El Niño is still warming up in the bullpen.
The infamous climate troublemaker, long promised to develop this winter, still hasn't officially arrived, federal scientists announced Thursday.
The odds remain high, however: "There is a 90 percent chance of El Niño forming this season, meaning there is a 10 percent chance it will not form," said Mike Halpert, deputy director of NOAA's Climate Prediction Center. The center is the federal organization responsible for the official El Niño declaration.
El Niño is a natural climate pattern that's defined as unusually warm seawater in the central or eastern Pacific Ocean. It affects weather patterns in the USA and around the world. Typical U.S. impacts include stormy weather in the western and southern United States, and drier, warmer conditions in parts of the north.
Although the ocean water is warm enough for an El Niño designation, Halpert said, the atmosphere above the ocean has yet to respond to this warmth. Both are needed to declare an El Nino has formed.
The World Meteorological Organization, a United Nations agency, said late last month that "sea-surface temperatures are already at weak El Niño levels in part of the tropical Pacific, although the corresponding atmospheric patterns have not yet materialized."
Halpert said that "if an El Niño develops it is expected to be weak. Still, it may influence the winter season by bringing wetter and stormier conditions across the southern United States and drier conditions in parts of the north."
Looking later into 2019, the center gives a 60 percent chance that the El Niño will continue into the spring.
The entire natural climate cycle is officially known as El Niño – Southern Oscillation (ENSO), which swings between warmer and cooler seawater in the tropical Pacific. The cycle is the primary factor government scientists consider when announcing their winter weather forecast.
The cooler pattern, known as La Niña, was dominant the past two winters. The most recent El Niño occurred during the winter of 2015-16. That was a particularly powerful episode, which led to droughts, flooding and coral bleaching in different parts of the world, the World Meteorological Organization said.
The forecast released Thursday said the government's ENSO alert system remains as an "El Niño Watch." Once El Niño develops, the alert level will rise to "El Niño Advisory."