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

 

Outlook:

 

There is a greater than 90% chance that El Niño will continue through Northern Hemisphere winter 2015-16, and around an 80% chance it will last into early spring 2016.

 

Discussion:  

 

            During June, sea surface temperature (SST) anomalies exceeded +1.0°C across the central and eastern equatorial Pacific Ocean (Fig. T18).  Compared to last month, the largest SST anomaly increases occurred in the Niño-3 and Niño-3.4 regions, while the Niño-4 and Niño-1+2 indices were approximately the same (Table T2).   Positive subsurface temperature anomalies weakened due to the eastward shift of an upwelling oceanic Kelvin wave, which reduced above-average temperatures at depth in the central and east-central equatorial Pacific (Fig. T17).  In many respects, the atmospheric anomalies remained firmly coupled to the oceanic warming.  Significant westerly winds were apparent in the western equatorial Pacific and anomalous upper-level easterly winds continued (Figs. T20, T21). The traditional and equatorial Southern Oscillation Index (SOI) were both negative (Table T1 & Fig. T2), which are consistent with enhanced convection over the central and eastern equatorial Pacific and suppressed convection over Indonesia (Fig. T25).  Collectively, these atmospheric and oceanic features reflect an ongoing and strengthening El Niño.

Nearly all models predict El Niño to continue into the Northern Hemisphere winter 2015-16, with many multi-model averages predicting a strong event at its peak strength (3-month values of the Niño-3.4 index of +1.5°C or greater;  Figs. F1-F13).  At this time, the forecaster consensus is in favor of a significant El Niño in excess of +1.5°C in the Niño-3.4 region.  Overall, there is a greater than 90% chance that El Niño will continue through Northern Hemisphere winter 2015-16, and around an 80% chance it will last into early spring 2016.

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