It’s official – La Niña has finally emerged in the tropical Pacific. La Niña is the cool phase of the El Niño/Southern Oscillation, a pattern of sea surface temperature and atmospheric changes in the tropical Pacific Ocean.
We’ve been talking about La Niña’s arrival since spring of 2024, and although it took a little longer than initially expected, tropical sea surface temperatures finally exceeded the La Niña threshold of -0.5C in December.
There is a 59% chance that La Niña persists through February-April, followed by a 60% chance of neutral conditions in March-May. Most likely, this La Niña will be weak based on computer guidance and how late in the year La Niña conditions emerged. La Niña typically peaks in the winter, so there is not much time left for it to strengthen.
Given that La Niña is expected to be weak, a weaker influence over temperature and precipitation patterns is likely. That being said, temperature and precipitation patterns in October-December 2024 did resemble La Niña-like conditions, even though La Niña wasn’t officially declared during that time frame.
It’ll be interesting to see how things play out and what kind of an impact it has. Stay tuned!
