El Niño forms in the Pacific, with NOAA warning it could become one of the strongest on record

NOAA has confirmed that El Niño conditions have formed in the Pacific, giving forecasters a new and more concrete warning sign for a weather pattern that can reshape rainfall, heat, drought and tropical-cyclone activity across large parts of the world.

The U.S. Climate Prediction Center said in its June outlook that there is a 63% chance the event becomes very strong in the November-December 2026 or December-January 2027 window. That makes the current Pacific warming signal not just a forecast possibility, but an established event that could keep intensifying over the next several months.

The confirmation comes after the World Meteorological Organization warned on June 2 that El Niño had an 80% chance of forming before September and a 90% chance before November. Celeste Saulo, the WMO secretary-general, said the spread across model forecasts was still wide, underscoring that forecasters were working inside a meaningful band of uncertainty even as the odds of formation rose.

El Niño is the warm phase of the El Niño-Southern Oscillation, the recurring shift in Pacific ocean temperatures and winds that can alter weather patterns far beyond the tropics. NOAA says its outlook is based on models and recent observations from a multi-member forecasting team, rather than on a single signal.

What NOAA is saying

The most important part of the new outlook is not just that El Niño has formed, but that NOAA sees a substantial chance of a strong event later in the year. The agency’s June strength probabilities show a 63% chance of a very strong El Niño in the late-fall-to-midwinter window.

NOAA’s Relative Oceanic Niño Index page, which is updated monthly, explains that warm RONI values above plus 0.5 C correspond to El Niño conditions. That gives forecasters a standard way to track whether the warming in the tropical Pacific is holding, strengthening or fading.

AP reported that NOAA’s confirmation is now the clearest official sign that the Pacific signal has moved from watch status to active event status. That matters because the closer an El Niño gets to peak strength, the more attention agencies give to the regional impacts that often follow.

How the timeline developed

The latest official development follows a short but important sequence. On June 2, the WMO warned that El Niño was increasingly likely to form. On June 11, NOAA confirmed that conditions have now formed in the Pacific and published its updated strength outlook.

That sequence matters because it shows the forecast picture has moved from possibility to confirmation in less than two weeks. It also shows that the main uncertainty has shifted from whether El Niño would emerge at all to how strong it will become and how long it will persist.

Forecasters will now be watching the tropical Pacific through summer to see whether warming accelerates, levels off or weakens. The late-summer and early-fall readings are especially important because they often help determine whether the event peaks in autumn or winter.

Why the event matters

El Niño can affect weather far from the Pacific because it changes the way heat and moisture are distributed in the atmosphere. When the event is strong, those shifts can become easier to detect in regional rainfall and storm patterns.

AP reported that one of the most common impacts is heavier rain in the southern U.S. and western South America. The same report said El Niño can also be linked to more intense heat waves in India and to drought, wildfire and heat risks in Australia.

The storm implications are also significant. El Niño often dampens Atlantic hurricane activity while increasing Pacific hurricane activity, which is why the event is monitored closely during tropical-cyclone season.

For governments, utilities and farmers, the concern is not abstract. A strong El Niño can affect planting schedules, water storage, power demand and disaster planning, especially where heat and rainfall timing are already near critical thresholds.

What forecasters are watching next

The next major question is whether the event keeps strengthening through the rest of the summer and into fall. NOAA’s outlook suggests the biggest odds of a very strong event sit in the November-December 2026 and December-January 2027 periods, so the coming months will show whether that projection holds.

There is still uncertainty, and WMO has not endorsed the label “super El Niño.” That caution is important because strong El Niño events can still produce different local outcomes depending on how ocean temperatures, winds and broader atmospheric patterns evolve.

Some scientists quoted in media reports have described the event as potentially historic in scale, while WMO has emphasized that model spread remains large. The difference is a reminder that forecasters can agree on elevated risk without agreeing on the exact peak intensity.

Why it is being watched so closely

The last recent El Niño, in 2023-24, was one of the strongest on record and helped contribute to record global heat in 2024. That history is one reason the current event is drawing so much attention from forecasters and climate scientists.

If this El Niño strengthens as NOAA expects, agencies in the Americas, Asia and Australia are likely to keep refining their seasonal outlooks. Those updates will matter for hurricane planning, drought monitoring, reservoir management and crop forecasts.

For now, the main takeaways are straightforward: El Niño has formed, NOAA sees a meaningful chance it becomes very strong, and the likely impacts could reach across rainfall, heat and storm patterns on multiple continents through late 2026 and early 2027.