A "super" El Niño, characterised by sea surface temperatures climbing by at least 2C, is forecast to bring a wet winter to portions of the western and south-eastern US, according to climate models. Experts warn that coastal areas in these regions may be at an elevated risk of flooding.
Climate scientists predict this year's El Niño will be the strongest of the century. The US National Oceanic and Atmospheric Administration (Noaa) states the weather system is expected to intensify during the fall and winter, continuing until early spring 2027.
California has a 70%-100% chance of experiencing above-average rainfall along its coast, based on a model from the European center for medium-range forecasts. Daniel Swain, a UCLA climate scientist, noted that while El Niño does not guarantee a specific outcome, a strong event like the one predicted increases the likelihood of a wet winter and coastal flooding, particularly during strong storms or king tide events.
Historically, past El Niños have caused significant damage in California, including the destruction of homes in 1982-83 and massive flooding and storm-related deaths in 1997-98. During the 2015-16 El Niño winter, California beaches experienced record coastal erosion.
Similar high odds of increased precipitation are facing swathes of the US Gulf coast and east coast, from Florida up to the mid-Atlantic region. Noaa reports that central and south Florida have historically seen more severe weather, including tornadoes and flood events, during El Niño years.