EL NIÑO/SOUTHERN OSCILLATION (ENSO) DIAGNOSTIC DISCUSSION
CLIMATE PREDICTION CENTER/NCEP/NWS and the International
Research Institute for Climate and Society 5 April 2012 ENSO
Alert System Status: La Niña Advisory Synopsis: La Niña is
expected to transition to ENSO-neutral conditions during April
2012. La Niña continued to weaken during March 2012, as below-
average SSTs persisted primarily in the central Pacific (Fig.
1). All of the Niño indices have warmed considerably during the
last two months, and the Niño 4 and Niño 3.4 indices averaged
only near -0.5 in March (Fig.2). The oceanic heat content
(average temperature in the upper 300m of ocean) anomalies also
continued to warm (Fig. 3), with alternating pockets of negative
and positive temperature anomalies observed within the upper 100
m in the central and eastern Pacific (Fig. 4). Significant
anomalous low-level westerly winds developed in the western
tropical Pacific in late March, associated with the MJO (Fig.
5). This wind event could further warm the