The large-scale thermal structure of the California Current during 1982-83 shows several anomalous conditions: warm sea surface temperature anomalies (~1.-2 ¿C), depression of the thermocline by 50 m or more, and pronounced subsurface warming (~3-4 ¿C) relative to the 30-year mean. The subsurface anomaly is much greater than the surface anomaly. These persistent (>6 months) structures, coupled with unusually high sea levels along the North American coast, show that a major Californian ''El Ni¿o'' occurred during 1982-83. The data support the conclusion that the expansion and intensification of the Aleutian low and the decrease in strength of the Pacific high produced an anomalous basin-wide atmospheric circulation which coupled directly to the large-scale oceanic wind-driven circulation to produce the Californian ''El Ni¿o.'' The enhanced transport from the west (offshore California) and south (Baja California), which such a circulation would produce, is consistent with the observed water properties. The equatorial 1982-83 El Ni¿o is probably related to the Californian ''El Nin¿'' through an atmospheric teleconnection between equatorial sea surface temperature and the atmospheric Hadley circulations.