September’s significant hurricanes

 

Hurricane Helene, September 2024 (Source: NOAA)

Although it may not seem like it this season, September is statistically the busiest month of the Atlantic hurricane season. Whenever a tropical storm or hurricane is particularly destructive or deadly, the World Meteorological Organization retires its name. There are four September hurricanes that have impacted the United States in the last decade that have had their names retired.

Hurricane Helene (2024): Helene developed in the western Caribbean Sea and intensified into a major hurricane as it tracked northward into the Gulf. It reached its peak intensity as a Category 4 hurricane with sustained winds of 140 mph and a minimum central air pressure of 939 millibars (mb). By comparison, standard sea level air pressure is approximately 1013 mb. Helene made landfall in northwestern Florida near the town of Perry and was a prolific rainmaker in areas well inland. Widespread flooding occurred from the remnants of Helene as far north as the Carolina’s and Tennessee Valley. According to NOAA, the storm is responsible for approximately 250 deaths in the United States along with $78.7 billion in damages (2024 dollars).

Hurricane Ian (2022): Ian developed in the Caribbean Sea and was upgraded to hurricane status south of Cuba. It intensified rapidly after crossed Cuba as it headed toward southwestern Florida. Ian briefly reached Category 5 intensity (160 mph / 937 mb), but made landfall as a Category 4 hurricane on Cayo Costa Island in southwestern Florida. Ian was an exceptionally destructive storm and did an estimated $119.6 billion in damages (2024 dollars). That not only made it the most destructive hurricane in Florida state history (ahead of other catastrophic storms like Irma, Charley and Andrew), but Ian remains the third costliest hurricane overall in the United States.

Hurricane Florence (2018): A long lasting Cape Verde hurricane that lasted more than two weeks, Florence was a Category 4 at peak intensity over the open Atlantic. It had sustained winds of 150 mph and a minimum central air pressure of 937 mb. Fortunately, it weakened to Category 1 intensity before its landfall in North Carolina on September 14. However, because the atmospheric steering currents were very weak, it meandered across the Carolinas and Mid-Atlantic Region for several days where devastating flooding resulted. According to NOAA, Florence did an estimated $30.0 billion in damages in the United States (2024 dollars).

Hurricane Irma (2017): Irma was another long-lasting Cape Verde hurricane that reached Category 5 intensity on two separate occasions. At peak intensity, Irma had sustained winds of 180 mph and a minimum central air pressure of 914 millibars (mb). Irma left a deadly trail of destruction across much of the Caribbean and ultimately made landfall in Florida as a Category 4 hurricane. It was the first Category 4 hurricane to make landfall in Florida since Charley in 2004. Ultimately, Irma killed dozens in the United States and did $64.0 billion in damages (2024 dollars).