The Eastern Pacific is cooler than usual, and unusually cool water extends farther westward than is usual (see the blue color extending further off-shore from South America along the equator).
Strong La Niña conditions during December 1998 are shown in the top panel. The Eastern Pacific is cooler than usual, and unusually cool water extends farther westward than is usual (see the blue color extending further off-shore from South America along the equator).