La Niña Weakens Mid-Winter, ENSO-Neutral Expected Through Spring With Possible El Niño Later
What the latest ENSO outlook is saying
After a few months of La Niña conditions, NOAA’s Climate Prediction Center expects those conditions to weaken and “fizzle out” around mid-winter, with a transition to ENSO-neutral. In practical terms, that means the ocean-atmosphere pattern known as ENSO (El Niño–Southern Oscillation) is anticipated to move away from a La Niña phase and settle into a neutral phase for a time.
The same outlook also notes that a transition to El Niño could happen later, potentially as the year moves into summer or fall. While that possibility is on the table, the timing and strength of any shift to El Niño are not yet certain.
Understanding La Niña, El Niño, and ENSO-neutral
La Niña and El Niño are defined by changes in ocean surface temperatures in a key region of the Pacific Ocean: the central and east-central equatorial Pacific. These changes are important because they can influence weather patterns far beyond the tropics.
La Niña occurs when ocean surface temperatures in the central and east-central equatorial Pacific reach a specific cooler-than-average threshold.
El Niño is the warming of that same region of the Pacific Ocean and is associated with a different set of weather effects around the planet.
ENSO-neutral refers to periods when conditions are neither in a La Niña nor an El Niño phase, meaning ocean temperatures and related atmospheric patterns are closer to average for that region.
According to the outlook, as La Niña weakens and the system transitions to ENSO-neutral, ocean temperatures will warm in the east-central equatorial Pacific. That warming is a key piece of the expected shift away from La Niña.
How long neutral conditions may last
NOAA’s update favors ENSO-neutral conditions persisting at least through late spring. In other words, even as La Niña fades, the most likely near-term scenario is not an immediate jump to El Niño, but rather a period when ENSO’s signature is weaker.
After late spring, there is a chance El Niño conditions could develop as the calendar progresses into summer or fall. However, the forecast emphasizes uncertainty: it is still too early to determine exactly if and when a shift to El Niño will occur, and how strong it might become if it does develop.
What this could mean for hurricane season
For those looking ahead to Atlantic hurricane season, the possibility of El Niño later in the year is described as potentially good news. In general, El Niño typically means fewer Atlantic hurricanes because stronger wind shear is present, making it more difficult for storms to develop.
At the same time, the outlook cautions against overconfidence in any single scenario. Because it is too early to know whether El Niño will form, when it might form, or how strong it could be, hurricane expectations should be framed as conditional rather than definitive.
Why ENSO matters beyond the tropics
Although La Niña and El Niño are rooted in the equatorial Pacific, their effects can extend far beyond that region. Changes in the equatorial Pacific can affect weather patterns thousands of miles away, including near the United States, as well as globally.
It is also important to keep perspective: ENSO is not the only driver of weather patterns. Even so, it is a major factor that can tilt the odds toward certain seasonal outcomes, especially when the signal is strong.
Typical U.S. winter tendencies during La Niña
While ENSO is not the sole influence on weather, La Niña is commonly associated with a recognizable set of winter tendencies in the United States. These are not guarantees for every location or every year, but they describe the typical direction La Niña can push seasonal conditions.
Temperature patterns: La Niña usually means a warmer winter in the South and a colder winter in the Northern Plains.
Precipitation patterns: It also typically brings a wetter-than-normal winter in the Pacific Northwest and the Ohio Valley, and a drier winter for the South.
These tendencies help explain why the expected weakening of La Niña matters: if the La Niña signal fades, the “tilt” it provides to winter patterns can become less pronounced.
What changes when ENSO turns neutral
With a transition to ENSO-neutral, ENSO is not expected to play as strong a role in shaping weather. That does not mean weather becomes predictable or uniform; rather, it means the specific push provided by La Niña or El Niño is reduced.
However, the outlook also notes that La Niña may continue to have a lingering influence through early spring. This is a reminder that climate patterns do not always flip like a switch. Even after conditions are categorized as neutral, the atmosphere and ocean can retain some momentum from the previous phase.
Watching for the next shift
The outlook’s key storyline is a progression: La Niña weakening by mid-winter, a likely period of ENSO-neutral conditions through at least late spring, and then a chance of El Niño development in summer or fall. The expected warming in the east-central equatorial Pacific is consistent with that direction of travel.
Still, the forecast underscores uncertainty about the details of any potential El Niño. Questions such as “Will it form?” “When will it form?” and “How strong will it be?” remain open at this stage. That uncertainty is especially relevant for people trying to connect ENSO to downstream impacts, such as hurricane activity or seasonal temperature and precipitation patterns.
Key points to remember
NOAA’s Climate Prediction Center expects La Niña to weaken and transition to ENSO-neutral around mid-winter.
ENSO-neutral conditions are favored to persist at least through late spring.
Ocean temperatures are expected to warm in the east-central equatorial Pacific as the transition occurs.
There is a chance El Niño conditions could develop in summer or fall, but it is too early to determine timing or strength.
El Niño typically means fewer Atlantic hurricanes due to stronger wind shear, though the outlook remains uncertain.
La Niña and El Niño can affect weather patterns thousands of miles away, including near the U.S., but ENSO is not the only driver of weather.
Even with a shift to neutral, La Niña may have lingering influence through early spring.
Conclusion
The current outlook points toward an easing of La Niña’s influence as mid-winter approaches, followed by a stretch of ENSO-neutral conditions that could last into late spring. During this neutral period, ENSO is expected to play a less dominant role in shaping weather patterns, even if some residual La Niña influence persists into early spring. Looking further ahead, the potential emergence of El Niño in summer or fall is a possibility rather than a certainty, and both the timing and intensity remain unclear. For seasonal planning—whether focused on general weather expectations or the broader context of hurricane season—the most responsible takeaway is to track updates over time as the Pacific continues to evolve.