For the first time in over 30 years, we are seeing evidence that the Atlantic Multidecadal Oscillation (AMO) might be heading into its negative (cool) phase. If this shift is real, it could fundamentally change our weather patterns for the next two decades.
See Is the Atlantic Shifting Gears? - Fred Pickhardt's Substack
The ECMWF has lots on AMOC (Atlantic Meridional Overturning Current) that Fred mentions in his AMO (Atlantic Multi Decadal Oscillation) piece …
(ecmwf.int/search/site?search_api_fulltext=amoc).
… but this recent bit on El Niño/ENSO covers the phenomenon most likely to trigger that AMOC shift - scary!
How confident should we be in a prediction of El Niño? | ECMWF
For more reinforcement & background, see the following monthlies from Copernicus…
Sea surface temperatures approach record levels in March | Copernicus
Surface air temperature for March 2026 | Copernicus
.. or amuse yourself with the daily pulse.climate.copernicus.eu/
Does this mean the winds are going to blow more and harder? Because that’s been happening already.
What This Means for the Future
If this pattern holds through the 2026 hurricane season and into 2027, the implications are significant. A sustained negative AMO phase typically brings:
Quieter Hurricane Seasons: Cooler water in the MDR means less fuel for storms and generally higher wind shear, which rips systems apart.
Rainfall Shifts: We could see a return to drier conditions in the African Sahel.
European Weather: A shifting jet stream often translates to cooler, wetter summers for parts of Europe.
Interesting, probably bad news for food security for Africa, but good news for the US Gulf states. What do cooler wetter summers in Europe look like, historically?
Forecasting ENSO in spring is notoriously difficult. Models often overestimate El Niño strength this time of year when atmospheric coupling is still developing. Early in the development, the models also tend to have a large range in outcomes as shown in the image below. Forecast confidence, however, improves significantly by early summer. This is why serious forecasters emphasize waiting until at least June.
A positive (warm) AMO phase reduces trade wind speeds in the tropical Atlantic, whereas a negative (cold) phase tends to enhance them, impacting atmospheric pressure and hurricane formation.
