indices indicated a further weakening of La Niņa during April 2008 (Table
SST anomalies weakened in the central and east-central equatorial
, while positive SST anomalies were
confined to parts of the eastern equatorial Pacific (Fig.
T18). The latest weekly Niņo-3.4 index was -0.9°C, and the Niņo-4 index was -1.0°C.
these surface conditions, the oceanic thermocline was near normal across the
equatorial Pacific east of 150°W during April, and continued to deepen west of
the Date Line (Fig. T16).
Consistent with this structure, sub-surface temperatures at thermocline depth
became above average (+1°C to +3°C) across the eastern equatorial Pacific and
in the area west of 170°W (Fig. T17).
low-level easterly anomalies persisted across the western and central equatorial
Pacific during April (Fig. T20,
in association with the ongoing pattern of enhanced convection across the far
western tropical Pacific and suppressed convection over the central equatorial
Pacific (Figs. T25,
E3). These atmospheric anomalies
continue to strongly reflect La Niņa.
the latest status of the ENSO cycle see the ENSO Diagnostic Discussion at: