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

ENSO: Not Active

The El Niño of 2019 is over, and neutral conditions have returned to the tropical Pacific. Trade winds did relax in mid-September, allowing a deep wave of warm water to spread eastward beneath the surface. Still, of the three possible outcomes—El Niño, La Niña, or neutral—forecasters give neutral the highest odds (85% chance) of lasting through fall. 

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

(image at left) Difference from average sea surface temperatures at the equator in the tropical Pacific in August 2019. 

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

Globes showing typical climate impacts over the U.S. during El Niño and La Niñaca

El Niño is anchored in the tropical Pacific, but it affects seasonal climate "downstream" in the United States. In the summer, El Niño's primary influence on U.S. climate is on the hurricane season in both the eastern Pacific and the Atlantic. 

Typical ENSO impacts
Winter temperature and precipitation
Hurricane season impacts
Current outlooks
6-10 day outlook
8-14 day outlook
1-month outlook
3-month outlook

Animated gif of global maps of winter and summer impacts of El Niño

El Niño has its strongest influence on global climate during the Northern Hemisphere winter, but summer impacts do occur, especially in the tropics. 

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

Cross-section of the upper 700 meters of the tropical Pacific Ocean showing sub-surface temperatures in September 2019 compared to the 1981-2010 average

October 2019 ENSO update: fright night

October 10, 2019

There's no El Niño at present, but "no news" in the tropical Pacific has implications for the Atlantic hurricane season. 

Read more

A wave of warm water spread across the tropical Pacific in early October 2019, but odds for an ENSO-neutral fall remain high.