In this study we use the National Centers for Environmental Prediction (NCEP) monthly sea surface temperature (SST) fields (1982--1994) to investigate the temporal and spatial variabilities of the South China Sea (SCS) warm/cool anomalies. Three steps of analysis were performed on the data set: ensemble mean (T&blmac;), composite analysis to obtain the monthly mean anomaly relative to the ensemble mean (T˜), and empirical orthogonal function (EOF) analysis on the residue data relative to(T&blmac;)+(T˜). The ensemble mean SST field (T&blmac;) has a rather weak horizontal gradient: 29 ¿C near the Borneo coast to 25¿--26 ¿C near the southeast China coast. Two areas of evident SST anomalies were found in the monthly T˜ variation: west of Borneo-Palawan Islands (WBP) and southeast of the southern Vietnam coast (SVC). Four patterns, monsoon and transition each with two out-of-phase structures, were found. During the spring-to-summer transition (March to May) the warm anomaly is formed in the northern SCS with T˜>1.8 ¿C located at 112¿--119¿30'E, 15¿--19¿30'N. During the fall-to-winter transition (October to November) the northern SCS (north of 12 ¿N) cool anomaly is formed in November with T˜<-0.6 ¿C located at 108¿--115 ¿E, 13¿--20 ¿N. We performed an EOF analysis on the residue data relative to T&blmac;+T˜ in order to obtain transient and interannual variations of the SST fields. EOF1 accounts for 47% of the variance and represents the northern SCS warm/cool anomaly pattern. EOF2 accounts for 14% of the variance and represents the southern SCS dipole pattern. Strong northern SCS warm anomaly (1 ¿C warmer) appears during October--November 1987 and January--February 1988, and strong northern SCS cool anomaly (1 ¿C cooler) occurs during March 1986 and November 1992. Furthermore, a strong cross correlation between wind stress curl and SST anomalies, computed from the European Centre for Medium-Range Weather Forecast analyzed wind stress data and the NCEP SST data for different lags, shows the existence of an air-sea feedback mechanism in the SCS deep basin.