El Niño & La Niña (El Niño-Southern Oscillation)

El Niño Watch

The odds of El Niño emerging in the tropical Pacific by fall have dropped slightly to 60% (from 65%), but remain at 70% by winter. Click through the tabs above to understand what that could mean for U.S. and global climate.

More ENSO status information
Latest official ENSO update
Latest ENSO blog update

(image at left) Sea surface temperatures at the equator were warmer than average (orange, red) in the eastern Pacific in July 2018. A long-lasting warm spell in the central-eastern tropical Pacific is one of the criteria for El Niño.

El Niño and La Niña are the warm and cool phases of a recurring climate pattern across the tropical Pacific—the El Niño-Southern Oscillation, or “ENSO” for short.

The pattern can shift back and forth irregularly every two to seven years, and each phase triggers predictable disruptions of temperature, precipitation, and winds.

These changes disrupt the large-scale air movements in the tropics, triggering a cascade of global side effects.

More about El Niño
What is El Niño in a nutshell?
Understanding El Niño (video)
ENSO alert system criteria
ENSO essentials
Educational Resources on ENSO

El Niño is anchored in the tropical Pacific, but it affects seasonal climate "downstream" in the United States. This map shows some of the precipitation and temperature impacts we may experience if El Niño develops this winter as predicted, but not all impacts occur during every event, and their strength and exact location can vary. 

Typical U.S La Niña impacts
Winter temperature and precipitation
Hurricane season impacts
Current outlooks
6-10 day outlook
8-14 day outlook
1-month outlook
3-month outlook

El Niño and La Niña have their strongest impact on global climate during the Northern Hemisphere winter.  The map at left shows some of the precipitation and temperature patterns that might occur this coming winter if El Niño develops as predicted. However, not all impacts appear during every El Niño event.  

More information
ENSO's cascade of global impacts
The Walker Circulation
More maps of global impacts of La Niña and El Niño

August 2018 ENSO Update: Game show edition

July 12, 2018

Odds for El Niño remain at around 70% for winter 2018-2019. The Climate Prediction Center's Emily Becker lets you in on all of the details of what's going on, so you better "come on down" and take a look.

Read more


Warmer-than-average water remains underneath the surface of the tropical Pacific Ocean through July 2018. Figure by NOAA Climate.gov, based on data from the Climate Prediction Center.