with activity. As the second named storm of the 2021 Atlantic hurricane season developed off the Eastern Seaboard Monday night, AccuWeather meteorologists continued to warn of the potential for development in the southwestern Gulf of Mexico later this week.
Whether a named tropical system develops in the Gulf or not, AccuWeather forecasters caution that tropical moisture is predicted to arrive in parts of the southern United States that have been dealing with torrential rain and flooding since May, potentially making matters much worse for hard-hit communities.
AccuWeather meteorologists have given the disturbance in the Gulf a high risk of development. The next name on the list of tropical storms for the 2021 Atlantic hurricane season is Claudette.
Clouds, showers and thunderstorms have been forming and dissipating over the southwestern Gulf of Mexico since late last week. Thus far, wind shear, dry air and proximity to land have been keeping tropical system formation at bay. These inhibiting factors are likely to continue through midweek.
However, a tropical disturbance churning over the eastern Caribbean Sea Monday is projected to drift toward the region around Thursday and could help to provide a spark to initiate tropical development.
If something does form in the western Gulf of Mexico, odds favor it not becoming very strong, AccuWeather Hurricane Expert Dan Kottlowski said.
"Wind shear north of the feature is expected to be rather high later this week so any attempt to move northward will cause the tops of the thunderstorms to be blown off to the northeast," Kottlowski stated.
Wind shear is the change in the strength or direction of breezes with increasing altitude or over a horizontal area above the Earth's surface.
When wind shear is high or increases relative to a storm's movement, it can cause the system to lean, like a poorly rooted tree. This leaning effect can also affect the circular shape of the moisture associated with the storm and can inhibit strengthening.
"Wind shear is likely to be a constant negative impact on development as the system tries to move northward later this week," Kottlowski explained.
Such a system may become no stronger than a tropical storm, but a powerful hurricane is not needed to produce torrential rainfall and major flooding.
"Flooding remains the main concern with this feature in the Gulf," warned Kottlowski, adding that will be the case no matter how strong the system becomes, especially as it moves northward toward the southern U.S.
Because of the likelihood of significant southwesterly wind shear as this feature moves northward, a sweep of dry air may keep the bulk of the rain away from much of the Texas coast, except for areas northeast of Galveston Bay.
This may also focus the plume of tropical downpours on Louisiana, Mississippi, Alabama and the Florida Panhandle beginning as early as Friday and perhaps lasting into early next week.
However, exactly how much rain falls and where may depend on the exact track and intensity of the system. A moderate tropical storm may focus heavy rain in a more concentrated area, whereas a poorly organized feature is likely to spread out rain over a wider area with lower precipitation accumulation in any one area.
A track into Louisiana or southern Mississippi may focus more rain along the central and northeastern Gulf Coast. On the other hand, a tropical storm tracking toward the Texas and Louisiana border might trigger heavier rain as far west as the upper Texas coast and especially across southwestern Louisiana.