Trust the satellites, not the "super El Niño" headlines, to size up this event

Is this the "strongest El Niño ever," or just the loudest? The honest answer is that it is both big and uncertain, and the best tool for telling those apart is not a headline. It is a series of satellites that has been measuring the height of the ocean since 1993.

Satellites say it rivals 1997, but shape matters more than size

On October 23, NASA's Earth Observatory published a comparison of sea surface height maps from October 13, 1997 and October 12, 2026. The two come from different satellites, TOPEX/Poseidon and Sentinel-6 Michael Freilich. Josh Willis of NASA's Jet Propulsion Laboratory says the strength of altimetry is a 35-year record from nearly identical satellites flying almost the same ground track, with each mission overlapping the next. His read, per NASA, is that this year's event "is on track to be even bigger" than 1997.

The detail that matters, in our view, is shape rather than size. This year's event came on much more suddenly than 1997's. Yet as of October the two look alike: sea level low in the west, high in the east, and warm water reaching all the way to South America. The 2015-16 event had a different character, with the warm water not pushing up against South America to the same extent. Its rain fell more over Central America and the southeastern U.S.

Bigger is not the same as better understood

Forecast numbers make the "record" label tempting. Zeke Hausfather, who tracks seasonal forecast models on his Climate Dashboard, wrote in September that model runs put the peak around 4.1C in the Niño 3.4 region, well above the prior record of 2.75C in 2015-16. Those are projections, and the same post is candid about the catch. All eight past strong events in his comparison are forecast to be exceeded this winter, so "we are extrapolating well outside the training data."

We find that admission more useful than any superlative. Past strong events delivered the expected wet or dry outcome in 86% of region-events (176 of 205), according to his tally. That is a strong track record. But it partly restates the evidence the textbook patterns were built on, especially 1982-83 and 1997-98. So the data supports "shift the odds," not "guarantee the outcome." NOAA's Climate Prediction Center, as Hausfather quotes it, says the same: with an event of this magnitude, the chances of El Niño-consistent impacts are larger, "but they are not guaranteed."

Where the hype outruns the evidence

The sloppiest claim in circulation is the automatic 1997 playbook: California floods, Indonesian drought, done. Some of that is well founded. Hausfather finds Indonesia's autumn drought the single most reliable El Niño impact, and all 13 models he tracks agree on it. The risk there is fire.

California is murkier. One explainer site argues that this year's warming pattern mixes eastern and central Pacific traits, which would change the teleconnections. That is a single non-peer-reviewed web page, so we treat it as a caution rather than a finding. Willis himself is blunt: "There's always a bit of a dice roll here," and looking like 1997 "doesn't mean it will be exactly the same."

We would also be wary of any single comparison figure from web explainers, such as damage tallies or "63% chance" probabilities. The cleaner number, in our view, is NOAA's October 8 outlook, as NASA's Earth Observatory reports it: an 83% chance of a strong-to-very strong El Niño through the first three months of 2027.

Take it seriously, but distrust certainty

Our verdict: the satellites justify taking this event seriously, and also justify skepticism toward anyone selling certainty. The ocean's heat is measurable, and altimetry shows it is comparable to 1997. What that heat does to a specific farm, city or coastline depends on a chaotic atmosphere that no sea level map can settle.

For readers, the practical advice is dull but sound. Follow your national weather service's seasonal outlooks, which update as the winter unfolds. Treat "similar to 1997" as a prior, not a prophecy. And when a headline says "super," ask which index, which region and which forecast it is leaning on. The record is long enough now to answer that. Headlines rarely bother to.