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

Globe-style map of the tropical Pacific Ocean showing difference from average temperature in November 2019

ENSO: Not Active

Temperatures across the tropical Pacific were above average in November, but sub-surface heat content was near normal as were surface winds. Of the three possible outcomes—return of El Niño, La Niña, or neutral—forecasters continue to 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 November 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

ENSO, El Nino, La Nino, temperature anomaly

December 2019 ENSO update: neutral, rinse, repeat

December 12, 2019

Our blogger reports that there is little to report...and shares some ENSO trivia. Read more

Beneath the ocean surface, a warmer-than-average pool of water occupies the eastern tropical Pacific (red colors), but an opposing wave of cooler-than-average water is coming up behind it (blue). NOAA Climate.gov image based on CPC data.