A rapidly strengthening "super" El Niño is likely to influence snowfall patterns across the United States this winter, potentially boosting mountain snow in parts of the West while suppressing it across portions of the northern U.S. The developing event, or "super" El Niño as it is frequently dubbed, is indeed unusually powerful. The World Meteorological Organization (WMO) said on September 3 that the El Niño is now “firmly established” and is expected to intensify into a very strong event before peaking toward the end of 2026.
Its forecast puts the likelihood that El Niño will persist through February 2027 at nearly 100 percent. That comes as the National Oceanic and Atmospheric Administration's (NOAA) Climate Prediction Center says there is a greater than 90 percent chance of a very strong El Niño this fall and winter. The NOAA has even calculated a 69 percent chance that the October to December period will reach a level exceeding previous El Niño events in records dating all the way back to 1950, based on its Relative Oceanic Niño Index.
Crystal Egger, meteorologist and president of Monarch Weather Consulting, told Newsweek that the strength of the event could substantially tilt the odds toward characteristic El Niño weather, but cautioned against it being a guarantee. "A strong El Niño can tilt the odds toward certain temperature and precipitation patterns across different parts of the U.S., but it doesn’t determine exactly how every storm, or even the entire winter, will play out," she said. An El Niño pushes the Pacific jet stream farther south, bringing a more active storm track and additional moisture across the southern United States.
NOAA analyses show that moderate-to-strong El Niño winters have, generally, produced increased snowfall across parts of the southern half of the country. This is most common at higher elevations in the West. Egger said California, Nevada, Utah, Colorado, New Mexico and Arizona are among the states that could see more snow in the months to come.
"Historically, strong El Niño winters tend to favor a wetter storm track across the southern tier of the U.S.," she said. "That can translate to above-average snowfall across parts of the southern and central Rockies and the higher elevations of the Southwest." Any increase in snowfall would be particularly important in the mountains, where winter snowpack acts as a natural reservoir, storing water that is gradually released as it melts during the spring and summer. "And this year, the need for mountain snow is particularly important," Egger said.
"Much of the West is coming off a very dry start to the water year, so building that snowpack will be critical for water supplies and overall drought conditions heading into 2027." NOAA's latest seasonal outlook shows that heavier precipitation in these areas is expected. The agency expects the influence of the El Niño to become increasingly pronounced as winter progresses, with above-normal precipitation favored across much of California, the Southwest and southern tier. NOAA currently gives much of coastal California and neighboring southern Arizona greater than a 50 percent chance of above-normal precipitation during parts of the winter.
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