El Niño Expected to Impact California and Southeast with Severe Weather

California and the Southeast may face significant impacts from El Niño, which is predicted to be stronger this winter than it has been in decades. A meteorologist from NOAA’s Weather Prediction Center (WPC) indicated this on Monday. El Niño is intensifying across the Pacific Ocean and could bring severe weather to the United States through early 2027. Its effects might be felt nationwide, though specific states could experience particularly severe storms.

Notably strong El Niños can cause severe weather including flooding, damaging storms, droughts, and record-breaking heat in different global regions. The NOAA’s WPC predicts there is more than a 90 percent chance of a very strong event this year, impacting millions of Americans.

Understanding El Niño

El Niño is the warm phase of the El Niño–Southern Oscillation (ENSO), a climate pattern driven by interactions between the Pacific Ocean and the atmosphere. La Niña represents the cool phase of this cycle. This pattern features unusually warm sea-surface temperatures in the Pacific, which result in stormier weather in the Southern U.S. and drier conditions in some northern areas. It may also alter hurricane activities.

El Niño means the sea surface temperatures in the eastern Pacific, along the equator, off the coast of South America and Central America, are above normal, said Tony Fracasso, a meteorologist with the WPC. Fracasso noted that this is the current situation and is expected to continue into the winter season.

Some of the strongest El Niño episodes on record have coincided with major weather extremes. The 1997-98 Super El Niño contributed to severe flooding in California and Peru, while the 2015-16 event set global temperature records and caused widespread climate disruptions.

States Likely to Experience Greatest Impact

According to Fracasso, California and the Southeast are likely to see more intense storms due to El Niño. It can affect the storm track across the country, and the amount of warm air that it could bring in over the country and keep the colder air out of the lower 48, he explained.

California is expected to experience increased storm activity, with effects spreading across the country, leading to a warmer winter for most areas. Fracasso highlighted that every El Niño varies, and historical data shows more rain during El Niño years in California, though this is not always the case.

The southern U.S., particularly states near the Gulf and possibly the Carolinas, may also see wetter conditions this year. Although El Niño generally brings warmer temperatures, there remains potential for cold air and snow. Conversely, regions further north near the Great Lakes might experience drier conditions, according to Fracasso.

NOAA’s August 13 report predicted El Niño would continue strengthening through year-end, with a 69 percent chance of a historic event surpassing the strength of those since 1950. Expected snowfall increases are noted for areas in the West such as California, Nevada, Utah, Colorado, New Mexico, and Arizona.

Forecaster’s Predictions for ‘Unprecedented’ Events

Jeff Berardelli, a meteorologist with WFLA-TV in Tampa, anticipated a boost to El Niño within weeks, suggesting potential for unprecedented events. A strong push of west winds in the Tropical Pacific is likely to heighten warming, leading to peak strengths around 4.0° Celsius above average and breaking a 2015 record. For the southern U.S. and Florida, a strong subtropical jet stream may form by late fall, bringing frequent fronts, severe weather, and weekly rainfall — with more rain expected in California by winter.

The NOAA describes a subtropical jet stream as a fast-flowing band of westerly winds high in the atmosphere, typically located around 30 degrees latitude in both hemispheres.

The ‘Super El Niño’ Phenomenon

This year’s El Niño is informally dubbed a Super El Niño, a term for particularly strong events, last used in 2015 and 2016 when Pacific ocean temperatures surpassed average conditions. Fracasso acknowledged there are still a lot of unknowns about why this year’s El Niño is exceptionally strong.

We don’t know fully what the interaction is. It’s, it’s an oceanic deep in the currents, well below the sea level affecting the atmosphere above the ocean. And that interaction is hard to model. So, we don’t quite fully understand everything that’s going on, he said.

For more information, please contact Newsweek editors Anna Commander and Anthony Murray.