El Niño’s Impact on U.S. Weather This Winter

El Niño: A Climate Pattern

El Niño is the warm phase of the El Niño-Southern Oscillation (ENSO), a climate pattern in the Pacific Ocean. It influences global weather systems. The cooler phase of this cycle is known as La Niña.

Changes include stormier weather in the Southern U.S. and drier conditions in northern areas. Hurricane activity may also be influenced.

Strengthening of El Niño

Federal forecasters predict El Niño will gain strength through the end of 2026. It has a 90 percent chance of becoming a very strong event during the fall and winter seasons.

The National Oceanic and Atmospheric Administration’s Climate Prediction Center updated its forecast. It expects a 75 percent chance of reaching historic strength between October and December. This is an increase from the previous forecast of 69 percent.

While strong El Niño events typically bring certain weather patterns, these effects are not guaranteed.

Potential Winter Impacts

AccuWeather expert Paul Pastelok shared possible weather changes for December. Expect heavy rainfall in central and Northern California and snow in the Sierras. The Northeast may also experience increased rain.

Another storm track could develop from the Gulf Coast to the Mid-Atlantic. This could lead to heavier rain in the Southeast and Tennessee Valley with severe thunderstorms. Mild conditions are anticipated in the Great Lakes, Midwest, and Northeast.

January and February might follow similar patterns. A strong storm track is likely into California, Nevada, and the Four Corners region. Less snow is expected in the Northwest and northern U.S. states, along with fewer cold air masses.

The Gulf Coast, Mid-Atlantic, and Southeast could be wet and stormy. Other factors may still influence these projections.

Climate Prediction Center Winter Outlooks

Maps from the Climate Prediction Center show forecasts for December 2026 to February 2027. The temperature outlook indicates above-normal conditions from the Pacific Northwest through the Plains, Midwest, and Northeast.

Most of the Southern U.S. is forecasted to experience warmer temperatures, though predictions are less certain for parts of California and the Southwest.

The precipitation outlook predicts wetter-than-normal conditions across Southern California, the Southwest, southern Plains, Gulf Coast, Florida, and parts of the East Coast.

Contact Newsweek editors: Ben Kelly and Sam Wilson.