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:  El Niño Advisory/ La Niña Watch

 

Outlook:

 

A transition to ENSO-neutral is likely during late Northern Hemisphere spring or early summer 2016, with an increasing chance of La Niña during the second half of the year. 

 

Discussion:  

 

            Sea surface temperature (SST) anomalies were between 1.0° and 1.5°C across most of the central and eastern equatorial Pacific Ocean during early April (Fig. T18),  having weakened appreciably over the last month. Except for Niño-1+2, all monthly Niño indices decreased from the month prior (Table T2). The subsurface temperature anomaly in the central and eastern Pacific decreased to negative values in association with a significant expansion of below-average temperatures at depth (Fig. T17). Low-level westerly wind anomalies and upper-level easterly wind anomalies weakened compared to February (Figs.T20, T21). The equatorial Southern Oscillation Index (SOI) remained negative but weakened, while the traditional SOI was near zero (Table T1 & Fig. T2). Enhanced convection continued over the central tropical Pacific but weakened east of the Date Line, and was suppressed over northern Indonesia and the Philippines (Fig. T25). Collectively, these anomalies reflect a weakening El Niño.

Nearly all models predict further weakening of El Niño, with a transition to ENSO-neutral likely during late spring or early summer 2016 (Figs. F1-F13). Then, the chance of La Niña increases during the late summer or early fall.  The official forecast is consistent with the model forecasts, also supported by a historical tendency for La Niña to follow strong El Niño events.  A transition to ENSO-neutral is likely during late Northern Hemisphere spring or early summer 2016, with an increasing chance of La Niña during the second half of the year.

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