There was a time, before population growth, irrigation evaporation and smog, that you could see Catalina Island quite frequently from coastal North San Diego County. Now it is the exception, often after a rain, that you can see the Catalina Island, and San Clemente Island as well.
Here are pictures of Catalina Island from Beacons Beach.
And, the same day – 12-30-2012 – Catalina is shrouded by rain and an approaching sunset.
Here is a picture of San Clemente Island