After years of predicting above-normal hurricane seasons, meteorologists are anticipating a slightly below-average 2023 Atlantic hurricane season.
But they added these important caveats: There’s still plenty of uncertainty in the forecast, and all it takes is one storm to turn a hurricane season from calm to chaotic.
Colorado State University, which has a renowned tropical weather and climate research team, is predicting 13 named storms, of which six will become hurricanes and two will reach major hurricane strength (with sustained winds of 111 miles per hour or higher). That’s according to the university’s first hurricane season forecast unveiled Thursday morning, which will be updated each month between June and August.
The call for a below-average season — and the uncertainty around that forecast — stems from two conflicting factors: the possibility for a strong El Niño, when an enhanced jet stream threatens to erode stronger hurricanes, and an “anomalously warm” Atlantic, which can fuel hurricanes.
“The tug-of-war between the hurricane-unfavorable potential of a robust El Niño and the hurricane-favorable potential of a much warmer-than-normal (Atlantic) is why the forecast is for a slightly below-average season at this point,” said Philip Klotzbach, a meteorologist at the university.
In other words: The combination of those two factors could lead to the hurricane season falling on different sides of the spectrum.
For now, though, the forecast is trending toward below-average because of an anticipated shift to El Niño for the peak season, according to the report.
The team predicts that 2023 hurricane activity will be about 80% of the average season from 1991 to 2020, meaning there will be 20% less activity than the average of those seasons.
By comparison, 2022′s hurricane activity was about 75% of the average season. But as every resident in Southwest Florida knows: A sluggish start to the hurricane season doesn’t mean it will stay slow. Last year’s season was a whisper — until Hurricane Ian came roaring along.
This outlook is just the first among many set to be released throughout the season, but it offers the first official glimpse into what 2023 has in store for us.
Here are the key takeaways from the report.
Forecasters expect El Niño this hurricane season
After three long, eventful years, La Niña dissipated earlier this year. The globe is now experiencing what’s called ENSO-neutral, meaning the period we are in is neither an El Niño or a La Niña.
La Niña typically favors more activity in the Atlantic because it removes the conditions that suppress storm formation.
It’s likely the globe will fall into El Niño conditions, but just how strong it will be is yet to be determined, according to the the outlook. There is an 82% chance of an El Niño being present at the peak of the season, Alex DesRosiers, a Colorado State University PhD candidate who helped with the forecast, wrote in an email to the Times.
A beefy El Niño could increase vertical wind shear, which is a change in high-level wind direction and strength that can tear hurricanes apart and prevent them from strengthening. El Niño typically favors more activity in the central and eastern Pacific, while it suppresses activity in the Atlantic.
“A strong El Niño is our best scenario for a quiet Atlantic Hurricane season,” DesRosiers wrote.
This year forecasters are predicting at 22% chance that a major hurricane will make landfall somewhere along the U.S. east coast — including the Florida peninsula. Forecasters put the chance of that last year at 47% while the average chance of that happening over the last century has been 31%.
Klotzbach tweeted last week that European Centre for Medium-Range Weather Forecasts (commonly known as the Euro model) is calling for a “robust” El Niño peak around October.
Still, a strong El Niño is not a guarantee for a weak hurricane season, according to Nicole Carlisle, a meteorologist for the National Weather Service’s Tampa Bay office.
She pointed to 1992, a year with a strong El Niño. That’s a year etched into the memory of many generational Floridians after a menacing Category 5 Hurricane Andrew slashed across South Florida causing dozens of deaths and an estimated $26 billion in damage.
The takeaway for residents in the Tampa Bay area?
“Don’t put too much stock into whether its El Niño or La Niña,” Carlisle said.
Warm waters in the Atlantic
The Atlantic is hot right now, and it’s complicating things.
Some areas of water in the Atlantic that churn up storm activity are running about 5 degrees warmer than normal, DesRosiers wrote.
In the ocean, the coolest water sinks to the bottom while the warmest water is at the surface. Normally, winds blow over the Atlantic that mix the warm and cold water together, but slow trade winds are causing the warm water to remain at the top of the Atlantic.
However, that doesn’t mean it will stay that way throughout the season, Klotzbach said in a phone interview with the Times.
There are a few ways this season could shake out: If the waters in the Atlantic remain warm, and there is a weak El Niño, the hurricane season could be busier. If there is a stronger El Niño and cooler water temperatures, the hurricane season will likely be calmer.
Klotzbach referenced the 2004 hurricane season, one of the most active and destructive seasons on record. That year four hurricanes reached Florida: Charley, Frances, Ivan and Jeanne.
“2004 is an example of a developing El Niño year, which wasn’t super strong, but combined with a pretty warm eastern and central Atlantic, obviously was a super busy season,” Klotzbach said.
That year El Niño kicked in around October, essentially halting any further activity.
Just a month ago, Klotzbach likely would have been forecasting a season with fewer storms, but the warm waters have given him pause.
“Given how warm the Atlantic is now relative to normal, you kind of have to respect that and not put all your eggs in the El Niño basket,” Klotzbach said.
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