Usually this has something to do with some weather phenomena that has come up, and is announced immediately when in effect by controllers, and updated in the next ATIS broadcast. IIRC, it goes something like:
"Hazardous weather for the Los Angeles International airport area available from HIWAS, FlightWatch, or Flight Service Station frequency."
Pretty much, you should get the same information from any of these sources, but as the FSS is next door (at HHR), you might get better details about what's going on there.
BL.