Five things you need to know about El Niño’s likely comeback – Image for illustrative purposes only (Image credits: Unsplash)
Sea surface temperatures across the central and eastern Pacific reached their second-highest March value on record this year, according to Copernicus data. That reading signals a high likelihood that the warm phase of the El Niño-Southern Oscillation will begin later in 2026. The pattern is developing against a backdrop of already elevated ocean heat and a warmer global climate than during the previous episode.
Current Conditions Point to a Shift
NOAA’s Climate Prediction Center reports that neutral ENSO conditions prevail now and are expected to hold through at least July. Forecasts from multiple centers show a transition toward El Niño becoming more probable after September. Significant uncertainty remains about the event’s final strength, though several models indicate it could rank among the stronger episodes on record.
The cycle typically recurs every two to seven years and lasts nine to eighteen months. Its timing is irregular, yet the current ocean warmth adds a new variable that forecasters are watching closely.
How the Pattern Works
El Niño forms when sea-surface temperatures in the equatorial Pacific rise above average for several months. The change disrupts the Walker Circulation, a large-scale atmospheric loop that normally moves heat and moisture westward. As a result, altered wind and pressure patterns spread through the tropics and beyond via planetary waves.
The three phases of the oscillation – warm, cool, and neutral – reorganize global weather each time they occur. The warm phase favors heavier rain in some areas and drier conditions in others, while also shifting storm tracks.
Expected Weather Shifts
Climate models anticipate stronger heat waves and more frequent extremes once El Niño strengthens. Wetter and stormier conditions are likely across the southern United States and northern Mexico, while the northern tier of North America trends warmer and drier. Atlantic hurricane activity tends to decrease because of increased wind shear.
Precipitation deficits become more probable in parts of the southern and western United States, potentially worsening existing drought. These changes arise from the same atmospheric reorganization that affects distant regions through teleconnections.
Amplified Effects in a Warmer World
El Niño itself is a natural ocean-atmosphere process, yet it now unfolds on a planet already warmed by human activity. The World Meteorological Organization noted that the 2023–2024 episode combined with background warming to intensify droughts, heat waves, and extreme rainfall across Latin America and the Caribbean.
Similar amplification is possible this time. The added ocean heat provides extra energy that can intensify rainfall where it occurs and deepen drought where it does not. Forecasters therefore stress that impacts could exceed those of earlier events even if the El Niño itself is only moderate.
Global climate connections mean the pattern’s influence will be felt far from the Pacific. Communities should prepare for the range of extremes that typically accompany the warm phase, while recognizing that no single event defines long-term climate trends.