The probability of tropical development of the Caribbean system is increasing and is expected to move into the Gulf

MIAMI – As tropical activity in the Atlantic calms down, attention is turning back to the Caribbean and Gulf of Mexico, where there are increasing signs that atmospheric conditions may favor the development of the next named storm sometime next week.

The National Hurricane Center is now officially monitoring the area for tropical development. The agency currently estimates medium chances for development within the next seven days. According to the FOX Forecast Center, the development may worsen even after seven days.

The growing concern is related to a phenomenon known as the Central American Gyre, which in the past has contributed to the formation of tropical storms in the Caribbean or Gulf of Mexico in early spring or fall.

Central American vortex.

(FOX Weather)

The vortex is a broad low-pressure system fed by moisture flowing in from the Pacific Ocean that forms near or over Central America. At its core, it is a powerful rain producer whose effects extend for hundreds of miles, threatening torrential rain, flooding and landslides in more than a dozen countries in and around Central America.

WHAT IS THE CENTRAL AMERICAN VORTEX?

Organized low-pressure systems can form within the large gyre if water temperatures and upper-level winds favor tropical development. And current water temperatures in the Caribbean are close to last season's record levels.

Sea surface temperatures in the Caribbean.

(FOX Weather)

At both the beginning and end of the hurricane season, it is more common for a tropical disturbance to break away from Central America and form a tropical unit in either the eastern Pacific, the Bay of Campeche, or the western Caribbean Sea.

Potential development area in the next 10 days.

(FOX Weather)

“There may be showers and storms, and some of the energy may come from that, break off and transform into something that may develop from the Gulf of Mexico or the Caribbean,” said FOX Weather meteorologist Marissa Torres.

In fact, many computer model predictions predict that large amounts of moisture from the Pacific Ocean will flow across Central America and enter the Caribbean Sea sometime next week, where they may form a vortex.

Meanwhile, early indications are that an upper-atmosphere deepening of the jet stream over the central U.S. will move northward, removing a blockage that would prevent storms from entering the Gulf of Mexico and allowing the vortex to drift northward into the southern Gulf of Mexico.

The possible weather pattern that will prevail over Central America, the Caribbean and the Gulf of Mexico next week.

(FOX Weather)

“So if we see that broad circulation and maybe it moves into the southern Gulf of Mexico or at least swings a little bit further north, then that opens a window for possible (tropical) development,” said Stephen Morgan, a meteorologist with FOX Weather. “And assuming we don't have any significant systems moving off land into the Gulf of Mexico — particularly fronts that would steer the thing away — there will be some Gulf of Mexico element in play.”

While storm development is never guaranteed, the pattern suggests an active period of rain in the Caribbean, parts of Mexico, and likely southern Florida through the end of next week, according to the FOX Forecast Center. Regardless of if or when individual storms undergo tropical development, there will be a large plume of tropical moisture in the region through the end of next week that will likely persist.

Long-range precipitation forecast for the Caribbean.

(FOX Weather)

“When you look at the Bay of Campeche, you look at the water temperatures – there are a lot of other elements that are still conducive to development,” said Michael Estime, meteorologist with FOX Weather. “We'll have to watch what happens with the Eyre … something we'll certainly be watching in the coming days.”

How often does the vortex cause tropical problems?

On average, a tropical cyclone occurs in the Central American Gyre about every two years. Under the right conditions, some cyclones develop into full-blown hurricanes.

Due to the formation of hotspots in the Caribbean or regions in the southern Gulf of Mexico, many of them also threaten the southeast coast.

Tropical Storm Amanda (2020), Tropical Storm Cristobal (2020), Hurricane Michael (2018), Tropical Storm Andrea (2013), and Hurricane Ida (2009) are all examples of areas of unsettled weather that formed away from the Central American Gyre.

Tropical cyclones influenced by Central American gyres.

(FOX Weather)

Hurricane Michael struck the Florida Panhandle as a Category 5 hurricane in 2018 after spending a week in the large vortex off the coast of Central America.

Because they form early or late in the season, tropical cyclones directly influenced by the Central American cyclone tend to have a weaker impact on the United States because of inhibiting factors such as cooler water temperatures and hostile high-altitude winds.