El Niño Expected to Last Into 2016; May Bring Moisture, Cooler Temps

By Andrew Bernier
Published: Thursday, June 11, 2015 - 4:39pm
Updated: Friday, June 12, 2015 - 12:44pm
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(Photo by National Oceanic and Atmospheric Administration)
Average sea surface area temperature (SST) anomalies (Celsius) for the week centered on June 3, 2015. Anomalies are computed with respect to the 1981-2010 base period weekly means.

After speculation of El Niño possibly forming this year, nearly all climate models suggest it is forming, and may stick around for a while. But what does that mean for Southwest weather?

The National Oceanic and Atmospheric Administration reports water temperatures in the equatorial Pacific warmed during May. From this, climate models now predict an 85-percent chance El Niño will persist into the 2016 winter.

Ken Waters with the National Weather Service said past moderate to strong El Niños have often brought wetter and cooler temperatures across the South, but that is no sure bet.

“However, it does give us a much higher chance of getting some significant precipitation, especially over the winter time," said Waters. "That’s generally the most likely time when you’re going to see the big effects in Arizona.”

Winds at the equator blow from the east, upwelling cooler water from below and pushing warmer water farther west towards Asia. But in El Niño, these winds can weaken, allowing warmer water to ebb farther east toward the Americas. Warmer water increases atmospheric moisture, and can be picked up by westerly winds and carried into the southern United States.

Typical precipitation departures from late fall (November) through winter (March) during a moderate to strong El Nino. (Photo by NOAA - CPC)

Typical temperature departures from late fall (November) through winter (March) during a moderate to strong El Nino. (Photo by NOAA - CPC)

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