There are many cruises from San Diego. This is the complete schedule of cruises in 2017 and 2018.
Spring cruises out of San Diego go to Hawaii, the Mexican Riviera, South America, through the Panama Canal, and up the Pacific Coast. Unfortunately, there are no summer cruises from this port. In the fall, cruises go to Australia as well as Mexico, South America, Hawaii, and nowhere. Winter cruises leaving from San Diego go to the Mexican Riviera and through the Panama Canal.
For more departures from Southern California, check the cruises out of Los Angeles. That port isn't far from San Diego.