NOAA says the current super El Niño is likely to become the strongest on record in over 75 years, sharpening the US cold weather forecast in winter as the Pacific warming pattern builds. The agency expects it to keep strengthening through fall and winter, when its weather effects are most likely to reach the U.S. and other regions.
El Niño is a periodic warming of water in the central and eastern Pacific Ocean near the equator, and it typically happens every three to four years. James Belanger of The Weather Company said NOAA uses longer-term data to filter out short-term changes in the weather and ocean from the El Niño signal, which is why the broader trend matters more than day-to-day shifts.
NOAA and James Belanger
Belanger’s explanation points to the way forecasters separate a lasting ocean pattern from short-lived weather noise. NOAA’s update is not about a single warm day or week in the Pacific Ocean; it is about whether the warming remains strong enough to affect weather for months.
That is the operational question for people in the U.S. this winter. A stronger El Niño tends to bring a wet southern U.S. in winter, while Australia and Indonesia typically face drought.
Erica Grow Cei on sea temperatures
Erica Grow Cei, a NOAA public affairs meteorologist, said, "Daily and weekly changes in sea-surface temperature are not tied to El Niño impacts over the United States," in an email to weather.com. Her point draws a hard line between short-range temperature swings and the larger pattern forecasters are tracking.
For readers, that means the day-to-day ocean readings matter less than whether the El Niño signal stays strong into winter. NOAA’s forecast says it will, and that is the period when the pattern can influence rainfall, temperatures and hurricane seasons.
Atlantic and Pacific Oceans
NOAA also said a stronger El Niño tends to have a significant impact on hurricane seasons in both the Atlantic and Pacific Oceans. The Atlantic has seen nine named storms this season, but only one has become a hurricane, and Isaias did not reach hurricane strength until late on Oct. 7.
Oct. 7 was the latest first hurricane in the satellite era from 1966 to the present. In past super El Niño seasons, only one hurricane across four seasons combined formed after Oct. 7, and this year could end with just one hurricane, which would be a modern-era record low.
For people in the U.S., Australia and Indonesia, the practical read is simple: the El Niño signal is still strengthening, and the next months are the ones most likely to bring its weather effects into focus.
