2023 Atlantic Hurricane Season Recap

The 2023 Atlantic hurricane season, which officially ended on Thursday, November 30th, featured above-normal tropical activity, record-warm sea surface temperatures, and a strong El Niño.

Leading into the hurricane season, AEM forecasters noted the two most important competing factors were the record-warm ocean temperatures in the Atlantic and the emergence of El Niño. When El Niño didn’t quite take over as much as expected, the very warm ocean temperatures across the Atlantic won out and counteracted the typical effects of El Niño. This facilitated an above-average hurricane season, despite the El Niño year.

There were 20 named storms in 2023, which ranks fourth for the most-named storms in a year since 1950. Seven storms became hurricanes and three intensified to major hurricanes. The 30-year averages are 14 named storms, 7 hurricanes and 3 major hurricanes.

Although there was a high number of storms, Hurricane Idalia was the only U.S. landfalling hurricane in 2023. Idalia made landfall near Keaton Beach, Fla., as a strong Category 3 hurricane with winds of 125 mph. This was the strongest hurricane to hit the Big Bend region in more than 125 years.

Idalia generated a destructive storm surge of 7 to 12 feet and delivered widespread rainfall leading to flooding in Florida and throughout the Southeast. Idalia killed four people in Florida, and while Idalia made landfall in one of the least populated areas of Florida, damage is estimated around $2.5 billion.

While warm sea-surface temperatures contributed to a higher number of storms this year, the lack of landfalling storms in the United States is mostly attributed to a weaker than normal Bermuda High. Since the Bermuda high was regularly weak, most storms were steered north before they reached the U.S. In addition, increased wind shear from El Niño inhibited systems from developing in the Caribbean and then affecting the United States.

The consistently weak Bermuda High also fostered slower trade winds across the development region of the Atlantic between the Lesser Antilles and Africa. Lighter winds led to calmer oceans, and warmer sea-surface temperatures, which helped provide more favorable conditions for storm development.

Weaker trade winds extended all the way to Africa, which resulted in less Saharan dust intrusions pushing across the Atlantic. The warmth, dryness, and strong winds associated with Saharan air suppress tropical cyclone formation and intensification. When there is less dry Saharan air, as was the case this season, there is more heat and moisture present, supplying fuel for storms.

Latest ENSO projections indicate El Niño will persist this winter then steadily weaken during the spring of 2024. By the time the next hurricane season rolls around on June 1, 2024, a weak El Niño or neutral ENSO state will be possible. AEM will issue its 2024 hurricane seasonal outlook in May 2024.

Story Image: NOAA's GOES-16 satellite showing Hurricane Idalia approaching the western coast of Florida while Hurricane Franklin passed across the Atlantic Ocean on August 29, 2023. (Image credit: NOAA Satellites )