I actually try to avoid headlines like this one. At times, weather and climate information can be presented in a hyperbolic way. As a scientist, my goal is to convey objective facts with appropriate context based on my training and experience. With that being said, I am very concerned about ominous signals several months in advance of the 2024 hurricane season.
Anomalously Warm Sea Surface Temperatures
The first signal is ocean temperatures. The North Atlantic was running warm in 2023, and continues to be alarmingly warm in 2024. WFLA Chief Meteorologist Jeff Berardelli wrote on the NewsChannel 8 website, “Meteorologists like myself were astonished by last year’s unprecedented sea surface temperatures in the North Atlantic. And yet, to our amazement, they are even more deviant right now, especially in the main hurricane development region of the Tropical Atlantic.” I generated a map using the University of Maine Climate Reanalyzer tool (above) to illustrate the anomalously warm conditions as of late February.
Brian McNoldy is a hurricane expert at the University of Miami. He posted on the platform X that we are witnessing something unprecedented from our perspectives. The North Atlantic sea surface temperatures are far beyond typical climate normal ranges.
Warm waters are the “fuel supply” for hurricanes. It is only February so it would be irresponsible to draw firm connections between temperatures in the North Atlantic right now and those several months later. However, Berardelli points out in his blog, “Well, it is definitely too early to know with great certainty, partially because the water temperatures may moderate before the season, but warm February sea surface temperatures do often correlate with active hurricane seasons.”
The 2023 Atlantic hurricane season ranked fourth for most-named storms in a year since 1950. According to a National Oceanic and Atmospheric Administration press release, “The Atlantic basin produced the most named storms of any El Niño influenced year in the modern record.” Matthew Rosencrans is lead hurricane forecaster at NOAA’s Climate Prediction Center. He said, “The record-warm ocean temperatures in the Atlantic provided a strong counterbalance to the traditional El Niño impacts.” On average, El Niño suppresses Atlantic hurricane activity due to increased wind shear, trade winds, and less favorable conditions for air to rise. This brings me to the other point that concerns me about 2024.
Is La Niña Coming?
Most climate experts and models are projecting a transition from El Niño conditions and a possible onset of La Niña conditions. In early February 2024, a report from the NOAA Climate Prediction Center stated, “In summary, a transition from El Niño to ENSO-neutral is likely by April-June 2024 (79% chance), with increasing odds of La Niña developing in June-August 2024 (55% chance).” Atlantic hurricane activity has been associated with increased activity during La Niña.
If 2023 produced twenty named storms (seven hurricanes, three major) in less favorable El Niño conditions, it is reasonable to be on heightened alert for the 2024 season given the possible combination of La Niña and abnormally warm ocean temperatures. Will the sea surface temperatures remain this warm? Will La Niña actually happen? Only time will tell, but both scenarios seem probable.
And by the way, I should probably mention that we have already seen a tropical storm (Akará) form in the South Atlantic Ocean. Tropical storms rarely form off the coast off Brazil. Warm seas are likely the culprit there too.