La Niña conditions continued this past month, as indicated by the below-average sea surface temperatures (SSTs) across the central and east-central equatorial Pacific Ocean [Fig. 1]. The latest weekly indices were -0.6°C in Niño-3.4 and -0.9°C in Niño-4, with values close to zero in Niño-1+2 and Niño-3 [Fig. 2]. Below-average subsurface temperatures persisted [Fig. 3], with below-average temperatures dominating the central and eastern equatorial Pacific Ocean [Fig. 4]. Low-level wind anomalies remained easterly over the western and central Pacific, while upper-level wind anomalies were westerly over the central Pacific. Convection was suppressed over the Date Line and western Pacific and was enhanced over Indonesia [Fig. 5]. The traditional and equatorial Southern Oscillation indices were positive. Collectively, the coupled ocean-atmosphere system indicated La Niña conditions.

The IRI multi-model average predicts weak La Niña conditions to continue through February-April 2025 and then transition to ENSO-neutral [Fig. 6]. The IRI dynamical model average and several of the models from the North American Multi-Model Ensemble (NMME) predict an earlier transition to ENSO-neutral in January-March 2025. The forecast team favors a weak La Niña through February-April, but there is also a 41% chance of ENSO-neutral emerging in this season. A weak La Niña is less likely to result in conventional winter/spring impacts, though predictable signals can still influence the forecast guidance (e.g., CPC's seasonal outlooks). In summary, La Niña conditions are expected to persist in the near-term, with a transition to ENSO-neutral likely during March-May 2025 (66% chance; [Fig. 7]).