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 (CFSv2) 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 from the ENSO‑CLIPER statistical model (Knaff and Landsea 1997, Wea. Forecasting, 12, 633‑652) are shown in Fig. F9.  Niño 3.4 predictions are summarized in Fig. F10, 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:

 

Though La Niña is favored to continue through the end of the year, the odds for La Niña decrease into the Northern Hemisphere late summer (52% chance in July-September 2022) before slightly increasing through the Northern Hemisphere fall and early winter 2022 (58-59% chance).

 

Discussion:

 

During May, below-average sea surface temperatures (SSTs) continued across most of the central and eastern equatorial Pacific Ocean (Fig. T18).  The monthly Niño index values ranged from -0.9C to -1.4C (Table T2).  Subsurface temperatures anomalies (averaged between 180-100W and 0-300m depth) also weakened with values returning to near zero.  Below-average subsurface temperatures persisted near the surface to at least ~75m depth from the central to the eastern equatorial Pacific Ocean, with above-average temperatures continuing at depth (~100 to 200m) in the western and central Pacific Ocean (Fig. T17).  Low-level easterly wind anomalies prevailed in the east-central equatorial Pacific, while upper-level westerly wind anomalies continued over most of the equatorial Pacific (Figs. T20 & T21).  Convection was suppressed over the western and central Pacific and was weakly enhanced over parts of Indonesia (Fig. T25).  Overall, the coupled ocean-atmosphere system continues to reflect La Niña.

The most recent IRI/CPC plume average for the Niño-3.4 SST index forecasts La Niña to persist into the Northern Hemisphere winter 2022-23 (Figs. F1-F12).  This is now in greater agreement with the forecast consensus this month, which also predicts La Niña to continue into the winter.  However, it is clear that recent observed oceanic and atmospheric anomalies have weakened and this is anticipated to continue through the summer.  Uncertainty remains over whether La Niña may transition to ENSO-neutral during the summer, with forecasters predicting a 52% chance of La Niña and a 46% chance of ENSO-neutral during July-September 2022.  After this season, the forecast is for renewed cooling, with La Niña favored during the fall and early winter.  In summary, though La Niña is favored to continue through the end of the year, the odds for La Niña decrease into the Northern Hemisphere late summer (52% chance in July-September 2022) before slightly increasing through the Northern Hemisphere fall and early winter 2022 (58-59% 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).