Ask an Expert: A Review of the 2023 Atlantic Hurricane Season

The 2023 Atlantic hurricane season came to a close on November 30. According to Dr. Brian Colle, the CHEER Hub’s hazards thrust leader and an Atmospheric Science Professor at Stony Brook University, these are four facts that made this past season worth noting. 

Stony Brook, NY; Stony Brook University: Brian Colle, Professor, Director for Institute for Terrestrial and Planetary Atmospheres (ITPA) and leader of the Coastal Meteorology and Atmospheric Prediction Group (COMAP) in SoMAS in front of a satellite image of Hurricane Sandy.

The 2023 Atlantic hurricane season ranks fourth for the most named storms in a year since 1950. 

The 2023 Atlantic hurricane season is not easily characterized using broad strokes. According to the National Oceanic and Atmospheric Administration (NOAA), the Atlantic basin saw 20 named storms during the 2023 hurricane season. Of these storms, seven were hurricanes and three intensified to major hurricanes. For reference, an average season has 14 named storms, seven hurricanes, and three major hurricanes.This season’s activity fell within the NOAA’s Climate Prediction Center’s forecasted ranges for named storms and hurricanes in the updated outlook it issued in August.

Recording-breaking ocean temperatures and a strong El Niño gave way to an above-normal hurricane season.

The above-average number of storms was somewhat surprising since this is an El Niño year. In a recent NOAA press release, the Climate Prediction Center’s Matthew Rosencrans said the Atlantic basin “produced the most named storms of any El Niño-influenced year in the modern record.” Research has shown that El Niño, a natural climate pattern characterized by warmer ocean temperatures in the equatorial Pacific that occurs every 2-7 years, typically favors less Atlantic hurricane development because of increased winds aloft that prevent storms from organizing. However, this weather phenomenon may have been largely offset by record-warm ocean temperatures in the Atlantic. Dr. Colle noted that “although an El Nino year typically favors less Atlantic hurricane activity this year illustrates that we can still get above average number of storms, which can intensify and impact the East and Gulf coasts.” 

Idalia was the only Atlantic storm that made landfall in the U.S.

Despite the above-average number of named storms, most of the U.S. Eastern seaboard was spared. Hurricane Idalia was one of only two hurricanes that made landfall this season when it struck Florida’s Big Bend region in August. According to the National Weather Service, Idalia was the first major hurricane on record to make landfall in this region. Further, the storm’s seven- to 12-foot surge rivaled and – in some areas – exceeded values observed in 1993’s “Storm of the Century.”

According to Dr. Colle most of the storms this season were steered to the northeast away from the. U.S. East Coast as a result of a persistent trough of low pressure near the coast.

Caption: The tracks and intensity (colored lines) of the 20 named tropical storms and hurricanes over the Atlantic basin during the 2023 season. (Image credit: NOAA)

The number of storms that underwent “extreme rapid intensification” was above average.

This past hurricane season featured one of the most rapidly intensifying storms on record. The National Hurricane Center calls this phenomenon rapid intensification, which is an increase in peak winds of at least 35 m.p.h. in 24 hours or less. September’s Hurricane Lee went beyond normal rapid intensification when peak wind speeds climbed an additional 80 m.p.h per hour in less than 24 hours to become a Category 5 hurricane. Hurricane Lee is one of only six storms to undergo this rate of intensification over the Atlantic basin. Dr. Colle noted that this rapid intensification occurred over the anomalously warm waters over the Atlantic that were around 87F (30.5C).