Dry Air Deters Hurricanes in Mexican Caribbean

Riviera Maya, QR — As the Atlantic hurricane season reaches its peak, developing systems seem to be weakening as they approach Quintana Roo. This season, the state has only experienced one storm, Hurricane Beryl, which made landfall north of Tulum as a category 2 hurricane on July 5th. Following Beryl, the Atlantic remained calm for weeks until the National Hurricane Center (NOAA) reported another system.

Since Beryl, at least two developing systems with a predicted trajectory for the Caribbean Sea have either dissipated or slowed down as they approached tropical waters. Meteorologists suggest that an unexpected influx of dry air may be partially responsible for this calm period.

Alex DaSilva, AccuWeather's chief hurricane expert, noted an unusual amount of dry, dusty air has contributed to slowing the development of tropical storms this year. He explained, “Tropical storms and hurricanes need moisture-rich air to thrive, but those conditions have been scarce until the peak of the hurricane season. There was an unusually high amount of dry air and Saharan dust across the Atlantic during the month of August.” NASA has even captured images of large dust clouds blowing off the shores of Africa.

As time passes, the dry air is expected to decrease, creating more favorable conditions for tropical development. Alex Sosnowsk, AccuWeather’s senior meteorologist, explains that clusters of thunderstorms over Africa can become tropical waves over the Atlantic. Given the right conditions, these can evolve into tropical storms and even hurricanes. However, this year, these systems have encountered dry air over the Atlantic and struggled to develop.

Kelly Núñez Ocasio, a tropical meteorology expert and adjunct professor at Texas A&M University, concurs that dry air over the Atlantic is impeding system development. “For the first time we are seeing that this is really so,” she confirmed. “We are seeing it right now in the Atlantic hurricane season.”

Another factor contributing to the mild Atlantic hurricane season in Quintana Roo this year is the Atlantic La Niña phenomenon. While the Atlantic basin is warm, an area off the western coast of Africa is much cooler. “Research has shown that Atlantic Niñas can potentially lead to less tropical activity in the Atlantic. The reason for this cooling in the Atlantic is still not entirely clear,” she said.

Additionally, a warm upper atmosphere over the ocean can create stability that makes it difficult for merged storms to organize. “This could be related to climate change and a warmer planet," said DsSilva. However, one key factor that most meteorologists considered in their forecasts for the 2024 Atlantic hurricane season was the anticipated arrival of La Niña. Meteorologists predicted that El Niño would be replaced by La Niña around mid-season, something that has not yet happened.

La Niña is often associated with helping systems gain strength and become storms with less disruptive wind shear. On the other hand, according to the NOAA, El Niño can lead to more disruptive wind shear, which can hinder storm development.