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 (CFS03) 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 using linear inverse modeling (Penland and Magorian 1993: J. Climate, 6, 1067‑1076) are shown in Figs. F9 and F10. Predictions from the Scripps / Max Planck Institute (MPI) hybrid coupled model (Barnett et al. 1993: J. Climate, 6, 1545‑1566) are shown in Fig. F11.  Predictions from the ENSO‑CLIPER statistical model (Knaff and Landsea 1997, Wea. Forecasting, 12, 633‑652) are shown in Fig. F12.  Niño 3.4 predictions are summarized in Fig. F13, 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: La Niña Advisory

 

Outlook:

 

A transition to ENSO-neutral is expected to occur by February 2017, with ENSO-neutral then continuing through the first half of 2017.

 

Discussion:  

 

La Niña continued during December, with negative sea surface temperature (SST) anomalies continuing across the central and eastern equatorial Pacific (Fig. T18). The weekly Niño index values fluctuated during the last month, with the monthly averaged Niño-3 and Niño-3.4 values at -0.4°C (Table T2). The upper-ocean heat content anomaly was near zero when averaged across the eastern Pacific, though near-to-below average subsurface temperatures were evident closer to the surface (Fig. T17). Atmospheric convection remained suppressed over the central tropical Pacific and enhanced over Indonesia (Fig. T25). The low-level easterly winds were slightly enhanced over the western Pacific, and upper-level westerly anomalies were observed across the eastern Pacific (Fig. T20 & Fig. T21). Overall, the ocean and atmosphere system remained consistent with a weak La Niña.

The multi-model averages favor an imminent transition to ENSO-neutral (3-month average Niño-3.4 index between -0.5°C and 0.5°C), with ENSO-neutral lasting through August-October (ASO) 2017 (Figs. F1-F13).   Along with the model forecasts, the decay of the subsurface temperature anomalies and marginally cool conditions at and near the ocean surface portends the return of ENSO-neutral over the next month. In summary, a transition to ENSO-neutral is expected to occur by February 2017, with ENSO-neutral then continuing through the first half of 2017 (click CPC/IRI consensus forecast for the chance of each outcome for each 3-month period).

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