Finally…El Nino is Here

Earlier this month NOAA announced that a very mild El Nino had set up in the southern Pacific Ocean.  Seems like we’ve heard this before, and Corey Davis, Applied Climatologist with the State Climate Office of North Carolina says it was actually 12 months in the making:

“Its been an interesting saga just to track this event over the past year. We really thought back in November there was a high likelihood that we would have an El Nino event in place but we really never saw those surface temperatures stay quite warm enough for that or the atmospheric impacts that usually come with it. We are seeing an increased rainfall over the central Pacific as well as those above normal surface temperatures over the last month.”

As we mentioned, we’ve heard this before, but Davis says this one looks like it’s here for the foreseeable future:

“Based on the sub surface temperatures it looks like we will have continued warming in this region – so that is why they put out the El Nino advisory, which means that it is here now and at least looks like it will stay through the spring and summer. We don’t know if it will strengthen though.”

And this event is a little different place than the usual El Nino says Davis:

“With a classic El Nino event we will see warmer than normal sea surface temperatures from the central Pacific going east all the way to the coast of South America. But this is just one smaller region in the central/west Pacific.”

The location is making it difficult to assess the effects according to Davis:

“Historically there are a handful of times we have seen this and they all carry different impacts. Some of them will bring above normal active hurricane activity in the following summer and fall. And some will see below normal activity. We just don’t have enough events in the past to make a good assessment.”

Another aspect of this El Nino that’s making it difficult to predict the effects is the time of year:

“Usually the winter time is when we have the most predictability, because that is when the jet stream is a little stronger. So if we know that an El Nino event will be in place for the winter, we will generally have a storm track to the south that will bring more precipitation. As we go to the spring, the jet stream starts to weaken and is weakest during the summer. Historically with strong El Nino events we have seen cooler and wetter springs, so its one possibility for this year, but this is a weaker event so its tough to know for sure.”

Historically, an El Nino is a drought breaker for the south and west late in the summer into the fall, but Davis says the characteristics of this one makes it hard to say:

“We have done some research here that says El Nino events tend to emerge during the spring so it will be interesting to monitor that over the next few months. If we don’t have a very strong El Nino event by then, chances are the rest of the year we wont see another one for the coming fall or winter.”

Applied Climatologist with the State Climate Office of North Carolina, Corey Davis.\

For more from the State Climate Office on El Nino click here

Image courtesy State Climate Office