El Niño: Quick Facts

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Last updated

Nov. 2, 2026

News •

Is El Niño making storms and flash floods in the Southwest worse? • Nov. 2, 2026, 6:58 PM ET (AP)

US winter is likely to be wetter and warmer, forecasters say. If you want more snow, look south • Oct. 15, 2026, 5:55 PM ET (AP)

Facts

Also Known As	ENSO

Photos

How strong El Niño conditions develop

Map of the tropical Pacific Ocean highlighting the four ENSO (El Niño-Southern Oscillation) regions: Niño 4, Niño 3.4, Niño 3, and Niño 1+2. The regions are marked as colored rectangles along the equator from near Australia to the coast of South America, illustrating key zones used to monitor El Niño and La Niña climate events.

Two diagrams compare coastal upwelling during normal conditions and an El Nino event. The top shows strong upwelling with nutrient-rich water and high plankton near the coast, while the bottom shows weak upwelling, a thicker nutrient-poor surface layer, and reduced plankton during El Nino.

World map illustrating the generalized weather effects of El Nino from December through February. Regions are labeled and shaded to show conditions such as warm in parts of North America, Asia, and South America; wet in the southern United States and eastern South America; dry and warm in southern Africa and Southeast Asia; wet and cool in the northern United States; and wet and warm across central and eastern equatorial Pacific.

Images of sea-surface height taken during the El Nino episodes of 1997 and 2015.

Graph depicting the influence of El Niño/Southern Oscillation (ENSO) on rainfall produced by the Indian summer monsoon. During years when ENSO is active, monsoon-driven precipitation over India often declines.

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Topics

What Is the Difference Between El Niño and La Niña?Climate change Monsoon ocean current El Niño/Southern Oscillation Southern Oscillation La Niña Ekman spiral Ekman layer West Greenland Current Equatorial current thermohaline circulation How Do Ocean Currents Affect the Biosphere?whirlpool gyre

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