AUSTIN (KXAN) — The Climate Prediction Center updated its outlook for ENSO (El Niño-Southern Oscillation) and La Niña is expected to begin by this November.
La Niña is the cold phase of ENSO, where the waters in the eastern equatorial Pacific cool at least 0.5° below average.
The odds of La Niña continuing through meteorological winter (December-February) are at 77%, but La Niña is not expected to last long into 2025.
The Climate Prediction Center described the outlook for this upcoming La Niña as “weak and short,” which would have implications for the upcoming winter forecast.
What a weak La Niña means for winter
La Niña usually provides a relatively predictable pattern for winters in North America, but the strength of La Niña impacts that predictability.
Remember, a typical La Niña means drier and warmer for most of the southern states, while being wetter and colder for many of the northern tier states as the Pacific Jet Stream is usually farther north (see image).
But, according to the CPC updated outlook, a weaker La Niña is “less likely to result in conventional winter impacts, though predictable signals could still influence the forecast guidance.”
That would mean a winter outlook that only loosely resembles the map above.
Impacts on Central Texas
If a weaker La Niña is less likely to bring its usual warm and dry pattern to Central Texas this winter, that only increases our chances for more rain than a typical La Niña winter would. It also means that the accuracy of a winter outlook may be harder to nail down without the usual influences of El Niño or La Niña at play.
Still, it’s not like La Niña won’t exist at all, but just in a weaker fashion. We’ll still probably have warmer and drier periods than a typical winter, but potentially not to the extent where significant drought settles back in.
When will La Niña end?
This “short duration” La Niña is expected to begin during the 3-month period September-November with the odds favoring a return to ENSO Neutral during the February-April period in early 2025.
Beyond that, it’s too early to say, but odds for El Niño appear to creep up as we head through late spring 2025, even while odds for ENSO Neutral and La Niña are still higher.