Moderate size earthquakes in Southern California in July 1986 and October 1987 were associated with similar antecedent monthly mean anomaly patterns of sea level pressure over the far western contiguous United States and eastern North Pacific. This apparent relationship and a long time series of such patterns in past Julys and Octobers suggest that further research of this nature might be of value in earthquake prediction. ¿ American Geophysical Union 1988