As the world keeps a wary eye on the Pacific, climate experts are sounding the alarm: El Niño is on the horizon, and its arrival could shape the weather across the globe for the rest of 2026 and into early 2027. The phenomenon, often dubbed the "Pacific's enfant terrible," is poised to return with a vengeance, bringing with it the potential for dramatic shifts in temperature, precipitation, and even the health of marine ecosystems.
According to the National Weather Service's Climate Prediction Center, the Northwest United States is bracing for a drier and warmer than average spring and early summer. The Center's forecast, released on March 19, 2026, projects that Oregon, Washington, Idaho, and Northern California will experience above-average temperatures and below-average precipitation in April, May, and June. But that's just the beginning. There's an 82% chance that El Niño will still be in place by the time winter rolls around, and a 33% chance that it will develop into a strong event—an outcome that carries significant implications for weather patterns and water resources.
NOAA's analysis from March 12, 2026, paints a similar picture, estimating a 62% likelihood of El Niño developing between June and August, climbing to 80% by the fall. The International Research Institute for Climate and Society at Columbia University goes even further, pegging the risk at 80% for as early as this summer. While the Pacific is still under the influence of La Niña, the cooler counterpart to El Niño, that phase is expected to end in April, ushering in a neutral period before the possible shift to El Niño conditions. Should the transition occur as predicted, scientists expect El Niño to strengthen through the autumn and peak between December 2026 and January 2027.
"If you want to make a really strong El Niño, this is the way to start," Oregon State Climatologist Larry O’Neill told local media, referencing the unusually warm reservoir of water currently lurking beneath the Pacific’s surface. "I think it’s more likely than not, we’ll see an El Niño." O’Neill’s assessment is backed by the deep, widespread warmth detected in the Pacific, a key ingredient for the development of El Niño. The chances of a strong event—defined by the intensity and persistence of warm sea surface temperatures—currently stand at about one in three between October and December, according to NOAA.
El Niño is no stranger to meteorologists or to those living in its path. The phenomenon, which occurs every two to seven years and typically lasts nine months to a year, is infamous for its ability to amplify the effects of climate change. It pushes up global average temperatures by an estimated 0.2 to 0.3 degrees Celsius and is linked to an uptick in extreme weather events around the world. The last El Niño episode, spanning 2023 to 2024, was the fifth strongest on record, although it stopped short of reaching the most extreme levels observed in the past.
For the Pacific Northwest, the implications of an El Niño year are significant. Historically, the region has seen warmer and drier winters during El Niño events, with the exception of a few very strong episodes that altered storm tracks and, somewhat ironically, produced large snowpacks. Since 1950, there have been six strong El Niños and three very strong ones. Yet, as O’Neill cautions, "With climate change, there are no guarantees that what happened in the past will happen again." The interplay between natural climate cycles and the overarching trend of global warming adds a layer of unpredictability to seasonal forecasts.
The winter of 2025-26, dominated by a weak La Niña, has already demonstrated the challenges of predicting weather in a changing climate. Despite La Niña’s typical association with cool and wet conditions, the Northwest received disappointing snowpacks: Washington reported just 61% of its average and Oregon a mere 24% of normal as of March 19, 2026, according to the Natural Resources Conservation Service. O’Neill attributes this shortfall not to a lack of precipitation, but to unseasonably warm temperatures. In fact, December 2025 through February 2026 marked the warmest such three-month period in 131 years of record-keeping, a statistic that underscores the extraordinary nature of recent climate trends.
Adding to the region’s climate woes is a massive marine heatwave that has gripped the waters off the West Coast since the summer of 2025. NOAA scientists report that this is only the third time on record that such an extensive and persistent marine heatwave has occurred outside of an El Niño event. The heatwave has raised coastal water temperatures by 3 to 4 degrees Fahrenheit above normal, with the northeast Pacific reaching a record high average temperature of 20.6 degrees Celsius (about 69 degrees Fahrenheit) on September 9, 2025. That’s nearly half a degree warmer than any previous measurement. At its peak last September, the heatwave rivaled the notorious 2013–2016 event known as "The Blob" in both size and surface temperatures.
The consequences of these marine heatwaves can be severe. NOAA Fisheries and its partners are closely monitoring the situation for potential impacts, which may include harmful algal blooms, threats to marine mammals, and the closure of shellfish fisheries. Past heatwaves have disrupted marine ecosystems, triggered die-offs, and caused shifts in species distributions throughout the Northeast Pacific Ocean. The combination of a persistent heatwave and an impending El Niño raises the stakes for coastal communities and industries that rely on healthy ocean conditions.
Looking ahead, the uncertainty surrounding the strength and duration of the coming El Niño looms large. While forecasts suggest a high probability of its arrival, the potential intensity remains difficult to pin down. NOAA’s estimate of a one in three chance for a strong event between October and December leaves ample room for surprises. The memory of past El Niño episodes—some bringing drought, others floods, and still others unexpected snow—serves as a reminder of the phenomenon’s capricious nature.
What is clear, however, is that El Niño acts as an amplifier of existing climate trends. Its ability to push global temperatures higher and tip the balance toward more frequent and severe weather extremes makes it a force to be reckoned with. As the world prepares for another round, scientists and policymakers alike are urging vigilance, adaptation, and continued research to better understand and respond to the challenges ahead.
As the Pacific stirs and the odds of El Niño’s return climb ever higher, communities from the Northwest to the equator—and far beyond—are bracing for a year that could test resilience, resourcefulness, and the limits of prediction in a warming world.