When something that climate scientists have spent their careers studying begins to move more quickly than their models predicted, a certain kind of uneasiness descends upon them. Sometime early this year, that feeling appears to have reached NOAA’s Climate Prediction Center, and it hasn’t gone away.
Recently, Nathaniel Johnson, a research meteorologist on NOAA’s El Niño forecasting team, described the ongoing shift in the Pacific Ocean as “One of the most rapid transitions that I’ve seen.” This is not a casual statement from someone who has been trained to speak carefully. Johnson has spent enough time observing these cycles to understand what constitutes normal. Apparently, this isn’t it.
The El Niño–Southern Oscillation, or ENSO, is the slow, rhythmic breathing of the tropical Pacific that subtly regulates a large portion of the global weather. Every two to seven years, the system swings back and forth between El Niño and La Niña, two warm and cool phases that affect rainfall, drought, wildfire risk, and hurricane seasons. 2024 became the hottest year in recorded history because of the last major El Niño event, which peaked in 2023 and 2024 and was one of the five strongest ever. Now, it seems like another one is developing—and developing rapidly—before the world has had a chance to truly recover.
What’s getting attention is how quickly this specific transition is happening. El Niño events typically take months to develop as trade winds weaken and warm water moves east across the Pacific toward South American coasts. However, current ocean conditions indicate that this change is occurring at a rate that seasoned observers find nearly impatient. According to current forecasts, El Niño may form as early as May and has a 25% chance of becoming “very strong” by November, which would result in sea surface temperatures rising more than 3.6 degrees Fahrenheit above average. There is currently an 80% chance that El Niño conditions will form between June and August of this year, according to the World Meteorological Organization. It’s not a projection from the fringe. That’s almost a consensus.
It’s difficult to ignore the practical implications of those figures. Famine, civil unrest in tropical regions, devastating droughts in parts of Africa and South Asia, and catastrophic flooding along the U.S. Gulf Coast have all been connected to previous El Niño events. Warmer Pacific waters cause the jet stream to shift southward, rerouting rainfall and warmth to areas that weren’t ready for them while leaving others dry and exposed. This process is almost incredibly straightforward. The 2023–2024 event demonstrated the extent to which a single ENSO cycle can push global averages into areas that appear genuinely concerning on a chart when combined with already rising baseline temperatures.
Timing is what gives this moment its unique feel. Climate scientists have long recognized that El Niño events are now more powerful due to human-caused warming. There is a claim that the baseline has changed, with each new cycle beginning on a warmer floor, causing its peaks to fall in locations that were unimaginable in earlier records. It’s still unclear if the intensity of this impending event will be higher than or equal to that of 2023–2024. Johnson would probably acknowledge that there is a lot of uncertainty in the models at this point.
Climate watchers are running their forecasts, updating their probabilities, and waiting to see what the Pacific decides to do next. They are positioned somewhere between cautious fascination and concern. It turns out that the ocean has its own schedule, and this year it seems to be ahead of everyone else’s.
