Isn’t the Caribbean still affected by a dying tropical wave? As the Atlantic hurricane season is going to be the busiest in September, there is still one system Invest 91L that tells us that a mess may result even from a faltering storm. A thunderstorm cluster more than 1,000 miles east of the Windward Islands is basically a rundown of the way from Africa to the Lesser Antilles. Its chances of becoming Tropical Storm Gabrielle have been lowered to almost zero but the area of the system could be giving that the islands may receive some impacts around the middle or the end of the next week, as per the meteorologists.
The downgrade of the system’s development potential is basically due to the fact that it has met with regions of dry, stable air in the eastern Atlantic, which is turning out to be its main adversary. Dry air is very unfriendly to the development of thunderstorms, which in turn provide energy to further development of the system, thus in this case the Saharan Air Layer may be involved. Jason Dunion of NOAA, among others, has stated that the Saharan Air Layer is “a huge dust storm that can be the size of the continental United States,” carrying super-dry air, mid-level easterly jets, and dust particles that suppress convection and eventually may lead to the tearing apart of the storms that are in their developing stage. Small-scale systems like Invest 91L are extremely vulnerable when they find themselves in such conditions.
Wind shear can be considered another strong enemy. Vertical wind shear (changes in wind speed and direction at different altitudes) can tilt and break a storm’s vortex, which is the source of the storm’s heat and moisture, thus the storm will be weakened. As Bill Gray, in his groundbreaking research, said, “Large vertical wind shears do not allow for area concentration of the tropospheric distributed cumulonimbus condensation.” Even with the help of moderate local wind shear, dry air, and other factors in the environment, the investing 91L experiment has had its development potential lowered considerably according to the recent advisories from the National Hurricane Center, which has been quoting its seven-day formation chance to almost zero.
The inactivity that is currently being observed here is atypical of mid-September, which is historically regarded as the most active period of the season. The question of when most of the seasonal activity occurs is answered by the National Hurricane Center, which points out that approximately 70% of the total number of events are to be expected from September onward . In reality, things are going to get even better toward the end of this month when wind shear is going to be at its lowest, and the region will be filled with moist and unstable air. Colorado State University forecast team is also on the same page signaling that the tropics can be more alive in the weeks to come with multiple tropical waves departing off Africa and moving into the warmer waters.
Quiet times should not be perceived as a break by inhabitants living along the coasts of the Caribbean and the Atlantic seaboard but rather as an opportunity to beef up the defenses. “It only takes one storm to make it an impactful year for your community,” says the National Hurricane Center. Get ready today because this can make a big difference later. If you still wonder what the well-prepared hurricane kit should look like, a brief list of the essentials can be comprised of water, long-lasting food stuffs, medicines, flashlights, batteries, chargers, and copies of insurance policies. Properness of your shelter the installation of the permanent or temporary storm shutters or the cleaning of drainage system are measures that help to alleviate storm impacts if a hurricane is going to strike your area.
It is just as important to keep up with the news. Being up to date with the latest from the NHC, your local meteorological agencies, and reliable weather apps is a must if you want to be the first to know of any changes of conditions or a storm’s track. Residents of coastal areas can only benefit from evacuation orders if they follow them promptly and if they have prior knowledge about where emergency shelters are located.
Perhaps without ever being given a name, Invest 91L might eventually disappear, but its trek highlights how thin the line is between various atmospheric factors and their ability to decide the fate of a tropical wave. As it stands, dry air, wind shear, and dust can hinder the development of storms, but once those obstacles disappear, it is the same wave patterns that can lead to rapid intensification. The main reassurance for people living in hurricane-prone regions is that they still have the option to remain vigilant which is the best way of ensuring their safety throughout a season when most of the storms are yet to come.
