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 ENSO‑CLIPER statistical model (Knaff and Landsea 1997, Wea. Forecasting, 12, 633‑652) are shown in Fig. F11.  Niño 3.4 predictions are summarized in Fig. F12, 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:

 

A weak El Niño is likely to continue through the Northern Hemisphere summer 2019 (65% chance) and possibly fall (50-55% chance).

 

Discussion:  

 

El Niño continued during March 2019, as above-average sea surface temperatures (SSTs) persisted across the equatorial Pacific Ocean (Fig. T18). The monthly values of the Niño3.4 and Niño4 indices were near +1.0°C, while the Niño3 value was +0.7°C (Table T2). The anomalous upper-ocean heat content (averaged across 180°-100°W) decreased during March but remained well above average, as the above-average temperatures at depth peaked in early March in association with a downwelling equatorial oceanic Kelvin wave (Fig. T17). Enhanced equatorial convection was observed near the Date Line and in the western Pacific, while suppressed convection prevailed over western Indonesia (Fig. T25).  Low-level wind anomalies were westerly in the western Pacific Ocean during March. Meanwhile, upper-level winds were mostly near average (Figs. T20, T21). The equatorial and traditional Southern Oscillation Index values were negative (Fig. T2 and Table T1). Overall, these features are consistent with a weak El Niño. 

The majority of models in the IRI/CPC plume predict a Niño 3.4 index of +0.5°C or greater through the remainder of 2019 (Figs. F1-F12).  Most forecasters expect SST anomalies in the Niño 3.4 region to remain between +0.5°C and +1.0°C for at least the next several seasons, indicating a weak El Niño. However, because forecasts made during spring tend to be less accurate, the predicted chance that El Niño will persist through fall is currently 50-55%.  In summary, a weak El Niño is likely to continue through the Northern Hemisphere summer 2019 (65% chance) and possibly fall (50-55% chance).

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