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, the odds for La Niña decrease into the late Northern Hemisphere summer (58% chance in August-October 2022) before slightly increasing through the Northern Hemisphere fall and early winter 2022 (61% chance).

 

Discussion:  

 

Below-average sea surface temperatures (SSTs) persisted during April across most of the central and eastern equatorial Pacific Ocean (Fig. T18).  Most Niño index values decreased, with the latest monthly values ranging from -0.7C to -1.4C (Table T2), which are quite negative for this time of year.  Subsurface temperatures anomalies (averaged between 180-100W and 0-300m depth) remained negative, reflecting an extensive area of below-average temperatures from the surface to ~100m depth across the central and eastern equatorial Pacific Ocean (Fig. T17).  For the monthly average, low-level easterly and upper-level westerly wind anomalies dominated the equatorial Pacific (Figs. T20 & T21).  Convection remained significantly suppressed around the Date Line and was enhanced over the Philippines (Fig. T25).  Overall, the coupled ocean-atmosphere system reflected the continuation of La Niña.

The most recent IRI/CPC plume average for the Niño-3.4 SST index forecasts borderline La Niña conditions during the Northern Hemisphere summer, with increasing odds for La Niña into the fall (Figs. F1-F12).  Similar to last month, the forecaster consensus predicts Niño-3.4 index values to weaken into the summer, but remaining below the threshold of La Niña (Niño-3.4 values equal to or less than -0.5C).  In the near-term, westerly wind anomalies are predicted for mid-late May which supports the weakening of below-average surface and subsurface oceanic temperatures in the coming months.  However, much of the model guidance is also hinting at a re-strengthening of La Niña conditions again in the fall and upcoming winter.  In summary, though La Niña is favored to continue, the odds for La Niña decrease into the late Northern Hemisphere summer (58% chance in August-October 2022) before slightly increasing through the Northern Hemisphere fall and early winter 2022 (61% 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).