An amazing event for American television took place on February 14, 2005 on the CBS show Two and a Half Men. It rained twice. This is almost unknown in my surveying of place-related information on television, and it started in1973. The context of the events was very typical--the rain was needed by an event in the plot. In this one Charlie Sheen and his brother left the kid standing at school in the rain. They forgot about him. Since they forgot about him after school, it just had to rain to make it worse.
You also have the recent heavy rains and flooding in California making the rain events seem more realistic to viewers.