The European Centre for Medium-Range Weather Forecasts says El Niño is rapidly locking into place, with sea surface temperatures in the Pacific Ocean projected to peak 3 to 4 degrees Celsius above average this fall. That is well above the 2 degrees Celsius level many meteorologists use to identify a super El Niño, and it points to a stronger winter signal for the U.S.
The latest ECMWF seasonal forecast raises the odds of above-average precipitation for the East Coast and the West Coast, including California, during the months when El Niño usually exerts its strongest influence. The event is expected to reach peak strength from November through January.
ECMWF forecast and 2 degrees Celsius
July ECMWF model runs had already pointed to an increased signal of above-average precipitation for the East Coast, and the latest update pushes the ocean warmth deeper into what many meteorologists describe as super El Niño territory. The benchmark matters because the forecasted anomaly is not just meeting that threshold; it is aimed at topping it by a wide margin.
El Niño is one phase of ENSO, the El Niño-Southern Oscillation. During El Niño, warmer than average water across the central and eastern Pacific helps shift the atmosphere in ways that favor stronger winds, which suppress tropical development in the Atlantic and enhance it in the Eastern Pacific.
East Coast and West Coast of the U.S.
For the East Coast, the ECMWF model points to a greater likelihood of above-average precipitation stretching from New England through Florida, with coastal areas singled out for the clearest signal. For the West Coast, the forecast also leans wetter, and much of the West Coast, including all of California, faces increased chances of above-average rain.
A wider and wavier Pacific jet stream is helping steer more storms into the West Coast region. For California, that setup raises the risk of atmospheric rivers, which could bring heavy rain to the lowlands and a high threat of flooding.
November through January
The timing matters because this particular El Niño is expected to peak from November through January, when winter weather patterns usually have the strongest grip on the U.S. coasts. Residents from New England to Florida and across California are now looking at a forecast that is leaning wetter, while the same ocean pattern also points to quieter Atlantic tropical activity.
Will the forecasted 3 to 4 degrees Celsius anomaly actually materialize by peak season? The next useful marker is the winter stretch itself, when the U.S. will see whether the stronger Pacific signal translates into the wetter coast-to-coast pattern now sitting in the ECMWF forecast.
