Monday, December 28, 2015   |   Critical Weather

The Monster on Our Minds: Making Sense of El Niño 2015-16

Recent news has many concerned that the El Niño for 2015-16 will be an event unlike any other—a “Monster El Niño”. Many towns are preparing for what they believe will be a catastrophic flooding event, while other parts of the country are ready for unusually dry, warm weather.

The current strong El Niño has been in place for some time. In fact, it’s been active since the beginning of this summer, and it’s already had an effect on the tropics. But what severe weather can we actually expect in the coming months? El Niño is an event that typically takes place December through March, and it’s sure to create some interesting weather for the United States.

What is El Niño?

El Niño generally starts to develop when easterly trade winds decrease and warmer Sea Surface Temperatures (SST) start to shift eastward. This unusual warming of the equatorial waters in the Pacific Ocean is what creates El Niño.

“When you have El Niño weather, you get an upwelling in temperatures of the water near the equator in the Eastern Pacific,” said Scott Ford, Senior Customer Meteorologist. “That in turn starts to affect the whole world’s weather patterns.” El Niño is the opposite of La Niña, which is a cooling of the waters. Both situations can lead to unusual weather—in a macro and micro sense—for extended periods of time.

ElNino1

*This graphic depicts the typical NON El Niño pattern. It shows the upwelling of cooler water in the eastern pacific that moves westward along the equatorial region, and the warmer waters northeast of Australia and around the islands.

ElNino2

*This graphic depicts the same as image 1, with the addition of clouds and rain over the warmer bodies of water that help feed showers/storms that will then move east. This can lead to an El Niño cycle birth.

ELNino3

*Showers/storms move over the central pacific due to a direct correlation of the warmest water propagating to the east. This helps curtail the cooler upwelling off the South American coast, thus expanding the cycle of El Niño .

Most meteorologists use SST data to find 80 degree water temperatures, because it’s the magic number in which tropical systems develop. They also use it to monitor for El Niño and La Niña potential.

In El Niño years, the weather in the U.S. can change dramatically. Many are wondering how this particular El Niño will affect their winter season.

El Niño in the U.S.

Depending on where you live in the U.S., El Niño will affect you differently. The southern United States, during a typical El Niño pattern, will be cooler than normal and precipitation will be increased. For the southern areas of California this could be a possible solution to its ongoing drought problem, which is great news. The northern tier of the U.S. tends to be warmer and drier than normal.

“Specifically in the U.S., if you get a sub-tropical jet stream that’s coming off the Pacific Ocean—like from Hawaii moving northeast—it tends to lead to a deviation of typical weather patterns for the winter,” said Ford. “In the southeastern U.S., we usually get additional precipitation and occasionally a good ice storm. The west coast tends to get very wet because of El Niño, which would actually be good for them right now with the drought.”

Again, things like El Niño are hard to predict and can change at any moment.

What else can El Niño affect?

In addition to the weather, El Niño can affect several ecological factors.

What will happen with El Niño 2015-16?

This year, the Pacific Ocean temperatures are at the very top of the scales in terms of strength of El Niño. “It is one of the strongest ones that we have ever seen,” said Kevin Nugent, Forecast Meteorologist at Baron. “The waters off the coast of Mexico were also well above normal over the past few months. I believe that’s why we had the second most active hurricane season in the eastern Pacific. That includes Hurricane Patricia, the strongest hurricane ever measured, and category 4 Hurricane Sandra.”

While it’s impossible to predict whether or not El Niño 2015-16 will cause a catastrophic tornado or severe flood, Ford believes that it will affect the weather in a general sense. He also urges everyone to make sure to get weather updates from reliable websites. “We are so desensitized to severe weather now. Sometimes websites have to hype up a story to get clicks,” said Ford. “So make sure you are getting your updates on El Niño from credible news sources.”

This is currently one of the strongest El Niño’s on record, but weather is highly unpredictable. “Snow is a possibility in the southern tier of the U.S.—flooding too,” said Nugent. “But we really won’t know anything definite until it’s closer to an event. Actually, the highest possible chances for flooding will likely be in California and Texas.”

Stay tuned for more updates as El Niño 2015-2016 continues.

*The graphics in this article are available on the Baron Support site for use in Omni.

UPDATE 12/28/15: As one would expect in a very strong El Niño year, we have seen a very active subtropical jet over the past few weeks, which has caused widespread flooding for much of the southern U.S. from Texas to Alabama. These same areas in the Midwest and Northeast have also seen record warmth. Looking forward over the next 1-2 weeks, long-range forecast models are indicating that sections of central and southern California will begin to receive much needed rainfall.