The El Niño forming across the Pacific has been turbocharged by a series of tropical cyclones that helped to shift the direction of trade winds, potentially adding to warming that’s evoking parallels with the record 1997-98 event.

Several cyclones, including a rare storm in the Southern Hemisphere this month, resulted in a strong reversal of trade winds near the equator, Australia’s Bureau of Meteorology said on its website on Tuesday. That’s set to increase temperatures below the surface, which then may raise sea surface temperatures further in the coming months, it said in a fortnightly update.

El Niños can affect weather worldwide by baking Asia, dumping rain across South America and bringing cooler summers to North America. This year’s pattern, the first since 2010, will probably bring warmer, drier weather to palm oil regions in Southeast Asia, Malayan Banking Banking Bhd. warned on Tuesday. Tropical commodities including palm oil are to be favored over other raw materials such as gold and copper this half as the El Niño raises risks, according to Oversea-Chinese Banking Corp.

The “El Niño will persist until at least the end of 2015,” the Australian bureau said. “Models also indicate that further warming is likely. Historically, El Niño reaches its peak strength during the late spring or early summer,” it said, referring to seasons in the southern hemisphere.

Three of five sea-surface temperature indexes are at their warmest sustained weekly value since the 1997-98 event, the bureau said. The so-called temperature anomaly in the central Pacific in June was the second warmest on record for the month, behind only 1997, it said. The El Niño of 1997-98 was the strongest on record, according to data collated by the National Oceanic and Atmospheric Administration.