Past strong El Niños, such as the one currently in place, have made it difficult to generate a tropical storm in November, the last month of the Atlantic hurricane season.
El Niño’s status: As NOAA reported in its monthly update on Nov. 9, the current El Niño has now become strong. This warming of the central and eastern Pacific Ocean near the equator is important because it can influence weather patterns around the globe, including the tropics.
A typical November: The last month of hurricane season generates one storm every 1 to 2 years, on average. November storms tend to form in the western Caribbean Sea, the southwestern Atlantic Ocean near the Bahamas or off the southeast U.S. coast, or the central Atlantic.
Squashing effect: To examine the potential influence of this El Niño, we searched NOAA’s historical hurricane database for systems that first became tropical or subtropical storms in November, then went on to become hurricanes and Category 3 or stronger hurricanes from 1950 through 2022. We did that for all El Niños, all stronger El Niños, and also for its opposite, La Niña, as well as Novembers which were neutral (neither El Niño, nor La Niña in place).
The results weren’t surprising, but still impressive as a contrast.
Only 10 systems first became storms in November during El Niños since 1950, half the number that did so in La Niña Novembers.
When we consider only Novembers with strong El Niños (at least 2.7 degree Fahrenheit temperature anomalies), only three systems became storms during the month, only one of which managed to become a hurricane, Kate in 2015.
What those past November El Niño tracks looked like: The map below shows the tracks of the 10 El Niño November storms in the first image, followed by the lonely three stronger El Niño November tracks.
Note the lack of activity in the western Caribbean Sea or Gulf of Mexico, particularly for the stronger El Niño Novembers.
According to NOAA’s database, 1994’s Gordon was the only storm to have made landfall in the U.S. during an El Niño November, doing so in Florida as a tropical storm. Hurricane Ida approached the northern Gulf Coast in November 2009, but then fizzled before moving ashore, though it would later help spin up a destructive East Coast storm.
Why the El Niño squashing: The typical effect of a stronger El Niño is to boost shearing, westerly winds aloft over the Caribbean Sea and parts of the Gulf of Mexico that’s hostile to any system trying to develop.
That’s in addition to a sharp increase in wind shear near the mainland U.S. as the colder months settle in.
Stronger El Niños can also produce sinking air over parts of the Caribbean Sea, suppressing the thunderstorms that are building blocks of tropical storms.
The disclaimers: As financial planners often say, past returns don’t guarantee future results.
In this case, every El Niño, and its effect on the atmosphere, is different. And El Niño isn’t the only influence on the weather pattern.
Three storms did manage to form in past Novembers during strong El Niños.
But if past history is an indication, it’s an uphill battle to generate one this time of year in these conditions.
Dracul 1 Bran District 
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