Satellite measurements of sea surface temperature (SST) in the eastern equatorial Pacific have been made since 1982 using the multichannel advanced very high resolution radiometers on NOAA polar orbiting satellites. A 4-year data set has been accumulated at weekly intervals and a spatial resolution of about 50 km on an interactive computer system. The time lapse evaluation of the data reveals annual and interannual variations of the SST which are related to the 1982--1983 El Ni¿o and Southern Oscillation as well as to coastal and equatorial upwelling events. The El Ni¿o was preceded by a weak equatorial cooling pattern from May to August 1982. The subsequent equatorial warming persisted until June 1983. From mid-1983 to early 1984, the equatorial SST pattern was dominated by pronounced upwelling and westward advection of cold water by the South Equatorial Current. North of the equator the zonal equatorial SST front was distorted by a succession of westward moving equatorial long waves which extended nearly to the date line. During both 1984 and 1985 the equatorial upwelling began to intensify during May and lasted until the following February. The transition to seasonal equatorial warming occurred from February to March and was marked by abrupt increases of SST on time scales of less than 1 week. The zonal equatorial SST fronts disappeared at this time, but the upwelling off the coast of South America persisted. From December to April of each year, short-term upwelling events appeared intermittently along the western coast of Central America south of the Gulf of Tehuantepec and southwest of Lake Nicaragua and the Gulf of Panama. These upwelling events were weak from 1982 to 1984 and were more intense during 1985 and 1986. During February and March of 1985, an extreme case of upwelling was observed south of the Gulf of Panama. The SST was depressed by at least 9¿ C, and cooler water appeared to be advected southwestward to the equator and the Galapagos Islands. Time series of the sea surface temperatures at fixed locations and color images of the SST distribution are used to illustrate these events.