A striking North American snowfall map is circulating as El Niño strengthens, and the timing makes it easy to read the colors as a forecast for the coming winter. That is not what the map shows.
NOAA’s Climate Prediction Center said in its August 13 update that there is a greater than 90% chance of a very strong El Niño during the Northern Hemisphere fall and winter of 2026–27. The agency also placed the probability of an exceptionally strong October–December event — one with a three-month Relative Oceanic Niño Index of at least +2.5°C — at 69%. Those figures make this a season worth watching closely.
The snowfall map, however, is based on historical composites. NOAA examined moderate-to-strong El Niño winters and compared January-to-March snowfall with the 1991–2020 average. The result shows where snow has tended to be above or below average when the tropical Pacific has been in a similar phase.
The broad pattern favors more snowfall across parts of the southern half of the United States, especially at colder, higher elevations in the West. Lower snowfall has been more common around the Great Lakes, interior New England, the northern Rockies and Pacific Northwest, western Canada and much of Alaska. These tendencies are consistent with shifts in the Pacific jet stream and storm tracks during El Niño.
But snowfall is more complicated than precipitation alone. A wetter winter does not automatically mean a snowier winter if temperatures are too warm. Elevation matters, local storm tracks matter, and short-lived cold-air outbreaks can determine whether precipitation falls as rain or snow.
NOAA explicitly warns against treating the composite as destiny. Even very strong El Niño events do not produce the textbook pattern everywhere, and individual winters show substantial variation. The current event may increase the odds of some familiar outcomes, but it cannot tell a resident of Denver, Dallas, Boston or Seattle how many inches will fall in a particular storm months in advance.
The scientific value of the map is probabilistic. It provides a baseline for how the atmosphere has behaved in past El Niño winters and helps forecasters understand which seasonal tendencies deserve more weight. As autumn progresses, those historical signals will be combined with current ocean temperatures, atmospheric circulation, model guidance and shorter-range forecasts.
For the 2026–27 winter, the headline is not that a single snowfall map has predicted where the snow will be. It is that the Pacific is developing an unusually strong climate signal, one that can meaningfully tilt the odds while still leaving plenty of room for the atmosphere to surprise us.