The Atlantic basin could see a below-average hurricane season due to developing summer weather patterns.
The Colorado State Tropical Meteorology Project team is predicting 13 named storms during the Atlantic hurricane season, which runs through Nov. 30. Of those, researchers expect six to become hurricanes and two to reach major hurricane strength (Saffir/Simpson Category 3 or higher) with sustained winds of more than 110 miles per hour.
The hurricane researchers are predicting a slightly below-average Atlantic hurricane season in 2023, citing the likely development of El Niño conditions in the months of August and September — the peak of the season — as a primary factor. However, there is uncertainty as to how strong El Niño would be if it does develop, university officials said. El Niño tends to increase upper-level westerly winds across the Caribbean into the tropical Atlantic.
“The increased upper-level winds result in vertical wind shear which can tear apart hurricanes as they try to form,” according to a university press release.
When waters in the eastern and central tropical and subtropical Atlantic are warmer than normal, university researches said it tends to force a weaker subtropical high and associated weaker winds blowing across the tropical Atlantic. However, given the conflicting signals between a potentially strong El Niño and an anomalously warm tropical and subtropical Atlantic, the CSU team stressed that there is more uncertainty than normal with this outlook.
So far, the 2023 hurricane season is exhibiting characteristics similar to 1969, 2002, 2004 — which brought Charley, Frances and Jeanne to our area — 2006, 2009, 2012, 2014 and 2015.
“Our analog seasons exhibited a wide range of outcomes, from below-normal seasons to hyperactive seasons,” said Phil Klotzbach, research scientist in the CSU Department of Atmospheric Science and lead author of the report. “This highlights the large uncertainty that exists with this outlook.”
The team predicted that 2023 hurricane activity will be about 80 percent of the average season from 1991–2020. By comparison, 2022’s hurricane activity was about 75 percent of the average season. But, the researchers cautioned residents to take their annual proper precautions despite any forecast.
“It takes only one storm near you to make this an active season for you,” said Michael Bell, professor in the CSU Department of Atmospheric Science.
The CSU team will issue new forecast updates on July 6 and Aug. 3.
The report also includes the probability of at least one major hurricane making landfall, which are in line with the averages from 1880-2020. It’s 44 percent this year for the entire U.S. coastline (the long term average is 43 percent), 22 percent for the U.S. East Coast including the Florida peninsula (average is 21 percent), 28 percent for the Gulf Coast from the Florida panhandle westward to Brownsville (average is 27 percent) and 49 percent for the Caribbean (average is 47 percent).
This is the 40th year that the CSU hurricane research team has issued an Atlantic basin seasonal hurricane forecast. Bill Gray, who originated the seasonal forecasts, launched the report in 1984 and continued to author them until his death in 2016.
