AN EL NINO EXIT AND LA NIÑA ARRIVAL COULD WORSEN HURRICANE SEASON

a map of the world showing the major rivers
La Niña causes the jet stream to move northward and to weaken over the eastern Pacific. The south sees warmer and drier conditions than usual during La Niña. NOAA

“Expect an active hurricane season” are the usual words heard nowadays. Water temperatures are rising in the low latitudes of the Atlantic Ocean near the Equator, increasing the chances for a storm to rapidly intensify.

Even with storm-suppressing conditions from El Niño in 2023, 20 storms formed in a warm Atlantic Ocean. Seven of those became hurricanes, with three reaching strengths of a Category 3 or higher. Besides the Category 4 Hurricane Idalia, which struck North Florida in late August 2023, a majority of the storms curved away from the U.S. 

Forecasters are predicting El Niño to dissipate sooner than later, and clearing the way for La Niña to arrive mid- to late summer. La Niña, or Spanish for “little girl,” could be especially problematic during the 2024 Atlantic hurricane season. 

One of the key factors in the formation of hurricanes is vertical wind shear, or the change in wind speed and direction 5,000 to 35,000 feet above ground. Wind shear tends to weaken storm systems coming off the African coast and developing in the Atlantic. 

While an El Niño tends to keep a lid on hurricanes with wind shear, La Niña events weaken upper- and lower-level winds over the Atlantic basin and Caribbean Sea. As a result, conditions are likely favorable for more hurricane formation and intensification. 

“The earlier the La Niña pattern sets in, the less wind shear in the Atlantic and Caribbean. Tropical storms and hurricanes may find favorable conditions to form and build strength,” said Jon Rizzo, warning coordination meteorologist for the National Weather Service in Key West. 

Regardless of the signals pointing to an active hurricane season in the Atlantic, Rizzo said now is the time to begin preparations and plans should a storm threaten the Florida Keys. 

“If you are ordered to evacuate by Monroe County Emergency Management, make sure you have a plan in place to leave with your loved ones,” he said.

Jim McCarthy
Jim McCarthy is one of the many who escaped the snow and frigid temperatures in Western New York. A former crime & court reporter and city editor for two Western New York newspapers, Jim has been honing his craft since he graduated from St. Bonaventure University in 2014. In his 5-plus years in the Keys, Jim has enjoyed connecting with the community. Jim is past president of the Key Largo Sunset Rotary Club. When he's not working, he's busy chasing his son, Lucas, around the house and enjoying time with family.