However, in an El Nino event, the opposite is true.
One of the first signs of an El Nino is the weakening of west-bound trade winds, or when the trade winds reverse direction and head toward the eastern coasts of the Pacific Ocean instead. Norwegian America meteorologist, Jacob Bjernes, suggested the weakening of the trade winds could be a result of an abnormal warm spot in the eastern pacific where it should be cool. As a result of such warming in the east, the temperature difference between eastern and western Pacific drops, and the strength of the west-bound trade winds reduces. The water that gets piled up in the western Pacific begins to move back to the east.