2024 Atlantic Hurricane Season: ‘Hyperactive’ Season With 3 Hurricanes Making Landfall in Florida

As the 2024 Atlantic hurricane season wraps up on Saturday, it will indeed go down in the books as a “hyperactive” season that, despite not quite reaching the lofty forecasts for record activity given in the spring, still reached levels well above average. , according to researchers at Colorado State University (CSU).

The “hyperactive” designation comes from the seasonal Cumulative Cyclone Energy (ACE) ratio—a measurement that takes into account the strength and length of time that tropical storms and/or hurricanes are active in the basin.

The 2024 season ended with an ACE value of 162 – above the “hyperactive” threshold of 159.6 and 23% above average, but still below CSU’s original forecast of 210, which was raised to 230 later in the season.

CSU forecasters also predicted 23 named storms this season, with a brief increase in the forecast to 25 named storms in their July 9 update. Instead, the season saw 18 named storms, which was below the forecast but still above the average of 14-15.

“Our April and June seasonal forecasts performed best for all metrics,” wrote Dr. Phil Klotzbach and his team at CSU. “The slight increase in overall activity that we predicted with our July and August updates did not materialize. We characterize our 2024 forecast as a modest over-forecast of overall activity.”

CSU predicted 11-12 hurricanes this season, equal to 11 observed.

An unexpected mid-season break affected the accuracy of seasonal forecasts

Multiple factors at play led to the aggressive forecast. Water temperatures in the Atlantic, Caribbean and Gulf of Mexico were at or near record temperatures. Wind shear was weak, falling to the lowest levels recorded between August and October, CSU said.

The leading and trailing edges of the season have been very active, with Hurricane Beryl setting records for the earliest Category 5 storm on record and 10 named storms between September 9 and October 31 – with three more in November. Leslie, Milton and Kirk became the first time a trio of hurricanes have been active in the Atlantic Basin since September, according to NOAA. Seven hurricanes formed since September 25 was also a record.

But an unexpected break of several weeks came from the end of August to the end of September, which is usually among the most active times of the season. Klotzbach and his team attributed the quietness to a combination of factors. These include a northward shift of storm tracks coming from Africa that put the systems in drier air, an abnormally warm upper atmosphere and too much wind shear in the heart of the Atlantic. The gap between newly named storms from August 13 to September 8 was the first since 1968.

The lull resulted in the season totals being less than forecast. But even with fewer storms, it was still a strong season.

Five hurricanes made landfall on US shores, including Beryl, Debby, Francine, Helene and Milton.

The last two alone reached Florida within two weeks and caused widespread devastation across the state and the Southeast, killing more than 250 people and causing an estimated $200 billion in damage.

Still plenty of unprecedented tropical activity

Despite the number of tropical cyclones falling short of seasonal forecasts, CSU says there were a number of events and observations that set this season well above a typical hurricane season:

• The 11 hurricanes in the Atlantic basin tied for fifth most hurricanes in a season.
• Five hurricanes making landfall in the US tied 1893, 2004 and 2005 for the second-most US landfalls in a season, behind the six in 1886, 1985 and 2020.
• Four major hurricanes have formed in the Atlantic since September 26 – the second-most in that period, behind the five that formed in 2020.

• The 162 ACEs in 2024 is the 11th “hyperactive” season since the start of the satellite era in 1966. The 100 ACEs produced on September 24th were the second most generated since then, just behind the 109 ACEs in 1878.
• Hurricanes Kirk and Leslie set records for the most easterly formation of a hurricane in October.
• Hurricane Beryl set records for the earliest Category 5 storm, fastest intensification before July (63 mph in 24 hours), and peak wind speed of 165 mph was the strongest hurricane before August.
• Hurricane Milton’s maximum sustained winds of 180 mph were the strongest in the Gulf of Mexico since Hurricane Rita in 2005, and its minimum central pressure of 897 mb was the lowest for a hurricane since Wilma in 2005.
• Hurricane Rafael was only the second time a major hurricane formed in the Gulf of Mexico in November, besides Kate in 1985.