El Niño can impact November into hurricane season
- There is a strong El Niño in place.
- The past strong El Niño had an overwhelming impact on the hurricane season last month.
- This is due to several factors resulting from the stronger El Niño phenomenon.
Previous strong El Niños, like the one we have now, have made it difficult to generate a tropical storm in November, the last month of the Atlantic hurricane season.
El Niño status: As the National Oceanic and Atmospheric Administration (NOAA) reported in its monthly update on November 9, the current El Niño is now strong. This warming in the central and eastern Pacific Ocean near the equator is important because it can affect weather patterns around the world, including the tropics.
Typical November: The last month of hurricane season generates one storm every one to two years on average. November storms tend to form in the western Caribbean Sea, the southwestern Atlantic Ocean near the Bahamas or off the southeastern coast of the United States, or the mid-Atlantic Ocean.
(Enhance your forecasts with our hour-by-hour breakdown for the next eight days – available only on our website.) Premium Pro experience.)
Past tropical development zones in November.
(Data: NOAA/NHC)
Crushing effect: To study the potential impact of this El Niño, we searched the National Oceanic and Atmospheric Administration’s (NOAA) Historical Hurricane Database for systems that initially became tropical or subtropical storms in November, then developed into hurricanes and Category 3 or stronger hurricanes from 1950 through 2022. We did it for everyone. El Niño, all stronger than El Niño, and also its opposite, La Niña, as well as the months of November that were neutral (neither El Niño nor La Niña were in place).
The results were not surprising, but they are still impressive in contrast.
Only 10 systems became storms for the first November El Niño since 1950, half the number that did so in a La Niña November.
When we consider only November months that experience strong El Niño (at least 2.7°F temperature anomaly), only three systems became storms during the month, of which only one managed to become a hurricane, Kate in 2015.
As a senior meteorologist Chris Dolce Discussed in a previous article, El Niño typically deflects the last storm of the hurricane season earlier.
Number of systems that initially became tropical or subtropical storms in November, then became hurricanes, then Category 3 or stronger hurricanes in all El Niño Novembers (yellow bars), stronger El Niño Novembers (red bars), and stronger El Niño Novembers (red bars). La Niña (blue bars; bars) and November without El Niño or La Niña (neutral bars; gray bars) from 1950 to 2022.
(Data: NOAA; Bar graph: Infogram)
What El Niño tracks looked like last November: The map below shows the tracks of the 10 El Niño storms for November in the first image, followed by the tracks of the three strongest El Niño storms for November.
Note the lack of activity in the western Caribbean Sea or Gulf of Mexico, especially in the stronger El Niño months of November.
According to NOAA database, Hurricane Gordon of 1994 was the only storm to make landfall in the United States during an El Niño event in NovemberTo do this in Florida as a tropical storm. Hurricane Ida approached the northern Gulf Coast in November 2009, but then dissipated before moving ashore, although it would later help unleash a devastating storm surge on the East Coast.
(First image) The 10 tracks of systems that first became tropical or subtropical storms in November during an El Niño from 1950 to 2022. (Second image) The three tracks of systems that did so in November during the strongest El Niño since 1950.
Why El Niño crushes: The typical effect of a stronger El Niño is enhanced shear and high westerly winds over the Caribbean Sea and parts of the Gulf of Mexico that are hostile to any system that attempts to develop.
This is in addition to the sharp increase in wind shear near the mainland United States with the arrival of the colder months.
A stronger El Niño can also produce sinking air over parts of the Caribbean Sea, suppressing thunderstorms that are the building blocks of tropical storms.
Current wind shear, satellite image
(Areas of clouds are shown in white. Areas of strong wind shear, the difference in wind speed and direction with height, are shown in purple. High wind shear is hostile to mature tropical cyclones and those trying to develop.)
Evacuation responsibilaty: As financial planners often say, past returns do not guarantee future results.
In this case, each case of El Niño and its effect on the atmosphere is different. The El Niño phenomenon is not the only influence on weather patterns.
Three storms managed to form last November during a strong El Niño event.
But if past history is any indication, it’s an uphill battle to breed one at this time of year in these conditions.
More at Weather.COM
– How could the 2023 Atlantic hurricane season go higher?
– 6 changes that the stronger El Niño phenomenon may bring about this winter
– Snowfall and El Nino phenomenon
– How did the El Niño phenomenon get its name?
Jonathan Erdmann is a senior meteorologist at Weather.com and has been covering national and international weather since 1996. His lifelong love of meteorology began with a close encounter with a tornado as a child in Wisconsin. He studied physics at the University of Wisconsin-Madison, then completed a master’s degree working with dual polarization radar and lightning data at Colorado State University. Extreme and strange weather are his favorite subjects. Contact him on X (formerly Twitter), Threads And Facebook.
The Weather Company’s primary journalistic mission is to report on breaking weather news, the environment, and the importance of science in our lives. This story does not necessarily represent the position of our parent company, IBM.
