From December 1992 to February 1993, 18 meridional sections of temperature, salinity, and current were collected along 156¿E, from 5¿S to 5¿N, during the Intensive Observation Period of the Coupled Ocean-Atmosphere Response Experiment. The average conditions were characteristic of the ongoing El Ni¿o event, with a relatively shallow thermocline and fresh surface waters. Alternating westerly and easterly wind forcing was observed, and the warm surface layer (the ''Warm Pool'') responded in a time scale of a few days by corresponding alternating flows; the equatorial current system was less affected at depth. The upper-layer oceanic temperature variability involved several mechanisms, including surface cooling by evaporation during westerly winds and entrainment from the thermocline. ¿ American Geophysical Union 1994