El Niño typically has its strongest influence on the US in the fall and winter, forecasters say.
One important effect: El Niño tends to drive the average west-to-east storm track farther south than usual. This brings the Pacific's winter storms to California more often, rather than to the Pacific Northwest. Depending on how intense this El Niño is, this could be good news for drought-stricken California. The Northwest, along with western Canada and southern Alaska, tends to dry out during an El Niño and post warmer-than-normal temperatures.
As winter storms continue to move east, they bring cooler and wetter-than-normal conditions to the states along the southern tier. The Northeast also tends to be warmer than normal. During the summer, conditions tend to return to normal across North America, except for a wetter-than-normal patch in the northern Great Basin and Columbia Plateau.