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: Not Active

 

Outlook:

 

ENSO-neutral is favored during the Northern Hemisphere winter 2019-20 (70% chance), continuing through spring 2020 (~65% chance).

 

Discussion:  

 

Above-average sea surface temperatures (SSTs) were observed in the central tropical Pacific Ocean during November, with regions of above and below average SSTs observed farther east (Fig. T18). Monthly SST indices were above average in the Niño-3 and Niño-3.4 regions (+0.5C to +0.6C, respectively) and in the westernmost Niño-4 region (+0.9C), while remaining below average in Niño-1+2 (-0.4C; Table T2).  The equatorial subsurface temperature anomalies (averaged across 180°-100°W) returned to near zero during the month, reflecting the progression of Kelvin waves to the east (Fig. T17). The low-level winds were near average during November (Fig. T20), while easterly upper-level wind anomalies were observed over the western Pacific (Fig. T21).  Finally, tropical convection was suppressed near and east of the Date Line and also over Indonesia, and somewhat enhanced over the western Pacific northeast of Papua New Guinea (Fig. T25).  The overall oceanic and atmospheric system was consistent with ENSO-neutral. 

The majority of models in the IRI/CPC plume (Figs. F1-F12) continue to favor ENSO-neutral (Niño-3.4 index between -0.5C and +0.5C) through the Northern Hemisphere summer.  Many dynamical model forecasts suggest Niño-3.4 SST index values may remain near +0.5C into December before decreasing toward zero.  Forecasters agree with this consensus and believe the chances for El Niño to be 25-30% during the winter and spring.  In summary, ENSO-neutral is favored during the Northern Hemisphere winter 2019-20 (70% chance), continuing through spring 2020 (~65% 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).