The El Nino that’s upending weather across South America and Asia has intensified to the strongest on record, according to Japan’s national forecaster, threatening widespread economic disruptions that could linger long after the climate pattern dissipates.

Sea surface temperatures in a patch of the tropical Pacific Ocean monitored by the Japan Meteorological Agency were 4 C above normal as of September, the highest in records going back to 1949, the forecaster said in a bulletin published Friday. The previous record was set in December 1997, when temperatures were 3.7 C above normal, the bureau said.

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El Nino has already disrupted weather patterns worldwide. The climate event has led to the weakest Indian monsoon in more than a decade, exacerbated wildfires in Indonesia that have spewed toxic smoke over neighboring Singapore and Malaysia, and threatened sugar and coffee output in Brazil.

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The JMA’s outlook comes a day after the World Meteorological Organization said in its latest seasonal forecast that El Niño is set to be the most intense ever. The WMO’s projection is based on the Niño 3.4 region, which overlaps with but lies west of the Nino 3 region tracked by Japan.

The Japanese bureau predicts a 100 percent chance that El Nino will persist through the Northern Hemisphere winter, in line with the US Climate Prediction Center’s outlook that the weather-roiling phenomenon is certain to last through the January-March period.