A strengthening super El Niño is expected to become the dominant driver of U.S. weather during the coming months, with forecasters warning that one of the strongest events in decades could begin reshaping rainfall, storm tracks and snowfall patterns as fall progresses into winter.
El Niño occurs when ocean waters across the equatorial Pacific become warmer than average, altering atmospheric circulation and influencing weather around the globe. Confidence that the climate pattern will meet the threshold for a super El Niño is near 100 percent, AccuWeather said on Thursday.
While some early signals may emerge by October, meteorologists say the phenomenon’s most noticeable impacts are likely to intensify from late fall into winter, bringing wetter conditions to parts of the South and California while leaving other regions warmer or drier than average.
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What Is a Super El Niño, and What Does It Mean for Fall and Winter?
A super El Niño develops when warming in the tropical Pacific reaches unusually high levels, strengthening the atmospheric ripple effects that influence weather worldwide.
While the National Oceanic and Atmospheric Administration (NOAA) does not officially use the term “super El Niño,” instead classifying events by strength categories such as “strong” and “very strong,” the phrase is widely used by other forecasting agencies, meteorologists and researchers to describe exceptionally intense El Niño episodes. NOAA has said the developing event is already showing signs that it could reach the agency’s “very strong” category by winter.
For the U.S., the classic super El Niño pattern often brings additional storms to California and the southern tier of states. The northern United States frequently experiences milder conditions, while parts of the Pacific Northwest may trend drier than average.
However, meteorologists caution that El Niño is only one factor influencing winter weather, and individual storms can still produce outcomes that differ from the seasonal pattern. AccuWeather long-range forecaster Paul Pastelok told Newsweek that a detailed forecast for the developing El Niño has not yet been finalized, and its eventual impacts could still differ from current expectations.
When Will the 2026 Super El Niño Begin to Hit U.S. States?
Some weather-related impacts, which Pastelok called “previews” of the El Niño impacts to come, have already been felt in the U.S., such as the drought and fires across the Pacific Northwest and the Rocky Mountains, which could be influenced by warming water temperatures in the Pacific Ocean associated with the strengthening El Niño.
The dry spells felt across the center of the U.S. in July, such as in Iowa and Nebraska, also could have been influenced by El Niño, although Pastelok said he doesn’t think these are “direct effects,” as those that are more likely in the cooler season.
The strongest El Niño impacts are felt in North America in the cooler seasons because that is when the northern and southern jet streams interact with each other, Pastelok said.
The U.S. Southwest and the region from Texas to the Tennessee Valley could begin to see changes in weather in late October to November, Pastelok said. The number of “upper lows,” or areas of low pressure in the middle or upper atmosphere, coming into the area will increase the chances of rain and flooding.
“That’s the first sign of El Niño picking up,” Pastelok said.
In response to the change, drier conditions will be felt across the Great Lakes and Upper Midwest by mid-fall or later in the fall.
Severe weather will start in Florida and southern Georgia in November, with Jacksonville, Tampa and Orlando at risk of tornadoes beginning in November, Pastelok said. Impacts across Southern California, particularly heavy rain at lower elevations, will pick up as early as November but likely become more prolific in December.
How Will the Super El Niño Impact the U.S. Ski Season?
The outlook is mixed depending on location. Many of the nation’s premier ski areas in Utah, Colorado and California could benefit from a stronger storm track and increased precipitation, potentially boosting snowfall totals and improving snowpack conditions during the winter months. Meteorologists say the central Sierra Nevadas in California has historically benefited from strong El Niño events, while Utah’s Wasatch Range is often well positioned to receive frequent snowstorms.
Conditions may be less favorable farther north. Oregon and parts of the Pacific Northwest can experience below-average snowfall during strong El Niño winters, while some northern Rocky Mountain resorts face a less certain outlook.
Forecasters also note that rising temperatures linked to climate change could cause a greater share of winter precipitation to fall as rain rather than snow at lower elevations, even during a wet El Niño season.
Super El Niño Snowfall Predictions
New winter outlook maps released by weather forecasters at OpenSnow suggest the strongest snowfall opportunities may shift toward parts of the U.S. Southwest and southern Rockies, while some northern-tier states could see below-average snowfall.
Among states expected to benefit the most are California and Utah, where forecasters see favorable conditions for above-average snowfall in many mountain locations. Heavy Pacific storm systems could repeatedly target the Sierra Nevadas while delivering healthy snow totals to parts of the central and southern Rockies.
Elsewhere, the outlook becomes more variable. Colorado resorts may fall near the dividing line between wetter and drier storm tracks, making snowfall forecasts less certain. Oregon, Montana and portions of the northern Rockies could see reduced snowfall relative to the average in a classic strong El Niño pattern.
Much of the Midwest, northern U.S., Great Lakes and Northeast are expected to receive below-average snowfall totals.
What Happens Next
While some effects associated with El Niño may already be emerging in parts of the Pacific, forecasters say the phenomenon’s influence on U.S. weather typically becomes more pronounced during the fall and winter months. As ocean temperatures continue to warm and the atmosphere responds, El Niño can begin to reshape storm tracks, alter rainfall patterns and influence temperatures across large portions of the country. The strongest and most widespread impacts often occur between late fall and early spring, when the climate pattern reaches its peak strength.
Contact Newsweek editors on this story: Jenna deJong and Dave Siminoff.