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

A globe-style map of temperature anomalies in the Pacific Ocean, centered on the ENSO-monitoring region at the equator

ENSO: Not Active

Surface temperatures in the east-central tropical Pacific were near to above average in October 2019, but the atmosphere did not react to the warmth. Sub-surface heat that spread across the basin in mid-September was dispersing. Thus, of the three possible outcomes—return of El Niño, La Niña, or neutral—forecasters give neutral the highest odds (70% chance) of continuing through winter. 

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 October 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

A graph of sub-surface heat anomalies at the equator in the Pacific from December 2018 through October 2019

November 2019 ENSO update: the people in your neighborhood

November 14, 2019

While ENSO-neutral conditions are expected to continue through the winter,  some other climate patterns are out and about in the tropical neighborhood.

Read more

A build-up of sub-surface heat in mid-September 2019 began dissipating in October. Forecasters think it was simply natural variability, not a sign of El Niño returning.