Although a La Niña event has yet to be officially classified, there is a respectable cold tongue in the equatorial Pacific! 🌊
The 30-day relative Niño 3.4 Index (-1.02˚C) is now in moderate La Niña territory, lower than the value at this time in 2022 (-0.94˚C) and 2021 (-0.94˚C).
With abundant off-equatorial warmth in the tropics, the relative index is a better indicator of the potential for anomalous convection. Thus, it has high utility in a warming world and can be viewed as an alternative to traditional indices.
The La Niña signature currently covers the eastern and central equatorial Pacific, having a classical look (not a central-based event at this point).
While a spell of westerly winds will move across the Pacific during early November, I think a moderate (relative) La Niña will still be in place come December, being an important global climate driver into early 2025.