El Nino Just About Gone
About this time a year ago we were discussing the fact that a strong El Nino was beginning to take shape in the subtropical Pacific. A year later we are now talking about its demise.
The area of above normal water temperatures between South America and Australia have reversed direction and are now trending colder. This is a tendency (a reversal) is something we have observed in past strong El Nino patterns. The reversal is a natural response in the subtropical Pacific as temperatures naturally go through these fluctuations.
After the second strongest El Nino on record past year, all indications suggest that we are headed to a La Nina by this fall and into the winter months.
The graphic below shows the change in temperature across the Pacific (blue/purple) since late February. The change has been quite dramatic in the past several weeks. As the temperatures continue to change to colder than normal by later this summer, the impacts of La Nina will likely begin by this fall and winter.
The change is also shown in heat content across the Pacific. Since March the heat content has dropped sharply in the key areas of the subtropical Pacific.
The long range computer modeling suggests the cooling trend will continue into 2017.
With the Pacific going through a big change to cooler conditions, we are mostly likely going to experience a different fall/winter pattern than compared to the past two years. As the strength of the developing La Nina comes into focus later this summer we can address what kind of impacts the La Nina will have on us this fall and winter season.