An El Nino is building in the Pacific, and forecasters are using language they typically avoid.

The US National Oceanic and Atmospheric Administration said Thursday that this year’s event has an 81% chance of reaching “very strong” status — the highest category the agency recognizes — by fall. If it does, it will rank among the most intense El Ninos recorded since tracking began in 1950.

“This is not a run-of-the-mill El Nino,” said Daniel Swain, a climate scientist with University of California Agriculture and Natural Resources.

What Is Actually Happening

El Nino is a natural warming of the equatorial Pacific Ocean that reorganizes weather patterns worldwide. It has always existed. It is not caused by climate change.

But it interacts with it — and that is the crux of this forecast.

The event formed only last month. It blew straight past the weak stage and is already classified as moderate, with no sign of slowing. Ocean temperatures in the key Pacific regions used to gauge El Nino strength are at or near record highs for this point in the year.

Part of the reason is straightforward: this El Nino is developing on top of ocean warming already driven by the burning of coal, oil and natural gas. The baseline has shifted upward, so the peak sits higher.

“It’s pretty extreme,” said Emily Becker, a University of Miami scientist who works with NOAA’s El Nino forecast team. “Not unprecedented, but very unusual.”

The 1997 Comparison — and Why It Matters

Becker expects this event to rival the 1997-1998 El Nino. Some meteorologists think it may surpass it.

That comparison carries weight, because the human cost of the 1997 event is documented.

According to the World Bank, the El Nino that began that year contributed to roughly 23,000 deaths in weather disasters, drove up poverty rates in some countries, and cost governments as much as $45 billion.

That was the last time an El Nino of this magnitude collided with the world. The world it hits now is warmer.

Swain flagged precisely this distinction. Unlike previous super El Ninos, this one arrives atop substantial background warming. That means, he cautioned, we should not necessarily expect the same impacts we have seen historically.

What Very Strong Actually Means

An important clarification: a “very strong” classification is based on Pacific ocean temperatures, not on the severity of resulting weather.

As Becker explained, it does not guarantee more intense extreme weather. What it does is raise the probability of those conditions occurring.

Odds, not certainties.

The Expected Effects

The most significant impacts are anticipated in fall and winter. Among the outcomes made more likely:

• Wetter winter conditions across most of the southern United States
• Warmer winter temperatures for the northern US and Canada
• Drier conditions in Indonesia
• A warmer and wetter eastern Pacific
• Droughts, heavy rainfall events and heat waves in various regions globally

The Hurricane Silver Lining

There is one genuinely favorable consequence.

El Nino typically suppresses Atlantic hurricane activity by increasing wind shear, which tears developing storms apart.

Colorado State University — the institution that pioneered seasonal hurricane forecasting — sharply lowered its storm count prediction on Wednesday, citing increased confidence in a strong or very strong El Nino.

Their revised outlook: overall Atlantic hurricane activity will be well below normal.

For coastal communities, that is meaningful relief.

The Thermostat Metaphor

Swain offered a description that clarifies why El Nino matters beyond regional weather.

Writing in a blog post, he explained that El Nino functions as a thermostat for global climate. It releases years of accumulated heat stored beneath the surface of the tropical Pacific, dumping that energy into the atmosphere.

That heat eventually dissipates — but not before warming the entire planet on its way out.

This is the mechanism by which a Pacific phenomenon becomes a global temperature event.

Records Likely to Fall

The forecast has climate scientists looking ahead to 2027.

Many now expect that year to break the global high temperature record set in 2024 — itself a product of the last strong El Nino. The reasoning involves lag: heat released during an El Nino takes time to fully register in global averages.

Zack Labe, a climate scientist at Climate Central, framed it in terms of probability.

A strong El Nino, he said, raises the odds of dramatic new climate records over the next six to twelve months. He described it as offering a preview of a warmer world still to come.

What to Watch For

The forecast is not a prediction of catastrophe. It is a statement about elevated risk across a range of outcomes.

Southern US states should prepare for a wetter winter. Northern regions may see an unusually mild one. Indonesia faces drought risk. Atlantic coastlines get a quieter hurricane season.

And globally, the thermometer is likely to climb.

Whether that produces a repeat of 1997’s death toll and economic damage depends on preparation, infrastructure and luck. What it will almost certainly produce is data — a real-world measurement of what happens when a powerful natural cycle fires on an already overheated planet.