Climate troublemaker El Niño has an 80 percent chance of developing this winter, federal scientists announced Thursday.

“The official forecast favors the formation of a weak El Niño,” NOAA’s Climate Prediction Center said in its monthly forecast. The center gives it an 80 percent chance of continuing through the winter.

The chances have increased since early October, when climate scientists gave it a 70 to 75 percent chance of forming.

El Niño is a natural climate pattern that’s defined as unusually warm seawater in the central Pacific Ocean. It affects weather patterns in the USA and around the world.

Although forecast to be on the weak side, El Niño “may still influence the winter season by bringing wetter conditions across the southern United States and warmer, drier conditions to parts of the North,” Mike Halpert, deputy director of the prediction center, said in a statement last month.

This episode also has a 55 to 60 percent chance of lasting into the spring, the CPC said. 

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 strong episode, which led to weather-related crop damage, fires and flash floods, Reuters 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,”

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