Large disked shape object with lots of lights hovering above a drive-in movie theater in Auburn/Federal Way around 1977.

I can’t remember the exact date, but it was between 1977 and 1978, as I was about 5 or 6.  My entire family was in our VW bug, watching a black and white movie (i.e. nothing a young kid wanted to watch, as I remember).  During the movie, the screen went all fuzzy and everyone was honking, then just along the trees above the theater a large object was hovering above us.  
As a child, it looked enormous and had lots of lights circling around it and there was no sound of engines or anything.  It was right above us, so there was no mistaking the massive object (i.e. not some small object far in the distance)!  
It hovered for about 30 seconds, or so, and then it shot off instantaneously and was gone behind the row of trees.  After it left, the movie came back on clear and was no longer fuzzy.
It was sorta like a scene out of the twilight zone, with the effect on the movie screen and all. My mom, dad and older brother all saw the same thing, so I know it wasn’t a kid’s imagination.  Even to this day, and despite being a young kid, the memory is ingrained in my mind.
Witness indicates that the date of the sighting is approximate.  PD