At the Airport, where Gidget's dad runs into an old friend, the man sitting behind them, who looks at them strangely and then leaves in a hurry, is Victor Jory!! Uncredited, but it is Victor Jory!.
It is very rare to have thunderstorms in Southern California and this is the second major storm this season!
Houses in Southern California don't have basements or cellars! The vast majority of houses in Southern California during this time period (50s and 60s) did have the electrical panel on the back porch.
The title of this episode is a play on the title of The Beatles's classic song, which is also the title to their first movie: A Hard Day's Night (1964).