When seasonal to interannual climate fluctuations associated with El Niño occur in the Pacific (at right), a ridge of high pressure (shown as small arrows representing jetstream winds) develops over the west coast of North America, causing higher than normal temperatures in that region (shown in orange). Storms, that under normal conditions (shown above) would pass through Washington and Oregon, are often steered northward toward Alaska (heavy arrow). These conditions also are favorable for the development of storms in the Gulf of Mexico that can bring heavy rains to the southern U.S. Floods, droughts, and heat waves associated with El Niño conditions can affect the productivity of agriculture and fisheries and cause heat related health problems. Research on the processes that link the tropical Pacific Ocean to the global atmosphere has enabled scientists to predict the onset of individual El Niño events and their effects on weather patterns worldwide