AUSTIN (KXAN) — Each month NOAA and the Climate Prediction Center release their updated guidance on the El Niño Southern Oscillation (ENSO). Meteorologist Nick Bannin spoke with Tom Di Liberto, a climate scientist at NOAA’s Office of Communications, just after the latest El Niño forecast was released about the newest expectations for the months and seasons ahead.
Meteorologist Nick Bannin: Tom, the fresh data on El Niño is now out and the odds of a strong El Niño are now 2 out of 3. What are you thinking that means for us here in America this winter?
Tom Di Liberto, Climate Scientist at NOAAs Office of Communications: So a strong El Niño doesn’t necessarily mean that the impacts are going to be strong. But what it does mean is that it’s going to have a more consistent, potentially, impact on the way our atmosphere sets up across the United States this winter.
Bannin: So we’ve seen that El Niño has been very obvious in ocean temperatures in the eastern Pacific, but we’ve been waiting on a stronger response from the atmosphere. Are we starting to see that now?
Di Liberto: Yes, we have started to see that. Through the month of July, we saw come the tell-tale atmospheric signs in the Pacific Ocean get a little bit stronger. We saw there being an increase in the amount of precipitation around the Date-Line, a reduction in precipitation across Indonesia and we saw the trade winds be a little bit weaker, too, than average, which are all kinds of things you’re looking for to see an El Niño not only exist, but also develop and strengthen.
Bannin: Now, we’ve also been seeing the incredibly warm temperatures on the sea surface in the Atlantic. What sort of impacts and potential mitigating impacts could that have on El Niño?
Di Liberto: So this is an interesting time, because El Niño is occurring against the backdrop of the global oceans just being so incredibly, record breakingly, warm. And, honestly, the impacts between the interplay between the above-average ocean temperatures, and, let’s say, the Atlantic and the El Niño impacts could either sometimes help each other out or actually work against each other.
An example of this is the hurricanes across the Atlantic. Normally during El Niño , you tend to see below average hurricane activity in the Atlantic, but with the oceans this warm, that actually serves to usually increase the amount of activity in the hurricane season. So, even though we have an El Niño this year, it might not mean the below average year that normally comes with El Niño.
Bannin: Could the warm Atlantic then suppress some of the typical expectations that we would expect for a strong El Niño in the winter?
Di Liberto: So, it won’t necessarily impact the development of this El Niño in the wintertime. What’s going to potentially impact the atmospheric connection between El Niño in the tropics, and in the mid latitudes, where we live, is the fact that not only is the eastern Pacific Ocean warm, but the Western Pacific Ocean is also warm.
Normally, during El Niño, the Western Pacific is cooler than average. But, because it’s so much warmer than average, that might lead to less of an influence on the atmosphere than we normally see. And that could then, potentially, lead to there being less of an impact in the United States from El Niño. But a lot of that is still really up in the air. And it’s a lot of uncertainty.
Bannin: We get an update from the Climate Prediction Center and NOAA once a month about the status of El Niño and their prediction predictions going forward. What new information about El Niño could we hope to gather month to month from now, or is it pretty much locked in that these updates aren’t really as telling as they once were?
Di Liberto: So the thing that we’re really looking to right now is what we call “westerly wind bursts” across the Pacific Ocean. These are time periods where the trade winds either really weaken or actually reverse themselves for days or weeks at a time. This could actually help set the stage and bring more warm water from the Western Pacific to the eastern Pacific fueling this developing El Niño. So the final strength of El Niño this winter actually relies a lot upon what we’re seeing in the atmosphere right now.
So we’re still in the thick of that. So, throughout August, the beginning of September, we’re really paying attention to how the winds interact in the Pacific Ocean, because that might give us a little bit more information about how strong the cell Nino ends up this winter.
Bannin: So we’ll gain more knowledge about what we anticipate the strength of El Niño to be in the winter, but the strength does not necessarily have a huge correlation with what patterns end up evolving in the winter in the United States?
Di Liberto: Right, so El Niño is one player of what the patterns will look like across the United States. It’s not necessarily the only player or even the strongest. The stronger the El Niño actually is, usually that means it might have more of an influence on the weather that happens across United States this winter, but by no means is it the only thing that can have an influence. Is it a good thing to provide more/better predictions of what’s gonna happen? Yes. But we’ve seen multiple years with El Niños, kind of, give different outcomes across United States. It’s another reason why when you’re looking towards this winter, it’s really important to keep paying attention to the weather forecast as we get closer to that time
Bannin: No suggestion that El Niño has any impact on the type of heat and dry air that we’re dealing with here in Texas.
Di Liberto: Yeah. So, the there’s been an incredible amount of heat across the southern tier the United States, especially in Texas. Now, I wouldn’t necessarily look towards El Niño to be the main influence on what we’ve been seeing currently, not only across the southern United States, but really across the globe as well.