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
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
ENSO Alert System Status: La Niña Advisory
La Niña is expected to transition to ENSO-neutral
conditions by the end of April 2012.
La Niña weakened during
February 2012, as near- to- above average sea surface temperatures (SST)
emerged in the eastern equatorial Pacific Ocean (Fig. T18). However,
below-average SSTs persisted in the central Pacific, as indicated by the monthly
Niño-3.4 and Niño-4 indices which were near –0.8°C (Table T2). The
oceanic heat content (average temperature in the upper 300m of the ocean)
anomalies also weakened notably, as reflected by a shallow lens (0m to ~25m
depth) of positive temperature anomalies east of 125°W and by diminished
below-average temperatures east of the Date Line (Fig. T17). These
changes are partly associated with strong low-level westerly wind anomalies
across the eastern Pacific, which at times reflected the absence of equatorial
easterlies in that region (Figs. T20). Nonetheless, the larger scale atmospheric
circulation anomalies continued to reflect the ongoing La Niña. Enhanced low-level equatorial easterlies
persisted over the central and west-central Pacific, while convection remained
suppressed in the western and central Pacific, and enhanced over Malaysia and
the Philippines (Fig. T25). Collectively, these
oceanic and atmospheric patterns reflect a weakening La Niña.
A majority of models
predict ENSO-neutral conditions to return during March-May 2012 and to continue
through the Northern Hemisphere summer 2012 (Figs. F1-F13). The rapid weakening of the negative surface
and subsurface temperature anomalies during February 2012, combined with the
historical tendency for La Niña to dissipate during the Northern Hemisphere
spring, lends support to the return of ENSO-neutral conditions in the coming
months. Therefore, La Niña is expected
to transition to ENSO-neutral conditions by the end of April 2012.
updates of oceanic and atmospheric conditions are available on the Climate
Prediction Center homepage (El
Niño/La Niña Current Conditions and Expert Discussions).