‘Blame it on El Niño.’
Those are the words emblazoned on the coffee mug on the desk of Dr. Ben Kirtman — Dean of the Rosenstiel School of Marine, Atmospheric, and Earth Science at the University of Miami.
A California native who grew up in Santa Barbara, Kirtman has vivid memories of the 1982-83 El Niño which brought torrential rainfall across Southern California. Up to 18 inches of rain fell between Santa Barbara and L.A. in early March of ‘83, and Kirtman’s family had one of those rare Southern California houses with a basement.
“My introduction to El Niño was pumping the basement out, so that’s why I had such a fascination with it.”
That flooded basement spurred Kirtman into a career of forecasting and climate science: working on being able to predict patterns like El Niño months ahead of time. That work has grown into one of the main tools now used to predict El Niño months in advance.
Kirtman is the lead creator of the North American Multimodel Ensemble, or NMME, a partnership of U.S. and Canadian climate modeling centers that has issued seasonal forecasts every month since August 2011. The idea is rather simple; by considering many different climate models instead of just one, the underlying uncertainty can be taken into account when forecasting out weeks or months in advance.
“Suppose [a model] predicted we were going to have a 10 degree El Niño or something like that, then you’re stuck with it. You don’t have enough uncertainty,” Kirtman said. “When you use multiple models … then you start to get a better range of possible outcomes.”
And right now, as Kirtman puts it, the agreement between the models has been remarkable — a very strong El Niño is underway and getting stronger. There are some differences between just how strong or record-breaking this event will get between the models, but those are differences between the strongest El Niño ever measured and the strongest ever measured using only certain metrics — it is a beast regardless.
What is less clear are the implications for the world’s weather and climate over the coming months, and that is precisely what Kirtman’s NMME is designed to help with.
The hype surrounding Super El Niño has been big in California and across the globe as it breaks new records week after week. There is little doubt this massive event will influence global weather, the remaining doubt lies in exactly what that weather will look like over the next year. We actually have enough of an idea to draw some soft conclusions, such as a wet winter across most of California and the southeastern United States, but that is not the same as forecasting catastrophic floods.
Nonetheless, even if no biblical floods or droughts are predicted, or even if this event does not break every record, it is worth taking this El Niño seriously.
“This is a fantastic opportunity … we have time to prepare,” Kirtman said. “Earthquakes just happen, boom … but here, we know it’s coming.”
The numbers behind this El Niño are real and 'absurd'
A quick refresher on El Niño; every two to seven years, warm water builds up in the eastern Pacific Ocean along the equator south of Mexico. This isn’t a small change, it’s a rather sudden pool of warm water spanning thousands of miles that directly influences the atmosphere above it, and has been associated with everything from floods to drought worldwide.
Last week, the sea surface temperatures in the key monitoring region broke past a notable barrier. At 5.6 degrees Fahrenheit (3 degrees Celsius) above average, the El Niño tied the previous record (on a weekly basis), and was by far the earliest in the year temperatures have ever been this warm.
As of October 2, satellite estimates put that anomaly around 6 degrees , and it is expected to grow stronger.
El Niño in a league of its own
The Oceanic Niño Index (ONI) of Major El Niños in the records versus the current event.
1877-
78 (reconstructed)
2015-
16
1997-
98
1982-
83
1972-
73
2026
observed
NMME
forecast
Chart explorer. Use arrow keys ↑ ↓ ← → to navigate.
−101234
Average peak +4.1C
Source:NOAA ERSSTv5, NOAA CPC weekly index. 1877 reconstructed from ship reports. Climate forecast: NMME ensemble member middle 80%.Chart:Sean Macaday, Sacramento Bee
“(The temperatures) are at absolutely just absurd levels,” said Kirtman, who points these numbers being partly a result of El Niño and partly from climate change.
It’s these numbers, which are pushing records to new heights, which has spurred the growing buzz around El Niño for better or worse. The NMME, for example, puts peak warming at over 7.2 degrees Fahrenheit this winter.
And then there is another measure, made official by the National Oceanographic and Atmospheric Administration this year, that takes into account the relative temperature anomaly against the background of the warmer ocean from climate change. This Relative Oceanic Niño Index (RONI) makes our ‘Super El Niño’ look a bit less super (even if still very strong). By this gauge, the anomaly averaged over a 3-month span sits at around 3 degrees Fahrenheit.
Debate has been raging in online meteorology and climate circles over the past several months as forecasters try to find the best and most appropriate way to communicate this to the public while gauging the true level of seriousness it demands. Still, the presence of these two measuring sticks has led to public confusion of if this El Niño is actually a big deal or not.
Kirtman’s take is simpler: The Relative Oceanic Niño Index is a “forecasters tool” for helping shape the seasonal forecast. He adds that what matters most isn’t how much warmer the ocean heats up above normal, but how warm the water actually is.
“The climate system cares what the total temperature is. How warm is the sea surface temperature? How moist is the air?” he said. “Climate system doesn’t do anomalies. That’s a human construct.”
And for what it’s worth, Kirtman’s ensemble still puts a record-breaking El Niño on the index at more likely than not, breaking the previous record set when his basement flooded 43 years ago.
“The energy for these storms that come into California, all of that juice is from the warm temperatures,” he said. “It is juicy out there.”
And as El Niño continues to strengthen, it’s leaving its mark. In the Atlantic, not a single hurricane has formed yet, a record for this late into hurricane season, due to ferocious wind shear brought on by El Niño. Storms “get halfway across the basin, they just got shredded to bits by the shear,” Kirtman said.
Meanwhile, the eastern Pacific Ocean has been booming; thanks to the warm waters El Niño provides, Hurricane Polo explosively intensified into a Category 5 in late September before making landfall in Baja California Sur earlier this week.
Off California, the event “has matured so fast and so rapidly. It’s already warming waters along the coast,” Kirtman said. Warmer water and long-term sea level rise have already lifted sea levels along the coast, and big swells from distant storms are damaging shorelines. That is not even considering the incoming planetary coastally-trapped Kelvin Waves that are now arriving, and could raise sea levels by another 6 inches.
“Even if we don’t get more storms, you’re going to see coastal erosion big time.”
For the most part, seasonal El Niño forecasting works
Forecasting seasonal trends such as increased rainfall or a warmer winter is markedly easier than forecasting the weather two weeks in advance.
That’s because climate models — the same ones Kirkman’s NMME factor together — are different from the weather models that populate your phone app. It’s not about forecasting specific storms on specific days, just trends, and the NMME has shown real skill in doing this.
El Niño is even easier: ocean water changes slowly over time and is inherently less chaotic than the atmosphere. All the heat from El Niño will linger for months. That gives the atmosphere an extended window to respond. It’s this stability which helps make seasonal forecasting possible.
The NMME approach to climate models has paid off. It has outperformed the best single model over most of the globe and has done well for El Niño events.
When it comes to where the rain will fall, Kirtman’s read follows from where the warm water sits. This is currently the furthest “east-leaning” El Niño at this point in the year on record. Events centered farther west can push storms north, “maybe up to Washington State,” he said. Events focused towards the eastern Pacific, like this one, tend to shift the storm track south, bringing more storminess from “San Francisco, Sacramento down.”
The NMME agrees. The latest September run of the model shows well above average rainfall expected across California and the Southern United States, beginning in December and lingering into at least February.
“If I was betting … this is looking like an Eastern Pacific event,” Kirtman said. “I would be betting for enhanced rainfall” in California.
Models are not perfect, but the blind spots are understood
The models have become better at forecasting ocean temperatures, but although climate models have some skill at forecasting rain months out, it’s not nearly as reliable as it is for forecasting other factors.
Where the warm water sits is another weak spot. Studies have linked how far east the bulk of the warm water sits in El Niño to increased rainfall across the California and the southwestern United States. Coincidentally, research published by Kirtman earlier this year shows that while the best climate models do well with the strongest El Niños, they struggle at capturing this east-ward tilt. That’s relevant, as this year’s El Niño is the most east-tilting of any event this early on, meaning that some of the events effects could be underestimated.
Then there are more blind sports that reside in the rest of the atmosphere itself. Kirtman said the factor he’d watch most is the Madden-Julian Oscillation, a pulse of tropical storminess that circles the globe every month or two. California’s El Niño rainfall signal typically peaks in February. If the oscillation passes through in its dry phase then, it could noticeably reduce rainfall.
“My dad’s going to tell me you blew the forecast, buddy,” he said.
If it arrives in its wet phase instead, “then things could get messy.”
That’s why forecasters will keep updating long-range outlooks with shorter-range ones through winter. The next run of the NMME will be released October 8.
Perhaps the most important point to remember when it comes to seasonal forecasting is that it cannot predict any single storm or atmospheric river, only just how more or less likely those underlying conditions might be. No single spot across California is likely to see severe flooding on its own, and we will not have a forecast for that until days or a week or two ahead of time. Across the entire state though, the odds of any single spot seeing floods does rise.
What is hype and what is useful
There will continue to be further headlines surrounding El Niño this month and through winter. The numbers demand it.
For Kirtman, the forecast’s real value, what it actually is good for, is lead time.
For California, it’s to prepare for that possibility of extra rain. “Check your roof.” He said, and reminded that any time spent preparing for heavy rain, flooding, and mudslides is time well spent. Two weeks ago, California Gov. Gavin Newsom declared a statewide state of emergency ahead of the potential for increased rain and coastal flooding this winter.
There’s also time to consider what comes after El Niño passes. A wet winter would lead to increased vegetation growth, which will die during a likely La Niña next year and become “kindling for fire,” Kirtman said. “It’s the follow-on effects that we have to start thinking about pretty soon, there’s a really good chance we’ll see La Niña next year.”
“We can do this. Let’s buckle down. We can get it done.”
This story was originally published October 5, 2026 at 8:00 AM with the headline "El Niño hype is loud. The numbers back it up, but here’s what they really mean."
Sean Macaday covers the weather for McClatchy Media in California. Originally from Chicago, Sean worked 6 years covering the weather on local television in Minnesota. He holds a bachelor’s degree in meteorology and marine science from the University of Miami.
