Maria is quickly exiting the stage. The system that just last week was the most dangerous weather phenomenon on the planet has weakened to a tropical storm and is now heading east, away from the United States. It is forecast to become a nontropical storm over the North Atlantic this weekend. Hurricane Lee has also weakened to a Category 2 and will suffer the same fate as Maria.
Both Lee and Maria formed from disturbances that came from Africa in early to mid-September. The “Cabo Verde season,” as it’s referred to, typically lasts from mid-August through early October. After that, persistent hostile vertical wind shear sets up over the eastern Atlantic and squashes the chances that any of the storms will develop.
But to the west, the Caribbean Sea and Gulf of Mexico usually become hotbeds for hurricane development in the fall — and that’s exactly what we’re seeing now.
As long as there are thunderstorms and plenty of warm water in the tropics, hurricanes have the potential to form, which is why the season lasts through the end of November. In fact, October has proved to be just as destructive as August or September.
You may recall some infamous October storms — Sandy in 2012, Wilma in 2005, Iris in 2001, Mitch in 1998, Hattie in 1961 and Hazel in 1954.
Particularly concerning this year is the exceptionally warm water in the Caribbean, where autumn storms tend to form. Any storms that develop there have the potential to be extremely intense.
“We are seeing some of the hottest ocean temperatures on the planet in the western Caribbean Sea,” Michael Ventrice, a research meteorologist at the Weather Company, told The Washington Post last week. “This is like rocket fuel for developing tropical cyclones. A major concern for late-season development.”
As if on cue, there’s a cluster of thunderstorms and strong winds brewing in the Caribbean near Cuba right now. The National Hurricane Center is giving the disturbance a 40 percent chance of formation within the next five days. Its likely path is north toward Florida.
Models generally keep this disturbance disorganized as it heads north, probably along the east coast of the Florida peninsula this weekend. So it might not be a big wind maker, but it will dump heavy rain over western Cuba and south Florida from Friday through Monday.
Beyond the weekend, the European and U.S. long-range models are hinting at a possible development in the southwestern Caribbean and then a track toward the north, which would bring the system toward the Yucatan and Cuba in about 10 days. It is way too early to speculate about intensity or exact track yet.
The next name on this year’s list is Nate, a name that is still around from its first time on a list in 1981. It was used in 2005 and in 2011, but has not yet been retired.