Forecast Forum

The canonical correlation analysis (CCA) forecast of SST in the central Pacific (Barnett et al. 1988, Science, 241, 192‑196; Barnston and Ropelewski 1992, J. Climate, 5, 1316‑1345), is shown in Figs. F1 and F2. This forecast is produced routinely by the Prediction Branch of the Climate Prediction Center. The predictions from the National Centers for Environmental Prediction (NCEP) Coupled Forecast System Model (CFSv2) are presented in Figs. F3 and F4a, F4b.  Predictions from the Markov model (Xue, et al. 2000: J. Climate, 13, 849‑871) are shown in Figs. F5 and F6.   Predictions from the latest version of the LDEO model (Chen et al. 2000: Geophys. Res. Let., 27, 2585‑2587) are shown in Figs. F7 and F8. Predictions from the ENSO‑CLIPER statistical model (Knaff and Landsea 1997, Wea. Forecasting, 12, 633‑652) are shown in Fig. F9. Nino 3.4 predictions are summarized in Fig. F10, provided by the Forecasting and Prediction Research Group of the IRI.

The CPC and the contributors to the Forecast Forum caution potential users of this predictive information that they can expect only modest skill.

 

ENSO Alert System Status: Not Active

 

Outlook: ENSO-Neutral is likely in the Northern Hemisphere summer 2025 (82% chance in June-August) and may continue into winter 2025-26, though confidence is lower (48% chance of Neutral and 41% chance of La Nina in November-January).

 

Discussion:

 

In the past month, ENSO-neutral conditions persisted, with sea surface temperatures (SSTs) near average over most of the equatorial Pacific Ocean (Fig. T18). The monthly Nino index values ranged from -0.2C to +0.2C (Table T2). Subsurface ocean temperatures were near-to-above average (averaged across 180-100W), with above-average subsurface ocean temperatures at depth in the central and western Pacific (Fig. T17). For the month, low-level wind anomalies were easterly over the east-central Pacific, while upper-level winds were mostly near average across the equatorial Pacific Ocean (Figs. T20 & T21). Convection was enhanced over Indonesia (Fig. T25). Collectively, the coupled ocean-atmosphere system in the tropical Pacific reflected ENSO-neutral.

The IRI and North American Multi-Model Ensemble predictions indicate ENSO-neutral is most likely through the Northern Hemisphere winter 2025-26 (Figs. F1-F12). The forecast team also continuously favors ENSO-neutral through early 2026, with smaller chances that La Nina could form during winter 2025-26.  In summary, ENSO-Neutral is likely in the Northern Hemisphere summer 2025 (82% chance in June-August) and may continue into winter 2025-26, though confidence is lower (48% chance of Neutral and 41% chance of La Nina in November-January).

Weekly updates of oceanic and atmospheric conditions are available on the Climate Prediction Center homepage (El Nino/La Nina Current Conditions and Expert Discussions).