The strong 2015 El Niño is officially over.
El Niño dissipated and ENSO-neutral conditions returned during over the past month, as indicated by the expansion of near-to-below average surface temperatures (SST) across the eastern equatorial Pacific Ocean.
In addition to sea surface temperatures, other atmospheric conditions across the equatorial Pacific have also returned to neutral levels.
For the first time in 2016, atmospheric anomalies over the tropical Pacific Ocean were also consistent with ENSO-neutral conditions.
The demise of the 2015 – 2016 El Niño event is not surprising though, because sea surface temperatures over the equatorial Pacific Ocean have been cooling for the past two months.
However, the neutral ENSO conditions don’t appear to be poised to stay. It is now looking increasingly likely that La Niña will develop in the equatorial Pacific by mid to later Summer or early Fall.
NOAA’S Climate Prediction Center says there is a 75% chance that La Niña will develop by Fall or Winter of 2016. They have also issued a La Niña watch.
The expected development of La Niña is not surprising either. The likely onset of La Niña has been something that climate models have been indicating would occur for the past several months. In addition, La Niña events usually develop following strong El Niño events.
Of course, this is somewhat concerning because La Niña usually causes decreased wind shear over the tropical Atlantic. This boosts the chance of seeing a more active Atlantic Hurricane Season this year; however, that is by no means set in stone.